Lead Laboratory Inc.

New Orleans, LA, United States

Lead Laboratory Inc.

New Orleans, LA, United States
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Zahran S.,Colorado State University | Mielke H.W.,Tulane University | Gonzales C.R.,Lead Laboratory Inc. | Powell E.T.,Lead Laboratory Inc. | Weiler S.,Colorado State University
Environmental Science and Technology | Year: 2010

Prior to Hurricanes Katrina and Rita (HKR), significant associations were noted between soil lead (SL) and blood lead (BL) in New Orleans. Engineering failure of New Orleans levees and canal walls after HKR set the stage for a quasi-experiment to evaluate BL responses by 13-306 children to reductions in SL. High density soil surveying conducted in 46 census tracts before HKR was repeated after the flood. Paired t test results show that SL decreased from 328.54 to 203.33 mg/kg post-HKR (t = 3.296, p ≤ 0.01). Decreases in SL are associated with declines in childrens BL response (r = 0.308, p ≤ 0.05). When SL decreased at least 1%, median childrens BL declined 1.55 μg/dL. Declines in median BL are largest in census tracts with≥50% decrease in SL. Also individual BL in children was predicted as a function of SL, adjusting for age, year of observation, and depth of flood waters. At the individual scale, BL decreased significantly in post-HKR as a function of SL, with BL decreases ranging from b = -1.20 to -1.65 μg/dL, depending on the decline of SL and whether children were born in the post-HKR period. Our results support policy to improve soil conditions for children. © 2010 American Chemical Society.

Mielke H.W.,Center for Bioenvironmental Research at Tulane and Xavier Universities | Mielke H.W.,Tulane University | Gonzales C.R.,Xavier University of Louisiana | Cahn E.,Pitzer College | And 3 more authors.
Environmental Geochemistry and Health | Year: 2010

Arsenic (As) ranks first on the 2005 and 2007 hazardous substances priority lists compiled for the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). This study describes two New Orleans soil As surveys: (1) a survey of composite soil samples from 286 census tracts and (2) a field survey of soil As at 38 play areas associated with the presence of chromated-copper-arsenate (CCA)-treated wood on residential and public properties. The survey of metropolitan New Orleans soils revealed a median As content of 1.5 mg/kg (range <0.2-16.4) and no distinctive differences between the soils of the city core and outlying areas. Play area accessible soils associated with CCA-treated wood (N = 32) had a median As of 57 mg/kg and 78% of the samples were ≥12 mg/kg, the Louisiana soil As standard. The field survey of play areas for CCA-treated wood (N = 132 samples at 38 sites) was conducted with a portable energy-dispersive X-ray fluorescence (XRF) analyzer. Seventy-five of 132 wood samples (56.8%) were deemed CCA-treated wood. Of the 38 play areas surveyed, 14 (36.8%) had CCA-treated wood. A significant association (Fisher's exact p-value = 0.348 × 10 -6) was found between CCA-treated wood and soil As (N = 75). At one elementary school CCA-treated woodchips (As range 813-1,654 mg As/kg) covered the playgrounds. The situation in New Orleans probably exists in play areas across the nation. These findings support a precautionary program for testing soils and wood for hazardous substances at all play areas intended for children. © 2010 Springer Science+Business Media B.V.

Mielke H.W.,Tulane University | Mielke H.W.,Xavier Universities | Covington T.P.,Delgado Community College | Covington T.P.,University of South Alabama | And 4 more authors.
Environmental Pollution | Year: 2011

The feasibility of reducing children's exposure to lead (Pb) polluted soil in New Orleans is tested. Childcare centers (median = 48 children) are often located in former residences. The extent of soil Pb was determined by selecting centers in both the core and outlying areas. The initial 558 mg/kg median soil Pb (range 14-3692 mg/kg) decreased to median 4.1 mg/kg (range 2.2-26.1 mg/kg) after intervention with geotextile covered by 15 cm of river alluvium. Pb loading decreased from a median of 4887 μg/m2 (454 μg/ft 2) range 603-56650 μg/m2 (56-5263 μg/ft2) to a median of 398 μg/m2 (37 μg/ft2) range 86-980 μg/m2 (8-91 μg/ft2). Multi-Response Permutation Procedures indicate similar (P-values = 0.160-0.231) soil Pb at childcare centers compared to soil Pb of nearby residential communities. At ∼$100 per child, soil Pb and surface loading were reduced within hours, advancing an upstream intervention conceptualization about Pb exposure prevention. © 2010 Elsevier Ltd. All rights reserved.

