In recent years, a significant number of environmental studies have been conducted in New Orleans, LA and surrounding Gulf Coast areas due in part to the occurrence of hurricanes Katrina and Rita. Data collected from studies in the New Orleans area indicate that inorganic contaminants including arsenic (As), iron (Fe), lead (Pb), and vanadium (V); high concentration of bioaerosols, particularly Cladosporium and Aspergillus, and several organic pollutants (PAHs, pesticides, and volatiles) may pose a risk to human health in New Orleans. While many of these results resemble historical data, a current quantitative exposure assessment has not been conducted. We engaged in one such assessment for lead (Pb) contamination in surface soils. We used Pb concentrations in surface soils (<5 cmdeep) from New Orleans and quantitative data on soil ingestion using the USEPA terrestrial wildlife model to imitate lifestyle movement (e.g., school to home to daycare) to estimate child exposure to Pb contributed by soil. Our results suggest that Pb exposure from soil could range from 1.4 μg/day to 102 μg/day for our study area within urbanNew Orleans. These data are concerning because children exposed to >33.5 μg/d Pb may cause their blood-Pb levels to exceed the Centers for Disease Control and Prevention (CDC) threshold for blood-Pb of 10 μg/dL. It has generally been accepted that a more protective blood Pb concentration threshold of 6 - μg/dL is warranted. Using the 6 - μg/dL threshold puts children exposed to as little as 20.2 μg/day Pb at risk.
KeywordsMetalsLeadNew OrleansExposure Model
L. M. Chiodo, S. W. Jacobson and J. L. Jacobson, “Nuerodevelopmental Effects of Postnatal Lead Exposure at Very Low Levels,” Neurotoxicology and Teratology, Vol. 26, No. 3, 2004, pp. 359-371. doi:10.1016/j.ntt.2004.01.010
H. W. Mielke and P. L. Reagan, “Soil Is an Important Source of Childhood Lead Exposure,” Environmental Health Perspectives, Vol. 106, Suppl. 1, 1998, pp. 217-229. doi:10.1289/ehp.98106s1217
S. Skerfving and I. A. Bergdahl, “Lead,” In: G. F. Nordberg, B. A. Fowler, M. Nordberg and L. T. Friberg, Eds., Handbook on the Toxicology of Metals, 3rd Edition, Academic Press, Burlington, 2007. doi:10.1016/B978-012369413-3/50086-0
R. A. Goyer, “Toxic Effects of Metals,” In: C. D. Klaassen, Ed., Cassarett and Doull’s Toxicology, The Basic Science of Poisons, 5th Edition, McGraw-Hill, New York, 1996.
H. W. Mielke, C. R. Gonzales, M. K. Smith and P. W. Mielke, “The Urban Environment and Children’s Health: Soils as an Integrator of Lead, Zinc, and Cadmium in New Orleans, Louisiana, USA,” Environmental Research Section A. Vol. 81, No. 2, 1999, pp. 117-129. doi:10.1006/enrs.1999.3966
M. B. McBride, “Trace and Toxic Elements in Soils,” In: M. B. McBride, Ed., Environmental Chemistry of Soils, Oxford University Press, New York, 1994, pp. 308-341.
R. L. Canfield, C. R. Henderson, D. A. Cory-Slechta, C. Cox, T. A. Jusko and B. P. Lanphear, “Intellectual impairment in Children with Blood Lead Concentrations below 10 μg Per Deciliter,” New England Journal of Medicine, Vol. 348, No. 16, 2003, pp. 1517-1526. doi:10.1056/NEJMoa022848
Center for Disease Control and Prevention, “Preventing lead Poisoning in Young Children,” US Department of Health and Human Services, Public Health Service, Center for Disease Control and Prevention, Atlanta, 1991.
