Association Between Soil Lead and Blood Lead - Evidence

Mark A. S. Laidlaw

Sometime in the near future it probably will be shown that the older urban areas of the United States have been rendered more or less uninhabitable by the millions of tons of poisonous industrial lead residues that have accumulated in cities during the past century. Clair C. Patterson, National Academy of Sciences (1980)

Source - Laidlaw and Filippelli (2008)

Historical Emissions of Lead from Leaded Gasoline - Top 90 U.S. Cities

Source - Mielke, Laidlaw and Gonzales (2010)

An example of the lead poisoning epidemic - Detroit, Michigan

View Lead Poisoning Percentages in Each Detroit School

Plot of Soil Lead Versus Children's Blood Lead in Detroit - Bickell 2010

Source - Bickell (2010)

Eclampsia is a life-threatening complication of pregnancy, is a condition that causes a pregnant woman, usually previously diagnosed with preeclampsia (high blood pressure and protein in the urine), to develop seizures or coma.

Childhood lead poisoning (Zahran et al., 2013a), (Zahran et al., 2013b) and preeclampsia/eclampsia (Zahran et al., 2014) have been shown to be associated with lead in soil and dust.

1) Childhood lead poisoning is one of the most common pediatric health problems in the United States today (CDC, 2014); Source
2) “Preeclampsia ... is the leading cause of maternal death worldwide and a major cause of preterm delivery”.... "Predicting preeclampsia is a major step towards saving the lives of many women”.Source

Link to several studies suggesting a link between lead and eclampsia

Funding should be therefore be directed towards understanding and preventing children’s and child bearing women’s exposure to lead in soil and dust.
Plot of Temporal Variation in Atmospheric Soil and Lead in Detroit - 2001-2009

Scatterplot with median splines of weather adjusted air lead and air soil in time (daily). Weather-adjusted air Pb and soil estimates (µg/m3) are graphed on the daily time-step, fitting distributions of air Pb and soil values with median splines.

Source - Zahran S., Laidlaw M.A.S., McElmurry S.P., Filippelli G.M. Taylor M. (2013)

Supplemental Material

Plot of Temporal Variation in Atmospheric Lead and Children's Blood Lead in Detroit - 2001-2009

Weather-adjusted air Pb (µg/m3) and blood Pb (µg/dL) by age group. Average monthly child blood Pb levels adjusted by local weather conditions, child gender, method of blood draw, and census tract fixed effects

Source - Zahran S., Laidlaw M.A.S., McElmurry S.P., Filippelli G.M. Taylor M. (2013)

Supplemental Material

Early Childhood Lead Exposure and Academic Achievement:Evidence From Detroit Public Schools, 2008–2010 (Zhang et al, 2013)

New Orleans, Louisiana (USA)


Source - Howard Mielke - Xavier (New Orleans)


New Orleans Soil Pb Blood Pb Dose Response - Most Recent

Link to Source

Syracuse, New York


Link to Source

Link to Source

Indianapolis, Indiana (USA)

Points represent blood lead poisoning cases (>10 ug/dl) between 1992 and 1994

Based upon a sample of only 8% of children

Link to Source

Chicago, Illinois


Link to Source (dead link) Penn State Graduate Student Study

Link to separate United States Geological Survey (USGS)Soil Lead Study of Chicago


Distribution of soil lead in 87 Chicago Gardens - Finster et al. (2003)

Pilot Study of the Relationship of Regional Road Traffic to Surface-Soil Lead Levels in Illinois (Argonne National Laboratory, 1987)

Gasoline Pb in soil of Chicago Play Areas (Argonne National Laboratory, 1986)


Chicago Blood Lead Seasonality - 1967 and 1968.


Link to Philadelphia, Pennslyvania - Soil Lead Map

Philadelphia, Pennslyvania : Lead Poisoning Risk Analysis

Link to Source

Oakland, California


Los Angeles, California


Link to paper

Link to California Soil Lead Studies

Sacramento, California


Link to Solt Thesis

Link to California Soil Lead Studies

California Automotive Pb Emissions: 1950 to 1982

Link to Source

Link to California Soil Lead Studies

Minneapolis and St. Paul Minnesota(USA)


El Paso, Texas

Link to Source

Source - SCERP Monograph Series no. 12, The U.S-Mexican Border Environment: Integrated Approach to Defining Particulate Matter Issues in the Paso del Norte Region.

Link to CDC El Paso Discussion of Study

Paris, France

Link to Source

Great Britain

The British Geological survey systematically sampled Pb in the soils of 22 cities in Great Britain - Link.

Moscow, Russia

Link to Source

Prague, Czech Republic

Link to Source


Link to Source

London, England

Link to Source

Glasgow, Scotland

Link to Source

Sydney, Australia

Link to Source

Link to Source

Link to Source

Omaha, Nebraska

Link to Source

Berlin, Germany - Soil Lead Map

Karlsruhe, Germany - Soil Lead Map

Peer Reviewed Evidence That Exterior Soil Is The Primary Source of Interior Lead Loading and Lead Concentration in House Dust

2014 French Study

2014 Sydney Australia Study

Typical Pattern of Roadside Lead in Soil Found In Urban Cities


Robin Raftis of IUPUI actually completed the work for this transect.
Source(Filippelli et al., 2005)- 3.5mb

Urban Soil Lead Comes from Two Main Sources

1. Emissions from Past Use of Lead in Gasoline
2. Exterior Lead Paint

(note - lead smelters can be main sources when present as well)


Schematic of Typical Pattern of Urban Soil Lead Concentration

Link to Source

Discussion of Association between Soil Lead and Blood Lead

The Emerging Paradigm About The Cause of Urban Lead Poisoning

The emerging lead poisoning paradigm is that chronic urban lead poisoning is caused by exposure to lead contaminated soil (contaminated from past leaded gasoline emissions and exterior lead paint) that is tracked into the interior of homes by shoes(Hunt et al., 2006)and the feet and fur of family pets and exterior urban soil that is re-suspended into the atmosphere where it penetrates interiors of homes and settles on interior contact surfaces(Layton and Beame, 2009)(Laidlaw and Filippelli, 2008). Children are also exposed to lead via direct ingestion of soil outdoors. Chronic urban lead poisoning can also be caused by exposure to lead paint particles. Sometimes, children are exposed to lead originating from BOTH lead paint particles AND from exterior lead contaminated soil dust. Children are primarily exposed via hand to mouth activity (thumb sucking). Acute lead poisoning is probably caused by ingestion of interior and exterior lead paint that has chipped or via ingestion of a large dose of soil with high lead concentrations.

See also, Filippelli and Laidlaw, 2010

Pathways of Pb Exposure - USEPA, November, 2008

Source - USEPA Staff, 2008

Boston - Bivariate correlations among environmental measures and childs blood lead

Source - Rabinowitz et al

Migration Pathways of Contaminated Soil and Airborne Particulates to Indoor Dust

Source - Layton and Beamer

A Large Portion of House Dust Is Composed of Soil

Investigator % House Dust From Soil
Hawley (1985)
Thornton et al. (1985)
Camann and Harding (1989)
Fergusson and Kim (1991)
Calabrese and Stanek (1992)

Source - Estimates of the relative contribution of exterior soil to house dust (Paustenbach et al, 1997).

Based upon the table above, it should be easily understood that if the exterior soils are contaminated with Pb, the interior house dust will be contaminated with Pb as well.

Synchrotron Analysis Studies Supports Hypothesis That Pb in Outdoor Soil Is Significant Contributor to INDOOR dust Pb

Laidlaw et al. Sydney House and Soil XAS Study

Pingitore et al. 2011 - Contributions of Paint and Soil to Pb in Household Dust Wipes: An XAS Study

Maclean et al. 2011 - Application of Synchrotron X-ray Techniques for the Determination of Metal Speciation in (House) Dust Particles

Blood Lead Incidence Maps

The blood lead incidence rates in most large urban areas of the United States are probably similar to those shown on the blood lead incidence maps of Detroit, Milwaukee, and Cleveland (below).

Milwaukee, Wisconsin

Milwaukee Soil Lead Study


2009 Milwaukee Blood Lead Seasonality Study

Older Milwaukee Blood Lead Seasonality Study

Milwaukee Soil Lead Study


Cleveland, Ohio- Soil Lead

Detroit, Michigan

Note the soil lead background concentrations in Detroit's northern suburbs.

Link to Source of Figures 4 and 5

Plot of Soil Lead Versus Children's Blood Lead in Detroit - Bickell 2010

View Lead Poisoning Percentages in Each Detroit School

Source - Detroit Free Press

Providence, Rhode Island

Link to Source

Grand Rapids, Michigan


Louisville, Kentucky


The National Health and Nutrition Examination Survey (NHANES) III 1999-2002 database indicates that approximately 2.4 million children have blood Pb levels between 5 and 9.9 microgram/deciliter (Iqbal et al., 2008) and that within that population of 1-'5-year olds with blood Pb levels of 5 microgram/deciliter or higher, the prevalence was 47% for non-Hispanic Black children, 28% for Mexican American children, and 19% for non-Hispanic White children (Bernard, 2003). The fact that children of color are nearly 4 times more likely than white children to have blood Pb levels between 5 and 10 microgram/deciliter (and 13 times more likely to have blood Pb levels above 20 microgram/deciliter; Bernard and McGeehin, 2003) raises concerns about social justice and the long-term health of these children.

New Orleans Soil Pb Blood Pb Dose Response - Most Recent

Link to Source

Dose-Response- Syracuse, New York (USA)

Dose-Response- New Orleans, Louisiana (USA)


Link to Source

Link to Source


Dose-Response- New Orleans, Louisiana (USA)

Zahran S, et al. Children's blood lead and standardized test performance response as indicators of neurotoxicity in metropolitan New Orleans elementary schools, Neurotoxicology (2009), doi:10.1016/j.neuro.2009.07.017

Dose-Response- Tijuana (Mexico)


Dose-Response - Detroit

Plot of Soil Lead Versus Children's Blood Lead in Detroit - Bickell 2010

Source - Bickell (2010)

Dose-Response- USEPA IEUBK Model

Other Dose Response Information

  • Lanphear et al. (1998): increasing soil lead concentration from background to 400 micrograms/g was estimated to produce an increase of 11.6% in the percentage of children estimated to have a blood lead level exceeding 10 micrograms/dL.

  • Malcoe et al. (2002): Logistic regression of yard soil lead >165.3 mg/kg (OR, 4.1; CI, 1.3-12.4) were independently associated with BPbs greater than or equal to 10 microg/dL.

  • Texas Dept. of Health (2004): Using large database from El Paso Area, study found an odds ratio 4.5 (1.4, 14.2)for the relationship between a 500 ppm increase in soil lead and blood lead level > 10 ug/dl.

  • Maisonette (1997): yard soil remediation showed the strongest association with changes in blood lead levels. This variable was found to be a protective factor for elevated blood lead levels in children (odds ratio, 0.28; confidence interval, 0.08-0.92).

2011 Lead Poisoning Health Effects Review Paper - Highly Recommended!

Lead in Soil Is Associated With Eclampsia (Zahran et al., 2014)

Eclampsia Definition: Eclampsia, a life-threatening complication of pregnancy, is a condition that causes a pregnant woman, usually previously diagnosed with preeclampsia (high blood pressure and protein in the urine), to develop seizures or coma.

Source - Sammy Zahran, Sheryl Magzamen, Ian M.Breunig, Howard W.Mielke (2014)

S2014 Study Showing Relationship Between Mothers Blood Lead Concentration and Eclampsia

"Preeclampsia ... is the leading cause of maternal death worldwide and a major cause of preterm delivery," Dr. Sibai said. "Predicting preeclampsia is a major step towards saving the lives of many women."