Zahran S.,Colorado State University | Mielke H.W.,Tulane University | Weiler S.,Colorado State University | Hempel L.,Colorado State University | And 2 more authors.
Environmental Pollution | Year: 2012

In New Orleans a strong inverse association was previously identified between community soil lead and 4th grade school performance. This study extends the association to zinc, cadmium, nickel, manganese, copper, chromium, cobalt, and vanadium in community soil and their comparative effects on 4th grade school performance. Adjusting for poverty, food security, racial composition, and teacher-student ratios, regression results show that soil metals variously reduce and compress student scores. Soil metals account for 22%-24% while food insecurity accounts for 29%-37% of variation in school performance. The impact on grade point averages were Ni > Co > Mn > Cu ∼Cr ∼ Cd > Zn > Pb, but metals are mixtures in soils. The quantities of soil metal mixtures vary widely across the city with the largest totals in the inner city and smallest totals in the outer city. School grade point averages are lowest where the soil metal mixtures and food insecurity are highest. © 2012 Elsevier Ltd. All rights reserved.

Mielke H.W.,Tulane University | Gonzales C.R.,Lead Laboratory Inc. | Mielke P.W.,Colorado State University
Environmental Research | Year: 2011

Background: Compared with a maximum collective lead (Pb) estimate of ~1811 metric tons (MT) in exterior paint on 86,000 New Orleans houses, Pb additives in gasoline were estimated at ~12,000. MT in New Orleans, yielding ~9100. MT Pb exhausted as aerosols from vehicles; ~4850. MT were particles >10. μm and ~4200. MT were particles <0.25. μm. Objectives: To evaluate pre-Hurricane Katrina soil Pb and children's blood Pb at public housing and private residential properties in the inner-city compared with the outer city of New Orleans. Methods: This study includes 224 soil samples from 10 public housing properties and 363 soil samples from residential private properties within an 800 m radius of centroids of public housing census tracts. The Louisiana Childhood Lead Poisoning Prevention Program data from 2000 to 2005 (pre-Hurricane Katrina) was the source for 9807 children's blood Pb (μg/dL) results. Soil and blood Pb data were grouped by public housing census tracts and private residential properties. This study uses Multi-Response Permutation Procedures for statistical analysis. Results: Brick public properties in the city core had significantly more soil Pb contamination and higher prevalence of elevated children's blood Pb than same-aged brick public properties in the outer areas of the city. The pre-Hurricane Katrina New Orleans concentration of Pb dust in the inner-city soil displayed a median of 438mg/kg or 3.7 times larger than Pb dust in outlying areas where the median soil Pb was 117mg/kg (p-value=2.9×10 -15). Also, the pre-Hurricane Katrina prevalence of children's blood Pb ≥10μg/dL was 22.9% within the inner-city compared with 9.1% in the outer areas of New Orleans (p-value=3.4×10 -74). Conclusions: Comparing the quantities of Pb dust from paint and Pb additives to gasoline, this study supports the later source as a more plausible explanation for the differences in soil Pb and children's blood Pb within public and private housing in the higher traffic congested inner-city core compared with the lower traffic congested outer areas of New Orleans. Similar patterns of environmental Pb dust contamination and childhood Pb exposure are expected in all cities. © 2011 Elsevier Inc.

Zahran S.,Colorado State University | Mielke H.W.,Tulane University | Weiler S.,Colorado State University | Gonzales C.R.,Lead Laboratory Inc
Science of the Total Environment | Year: 2011

