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COMMENTARY: Bias in the US Environmental Protection Agency's Baseline Health Risk Assessment Supporting the Decision to Require Dredging of PCB-Bearing Sediments from the Hudson River

Published online by Cambridge University Press:  02 August 2007

Robert A. Michaels  and
Uriel M. Oko
Robert A. Michaels
Affiliation:
RAM TRAC Corporation, Schenectady, New York
Uriel M. Oko
Affiliation:
Recycle Management, Glenmont, New York
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Abstract

The US Environmental Protection Agency's (EPA) baseline Hudson River health risk assessment (HRA) is evaluated and found to be biased toward keeping polychlorinated biphenyls (PCBs) in sediments. The HRA systematically mis-quantified parameters, underestimating PCB movement from sediments to water and from water to air. The EPA excluded from its analysis all mono- and dichlorinated PCB congeners, which EPA subsequently estimated at one-third of total PCB mass in the river, and excluded dissolved and colloidal PCB. The EPA included silt-adsorbed PCB, but overestimated the rate at which it would settle out of the water column by inappropriately basing the rate on Stokes' Law for more massive spherical particles. Flat clay particles settle more slowly with a longer path length and residence time. The EPA omitted electrostatic charges on clay particles that separate them, preventing agglomeration and maintaining clay in suspension; they also assumed that particles never “reflect” back into the water column after settling, likewise underestimating PCB concentrations in water. Also omitted was PCB codistillation, in which PCBs at low bulk concentrations preferentially distribute to the air-water interface, accelerating PCB transfer from water to air. Indeed, EPA cited empirical data showing more rapid PCB water-to-air transfer, but reduced its effect on the HRA, reducing the transfer coefficient by averaging in lower modeled PCB transfer coefficients that ignored codistillation. Finally, EPA omitted PCB release to the atmosphere from hot water in cooling towers in communities along the Hudson River. Water at cooling tower temperatures may release PCB into the air more than 10 times faster than rates determined from the surface of cold water and multiple orders of magnitude more rapidly than in EPA's models. Together, EPA's procedures reduced airborne PCB concentrations from above to below de minimis concentrations. This, in turn, eliminated the requirement for EPA's HRA to quantify inhalation risks posed by airborne PCBs; the HRA, therefore, considered airborne PCBs, but attributed zero health risk to them.

Environmental Practice 9:96–111 (2007)

Type
FEATURES & REVIEWS
Information
Environmental Practice , Volume 9 , Issue 2 , June 2007 , pp. 96 - 111
Copyright
© 2007 National Association of Environmental Professionals