Link to several studies suggesting a link between lead and eclampsia

2012 Association Between Aggravated Assault and Air Pb - Six City Study - Highly Recommended!

Toxicity Below 10 ug/dl - Cognitive

Canfield, R.L., Henderson, C.R., Cory-Slechta, D.A., Cox, C., Jusko, T.A., & Lanphear, B.P. Intellectual impairment in children with blood lead concentrations below 10 g/dL: The Rochester cohort study. The New England Journal of Medicine 348(16):1517-1526.

Chiodo LM, Covington C, Sokol RJ, Hannigan JH, Jannise J, Ager J, Greenwald M, Delaney-Black V. 2007. Blood lead levels and specific attention effects in young children. Neurotoxicol Teratol.

Schnaas L, Rothenberg SJ, Flores MF, Martinez S, Hernandez C, Osorio E, Velasco SR, Perroni E. Reduced intellectual development in children with prenatal lead exposure. Environ Health Perspect. 2006 May;114(5):791-7.

Surkan PJ, Zhang A, Trachtenberg F, Daniel DB, McKinlay S, Bellinger DC. Neurotoxicology. Neuropsychological function in children with blood lead levels <10mug/dL. 2007 Jul 25.

Miranda ML, Kim D, Galeano MA, Paul CJ, Hull AP, Morgan SP. 2007. The relationship between early childhood blood lead levels and performance on end-of-grade tests. Environ Health Perspect. 2007 Aug;115(8):1242-7.

Zahran S, et al. Children's blood lead and standardized test performance response as indicators of neurotoxicity in metropolitan New Orleans elementary schools, Neurotoxicology (2009), doi:10.1016/j.neuro.2009.07.017

Chandramouli, L. et al. 2009. Effects of early childhood lead exposure on academic performance and behaviour of school age children. Archives of Disease in Childhood. Online First: 21 September 2009. doi:10.1136/adc.2008.149955


Accompanying powerpoint pdf

Nigg JT, Nikolas M, Mark Knottnerus G, Cavanagh K, Friderici K. 2010. Confirmation and extension of association of blood lead with attention-deficit/hyperactivity disorder (ADHD) and ADHD symptom domains at population-typical exposure levels. J Child Psychol Psychiatry. 51(1):58-65.

Lucchini, RG, S Zoni, S Guazzetti, E Bontempi, S Micheletti, K Broberg, G Parrinello and DR Smith. 2012. Inverse association of intellectual function with very low blood lead but not with manganese exposure in Italian adolescents. Environmental Research

Toxicity Below 10 ug/dl - Mortality

Menke A, Muntner P, Batuman V, Silbergeld EK, Guallar E. Bloodlead below 0.48 mmol/L (10 mg/dL) and mortality among US adults. Circulation 2006;114:1388-94.

Detroit Blood Lead and School Outcomes


Children's Blood Lead Levels Also Display Strong Seasonal Variations With Peaks Generally in the Summer or Autumn When Soils Are Dry and Prone to Resuspension

A conceptual model of child BPb seasonal Pb poisoning is suggested. Lead from multiple sources has accumulated in soils of urban environments. The seasonal resuspension of Pb-contaminated soil in urban atmospheres appears to be controlled by soil moisture and climate fluctuations. This study (Laidlaw et al., 2005)indicates that higher urban atmospheric Pb loading rates are experienced during periods of low soil moisture and within areas of Pb-contaminated surface soils. Children and adults living in urban areas where surface soils are contaminated with Pb may become exposed through indoor and outdoor inhalation of Pb dust and ingestion of Pb deposited within homes and outdoor surfaces. Because resuspension of Pb from contaminated soil appears to be driving seasonal child BPb fluctuations, concomitantly, we suggest that Pb-contaminated soil in and of itself may be the primary driving mechanism of child BPb poisoning in the urban environment.

Link to source

Laidlaw et al.'s (2005) model used in the three cities above was independently replicated in Milwaukee, Wisconsin in an unpublished court case

Soil Lead is a Major Source of Atmospheric Lead via Soil Re-suspension

Weather adjusted air Pb and air soil over time, including median spline fits, for Pittsburgh, Detroit, Chicago and Birmingham.

Weather adjusted air lead versus air soil with linear fit for peak months (June, July, August, and September) and non peak months (October through May) for Pittsburgh, Detroit, Chicago and Birmingham combined.

This study also observed..."Atmospheric soil and lead aerosols are 3.15 and 3.12 times higher, respectively, during weekdays than weekends and Federal Government holidays, suggesting that automotive traffic turbulence plays a significant role in re-suspension of contaminated roadside soils and dusts."

Source - Mark A.S. Laidlaw, Sammy Zahran, Howard W. Mielke, Mark P. Taylor, Gabriel M. Filippelli. 2011. Atmospheric Environment.

Plot of Temporal Variation in Atmospheric Soil and Lead in Detroit - 2001-2009

Scatterplot with median splines of weather adjusted air lead and air soil in time (daily). Weather-adjusted air Pb and soil estimates (µg/m3) are graphed on the daily time-step, fitting distributions of air Pb and soil values with median splines.

Source - Zahran S., Laidlaw M.A.S., McElmurry S.P., Filippelli G.M. Taylor M. (2013)

Supplemental Material

Plot of Temporal Variation in Atmospheric Lead and Children's Blood Lead in Detroit - 2001-2009

Weather-adjusted air Pb (µg/m3) and blood Pb (µg/dL) by age group. Average monthly child blood Pb levels adjusted by local weather conditions, child gender, method of blood draw, and census tract fixed effects

Source - Zahran S., Laidlaw M.A.S., McElmurry S.P., Filippelli G.M. Taylor M. (2013)

Supplemental Material

Early Childhood Lead Exposure and Academic Achievement:Evidence From Detroit Public Schools, 2008–2010 (Zhang et al, 2013)

Rio-Salas et al. (2012) - Atmospheric Environment - Study of urban soil Pb re-suspension

My suggestion for what is occurring is that when the soil is resuspended, the fine fraction where the bulk of the petrol lead particles reside is suspended in the air. This fraction has a higher concentration than the bulk soil and also has a different isotopic signature (more anthropogenic) than the bulk soil.It is also suggested that air lead concentrations can result in very high concentrations at a height of two (m) in the summertime in cities where the soil lead concentrations are an order of magnitude higher than this Mexican city.It does not take much imagination to understand that air lead concentrations at two metres are at the same height as windows which likely results in air lead penetration into homes.

Source - Rio-Salas et al. (2012

Atmospheric Soils Are Resuspended With Peak Concentrations in the Summer and Autumn in the U.S.

It is believed that this process is resuspending urban lead contaminated soils in the summer and autumn.

The same summertime seasonality was observed for Total Suspended Particulates (TSP), Nickel, Iron and Sulfur in Esperance, Western Australia. Note summer in Esperance occcurs between November and February.

Link to Source

Washington DC Atmospheric Lead Seasonality

Link to Source

2.) Author:Nicholas E. Pingitore, Jr.1,2*, Juan W. Clague1, Maria A. Amaya2, Beata Maciejewska1, Jess J. Reynoso3
Title:Urban Airborne Lead: X-Ray Absorption Spectroscopy Establishes Soil as Dominant Source
Source: PLOS One Link

Despite the dramatic decrease in airborne lead over the past three decades, there are calls for regulatory limits on this potent pediatric neurotoxin lower even than the new (2008) US Environmental Protection Agency standard. To achieve further decreases in airborne lead, what sources would need to be decreased and what costs would ensue? Our aim was to identify and, if possible, quantify the major species (compounds) of lead in recent ambient airborne particulate matter collected in El Paso, TX, USA.

Methodology/Principal Findings: We used synchrotron-based XAFS (x-ray absorption fine structure) to identify and quantify the major Pb species. XAFS provides molecular-level structural information about a specific element in a bulk sample. Pb-humate is the dominant form of lead in contemporary El Paso air. Pb-humate is a stable, sorbed complex produced exclusively in the humus fraction of Pb-contaminated soils; it also is the major lead species in El Paso soils. Thus such soil must be the dominant source, and its resuspension into the air, the transfer process, providing lead particles to the local air.

Conclusions/Significance: Current industrial and commercial activity apparently is not a major source of airborne lead in El Paso, and presumably other locales that have eliminated such traditional sources as leaded gasoline. Instead, local contaminated soil, legacy of earlier anthropogenic Pb releases, serves as a long-term reservoir that gradually leaks particulate lead to the atmosphere. Given the difficulty and expense of large-scale soil remediation or removal, fugitive soil likely constrains a lower limit for airborne lead levels in many urban settings.

Urban Atmospheric Lead Is Associated with Particulate Matter Less Than 10 micron in Size (PM10)

Mexico City - 1991

Link to source

Blood Lead Seasonality

Note the blood lead seasonal patterns below. Whatever drives these seasonal blood lead changes is the major driving force of urban blood lead poisoning.

Unknown City

source- The Lead debate: the environment, toxicology and child health By Richard Lansdown, William Yule

Chicago, Illinois



Lansing, Michigan



Milwaukee,Wisconsin (USA)-New

Link to source

">Link to source

Milwaukee,Wisconsin (USA)-Old

USEPA Discussion - p. 45 "Exposure may increase in the summer because of factors that include increased outdoor playing time, more opening and closing of windows, increased hand-to-mouth activity, and drier leaded dust that more easily enters homes."

Link to source

Milwaukee Soil Lead Study

St. Louis,Missouri (USA)

Link to source

Link to Another St. Louis Source

What I found interesting about this study is that 78% of the blood lead poisoning in the St. Louis study comes from children aged two to three, and 56% of the cases occurred between June and September when sunshine was greatest. It would seem that if the Vitamin D hypothesis were true, there would not be age dependent peaks (which are well known to be caused by mouthing behaviour) and suggests that blood lead seasonality is externally driven rather than internally driven.

Birmingham, England

Link to source

Seasonality of Lead Loading in the Interior of a Northern England House


Blood Lead Seasonality in Buxton, England - 1972

Boston,Massachusetts (USA)

Link to source

USEPA state on page iV, ...."Modeled lead levels for air, floor dust and furniture dust all had peaks in July"

New York State, (USA)

Link to source

New York City Atmospheric Lead: 1970-1976

Link to source

New York City Blood Lead Seasonality: 1970-1976

Link to source

Note that the summertime atmospheric lead peaks coincided with the blood lead peaks. It is suggested that current blood lead peaks are also caused by exterior atmosperic lead summertime peaks.

Los Angeles, California (USA)

Link to source

Link to California Soil Lead Studies

Jersey City, New Jersey (USA)

State of New Jersey - 2000 to 2004 (USA)

New Jersey Department of Health and Senior Services Consumer and Environmental Health Services Environmental Public Health Tracking Project. 2007. Analysis of Risk Factors for Elevated Levels of Blood Lead in New Jersey Children, 2000-2004 Demonstration Project on Geographic Patterns of Childhood Blood Lead and Environmental Factors in New Jersey.

Baltimore, Maryland & New York City (USA)

Chicago, Illinois(USA)

New Haven, Connecticut(USA)


Homegrown Vegetables Are Another Exposure Pathway to Lead in Urban Soil

The recent movement towards cultivating homegrown vegetables, partly due to the global financial crisis, poses risks due to the uptake of lead in certain vegetables.