Previous studies identified a curvilinear association between aggregated blood lead (BL) and soil lead (SL) data in New Orleans census tracts. In this study we investigate the relationships between SL (mg/kg), age of child, and BL (μg/dL) of 55,551 children in 280 census tracts in metropolitan New Orleans, 2000 to 2005. Analyses include random effects regression models predicting BL levels of children (μg/dL) and random effects logistic regression models predicting the odds of BL in children exceeding 15, 10, 7, 5, and 3μg/dL as a function of age and SL exposure. Economic benefits of SL reduction scenarios are estimated. A unit raise in median SL 0.5 significantly increases the BL level in children (b=0.214 p=<0.01), and a unit change in Age 0.5 significantly increases child BL (b=0.401, p=<0.01). A unit change in Age 0.5 increases the odds of a child BL exceeding 10μg/dL by a multiplicative factor of 1.23 (95% CI 1.21 to 1.25), and a unit (mg/kg) addition of SL increases the odds of child BL>10μg/dL by a factor of 1.13 (95% CI 1.12 to 1.14). Extrapolating from regression results, we find that a shift in SL regulatory standard from 400 to 100mg/kg provides each child with an economic benefit ranging from $4710 to $12,624 ($US 2000). Children's BL is a curvilinear function of both age and level of exposure to neighborhood SL. Therefore, a change in SL regulatory standard from 400 to 100mg/kg provides children with substantial economic benefit. © 2010.

Mielke H.W.,Tulane University | Laidlaw M.A.S.,Macquarie University | Gonzales C.R.,Lead Laboratory Inc.
Environment International | Year: 2011

The subject of this paper is lead (Pb) additives in gasoline and their material and health impact from Pb dust inputs into 90 US urbanized areas (UAs). The mass of Pb additives for 90 UAs as a total of the US Pb additives in 1982 were estimated from vehicle travel, vehicle fuel economy (miles/gallon), ratio of leaded to unleaded fuel, and Pb/gallon. About 500billion (10 9) miles of travel in 90 UA's during 1982 account for ~18,000metric tons (MT), or nearly 30% of the US Pb additives in 1982. Applying the 1982 proportions to the 90 UAs for 1950 through 1982 fuel sales by state accounts for ~1.4million MT Pb of the US national total of 4.6million MT during the same years. Fates of Pb additives in engine systems were used to calculate Pb aerosol inputs into the 90 UAs. The inputs range from 100's to more than 100,000MT of Pb depending on a given UA's traffic flow patterns. Soils are the reservoir of urban Pb dust. The median background soil Pb for the US is 16.5mg/kg (range 10.3 to 30.1mg/kg), and less by an order of magnitude or more than soil Pb within larger UAs. Recognizing the US input of massive gasoline Pb additives into UAs assists with comprehending soil Pb differences between large and small UAs, inner and outer areas of UAs, health disparities, and school achievement issues within UAs. The findings underscore the need for controlling accumulated exterior urban Pb dust from gasoline additives along with paint sources that have accumulated in soil to meet the goal of primary childhood Pb exposure prevention. © 2010.

Mielke H.W.,Tulane University | Gonzales C.R.,Lead Laboratory Inc. | Powell E.T.,Lead Laboratory Inc. | Mielke P.W.,Colorado State University
Environment International | Year: 2013

Urban environments are the major sites for human habitation and this study evaluates soil lead (Pb) and blood Pb at the community scale of a U.S. city. There is no safe level of Pb exposure for humans and novel primary Pb prevention strategies are requisite to mitigate children's Pb exposure and health disparities observed in major cities. We produced a rich source of environmental and Pb exposure data for metropolitan New Orleans by combining a large soil Pb database (n=5467) with blood Pb databases (n=55,551 pre-Katrina and 7384 post-Katrina) from the Louisiana Childhood Lead Poisoning Prevention Program (LACLPPP). Reanalysis of pre- and post-Hurricane Katrina soil samples indicates relatively unchanged soil Pb. The objective was to evaluate the New Orleans soil Pb and blood Pb database for basic information about conditions that may merit innovative ways to pursue primary Pb exposure prevention. The city was divided into high (median census tract soil≥100mg/kg) and low Pb areas (median census tract soil<100mg/kg). Soil and blood Pb concentrations within the high and low Pb areas of New Orleans were analyzed by permutation statistical methods. The high Pb areas are toward the interior of the city where median soil Pb was 367, 313, 1228, and 103mg/kg, respectively for samples collected at busy streets, residential streets, house sides, and open space locations; the low Pb areas are in outlying neighborhoods of the city where median soil Pb was 64, 46, 32, and 28mg/kg, respectively for busy streets, residential streets, house sides, and open spaces (P-values<10-16). Pre-Katrina children's blood Pb prevalence of ≥5μg/dL was 58.5% and 24.8% for the high and low Pb areas, respectively compared to post-Katrina prevalence of 29.6% and 7.5%, for high and low Pb areas, respectively. Elevated soil Pb permeates interior areas of the city and children living there generally lack Pb safe areas for outdoor play. Soil Pb medians in outlying areas were safer by factors ranging from 3 to 38 depending on specific location. Patterns of Pb deposition from many decades of accumulation have not been transformed by hastily conducted renovations during the seven year interval since Hurricane Katrina. Low Pb soils available outside of cities can remedy soil Pb contamination within city interiors. Mapping soil Pb provides an overview of deposition characteristics and assists with planning and conducting primary Pb exposure prevention. © 2012 Elsevier Ltd.

