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New Orleans, LA, United States

Mielke H.W.,Tulane University | Mielke H.W.,Xavier Universities | Covington T.P.,The New School | 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. Source

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. Source

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. Source

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. Source

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. Source

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