The following documents have been selected to educate the reader:

Garden Safe, Garden Well (Gabriel Filippelli, IUPUI)

2011 - Gardening and Lead Review Paper

Chicago Illinois Lead Uptake in Vegetables Study

Home Gardening in Lead Contaminated Soil

Gardening on Lead- and Arsenic-Contaminated Soils

Heavy metals contamination of home grown vegetables near metal smelters in NSW

Sustainable Gardening Information Page

Vegetable Consumption and Blood Lead Concentration

Eggs Laid in Urban Areas Can Be Contaminated with Lead

Solution - Remediation Precedent Set in New Orleans, Evansville and Omaha

1.) Method of Mielke et al.(2011) - New Orleans

"The soil emplacement was conducted by first spreading out a bright orange, water pervious geotextile material to cover the original soil of the play area. The geotextile layer prevents Pb-safe soil from mixing with the underlying original soil and acts as a warning layer to anyone digging into soil. Soil was not removed from the play areas in this project. The Pb-safe soil was from the Bonnet Carré Spillway, located up-river from New Orleans (U.S. ACE or Army Corps of Engineers). The alluvial soil, derived from the sediments of the Mississippi River at the Bonnet Carré Spillway, has a median Pb content of 5 mg/kg (Mielke et al., 2000). The Bonnet Carré soil was transported to the childcare center and emplaced on top of the geotextile layer to a depth of at least 15cm(6 inches)."


2.) USEPA Method - "dig and dump"(more costly than Mielke's Method)

EPA Region 7 Completes 10,000th Residential Yard Cleanup of Lead-Contaminated Soils at Omaha Lead Site in Omaha, Neb.

Jacobsville Neighborhood Lead Contamination Superfund Site Newsletter - May 2011

Soil lead exposure reduction in the inner cities will improve health, increase students cognitive abilities and provide jobs, perhaps to inner-city residents.

Simple Non-toxic Way Forward

1.) Cut lawn as low as possible 2.) Lay down Bright Orange Geotextile 3.) Terraseeding (soil and seed mix) -0r- 3.) Apply Topsoil Using Topsoil Slinger & 4.) Hydroseed During Spring


Geotextile link

Topsoil Slingers

Topsoil Slinger Video # 1

Topsoil Slinger Video # 2

Topsoil Slinger Video # 3

Topsoil Slinger Video # 4

Terraseeding (mix soil and grass seed)



Hydroseeder Video # 1

Soil Treatment Strategy

I recommend that soil covering efforts first be conducted in areas where there is a high prevalence of lead poisoning and where soil lead levels are high (triage). I would first focus on roadside soils (0-25m)within these areas and then continue until areas with high lead poisoning prevalence are covered (or funds permit).

Recommended Funding Mechanism To Cleanup Urban Soils

Small Gasoline Tax!

Call For Blood Lead Incidence Data Transparency

I strongly suggest that the new Obama government publish child blood lead incidence maps of the top 50 cities in the U.S by graphically displaying the location and all the blood lead concentrations (>5 ug/dl, > 10ug/dl and >20 ug/dl) for the previous 5 years, and updated yearly (see Detroit Blood Lead Incidence Map Above). The percentage of the children sampled should be boldly presented as well. These maps should be available for all to see on one central internet site. The website would be registered with all the major search engines so that anyone could locate the data. This data is already available and could easily be put together in a two month time period by someone experienced in GIS and the internet. The funding cost would be extremely small.

See Dot Maps of Children's Lead Poisoning in Various Wisconsin Cities

Call For National Urban Soil Geochemical Risk Mapping Program

I suggest that the Obama administration use the United States Geological Survey to conduct an urban soil geochemical risk mapping program in the 50 largest cities in the United States. I recommend the geochemical mapping methods be adopted fromthe British Geological Survey, David L Johnson/colleagues at SUNY-ESF or Howard Mielke and colleagues at Tulane/Xavier. The results should be placed online in one central location for anyone to view.

Additional Lead Thoughts

1.)The USEPA's 400 mg/kg soil guideline is not protective of human health. A safe guideline would be about 75 to 100 mg/kg. The California draft soil lead guideline is 80 mg/kgLink. The Minnesota (USA) soil lead guideline is 100 mg/kg and the Dutch guideline is 40 mg/kg. See the dose-response curves of Mielke and Johnson's soil lead-blood lead ecological study design above. Risk assessments that have argued to leave lead concentrations higher than 400 mg/kg (and higher than 100 mg/kg) are deeply flawed and these areas will have to be revisited when a lower guideline level is adopted by a bold USEPA, if that ever happens.

2.) There is a glaring disconnect between the actions of the USEPA and the CDC. While the USEPA is cleaning up 10's of thousands of lead contaminated yards in Omaha and Evansville under the Superfund program, the CDC does not have any money appropriated to the investigation and remediation of contaminated soil and continue with the paradigm that lead poisoning is caused primarily by lead paint. No money has been appropriated by either the USEPA or the CDC for the investigation and remediation of non-Superfund cities, of which many are just as contaminated as Omaha and Jacobsville

There are three basic things that can be done:

1) Do nothing (this is what the current approach is); 2) Remediate (cover soils/remove flaking paint & Pb lines); 3) Move children away from source area.

History of Lead

Kovarik W. Ethyl-leaded gasoline. How a classic occupational disease became an international public health disaster. Int J Occup Environ Health 2005;11:384-397.

CalTech Masters Thesis on Clair Patterson

Kitman - Secret History of Lead (summary)

Kitman - Secret History of Lead (full version)

Rosner, D., and G. Markowitz 2005. Standing up to the lead industry: An interview with Herbert Needleman. Publ Health Reports 120:330-7.

Markowitz, G., and D. Rosner 2002. Deceit and Denial: The Deadly Politics of Industrial Pollution. University of California Press.


Author:John L. Adgate, Robert D. Willis, Timothy J. Buckley, Judith C. Chow, John G. Watson, George G. Rhoads, and Paul J. Lioy
Title:Chemical Mass Balance Source Apportionment of Lead in House Dust
Journal:Environ. Sci. Technol., 32 (1), 108 -114, 1998.
Abstract: Chemical mass balance was used to apportion the major proximate contributors of lead mass to house dust (HDPb) obtained from urban Jersey City, NJ, homes of children at risk for lead exposure. Coarse (up to ~60 m) and PM10 (<10 m) particle size fractions of vacuum dust samples from 64 residences with lead-based paints were analyzed for Pb and 16 other elements. Source profiles were developed to represent proximate source media contributors to HDPb pre-1960 interior lead-based paints, indoor air, and a crustal source profile that accounted for the contribution of yard soils and street dusts. On average for both size fractions the exterior proximate sources, i.e., crustal materials and deposited airborne particulates, were responsible for approximately two-thirds of the HDPb mass; the interior lead-based paint sources contributed the remaining third. Results indicate considerable variability in Pb source contributors between homes, but little dif ference in the source contributors to the two overlapping size fractions within homes. Effective reduction of HDPb levels will require control of both exterior and interior sources.

Author:Angle Carol;McIntire Matilda
Title:Environmental lead and children: The Omaha study
Journal:Journal of Toxicology and Environmental Health Volume 5, Issue 5 September 1979 , pages 855 - 870
Abstract:Blood lead (Pb B) was determined in 1232 samples from 831 children in Omaha and correlated with air lead (Pb A) concentrations of 0.02-1.69 μg/m3 from 1971 to 1977. A bivariate equation for ages 6-18 yr based on these data predicts on increase in Pb B of 1.4 μg/dl as Pb A increases from 1 to 2 μg/m3. Pb B increases 7 μg/dl as the mean values for soil and house dust Pb increase from 100 to 750 μg/g. Multiple regression analysis shows that the combined effects of air, soil, and house dust Pb account for 21% of the variance of Pb B, with a high intercorrelation of all 3 variables. Since the variance of repeat sampling in individuals accounted for 38% of the total variance of Pb B, approximately 40% is unexplained and requires measurement of Pb from dietary and other sources.

Reference Type: Journal Article
Record Number: 14
Author: Alonso, E.; Cambra, K.; Martinez, T.
Year: 2001
Title: Lead and cadmium exposure from contaminated soil among residents of a farm area near an industrial site
Journal: Archives of Environmental Health. 56(3)
Volume: 56(3)
Pages: 278-82
Accession Number: 11480506
Abstract: In this study, the authors determined the degree of lead and cadmium exposure in a population that resided in an area with contaminated soil. The extent of exposure from soil pollution was also assessed. Lead and cadmium concentrations in blood of children and adults who resided in the contaminated area were measured, and cadmium concentration in urine of adults was also determined. An adult control group was recruited from a nonpolluted area. The mean blood lead level in adults who resided in the polluted area was 9.8 microg/dl, compared with a mean level of 6.8 microg/dl in controls (p = .004). Urinary cadmium levels were well below the level associated with onset of symptoms, but the differences between levels in residents of the contaminated area (0.54 microg/gm creatinine) and levels in the controls (0.37 microg/gm creatinine) indicated that life-long cadmium exposure had been higher among the residents of the contaminated area (p = .086). The mean blood lead level and mean blood cadmium level in children were 5.2 microg/dl (maximum = 7.90 microg/dl) and 0.10 microg/l, respectively. Lead in soil accounted in large part for the differences in blood lead levels in children; however, blood cadmium levels were not associated with soil cadmium levels, but, rather, with consumption of home-grown vegetables.
Journal Article

Reference Type: Journal Article
Record Number: 81
Author: Angle, C. R.; McIntire, M. S.
Title: Environmental lead and children: the Omaha study
Journal: Journal of Toxicology & Environmental Health.
Volume: 5(5)
Pages: 855-70.
Accession Number: 583166
Abstract: Blood lead (Pb B) was determined in 1232 samples from 831 children in Omaha and correlated with air lead (Pb A) concentrations of 0.02-1.69 microgram/m3 from 1971 to 1977. A bivariate equation for ages 6-18 yr based on these data predicts an increase in Pb B of 1.4 microgram/dl as Pb A increases from 1 to 2 microgram/m3. Pb B increases 7 microgram/dl as the mean values for soil and house dust Pb increase from 100 to 750 microgram/g. Multiple regression analysis shows that the combined effects of air, soil, and house dust Pb account for 21% of the variance of Pb B, with a high intercorrelation of all 3 variables. Since the variance of repeat sampling in individuals accounted for 38% of the total variance of Pb B, approximately 40% is unexplained and requires measurement of Pb from dietary and other sources.
Journal Article

Reference Type: Journal Article
Record Number: 58
Author: Aschengrau, A.; Beiser, A.; Bellinger, D.; Copenhafer, D.; Weitzman, M.
Title: The impact of soil lead abatement on urban children's blood lead levels: phase II results from the Boston Lead-In-Soil Demonstration Project
Pages: 125-48, 1994 Nov.
Accession Number: 7982389
Abstract: The Boston Lead-In-Soil Demonstration Project was a randomized environmental intervention study of the impact of urban soil lead abatement on children's blood lead levels. Lead-contaminated soil abatement was associated with a modest reduction in children's blood lead levels in both phases of the project; however, the reduction in Phase II was somewhat greater than that in Phase I. The combined results from both phases suggest that a soil lead reduction of 2060 ppm is associated with a 2.25 to 2.70 micrograms/dl decline in blood lead levels. Low levels of soil recontamination 1 to 2 years following abatement indicate that the intervention is persistent, at least over the short-term. Furthermore, the intervention appears to benefit most children since no measurable differences in efficacy were observed for starting blood and soil lead level, race, neighborhood, gender, and many other characteristics. However, soil abatement did appear to be more beneficial to children in the higher socioeconomic classes, with low baseline ferritin levels, and who spent time away from home on a regular basis and lived in nonowner occupied housing, and with adults who had lead-related hobbies and almost always washed their hands before meals. Children who lived in apartments with consistently elevated floor dust lead loading levels derived almost no benefit from the soil abatement. It was not possible to separate the effects of the variables that had a beneficial impact on efficacy because they were closely correlated and the number of subjects was small. We recommend that further research be conducted to identify subgroups of children to whom soil lead abatement might be targeted.
Notes: Environmental Research. 67(2)
Clinical Trial
Clinical Trial, Phase II
Journal Article
Randomized Controlled Trial