Mielke H.W.,Tulane University | Gonzales C.,Lead Laboratory Inc | Powell E.,Lead Laboratory Inc | Mielke P.W.,Colorado State University
International Journal of Environmental Research and Public Health | Year: 2014

In 2012 the U.S. Centers for Disease Control (CDC) set the blood Pb reference value at ≥5 μg/dL. Clinical analysis of children's blood Pb levels is the common way to diagnose environmental Pb contamination, and intervention ensues with education and household dust cleanup. Recent review indicates that education and household dust cleanup are not effective at reducing children's Pb exposure. Here we review mapping environmental Pb and children's blood Pb response as an alternative approach for proactive Pb dust intervention. New Orleans was divided into a high (≥100 mg/kg) and low (<100 mg/kg) soil Pb communities. The children's blood Pb prevalence ≥5 μg/dL for the high and low Pb domains were 58.5% and 24.8% respectively pre-Katrina vs. 29.6% and 7.5% post-Katrina. Elevated soil Pb (mg/kg) and consequently Pb loading (μg/square area) permeates the high Pb domain and outdoor locations lack Pb dust safe play areas. The U.S. EPA 400 mg/kg soil Pb standard poses an outside Pb dust loading burden >37 times larger than allowed on interior residential floor environments. Environmental Pb dust is decreasing because of the transfer of large quantities of low Pb soil into selected communities. City-scale soil Pb mapping is an alternative diagnostic tool that provides information for planning proactive medicine to prevent clinical Pb exposure in the first place. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

Mielke H.W.,Tulane University | Laidlaw M.A.S.,Macquarie University | Gonzales C.,Lead Laboratory Inc.
Science of the Total Environment | Year: 2010

This article describes the magnitude of U.S. lead (Pb) additives in gasoline from 1927 to 1994 and estimated quantities of Pb dispersed by vehicle traffic in eight urbanized areas (UAs) of California from 1950 to 1982. The findings are the basis for predicting the health impact of Pb on children living in UA of California. Quantitative U.S. national data for 1927-1994 were from the U.S. Senate hearing of the 1984 Airborne Lead Reduction Act. Vehicle traffic data, fuel efficiency, percentage leaded gasoline, and quantities of Pb in gasoline were obtained for 1982 from public and corporate records to estimate vehicle Pb emissions for small to very large UAs of California. California fuel consumption records and yearly quantities of Pb additives per gallon were the basis for estimating the 1950-1982 dispersion of Pb in each UA. Lead additives were calculated by multiplying annual vehicle fuel used by average Pb per gallon. The proportion of Pb additive for each UA was calculated from vehicle miles traveled (VMT) driven in 1982 divided by miles per gallon fuel consumption times the ratio of leaded to unleaded fuel times Pb additive per gallon. U.S. Environmental Protection Agency calculations of the fates of Pb were used to estimate Pb aerosol dispersal in each UA. About 108 billion miles of travel in 1982 within 8 UAs accounts for 3200. metric tons of Pb additives or ~60% total Pb additives in California. Between the 1950-1982 peak of Pb additives, about 258,000. metric tons are accounted for out of the state 412,000. metric tons total during the same time period. The estimates of the quantities of Pb dust that accumulated within various UAs in California assists with predicting the continuing influences of Pb on children's exposure. Mapping the soil Pb reservoir assists with establishing the priority for enhancing environments of children. © 2010 Elsevier B.V.

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