S. M. Presley, T. R. Rainwater, G. P. Austin, S. G. Platt, J. C. Zak, G. P. Cobb, E. J. Marsland, K. Tian, B. Zhang, T. A. Anderson, S. B. Cox, M. T. Abel, B. D. Leftwich, J. B. Huddleston, R. M. Jetter and R. J. Kendall, “Assessment of Pathogens and Toxicants in New Orleans, LA Following Hurricane Katrina,” Environmental Science and Technology, Vol. 40, No. 2, 2006, pp. 468-474. doi:10.1021/es052219p
J. H. Pardue, W. M. Moe, D. McInnis, L. J. Thibodeaux, K. T. Valsaraj, E. Maciasz, I. van Heerden, N. Korevec and Q. Z. Yuan, “Chemical and Microbiological Parameters in New Orleans Floodwater Following Hurricane Katrina,” Environmental Science and Technology, Vol. 39, No. 22, 2005, pp. 8591-8599. doi:10.1021/es0518631
C. Adams, E. C. Witt, J. Wang, D. K.Shaver, D. Summers, Y. Filali-Meknassi, H. Shi, R. Lunaand N. Anderson, “Chemical Quality of Depositional Sediments and Associated Soils in New Orleans and the Louisiana Peninsula Following Hurricane Katrina,” Environmental Science and Technology, Vol. 41, No. 10, 2007, pp. 3437-3443. doi:10.1021/es0620991
G. M. Solomon, M. Rotkin-Ellman, “Contaminants in New Orleans Sediment: An Analysis of EPA Data,” Natural Resources Defense Council, 2006. http://www.nrdc.org/health/effects/katrinadata/sedimentepa.pdf
E. C. Witt III, C. Adams, J. Wang, D. K. Shaver, D. K. and Y. Filani-Meknassi, “Selected Chemical Composition of Deposited Sediments in the Flooded Areas of New Orleans Following Hurricane Katrina,” Science and Storms: The USGS Response to the Hurricanes of 2005, 2006. http://pubs.usgs.gov/circ/1306/pdf/c1306_ch7_b.pdf
M. T. Abel, S. M. Presley, T. R. Rainwater, G. P. Austin, S. B. Cox, L. N. McDaniel, E. J.Marsland, B. D. Leftwich, T. A. Anderson, R. J. Kendall and G. P. Cobb, “Spatial and Temporal Evaluation of Metal Concentrations in Soils and Sediments from New Orleans, Louisiana, USA, Following Hurricanes Katrina and Rita,” Environmental Toxicology and Chemistry Vol. 26, No. 10, 2007, pp. 2108-2114. doi:10.1897/06-595R.1
G. P. Cobb, M. T. Abel, T. R. Rainwater, G. P. Austin, S. B. Cox, R. J. Kendall, E. J. Marsland, T. A. Anderson, B. D. Leftwich, J. C. Zak and S. M. Presley, “Metal Distributions in New Orleans Following Hurricanes Katrina and Rita: A Continuation Study,” Environmental Science and Technology, Vol. 40, No. 15, 2006, pp. 4571-4577. doi:10.1021/es060041g
B. C. Suedel, J. A. Steevens, A. J. Kennedy, S. M. Brasfield and G. L. Ray, “Environmental Consequences of the Failure of the New Orleans Levee System during Hurricane Katrina: Chemical, Toxicological, and Benthic Community Analysis,” Environmental Science and Technology, Vol. 41, No. 7, 2007, pp. 2594-2601. doi:10.1021/es061977s
M. T.Abel, S. M. Presley, T. R. Rainwater, G. P. Austin, S. B. Cox, L. N. McDaniel, R. Rigdon, T. Goebel, R. Zartman, B. D. Leftwich, T. A. Anderson, R. J. Kendall, G. P. Cobb, “Lead Distributions and Risks in New Orleans Following Hurricanes Katrina and Rita,” Environmental Toxicology and Chemistry, Vol. 29, No. 7, 2010, pp. 1429-1437. doi:10.1002/etc.205
United States Environmental Protection Agency, Soil Screening Levels, “Region 6 Corrective Action Strategy (CAS) RCRA Projects,” USEPA, Dallas, 2005. http://www.epa.gov/earth1r6/6pd/rcra_c/pd-o/riskman.htm