Reference Type: Journal Article
Record Number: 39
Author: Aschengrau, A.; Beiser, A.; Bellinger, D.; Copenhafer, D.; Weitzman, M.
Year: 1997
Title: Residential lead-based-paint hazard remediation and soil lead abatement: their impact among children with mildly elevated blood lead levels
Journal: American Journal of Public Health.
Volume: 87(10)
Pages: 1698-702.
Accession Number: 9357358
Abstract: OBJECTIVES: This prospective study describes the impact of residential lead-based-paint hazard remediations on children with mildly elevated blood lead levels. METHODS: Changes in blood lead levels were observed following paint hazard remediation alone and in combination with soil abatement. RESULTS: After adjustment for the confounding variables paint hazard remediation alone was associated with a blood lead increase of 6.5 micrograms/dL (P = 0.5), and paint hazard remediation combined with soil abatement was associated with an increase of 0.9 microgram/dL (P = 36). CONCLUSIONS: Lead-based-paint hazard remediation as performed in this study, is not an effective secondary prevention strategy among children with mildly elevated blood lead levels.
Notes: Journal Article

Reference Type: Journal Article
Record Number: 53
Author: Bates, M.; Malcolm, M.; Wyatt, R.; Garrett, N.; Galloway, Y.; Speir, T.; Read, D.
Year: 1995
Title: Lead in children from older housing areas in the Wellington region
Journal: New Zealand Medical Journal.
Volume: 108(1009).
Pages: 400-4.
Accession Number: 7478332
Abstract: AIMS. To examine blood lead levels in children, aged 12 to 23 months, living in old housing areas of Wellington and Lower Hutt, and to investigate risk factors for high lead levels. METHOD. Children were selected from Plunket Society rolls. Venous blood samples were collected, and care givers were interviewed with a questionnaire. Soil samples were taken from around the children's homes. Both soil and blood samples were analysed for lead content. RESULTS. Blood samples and completed questionnaires were obtained for 143 children. The geometric mean blood lead level for all the children was 0.25 mumol/L (5.1 micrograms/dL) (95% confidence interval [95% CI]: 0.22-0.28 mumol/L). Three children had blood lead levels that exceeded the level for notification in New Zealand 1.45 mumol/L and a further 13 had blood lead levels exceeding 0.48 mumol/L. Children with elevated lead levels were likely to live in a house greater than 50 years old where paint removal had taken place in the last 2 years (risk ratio [RR] = 14.4, 95% CI: 2-107). Eating dirt, particularly for children who usually played outside within 2 metres of the house, was also a risk factor for elevated blood lead levels. Soil lead levels generally increased with the age of the house and were weakly correlated with blood lead levels (r = 0.32). CONCLUSION. Paint removal in old houses is a major risk factor for elevated blood lead levels. However, the number of study children living in houses less than 50 years old was limited. Because of this and possible participant selection bias, the results of this study require confirmation in a separate population-based study. Information about the specific paint removal procedures that cause high lead levels is also needed.

<Author: Michael E. Beard and S.D. Allen. 1995.
Title:Lead in Paint, Soil, and Dust: Health Risks, Exposure Studies, Control Measures, Measurement Methods, and Quality Assurance. ASTM STP 1226. Philadelphia: American Society for Testing and Materials.

Author: Binns HJ, Gray KA, Chen T, Finster ME, Peneff N, Schaefer P, Ovsey V, Fernandes J, Brown M, Dunlap B.
Title:Evaluation of landscape coverings to reduce soil lead hazards in urban residential yards: The Safer Yards Project.
Abstract:This study was designed primarily to evaluate the effectiveness of landscape coverings to reduce the potential for exposure to lead-contaminated soil in an urban neighborhood. Residential properties were randomized in to three groups: application of ground coverings/barriers plus placement of a raised garden bed (RB), application of ground coverings/barriers only (no raised bed, NRB), and control. Outcomes evaluated soil lead concentration (employing a weighting method to assess acute hazard soil lead [areas not fully covered] and potential hazard soil lead [all soil surfaces regardless of covering status]), density of landscape coverings (6 = heavy, > 90% covered; 1 = bare, < 10% covered), lead tracked onto carpeted entryway floor mats, and entryway floor dust lead loadings. Over 1 year, the intervention groups had significantly reduced acute hazard soil lead concentration (median change: RB, -478 ppm; NRB, -698 ppm; control, +52 ppm; Kruskal-Wallis, P = 0.02), enhanced landscape coverings (mean change in score: RB, +0.6; NRB, +1.5; control, -0.6; ANOVA, P < 0.001), and a 50% decrease in lead tracked onto the floor mats. The potential hazard soil lead concentration and the entryway floor dust lead loading did not change significantly. Techniques evaluated by this study are feasible for use by property owners but will require continued maintenance. The long-term sustainability of the method needs further examination.
SourceEnviron Res. 2004 Oct;96(2):127-38.

Reference Type: Journal Article
Author: Boreland F, Lyle DM.
Year: 2006
Title: Lead dust in Broken Hill homes: effect of remediation on indoor lead levels.
Journal: Environ Res.
Volume: 100(2)
Pages: 276-83
Abstract:This study was undertaken to determine whether home remediation effectively reduced indoor lead levels in Broken Hill, a long-established silver-lead-zinc mining town in outback Australia. A before-after study of the effect of home remediation on indoor lead levels was embedded into a randomized controlled trial of the effectiveness of remediation for reducing elevated blood lead levels in young children. Moist towelettes were used to measure lead loading (microg/m2) on internal windowsills and internal and entry floors of 98 homes; samples were collected before, immediately after, and 2, 4, 6, 8, and 10 months after remediation. Data were log(10) transformed for the analysis. Remediation reduced average indoor lead levels by approximately 50%, and lead levels remained low for the duration of the follow-up period (10 months). The greatest gains were made in homes with the highest initial lead levels; homes with low preremediation lead levels showed little or no benefit. Before remediation, homes located in areas with high soil lead levels or with "poor" dust proofing had higher lead levels than those in areas with lower soil lead levels or with "medium" or "good" dust proofing; these relative differences remained after remediation. There was no evidence that lead loading was reduced by an increased opportunity to become aware of lead issues. We conclude that remediation is an effective strategy for reducing the lead exposure of children living in homes with high indoor lead levels.

Author:Campbell C, Schwarz DF, Rich D, Dockery DW. 2003. Effect of a follow-up professional home cleaning on serial dust and blood lead levels of urban children. Arch Environ Health. Dec;58(12):771-80.
Abstract:Children residing in Philadelphia, Pennsylvania, who were enrolled in a clinical trial of oral chelation therapy (n=73) were studied to determine the effects of a follow-up professional lead dust cleaning of their homes 18 mo after an initial cleaning and commencement of therapy. Home dust lead levels were determined from dust-wipe specimens collected from the kitchen and playroom floors, and from a playroom windowsill, prior to, immediately following, and 3 and 6 mo after the second cleaning. Children's blood lead levels were assessed at 3-mo intervals before and after the follow-up cleaning. Professional cleaning produced immediate decreases in dust lead levels; however, dust lead re-accumulated to precleaning levels within 3-6 mo. Frequent, repeated cleanings may be required if blood lead or dust lead levels are to be reduced and sustained at low levels in urban homes.

Author:Caravanos, Jack, Weiss, Arlene and Jaeger, Rudolph. 2005. An exterior and interior leaded dust deposition survey in New York City: Results of a 2-year study. Environmental Research. Abstract: Environmental concentrations of leaded dust were monitored by weekly sample collection of interior and exterior settled dust that had accumulated due to atmospheric deposition. The weekly deposition amounts were measured and the cumulative rates of lead in dust that deposited on a weekly basis over 2 year's time were determined. The sampling analysis revealed that the median values of leaded dust for the interior plate (adjacent to the open window), unsheltered exterior plate, and the sheltered exterior plate were 4.8, 14.2, and 32.3 g/feet2/week, respectively. The data supports the existence of a continuous source of deposited leaded dust in interior and exterior locations within New York City. Additional data from a control plate (interior plate with the window closed) demonstrate that the source of the interior lead deposition was from exterior (environmental) sources. Because of the ubiquitous nature of lead in our environment and the toxic threat of lead to the cognitive health of children, this data provides a framework for the understanding of environmental exposure to lead and its potential for continuing accumulation within an urban environment.

Author:Caravanos, Jack, Blaise, Marc. J., Weiss, Arlene and Jaeger, Rudolph. 2005. A survey of spatially distributed exterior dust lead loadings in New York City Abstract: This work documents ambient lead dust deposition values (lead loading) for the boroughs of New York City in 2003-2004. Currently, no regulatory standards exist for exterior concentrations of lead in settled dust. This is in contrast to the clearance and risk assessment standards that exist for interior residential dust. The reported potential for neurobehavioral toxicity and adverse cognitive development in children due to lead exposure prompts public health concerns about undocumented lead sources. Such sources may include settled dust of outdoor origin. Dust sampling throughout the five boroughs of NYC was done from the top horizontal portion of pedestrian traffic control signals (PTCS) at selected street intersections along main thoroughfares. The data (n=214 samples) show that lead in dust varies within each borough with Brooklyn having the highest median concentration (730 g/ft2), followed in descending order by Staten Island (452 g/ft2), the Bronx (382 g/ft2), Queens (198 g/ft2) and finally, Manhattan (175 g/ft2). When compared to the HUD/EPA indoor lead in dust standard of 40 g/ft2, our data show that this value is exceeded in 86% of the samples taken. An effort was made to determine the source of the lead in the dust atop of the PTCS. The lead in the dust and the yellow signage paint (which contains lead) were compared using isotopic ratio analysis. Results showed that the lead-based paint chip samples from intact signage did not isotopically match the dust wipe samples taken from the same surface. We know that exterior dust containing lead contributes to interior dust lead loading. Therefore, settled leaded dust in the outdoor environment poses a risk for lead exposure to children living in urban areas, namely, areas with elevated childhood blood lead levels and background lead dust levels from a variety of unidentified sources.

Author:Leticia Carrizalesa, Israel Razoa, Jess I. Tllez-Hernndeza, Roco Torres-Nerioa, Arturo Torresa, Lilia E. Batresa, Ana-Cristina Cubillasb and Fernando Daz-Barrigaa,
Title:Exposure to arsenic and lead of children living near a copper-smelter in San Luis Potosi, Mexico: Importance of soil contamination for exposure of children
Abstract:The objective of this study was to assess the levels of soil contamination and child exposure in areas next to a primary smelter (arsenic copper metallurgical) located in the community of Morales in San Luis Potosi, Mexico. In Morales, 90% of the soil samples studied in this work were above 400 mg/kg of lead, and above 100 mg/kg of arsenic, which are guidelines recommended by the United States Environmental Protection Agency (EPA). Bioaccessibility of these metals was studied in vitro in 10 soil samples; the median values of bioaccessibility obtained in these samples were 46.5% and 32.5% for arsenic and lead. Since the concentrations of arsenic and lead in soil were above normal values, and taking into account the bioaccessibility results, exposure to these metals was evaluated in children. Regarding lead, children aged 3-6 years had the highest mean blood lead levels; furthermore, 90% of them had concentrations above 10 μg/dl (CDC's action level). Total urinary arsenic was higher in children aged 8-9 yr; however, the percentage of children with concentrations above 50 μg/g creatinine (CDC's action level) or 100 μg/g creatinine (World Health Organization [WHO] action level) was similar among different age groups. Using the EPAs integrated exposure uptake biokinetic model for lead in children (IEUBK), we estimated that 87% of the total lead in blood is obtained from the soil/dust pathway. The exposure dose to arsenic, estimated for the children living in Morales using Monte Carlo analysis and the arsenic concentrations found in soil, was above the EPA's reference dose. With all these results, it is evident that studies are needed in order to identify adverse health effects in children living in Morales; nevertheless, it is more important to develop a risk reduction program as soon as possible.
Notes:Environmental Research Volume 101, Issue 1 , May 2006, Pages 1-10