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References

Agency for Toxic Substances and Disease Registry. 2000. Toxicological Profile for Polychlorinated Biphenyls (PCBs). US Department of Health and Human Services, Public Health Service, Atlanta, GA, 948 pp.
Anonymous. 2001. Great Lakes Show Signs of Exhaling Contaminants. EM Magazine, Air & Waste Management Association, December, p. 9.
Baibergenova, A., R. Kudyakov, M. Zdeb, and D. O. Carpenter. 2003. Low Birth Weight and Residential Proximity to PCB-Contaminated Waste Sites. Environmental Health Perspectives 111:1352–1357.Google Scholar
Baker, J. E., W. F. Bohlen, R. Bopp, B. Brownawell, T. K. Collier, K. J. Farley, W. R. Geyer, and R. Nairn. 2001. PCBs in the Upper Hudson River: The Science behind the Dredging Controversy. White paper prepared for the Hudson River Foundation, 47 pp. Also available at http://www.seagrant.sunysb.edu/HEP/archive/hrfpcb102901.pdf.
Bernhardt, E. S., et al. 2005. Synthesizing US River Restoration Efforts. Science 308:636–637.Google Scholar
Buckley, E. H., and T. J. Tofflemire. 1983. Uptake of Airborne PCBs by Terrestrial Plants near the Tailwater of a Dam. Proceedings of the National Conference on Environmental Engineering, ASCE Specialty Conference, pp. 662–669, July 6–8.
Cappiello, D. 2001. New EPA Plan Dredges More PCBs: Agency Raises Estimate by 50 Percent on New Data from GE. Times Union Newspaper, Albany, NY, December 6, p. B5.
Carpenter, D. O. 1998. Polychlorinated Biphenyls and Human Health. International Journal of Occupational Medicine and Environmental Health 11:291–303.Google Scholar
Carpenter, D. O. 2005. Hospitalization Rates for Coronary Heart Disease in Relation to Residence near Areas Contaminated with Persistent Organic Pollutants and Other Pollutants. Environmental Health Perspectives 113(6):756–761.Google Scholar
Carpenter, D. O.; T. Nguyen, L. Le, A. Baibergenova, and R. Kudyakov. 2003. Profile of Health Effects Related to Proximity to PCB-Contaminated Hazardous Waste Sites in New York. Fresenius Environmental Bulletin 12:173–180.Google Scholar
Chase, K. H.; O. Wong, D. Thomas, B. W. Berney, and R. K. Simon. 1982. Clinical and Metabolic Abnormalities Associated with Occupational Exposure to Polychlorinated Biphenyls (PCBs). Journal of Occupational Medicine 24(2):109–114.Google Scholar
Choi, W., S. Y. Eum, Y. W. Lee, B. Hennig, L. W. Robertson, and M. Toborek. 2003. PCB 104-Induced Proinflammatory Reactions in Human Vascular Endothelial Cells: Relationship to Cancer Metastasis and Atherogenesis. Toxicological Science 75:47–56.Google Scholar
Harza Engineering Co. 1992. Fort Edward Dam PCB Remnant Deposit Containment Environmental Monitoring Program: Report of 1991 Results. Harza Engineering Company, Chicago, IL.
Hennig, B., B. D. Hammock, R. Slim, M. Toborek, V. Saraswathi, and L. W. Robertson. 2002. PCB-Induced Oxidative Stress in Endothelial Cells: Modulation by Nutrients. International Journal of Hygiene and Environmental Health 205:95–102.Google Scholar
Historically Black Colleges & Universities/Minority Institutions. 2007. Environmental Technology Consortium at Clark Atlanta University and Northern Arizona University. http://jan.ucc.nau.edu/doetqp/courses/env440/env440_2/lectures/lec19/lec19.html.
Integrated Atmospheric Deposition Network. 2000. Atmospheric Deposition of Toxic Substances to the Great Lakes: IADN Results to 1996. Environment Canada and the US Environmental Protection Agency, EPA 905-R-00004, 126 pp.
Lucier, G. W. 1991. Humans are a Sensitive Species to Some of the Biochemical Effects of Structural Analogs of Dioxin. Environmental Toxicology and Chemistry 10:727–735.Google Scholar
New York State Department of Environmental Conservation. 1997. New York State DAR-1: Guidelines for the Control of Toxic Ambient Air Contaminants. New York State Department of Environmental Conservation, Albany, NY, 62 pp.
New York State Department of Environmental Conservation. 2000. Hudson River Sediment and Biological Survey. New York State Department of Environmental Conservation, Division of Water, Albany, NY, 19 pp. Also available at http://www.dec.state.ny.us/website/dow/bwam/hrsb2000.pdf.
New York State Department of Environmental Conservation. 2003. DAR-1 AGC/SGC Tables. New York State Department of Environmental Conservation, Albany, NY, 59 pp.
Oko, U., and C. Oko. 2001. Dr. Oko's Petition for Full Party Status—Response to PSEG, in the Matter of the Application of PSEG Power New York, Inc. for a State Pollution Discharge Elimination System Permit, State Air Facilities Permit and PSD Permit. Petition by Uriel M. Oko and Carol Oko with consulting assistance from Robert Michaels, RAM TRAC Corporation, December 18, 12 pp.
Paquin, J. 2001. Insights into the Origin, Movement, and Capture of PCB DNAPL Contamination at the Smithville Site [Ontario, Canada]. Proceedings of the Fractured Rock 2001 International Conference, 10 pp., March 25–28.
PSEG Power New York. 2001. Multipathway Risk Assessment for Bethlehem Energy Center Project. ENSR Corporation, Acton, MA, June.
Shavit, U., S. Moltchanov, and Y. Agnon. 2003. Particles Resuspension in Waves Using Visualization and PIV Measurements: Coherence and Intermittency. International Journal of Multiphase Flow 29(7):1183–1192.Google Scholar
Slim, R., M. Toborek, L. W. Robertson, and B. Hennig. 1999. Antioxidant Protection against PCB-Mediated Endothelial Cell Activation. Toxicological Science 52:232–239.Google Scholar
Stehr-Green, P. A., E. Welty, G. Steele, and K. Steinberg. 1989. Evaluation of Potential Health Effects Associated with Serum Polychlorinated Biphenyl Levels. Environmental Health Perspectives 70:255–259.Google Scholar
Taylor, P. R., J. M. Stelma, and C. E. Lawrence. 1989. The Relation of Polychlorinated Biphenyls to Birth Weight and Gestational Age in the Offspring of Occupationally Exposed Mothers. American Journal of Epidemiology 129:395–406.Google Scholar
US Environmental Protection Agency. 1999. HRA, Mid-Hudson River, Phase 2 Report—Further Site Characterization and Analysis. Volume 2F—A Human Health Risk Assessment for the Mid-Hudson River, Hudson River PCBs Reassessment FS. TAMS Consultants, Bloomfield, NJ, 30 pp. plus appendices.
US Environmental Protection Agency. 2000a. Revised HRA, Mid- and Upper Hudson River, Phase 2 Report—Further Site Characterization and Analysis. Volume 2F—A Human Health Risk Assessment, Hudson River PCBs Reassessment FS. TAMS Consultants, Bloomfield, NJ, 128 pp. plus appendices.
US Environmental Protection Agency. 2000b. Revised HRA, Mid- and Upper Hudson River, Appendix E: Engineering Analysis, Section 6, Technical Memorandum: Semiquantitative Analysis of Water Quality Impacts Associated with Dredging Activities. Hudson River PCBs Reassessment FS. TAMS Consultants, Bloomfield, NJ, pp. 33–67.
US Environmental Protection Agency. 2006a. Actions Prior to EPA's February 2002 Rod [Record of Decision]. Figure 2-2, Hudson River PCB Site History. http://www.epa.gov/hudson/actions.htm.
US Environmental Protection Agency. 2006b. Hudson River PCBs. http://www.epa.gov/hudson/reports.htm.