“United States Environmental Protection Agency Region 6 High Priority Bright Line Screening Table,” USEPA, Dallas, 2000. http://www.epa.gov/Arkansas/6pd/rcra_c/pd-o/capp-dhpblt.pdf
N. E. Klepeis, W. C. Nelson, W. R. Ott, J. P. Robinson, A. M. Tsang, P. Switzer, J. V. Behar, S. C. Hern and W. H. Engelmann, “The National Human Activity Pattern Survey (NHAPS): A Resource for Assessing Exposure to Environmental Pollutants,” Journal of Exposure and Analytical Environmental Epidemiology, Vol. 11, No. 3, 2001, pp. 231-252. doi:10.1038/sj.jea.7500165
T.McCurdy and S. E. Graham, “Using Human Activity Data in Exposure Models: Analysis of Discriminating Factors,” Journal of Exposure and Analytical Environmental Epidemiology, Vol. 13, No. 4, 2003, pp. 294-317. doi:10.1038/sj.jea.7500281
E. A.Cohen Hubal, L. S. Sheldon, J. M. Burke, T. R. McCurdy, M. R. Berry, M. L. Rigas, V. G. Zartarianand N. C. G. Freeman, “Children’s Exposure Assessment: A Review of Factors Influencing Children’s Exposure, and the Data Available to Characterize and Assess That Exposure,” Environmental Health Perspectives, Vol. 108, No. 6, 2000, pp. 475-486. doi:10.1289/ehp.00108475
E. J. Stanek III and E .J. Calabrese, “Daily Soil Ingestion Estimates for Children at a Superfund Site,” Risk Analysis, Vol. 20, No. 5, 2000, pp. 627-635. doi:10.1111/0272-4332.205057
M. A. Jayjock, C. F. Chaisson, S. Arnold and E. J. Dederick, “Modeling Framework for Human Exposure Assessment,” Journal of Exposure Analysis and Environmental Epidemiology, Vol. 17, No. S1, 2007, pp. S81-S89. doi:10.1038/sj.jes.7500580
Risk Assessment Forum. USEPA, “Guidelines for Exposure Assessment,” Federal Register, Vol. 57, No. 104, 1992, pp. 22888-22938.
United States Environmental Protection Agency, “Acid Digestion of Sludges, Solids and Soil,” SW-846. Pt 1; Office of Solid and Hazardous Wastes, USEPA, Cincinnati, 1996.
United States Environmental Protection Agency, “Inductively Coupled Plasma Atomic Emission Spectrometry” SW-846. Pt 1; Office of Solid and Hazardous Wastes, USEPA, Cincinnati, 1996.
United States Environmental Protection Agency, “Methods for the Determination of Metals in Environmental Samples”, Supplement I, USEPA, Cincinnati, 1994.
A. D. Eaton, A. S. Clesceri and A. E. Greenberg, “Standard Methods for the Examination of Water and Wastewater,” 19th Edition, 1995.
B. E. Sample, M. S. Aplin, R. A. Efroymson, G. W. Suter II and C. J. E. Welsh, “Methods and Tools for Estimation of the Exposure of Terrestrial Wildlife to Contaminants,” Environmental Sciences Division, Publication No. 4650, 1997.
H. W. Mielke, D. Dugas, P. W. Mielke Jr., K. S. Smith, S. L. Smith and C. R. Gonzales, “Associations between soil Lead and Childhood Blood Lead in Urban New Orleans and Rural Lafourche Parish of Louisiana.” Environmental Health Perspectives, Vol. 105, No. 9, 1997, pp. 950-954. doi:10.1289/ehp.97105950
M. Pueyo, J. Sastre, E. Hernandez, M. Vidal, J. F. Lopez-Sanchez and G. Rauret, “Heavy Metals in the Environment Prediction of Trace Element Mobility in Contaminated Soils by Sequential Extraction,” Journal of Environmental Quality, Vol. 32, No. 6, 2003, pp. 2054-2066. doi:10.2134/jeq2003.2054
R. A. Schoof, M. K. Butcher, C. Sellstone, R. W. Ball, J. R. Fricke, V. Keller and B. Keehn, “An Assessment of Lead Absorption from Soil Affected by Smelter Emissions,” Environmental Geochemistry and Health, Vol. 17, No. 4, 1995, pp. 189-199. doi:10.1007/BF00661331