Reference Type: Journal Article
Record Number: 79
Author: Charney, E.; Sayre, J.; Coulter, M.
Title: Increased lead absorption in inner city children: where does the lead come from?
Pages: 226-31, 1980 Feb.
Accession Number: 7354967
Abstract: Pica for lead-containing paint has been questioned as the principal mechanism for the widespread moderately elevated blood lead levels (30 to 80 microgram/100 ml) in inner city children. This study explored the hypothesis that lead-contaminated household dust is a major source of lead for these children; hand contamination and repetitive mouthing is the proposed mechanism of ingestion. Forty-nine inner city children with blood lead 40 to 70 microgram/100 ml were matched with 50 children with blood lead less than or equal to 29 microgram/100 ml from the same inner city environment. House dust lead and lead on hands were found in significantly greater quantity among experimental subjects. Other factors differed between groups; lead content of peeling paint, soil lead, and pica affected more experimental than control children, but did not account for more than 50% of experimental cases. The cause of moderate blood lead elevation is multifactoral: no single source accounted for all children with elevated levels. However, lead contamination of house dust and hands appears to be a major factor in this condition.
Notes: Pediatrics. 65(2)
Journal Article

Reference Type: Journal Article
Record Number: 42
Author: Cikrt, M.; Smerhovsky, Z.; Blaha, K.; Nerudova, J.; Sediva, V.; Fornuskova, H.; Knotkova, J.; Roth, Z.; Kodl, M.; Fitzgerald, E.
Title: Biological monitoring of child lead exposure in the Czech Republic
Pages: 406-11, 1997 Apr.
Accession Number: 9189705
Abstract: The area around the Pribram lead smelter has been recognized to be heavily contaminated by lead (Pb). In the early 1970s, several episodes of livestock lead intoxication were reported in this area; thereafter, several epidemiological and ecological studies focused on exposure of children. In contrast to earlier studies, the recent investigation (1992-1994) revealed significantly lower exposure to lead. From 1986-1990, recorded average blood lead levels were about 37.2 micrograms lead (Pb)/100 ml in an elementary school population living in a neighborhood close to the smelter (within 3 km of the plant). The present study, however, has found mean blood lead levels of 11.35 micrograms/100 ml (95% CI = 9.32; 13.82) among a comparable group of children. In addition to blood lead, tooth lead was used to assess exposure among children. Statistically significant differences (p < 0.05) were observed between the geometric mean tooth lead level of 6.44 micrograms Pb/g (n = 13; 95% CI = 3.95; 10.50) in the most contaminated zone and 1.43 micrograms Pb/g (n = 35; 95% CI = 1.11; 1.84) in zones farther away from the point source. Both biomarkers, blood and tooth lead levels, reflect a similar pattern of lead exposure in children. This study has attempted a quantitative assessment of risk factors associated with elevated lead exposure in the Czech Republic. Content of lead in soil, residential distance from the smelter, consumption of locally grown vegetables or fruits, drinking water from local wells, the mother's educational level, cigarette consumption among family members, and the number of children in the family were factors positively related (p < 0.05) to blood lead levels. The resulting blood lead level was found to be inversely proportional to the child's age.
Notes: Environmental Health Perspectives. 105(4)
Journal Article

Author:Heather F. Clark, Daniel J. Brabander and Rachel M. Erdil
Title:Sources, Sinks, and Exposure Pathways of Lead in Urban Garden Soil
Abstract:The chemistry of Pb in urban soil must be understood in order to limit human exposure to Pb in soil and produce and to implement remediation schemes. In inner-city gardens where Pb contamination is prevalent and financial resources are limited, it is critical to identify the variables that control Pb bioavailability. Field-portable X-ray fluorescence was used to measure Pb in 103 urban gardens in Roxbury and Dorchester, MA, and 88% were found to contain Pb above the USEPA reportable limit of 400 mg/kg. Phosphorus, iron, loss on ignition, and pH data were collected, Pb-bearing phases were identified by X-ray diffraction, and Pb isotopes were measured using inductively coupled plasma mass spectrometry. Four test crops were grown both in situ and in Roxbury soil in a greenhouse, and plant tissue was analyzed for Pb uptake by polarized energy-dispersive X-ray fluorescence. Variation at the neighborhood scale in soil mineralogical and chemical characteristics suggests that the bioavailable fraction of Pb in gardens is site specific. Based on Pb isotope analysis, two historical Pb sources appear to dominate the inventory of Pb in Roxbury gardens: leaded gasoline (207 Pb/206 Pb = 0.827) and Pb-based paint (207Pb/206 Pb = 0.867). Nearly 70% of the samples analyzed can be isotopically described by mixing these two end members, with Pb-based paint contributing 40 to 80% of the mass balance. A simplified urban human exposure model suggests that the consumption of produce from urban gardens is equivalent to approximately 10 to 25% of children's daily exposure from tap water. Furthermore, analysis of over 60 samples of plant tissue from the four test species suggests that in these urban gardens unamended phytoremediation is an inadequate tool for decreasing soil Pb.
Notes:J Environ Qual 35:2066-2074 (2006), DOI: 10.2134/jeq2005.0464

Author:Clark S, Menrath W, Chen M, Succop P, Bornschein R, Galke W, Wilson J.
Abstract:To aid in understanding the contribution of exterior dust/soil lead to postintervention interior dust lead, a subset of housing from the HUD Lead-Based Paint Hazard Control Grant Program Evaluation was selected for study. Housing from 12 state and local governments was included. Exterior entry and street dust samples were obtained by a vacuum method, and soil samples were building perimeter core composites. Interior dust wipe lead data (microg/ft(2)) and paint lead data (mg/cm(2)) were also available for each of the dwelling units and included in the modeling. Results from 541 dwelling units revealed a wide range of exterior dust and soil lead levels, within and between grantees. Minimum and maximum geometric mean lead levels, by grantee, were 126 and 14400 microg/ft(2) for exterior entry dust; 325 and 4610 microg/ft(2) for street dust; and, for soil concentration, 383 and 2640 ppm. Geometric mean exterior entry dust lead concentration (1641 ppm) was almost four times as high as street dust lead concentration (431 ppm), suggesting that lead dust near housing was often a source of street dust lead. Geometric mean exterior entry dust lead loading was more than four times as high as window trough dust lead loading and more than an order of magnitude higher than interior entry dust lead loading. Statistical modeling revealed pathways from exterior entry dust lead loading to loadings on interior entryway floors, other interior floors, and windowsills. Paint lead was found to influence exterior entry dust lead. Results of this study show that housing where soil lead hazard control activities had been performed had lower postintervention exterior entry, interior entry floor, windowsills, and other floor dust loading levels. Soil was not present for almost half the buildings. Statistical analysis revealed that exterior strategy influenced soil lead concentration, and soil lead concentration influenced street dust lead loading. This study represents one of the few where an impact of soil treatments on dust lead levels within the housing has been documented and may represent the first where an impact on exterior entry dust lead has been found. The inclusion of measures to mitigate the role of exterior sources in lead hazard control programs needs consideration.
Notes:J Occup Environ Hyg. 2004 May;1(5):273-82.

Author:Culbard E, Thornton I, Watt J, Wheatley, M, Moorcroft S, Thompson M. 1988. Metal contamination in British urban dusts and soils. J Environ Qual 17:226-234.

Reference Type: Journal Article
Record Number: 55
Author: Devey, P.; Jingda, L.
Title: Soil lead levels in parks and playgrounds: an environmental risk assessment in Newcastle
Pages: 189-92, 1995 Apr.
Accession Number: 7786947
Abstract: In June 1993 the National Health and Medical Research Council set a national goal for blood lead of below 10 micrograms/dl. There is a need to know if the lead contamination of the urban environment is so high as to put community health at risk. Decisions, including whether soil should be removed and replaced, will have to be made. During the second half of 1993, an environmental assessment of lead contamination of soil within the City of Newcastle was conducted. Samples, 108 from surface soil and 10 from subsurface soil, were taken from public parks and playgrounds in the city area and analysed for lead content. The proportion within and the proportion above the guidelines for soil contamination were reported. Lead concentrations ranged from 25 to 2400 parts per million (ppm); 21 per cent of samples had concentrations higher than the 300 ppm action level, and the geometric mean was 134 ppm. Both the range and the average lead levels were typically no more than, or were even less than, soil lead levels documented for other cities in Australia, the United States and United Kingdom. Although each sampling site was noted, it was not our intention to focus in on individual sites. Indeed, to draw health-risk implications from any one result may be misleading and inaccurate. The results indicated moderate lead contamination of soil that could be controlled by regular top-dressing of soils, the use of bark chip on playground surfaces and by government initiatives aimed at lowering lead levels in petrol.
Notes: Australian Journal of Public Health. 19(2)
Journal Article

Author: Dixon SL, McLaine P, Kawecki C, Maxfield R, Duran S, Hynes P, Plant T.
Title:The effectiveness of low-cost soil treatments to reduce soil and dust lead hazards: The Boston lead safe yards low cost lead in soil treatment, demonstration and evaluation. Abstract:The Boston lead safe yards low cost lead in soil treatment, demonstration, and evaluation was developed to explore the viability and effectiveness of low-cost soil interventions to reduce exposure to soil lead hazards. Buildings that had been abated for lead to Massachusetts's deleading standards in the previous 5yrs and met other program requirements were recruited for the evaluation. Following individual property assessments, yards were treated with application of ground coverings and ground barriers in 2000-2001 and followed up at 1yr. The treatment cost ranged from $1095 to $5643 with an average of $2798. Soil lead levels at the building dripline, measured with a field-portable X-ray fluorescence analyzer (Niton Model 702 Spectrum Analyzer), dropped from 2021PPM at baseline to 206PPM at 1-yr follow-up. Most of the barrier treatments continued to block access to the lead-contaminated soil at 1yr. At the follow-up, few properties with grass treatment had areas that were completely bare, but 28% had more than a small amount of treated areas bare. Treatments were effective in reducing entryway dust lead in the rear of the building if the residents reported they had maintained the yard treatments. Each additional yard work activity reported was predicted to lower 1-yr floor dust lead loading at the rear common/main and dwelling unit entries by about 20%. Each additional 100ft(2) of yard treated was predicted to lower 1-yr floor dust loading at the rear dwelling unit entry by 19%. Treatments did not show a dust lead effect at 1yr in the front entryway of the building, but the investigators believe that this may be due to the effect of resident cleaning overshadowing the treatment effect. Notes: Environ Res. 2006 Feb 23; [Epub ahead of print]

Author:Duggan MJ.
Title:Contribution of lead in dust to children's blood lead
Abstract:The importance of urban dust as a source of lead for young children is still disputed. Although blood-lead data from various population surveys usually show a peak concentration in early childhood, there is evidence that such a peak is small or absent altogether in children without much access to the general environment. An examination of those studies where groups of people in regions of low and high lead contamination have been compared shows that the child/adult blood-lead ratio is almost always enhanced in the more exposed groups. This implies a route of lead uptake which is important for children but less so for adults, and it is likely that this route is the dust-hand-mouth one. There are sufficient data to suggest a quantitative relationship between raised levels of blood lead and lead in dust. There is a strong case for a lead-in-dust standard but some will probably remain unpersuaded unless or until there are reliable data for blood lead and environmental lead involving matched groups of young people from urban and rural areas.
Source:Environ Health Perspect. 1983 Apr;50:371-81.

Link to Paper

Reference Type: Journal Article
Record Number: 56
Author: Elhelu, M. A.; Caldwell, D. T.; Hirpassa, W. D.
Title: Lead in inner-city soil and its possible contribution to children's blood lead
Pages: 165-9, 1995 Mar-Apr.
Accession Number: 7786053
Abstract: This study was designed to assess distribution and sources of lead in inner-city soils in Washington, D.C. Duplicate soil samples were collected randomly from 239 unpaved front yards of homes in Washington, D.C. Soil samples were collected 1 m from the houses. Lead concentration in soil was determined by flame atomic absorption spectrophotometry. Presence of lead detected in soil was correlated and traced to the anticipated source of origin. A significantly high concentration of lead was present in inner-city soils. Areas of the city in which the highest lead concentrations were found (Wards 1, 4, 5, 6, 7, 8) were determined to contain a large number of residents who had attained lower education levels than most residents in the remaining wards. It was concluded that lead concentration in inner-city soil plays a significant role in the incidence of lead poisoning in children in the District of Columbia and that paint is the main source of soil lead. Demographic characteristics of the residents appeared to enhance the distribution of lead poisoning.
Notes: Archives of Environmental Health. 50(2)
Journal Article

Reference Type: Journal Article
Record Number: 73
Author: Elwood, P. C.
Title: The sources of lead in blood: a critical review
Pages: 1-23, 1986 Jun.
Accession Number: 3523752
Notes: Review
Science of the Total Environment. 52(1-2)
Journal Article

Reference Type: Journal Article
Record Number: 63
Author: Fett, M. J.; Mira, M.; Smith, J.; Alperstein, G.; Causer, J.; Brokenshire, T.; Gulson, B.; Cannata, S.
Title: Community prevalence survey of children's blood lead levels and environmental lead contamination in inner Sydney.[see comment]
Pages: 441-5, 1992 Oct 5.
Accession Number: 1406391
Abstract: OBJECTIVE: To determine the distribution of blood lead levels in preschool children in inner Sydney and identify possible sources of environmental lead. DESIGN: Cross sectional community based prevalence survey of children and the houses in which they live, and a survey of volunteer children. SETTING: Mort Bay and Summer Hill, residential localities in inner Sydney. PARTICIPANTS: Ninety-five children aged 9-48 months able to be identified in a defined geographic area and 63 children aged 9-48 months volunteered by their parents. OUTCOME MEASURES: Concentrations of lead in venous blood of all children and in samples from the home environment of Mort Bay children. RESULTS: Four of the children (2.5%) had blood lead levels > or = 1.21 mumol/L (25 micrograms/dL, the current Australian threshold of concern), 27 (17.1%) had levels > or = 0.72 mumol/L (15 micrograms/dL, the new US threshold for individual intervention) and 80 (50.6%) had levels > or = 0.48 mumol/L (10 micrograms/dL, the new US threshold for community intervention). Blood lead concentrations were significantly correlated with concentrations of lead in "sink" soil (r = 0.555, P = 0.026), play area soil (r = 0.492, P = 0.016) and dust from vacuum cleaners (r = 0.428, P = 0.05), and with age of child (r = -0.182, P = 0.023). The presence of the child during house renovation was a strong predictor of having a blood lead level above 0.72 mumol/L (15 micrograms/dL) (odds ratio, 4.6; 95% confidence interval, 1.8-11.7, P = 0.001). CONCLUSIONS: Lead in soil and in household dust in older areas of Sydney is likely to represent a significant health hazard to young children. Many thousands of children may be affected in Sydney and other Australian cities. There is an urgent need for expanded prevalence surveys, public education and the development of strategies for the abatement of lead in urban environments.
Notes: Medical Journal of Australia. 157(7)
Journal Article

Author: Filippelli, Gabriel M., Laidlaw, Mark A.S,
Title: The Elephant in the Playground: confronting lead-contaminated soils as an important source of lead burdens to urban populations
Reference: Perspectives in Biology and Medicine. volume 53, number 1 (winter 2010):31-45.
abstract: Although significant headway has been made over the past 50 years in understanding and reducing the sources and health risks of lead, the incidence of lead poisoning remains shockingly high in urban regions of the United States.At particular risk are poor people who inhabit the polluted centers of our older cities without the benefits of adequate nutrition, education, and access to health care.To provide a future with fewer environmental and health burdens related to lead,we need to consider the multiple pathways of lead exposure in children, including their continued contact with dust derived from inner-city soils.Recent research into the causes of seasonal variations in blood-lead levels among children has confirmed the importance of soil in lead exposure. Capping lead-contaminated soil with lead-free soil or soil amendment appears to be a simple and cost-effective way to reduce the lead load for urban youth.

Link to Paper

Author Filippelli, Gabriel M., Laidlaw, Mark A.S., Latimer, Jennifer C., Raftis, Robyn Urban Lead Poisoning and Medical Geology: An Unfinished Story GSA Today 2005 15: 4-11
ABSTRACT: The intersection between geological sciences and human health, termed medical geology, is gaining significant interest as we understand more completely coupled biogeochemical systems. An example of a medical geology problem largely considered solved is that of lead (Pb) poisoning. With aggressive removal of the major sources of Pb to the environment, including Pb-based paint, leaded gasoline, and lead pipes and solder, the number of children in the United States affected by Pb poisoning has been reduced by 80%, down to a current level of 2.2%. In contrast to this national average, however, about 15% of urban children exhibit blood Pb levels above what has been deemed safe (10 ug per deciliter); most of these are children of low socioeconomic-status minority groups. We have analyzed the spatial relationship between Pb toxicity and metropolitan roadways in Indianapolis and conclude that Pb contamination in soils adjacent to roadways, the cumulative residue from the combustion of leaded gasoline, is being remobilized. Developing strategies to remove roadway Pb at the source is a matter of public health and social justice, and constitutes perhaps the final chapter in this particular story of medical geology.

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Reference Type: Journal Article
Record Number: 60
Author: Gagne, D.
Title: Blood lead levels in Noranda children following removal of smelter-contaminated yard soil
Pages: 163-6, 1994 May-Jun.
Accession Number: 7922959
Abstract: In 1979, children two to five years of age living in Rouyn-Noranda, QC, in an urban district located within 1 km from a copper smelter had mean (geometric) blood lead levels (BLL) of 21 micrograms/dL. Afterwards, stack emissions were lowered. In 1989, mean (geom.) BLL were reduced to 11 micrograms/dL; 50% of the district children had BLL less than 10 micrograms/dL. In 1990-91, a $3 million top soil removal operation took place; residential lots having more than 500 ppm soil lead were decontaminated. In 1991, BLL were reduced to 7 micrograms/dL; 75% of the children had less than 10 micrograms/dL. Geographic analysis of the 1991 results showed that children with the highest BLL lived nearest to the smelter, where atmospheric dustfall to the ground reached 36 mg/m2/month. Follow-up pediatric blood lead campaigns are planned in 1993 and 1995, to evaluate the effects of an ongoing program for further reduction of atmospheric smelter emissions.
Notes: Canadian Journal of Public Health. Revue Canadienne de Sante Publique. 85(3)
Journal Article

Reference Type: Journal Article
Record Number: 26
Author: Gao, W.; Li, Z.; Wang, Z.; Wang, N.; Zhao, X.; Chen, Y.
Title: [Effects of environmental lead exposure in kindergartens on children's blood lead level]
Pages: 272-4, 1999 Sep.
Accession Number: 11864489
Abstract: OBJECTIVE: To determine if kindergartens' environmental status can influence children's lead exposure. METHODS: Environmental specimens, such as floor dust, peeled-off paint chip, soil and drinking water, as well as children's hand dust and blood samples, were collected and measured for their lead levels in 19 kindergartens, to analyze the relationship between children's blood lead levels and their environmental lead exposure. RESULTS: Geometric means of lead concentrations in indoor floor dust, peeled-off paint chip, dust fallout, outdoor floor dust, soil and drinking water were 86.5 microg/m(2), 235.5 microg/g, 445.9 microg/g, 172.4 microg/m(2), 70.1 microg/g and 12.5 microg/L, respectively. Lead level on children's hands averaged 3.4 microg at both hands. Blood lead levels in children correlated positively with the lead concentrations of outdoor floor dust and their hand dust, with correlation coefficients of 0.5186 and 0.2206, respectively. Multiple regression analysis showed that hand dust lead level in children entered the regression model with a largest standardized partial regression coefficient of 0.3842 and a coefficient of determination of 0.673 for the full equation with F = 6.52 and P < 0.01. CONCLUSION: Status of environmental health in kindergartens plays an important role in children's lead exposure. It is necessary to offer health education for children and make them wash their hands often and overcome unhealthy behavior of sucking their fingers.
Notes: Chinese
Chung-Hua Yu Fang i Hsueh Tsa Chih [Chinese Journal of Preventive Medicine]. 33(5)
Journal Article

Reference Type: Journal Article
Record Number: 8
Author: Gonzalez, E. J.; Pham, P. G.; Ericson, J. E.; Baker, D. B.
Title: Tijuana childhood lead risk assessment revisited: validating a GIS model with environmental data
Pages: 559-65, 2002 Apr.
Accession Number: 12071505
Abstract: The objective of this research was to determine the spatial distributions of childhood lead poisoning and soil lead contamination in urban Tijuana. The Bocco-Sanchez model of point-source emissions was evaluated in terms of validity and reliability. We compared the model's predicted vulnerable populations with observed cases of childhood lead poisoning in Tijuana, identified fixed point sources in the field, and analyzed 76 soil samples from 14 sites. The soil lead results were compared to the blood lead analyses performed on Tijuana children whose blood lead levels were > or =10 microg/dL, who reported that they did not use lead-glazed ceramics for cooking or storing food (n = 63). Using GIS, predicted vs observed risk areas were assessed by examining spatial patterns, including the distribution of cases per designated risk area. Chi-square analysis of expected vs observed values did not differ significantly at the p = 0.02 level, showing that the model was strikingly accurate in predicting the distribution of subjects with elevated blood lead. Results reveal that while point sources are significant, other sources of lead exposure are also important. The relative public health risk from exposure to lead in an urban setting may be assessed by distinguishing among sources of exposure and associating concentrations to blood lead levels. The results represent an iterative approach in environmental health research by linking environmental and human biomarker lead concentrations and using these results to validate an environmental model of risk to lead exposure.
Notes: Environmental Management. 29(4)
Journal Article
Validation Studies

Title: Sources of lead in soil and dust and the use of dust fallout as a sampling medium
Author:B. L. Gulson, J. J. Davis, K. J. Mizon, M. J. Korsch and J. Bawden-Smith
Abstract: Pilot investigations using stable lead isotope and scanning electron microscopic analyses have been undertaken in different environments ranging from mining and smelting to urban in order to better understand the source of, and relationships between, soil and house dust. House dust is characterised by vacuum cleaner dust and/or surface wipes and compared with long-term dust (dust fall) accumulations over a > 3-month interval or with airborne particulates. Finer grain sizes of soils have lead concentrations from 2 to 9 times those measured in the bulk fractions. In Broken Hill isotopic ratios show that the major source of lead in soils is from the orebody, with rare examples containing lead from paint sources. In inner Sydney, soil lead values vary from 37 to 2660 ppm Pb in bulk samples and up to 3130 ppm in the finer fractions. The lead may be from diverse sources such as gasoline or paint. Finer fractions of vacuum cleaner dust from both Broken Hill and Sydney may contain up to three times the amount of lead measured in the bulk samples. In Broken Hill, the percentages by weight of total lead in the −250-μm fraction range from 11 to 51%. Bulk vacuum cleaner dusts from Broken Hill contain up to 4490 ppm Pb. Bulk vacuum cleaner dusts from inner Sydney contain up to 2950 ppm Pb. Isotopic variations in fractions of vacuum cleaner dust containing > 1000 ppm Pb from inner Sydney indicate that the lead in dust has come from different sources and such differences lessen the usefulness of analyses of bulk vacuum cleaner dust. Our results reinforce the importance of analysing the finer fraction of soil and house dust, especially those in the −150-μm (or even −100-μm) fraction for soils and the −100-μm fraction for vacuum cleaner dust. Dust-fall accumulations have many advantages over more conventional methods for estimating lead in house dust, such as vacuum cleaner dust or surface wipes. These advantages include: low cost; no power source required; can be set up by a technician; minimal inconvenience to householder (i.e., no power required, no noise, out of the way, a few minutes to set up and collect); integrates lead flux over a specific period; usually unbiased (in contrast to vacuuming or wipes where the householder may clean prior to a sampling visit); easy to control by placement of other dishes in the same house. For Broken Hill, a strong correlation (r = 0.95) was obtained between the isotopic composition of lead in blood and dust-fall accumulation.
Abstract: Science of The Total Environment Volume 166, Issues 1-3 , 21 April 1995, Pages 245-262

Author:Harris AR, Davidson CI.2005. The role of resuspended soil in lead flows in the California South Coast Air Basin. Environ Sci Technol. 2005 Oct 1;39(19):7410-5.
Abstract: The inputs and outputs of airborne lead in the South Coast Air Basin of California (SOCAB) are quantified according to standard mass balance calculations. Results for 2001 show that approximately 49,000 kg of lead exitthe Basin each year, but traditional sources contribute only about 6500 kg of lead each year. We resolve this discrepancy through a simple computer model that quantifies the resuspension of lead-containing particles. Our results suggest that these lead particles were deposited during the years of leaded gasoline use and that resuspension is responsible for generating an additional 54,000 kg of airborne lead each year. This agrees roughly with estimated outputs. Thus, we conclude that resuspension, although an insignificant source of airborne lead during the era of leaded fuel, became a principal source in the SOCAB as lead emissions from vehicles declined. The results of the resuspension model further suggest that soil lead levels will remain elevated for many decades, in which case resuspension will remain a major source well into the future.

Reference Type: Journal Article
Record Number: 64
Author: Hertzman, C.; Ward, H.; Ames, N.; Kelly, S.; Yates, C.
Title: Childhood lead exposure in Trail revisited
Pages: 385-91, 1991 Nov-Dec.
Accession Number: 1790501
Abstract: We sought to identify modifiable determinants of elevated blood lead levels in preschool children; to compare the current situation with past information; to determine historical trends in environmental lead contamination in Trail; and to find a basis for identifying appropriate precautions and protection against future lead exposure. In Phase 1, blood samples were drawn from all children aged 2 to 5. In Phase 2, children in the highest and lowest quartile of blood leads were surveyed by questionnaire. Environmental samples of drinking water, paint, housedust, soil and vegetables were taken from their residences, and soil samples were collected from nearby parks. The average blood lead level was 13.8 micrograms/dl, range 4 to 30 micrograms/dl. This is approximately 40% lower than in 1975, when a previous survey was done, but is high compared to other places in Canada. The study of environmental determinants of lead revealed that soil lead levels and, secondarily, housedust lead levels are the principal determinants of high blood lead. Children with high blood leads also tended to concentrate in neighbourhoods near the lead-zinc smelter.
Notes: Canadian Journal of Public Health. Revue Canadienne de Sante Publique. 82(6)
Journal Article

b>Reference Type: Journal Article
Author: Janneke Hogervorst, Michelle Plusquin, Jaco Vangronsveld, Tim Nawrot, Ann Cuypers, Etienne Van Heck, Harry A. Roels, Robert Carleer and Jan A. StaessenBR> Title:House dust as possible route of environmental exposure to cadmium and lead in the adult general population
Abstract: Contaminated soil particles and food are established routes of exposure. We investigated the relations between biomarkers of exposure to cadmium and lead, and the metal loading rates in house dust in the adult residents of an area with a soil cadmium concentration of 3 mg/kg (n=268) and a reference area (n=205). We determined the metal concentrations in house dust allowed to settle for 3 months in Petri dishes placed in the participants bedrooms. The continuously distributed vegetable index was the first principal component derived from the metal concentrations in six different vegetables. The biomarkers of exposure (blood cadmium 9.2 vs. 6.2 nmol/L; 24-h urinary cadmium 10.5 vs. 7.0 nmol; blood lead 0.31 vs. 0.24 μmol/L), the loading rates of cadmium and lead in house dust (0.29 vs. 0.12 and 7.52 vs. 3.62 ng/cm2/92 days), and the vegetable indexes (0.31 vs. −0.44 and 0.13 vs. −0.29 standardized units) were significantly higher in the contaminated area. A two-fold increase in the metal loading rate in house dust was associated with increases (P<0.001) in blood cadmium (+2.3%), 24-h urinary cadmium (+3.0%), and blood lead (+2.0%), independent of the vegetable index and other covariates. The estimated effect sizes on the biomarkers of internal exposure were three times greater for house dust than vegetables. In conclusion, in the adult population, house dust is potentially an important route of exposure to heavy metals in areas with contaminated soils, and should be incorporated in the assessment of health risks.
Notes: Environ Res. 2006 Jul 12

Title:Mass transfer of soil indoors by track-in on footwear
Author: Andrew Hunt,David L. Johnsonb and Daniel A. Griffith
Abstract:nadvertent soil ingestion, especially by young children, can be an important route of exposure for many environmental contaminants. The introduction of exterior soil into the interior environment is a significant element of the exposure pathway. The unintentional collection of outside soil on footwear followed by subsequent deposition indoors is a principal route of soil ingress. Here we have investigated likely rates of dry and wet soil deposition on indoor hard surface flooring as a result of mass transfer from soiled footwear. In this pilot study, testing involved both single track-in events (with deposition resulting from a single progression of transfer steps) and multiple tracking actions (with deposition and dispersion resulting from repeated transfer steps). Based on soil mass recovery from the floor surface it was found that any contamination introduced by one-time track-in events was of limited spatial extent. In contrast, under repeated tracking conditions, with multiple soil incursions, widespread floor surface contamination was possible. Soil mass recovery was accomplished by brushing, by vacuum cleaner removal and by wet wiping. All the clean-up methods operated imperfectly and failed to remove all initially deposited soil. The level of floor surface soiling that resulted from the track-in tests, and the incomplete clean-up strongly suggest that under unrestricted transfer conditions rapid accumulation and dispersal of soil on indoor flooring is likely.
Notes: Science of the Total Environment. doi:10.1016/j.scitotenv.2006.07.013

Reference Type: Journal Article
Record Number: 16
Author: Hynes, H. P.; Maxfield, R.; Carroll, P.; Hillger, R.
Title: Dorchester Lead-Safe Yard project: a pilot program to demonstrate low-cost, on-site techniques to reduce exposure to lead-contaminated soil
Pages: 199-211, 2001 Mar.
Accession Number: 11368198
Abstract: Despite a general reduction in blood lead levels in children after lead was banned in gasoline and paint, lead poisoning remains an important health problem in many older urban areas. One factor that increases risk in these places is the high levels of lead in certain residential areas. A major intervention study found that reducing lead levels in urban soils results in a reduction in exposed children's blood lead levels. Removing lead from inner-city soils or reducing exposures to lead-contaminated soils typically is expensive, technologically challenging, or beyond the ability of low-income households to undertake. This project, in conjunction with residents and community-based institutions, developed a series of in situ, low-cost, low-technology measures that worked to reduce the exposure to lead-contaminated soils in one Boston, Massachusetts, neighborhood. The project demonstrated several important results. Government, universities, residents, and community based organizations can work together effectively to reduce exposures to lead in soil. Lead-contaminated soil can be mitigated at a fraction of the cost of conventional methods in ways that increase the ability of residents, community health centers, and others to have a positive impact on their neighborhoods. A lead-safe yard program can be replicated and institutionalized by municipal home de-leading programs and other community organizations.
Notes: Journal of Urban Health. 78(1)
Journal Article

Reference Type: Journal Article
Record Number: 48
Author: Jacobsen, P.
Title: [Exposure of children to lead from contaminated soil]
Pages: 1499-502, 1996 Mar 11.
Accession Number: 8644394
Abstract: To assess lead exposure in infants from contaminated soil a review of epidemiological studies was performed. Seventeen studies fulfilled criteria of individual exposure measures and a relevant confounder control. In 10 of these a clear association between blood lead and lead in soil was demonstrated after control of confounders. With some reservations three additional studies indicated an effect. No effect on blood lead from soil exposure was found in four studies. Quantitative estimates of the contributions to blood lead from soil varied within a wide range. In the best designed study-a controlled intervention against contaminated soil-blood lead values declined a little more than 1 microgram/100 ml per 1000 ppm. reduction of soil lead concentration. Oral exposure, probably by mouthing behaviour, was indicated by modification of the association between blood and soil lead from time spent outdoors, area with uncovered soil, age and mouthing behaviour in several studies. The conclusions from the review were that children's mouthing behaviour on lead contaminated soil may affect blood lead, but the contribution to overall lead exposure seems to be relatively small. Considering the limited margin of safety for lead exposure an intervention regimen for contaminated areas where infants have direct and continued contact with soil is suggested. Intervention in other places is unlikely to significantly reduce the lead burden of children. Simultaneously with intervention a programme for the evaluation of its effect is proposed. [References: 22]
Notes: Review
Ugeskrift for Laeger. 158(11)
Journal Article
Review, Tutorial

Reference Type: Journal Article
Record Number: 38
Author: Jin, A.; Teschke, K.; Copes, R.
Title: The relationship of lead in soil to lead in blood and implications for standard setting
Pages: 23-40, 1997 Dec 3.
Accession Number: 9496646
Abstract: As part of a soil lead regulation process, this review was conducted to determine the association between lead in soil and established human health effects of lead or validated biomarkers of lead exposure. We reviewed only studies where soil exposure could be distinguished from other sources of lead and whose design could reasonably be used to infer a causal relationship between soil lead and either biomarkers or health effects. No such studies of health effects were found. Studies describing a quantitative relationship between soil lead and blood lead did meet our criteria: 22 cross-sectional studies in areas with polluted soil; and three prospective studies of soil lead pollution abatement trials. The cross-sectional studies indicated that, compared to children exposed to soil lead levels of 100 ppm, those exposed to levels of 1000 ppm had mean blood lead concentrations 1.10-1.86 times higher and those exposed to soil lead levels of 2000 ppm had blood lead concentrations 1.13-2.25 times higher. The prospective studies showed effects within the ranges predicted by the cross-sectional studies. Differences in results between studies were surprisingly modest and likely explainable by random sampling error, different explanatory variables included in data analyses and differences in methods of measuring lead in environmental specimens.
Notes: Science of the Total Environment. 208(1-2)
Journal Article

Author:Johnson D, Bretsch J. 2002. Soil lead and children's BLL Levels in Syracuse, NY, USA. Environ Geochem Health 24(4):375-385.
Abstract: A geo-referenced data set of 12 228 first-time blood lead screening values for Syracuse, NY, children was established for the 4-year period 1992-1996. Soil lead values were measured in a 600 m by 600 m tessellation grid covering the city. The two data sets were merged for evaluation of relationships between them. Strong seasonal variation in blood lead levels suggests the importance of contaminated soils as an exposure source. When the data were aggregated at a large geographic scale (3 km2), a logarithmic model showed an R2 of > 0.65 for the regression of geometric mean blood lead on median soil lead values. Results showed a striking similarity to those obtained by Mielke et al. (1999) for a study in New Orleans, LA, USA.

Author:George D. Kamenov
Title:High-precision Pb isotopic measurements of teeth and environmental samples from Sofia (Bulgaria): insights for regional lead sources and possible pathways to the human body
Notes:Environmental Geology. Volume 55, Number 3 / August, 2008. DOI 10.1007/s00254-007-1017-y. p. 669-680
Abstract:High-precision Pb isotopic measurements on teeth and possible sources in a given area can provide important insights for the lead (Pb) sources and pathways in the human body. Pb isotopic analyses on soils from the area of Sofia, Bulgaria show that Pb is contributed by three end-members represented by two natural sources and leaded gasoline. Sequential leaching experiments reveal that the alumosilicate fraction of the soils is mainly controlled by natural Pb derived from two mountain massifs bordering the city. Around 1/3 to a half of the Pb in the soil leachates, however, can be explained by contamination from leaded gasoline. Contemporary teeth from Sofia residents show very similar Pb isotopic compositions to the soil leachates, also indicating that around 1/3 to a half of the Pb can be explained by derivation from leaded gasoline. The remarkable isotopic similarities between the teeth and the most labile fractions of the local soils suggest that the lead can be derived from the latter. Pb incorporation in the human body via soil-plant human or soil plant animal human chains is unlikely due to the fact that no significant farming occurs in the city area. The isotopic compositions of the local soil labile fractions can be used as approximation of the bioaccessible lead for humans. Considering all possible scenarios it appears that soil and/or soil-born dust inhalation and/or ingestion is the most probable pathway for incorporation of local soil lead in the local population. The high-precision Pb isotope data presented in this work indicate that apparently the local soil is what plays major role in the human Pb exposure.

Author:Kurkjian R, Flegal AR. 2003. Isotopic evidence of the persistent dominance of blood lead concentrations by previous gasoline lead emissions in Yerevan, Armenia. Environ Res 93(3):308-315.
Abstract:Recent (1999) blood lead (PbB) isotopic compositions (n=17) of males and females in Yerevan, Armenia, indicate that previous emissions of leaded gasoline still dominate the populace's PbB concentrations 2 years after the country's apparent de facto elimination of leaded gasoline in Armenia. The range of PbB isotopic compositions overlaps those of air and near-road surface soils in Yerevan, and the averages of those isotopic compositions in blood (208Pb/207Pb=2.442; 206Pb/207Pb=1.158) and near-road soils (208Pb/207Pb=2.442; 206Pb/207Pb=1.157) are indistinguishable. Using a proxy for historic leaded-gasoline emissions in Armenia, these analyses suggest that leaded gasoline was, is, and will continue to be via the resuspension of lead-bound soils contaminated by previous depositions from leaded-gasoline emissions, a relatively important source of industrial lead in both Yerevan's atmosphere and its populace. However, the level of lead contamination in the Armenian populace, based on the PbB geometric mean of 4.0 ug/dL (n=49) measured in this initial survey, appears to be much lower than recently proposed by the Armenian Ministry of Nature Protection.

Author:D A V I D W . L A Y T O N A N D P A L O M A I . B E A M E R * 2009. Migration of Contaminated Soil and Airborne Particulates to Indoor Dust Environ. Sci. Technol. 2009, 43, 8199-8205
Abstract: We have developed a modeling and measurement framework for assessing transport of contaminated soils and airborne particulates intoaresidence, their subsequent distribution indoors via resuspension and deposition processes, and removal by cleaning and building exhalation of suspended particles. The model explicitly accounts for the formation of house dust as a mixture of organic matter (OM) such as shed skin cells and organic fibers, soil tracked-in on footwear, and particulate matter (PM) derived from the infiltration of outdoor air. We derived formulas for use with measurements of inorganic contaminants, crustal tracers, OM, and PM to quantify selected transport parameters. Application of the model to residences in the U.S. Midwest indicates that As in ambient air can account for nearly 60% of the As input to floor dust, with soil track-in representing the remainder. Historic data on Pb contamination in Sacramento, CA, were used to reconstruct sources of Pb in indoor dust, showing that airborne Pb was likely the dominant source in the early 1980s. However, as airborne Pb levels declineddueto the phase-out ofleadedgasoline, soil resuspension and track-in eventually became the primary sources of Pb in house dust.

Reference Type: Journal Article
Record Number: 89
Author:Laidlaw, M.A., Zahran, S., Mielke, H.W., Taylor, M.P., Filippelli, G.M.
ReferenceLaidlaw, M.A., Zahran, S., Mielke, H.W., Taylor, M.P., Filippelli, G.M., Re-suspension of lead contaminated urban soil as a dominant source of atmospheric lead in Birmingham, Chicago, Detroit and Pittsburgh, USA, Atmospheric Environment (2011), doi: 10.1016/ j.atmosenv.2011.11.030
AbstractSoils in older areas of cities are highly contaminated by lead, due largely to past use of lead additives in gasoline, the use of lead in exterior paints, and industrial lead sources. Soils are not passive repositories and periodic re-suspension of fine lead contaminated soil dust particulates (or aerosols) may create seasonal variations of lead exposure for urban dwellers. Atmospheric soil and lead aerosol data from the Interagency Monitoring of Protected Visual Environments (IMPROVE) database were obtained for Pittsburgh (Pennsylvania), Detroit (Michigan), Chicago (Illinois), and Birmingham (Alabama), USA. In this study the temporal variations of atmospheric soil and lead aerosols in these four US cities were examined to determine whether re-suspended lead contaminated urban soil was the dominant source of atmospheric lead. Soil and lead-in-air concentrations were examined to ascertain whether lead aerosols follow seasonal patterns with highest concentrations during the summer and/or autumn. In addition, atmospheric soil and lead aerosol concentrations on weekends and Federal Government holidays were compared to weekdays to evaluate the possibility that automotive turbulence results in re-suspension of lead contaminated urban soil. The results show that the natural logs of atmospheric soil and lead aerosols were associated in Pittsburgh from April 2004 to July 2005 (R2 = 0.31, p < 0.001), Detroit from November 2003 to July 2005 (R2 = 0.49, p = < 0.001), Chicago from November 2003 to August 2005 (R2 = 0.33, p = < 0.001), and Birmingham from May 2004 to December 2006 (R2 = 0.47, p <0.001). Atmospheric soil and lead aerosols followed seasonal patterns with highest concentrations during the summer and/or autumn. Atmospheric soil and lead aerosols are 3.15 and 3.12 times higher, respectively, during weekdays than weekends and Federal Government holidays, suggesting that automotive traffic turbulence plays a significant role in re-suspension of contaminated roadside soils and dusts. In order to decrease urban lead aerosol concentrations, lead deposition and subsequent children’s seasonal exposure, lead contaminated urban soils need remediation or isolation because the legacy of lead continues to pose unnecessary and preventable health risks to urban dwellers.

Reference Type: Journal Article
Record Number: 89
Author:Laidlaw M.A.S. and Taylor P.
Title: Potential for childhood lead poisoning in the inner cities of Australia due to exposure to lead in soil dust
Abstract This article presents evidence demonstrating that the historical use of leaded gasoline and lead (Pb) in exterior paints in Australia has contaminated urban soils in the older inner suburbs of large cities such as Sydney and Melbourne. While significant attention has been focused on Pb poisoning in mining and smelting towns in Australia, relatively little research has focused on exposure to Pb originating from inner-city soil dust and its potential for childhood Pb exposures. Due to a lack of systematic blood lead (PbB) screening and geochemical soil Pb mapping in the inner cities of Australia, the risks from environmental Pb exposure remain unconstrained within urban population centres.
Journal: Environmental Pollution

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Reference Type: Journal Article
Record Number: 89
Author: Laidlaw, M. A.; Mielke, H. W.; Filippelli, G. M.; Johnson, D. L.; Gonzales, C. R.
Title:Seasonality and children's blood lead levels: developing a predictive model using climatic variables and blood lead data from Indianapolis, Indiana, Syracuse, New York, and New Orleans, Louisiana (USA)
Pages: 793-800, 2005 Jun.
Accession Number: 15929906
Abstract: On a community basis, urban soil contains a potentially large reservoir of accumulated lead. This study was undertaken to explore the temporal relationship between pediatric blood lead (BPb), weather, soil moisture, and dust in Indianapolis, Indiana; Syracuse, New York; and New Orleans, Louisiana. The Indianapolis, Syracuse, and New Orleans pediatric BPb data were obtained from databases of 15,969, 14,467, and 2,295 screenings, respectively, collected between December 1999 and November 2002, January 1994 and March 1998, and January 1998 and May 2003, respectively. These average monthly child BPb levels were regressed against several independent variables: average monthly soil moisture, particulate matter < 10 microm in diameter (PM10), wind speed, and temperature. Of temporal variation in urban children's BPb, 87% in Indianapolis (R2 = 0.87, p = 0.0004), 61% in Syracuse (R2 = 0.61, p = 0.0012), and 59% in New Orleans (R2 = 0.59, p = 0.0000078) are explained by these variables. A conceptual model of urban Pb poisoning is suggested: When temperature is high and evapotranspiration maximized, soil moisture decreases and soil dust is deposited. Under these combined weather conditions, Pb-enriched PM10 dust disperses in the urban environment and causes elevated Pb dust loading. Thus, seasonal variation of children's Pb exposure is probably caused by inhalation and ingestion of Pb brought about by the effect of weather on soils and the resulting fluctuation in Pb loading.
Notes: Environmental Health Perspectives. 113(6)

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Author: Laidlaw, M. A. S. ; Filippelli, G. M.
Title:Reducing The Lead-Load For Urban Youth: The Role Of Atmospheric Soil Re-suspension as a Significant Public Health Threat In The United States
Abstract: Children's lead poisoning in urban areas in the United States follows a seasonal pattern with a peak in the summer months. We recently found that that weather and soil moisture variables robustly predicted seasonal changes in children's blood lead levels in a number of US cities. We concluded that the weather and soil moisture variables were a proxy of seasonal soil re-suspension and exposure of children to lead contaminated urban soils, with the potential to use site-specific weather and soil moisture determinations to better assess clinical blood Pb data. In order to test the hypothesis that atmospheric soil concentrations display a seasonal pattern, time series of atmospheric soil concentrations were obtained at eight IMPROVE locations across the United States. Results indicate that continental atmospheric soil concentrations exhibit strong seasonality and increase up to an order of magnitude between winter (minimum) and summer (maximum). In order to test the hypothesis that atmospheric soil seasonality is related to weather and soil moisture variables, atmospheric soil concentrations at the Bondville, Illinois IMPROVE site were regressed against the independent variables minimum relative humidity, field measured soil moisture, precipitation, temperature, wind speed, atmospheric pressure, while adjusting for the month of the year. The model time period was 37 months. Results indicate that eighty-three percent of the temporal variation of atmospheric soil concentrations (R2=0.83, p = <0.001, DW = 2.06), could be explained by these variables. Our empirical model indicates that when temperatures are high, relative humidity is low, and evapotranspiration maximized, soil moisture decreases, and soil dust is re-suspended into the atmosphere. Correlation of local atmospheric soil concentrations with local soil moisture and atmospheric data suggests that a significant proportion of the atmospheric soil is derived from local sources. The findings that weather and soil moisture variables predict atmospheric soil seasonality (this study) and children's blood lead levels (our previous work) support the hypothesis that seasonal re-suspension of local lead contaminated soils in urban environments is driving seasonal lead poisoning.
Notes:Geological Society of America Annual Meeting (Philadelphia; 22�25 October 2006.)

Author: Laidlaw, M. A. S. ; Filippelli, G. M.
Title:Resuspension of urban soils as a persistent source of lead poisoning in children: A review and new directions
Abstract: Urban soils act as the repository for a number of environmental burdens, including Pb. Significant attention has been devoted to reducing Pb burdens to children with outstanding success, but the fact that blood Pb levels above 10 μg/dL are disproportionately found in children living in many U.S.A. cities (15-20% in some cities compared to a national average of less than 2%) indicates that not all of the sources have been eliminated. Although the health risk of fine particulates has begun to raise concerns in cities, little attention has been paid to Pb associated with these particulates and the potential role of this pathway for continued Pb burdens of urban youth. This review summarizes recent work on particulate resuspension and the role of resuspension of Pb-enriched urban soils as a continued source of bioavailable Pb both outside and inside homes, then presents recent efforts to model Pb burdens to children based on the atmospheric parameters that drive particulate resuspensiconc