Risk-based decision making: The East Fork Poplar Creek case study

Journal Article · Wed Dec 01 04:00:00 EST 1999 · Environmental Toxicology and Chemistry

DOI:https://doi.org/10.1897/1551-5028(1999)018<2954:RBDMTE>2.3.CO;2· OSTI ID:20012787

Moore, D R.J.; Sample, B E; Suter, G W; Parkhurst, B R; Teed, R S

A probabilistic risk assessment revealed that methylmercury released from the US Department of Energy (DOE) Y-12 weapons facility at Oak Ridge, Tennessee, USA, poses moderate risks to mink and kingfishers residing near the receiving waters of East Fork Poplar Creek. Polychlorinated biphenyls (PCBs) released from this facility pose severe risks to mink but little risk to kingfishers. The objective of this study was to use a risk-based decision-making approach to select remedial cleanup levels for each of these contaminants. The authors conducted Monte Carlo simulations to estimate total daily intakes of each contaminant by mink (mercury and PCBs) and kingfishers (PCBs only) for a range of exposure-reduction scenarios. The resulting exposure distributions were then integrated with their respective dose-response curves to estimate postremediation risks. The results indicated that total mercury levels in surface water would need to be reduced from current levels (mean = 0.225 {micro}g/L) to 0.03 to 0.05 {micro}g/L to reduce risks to very low levels (<5% probability of {ge}20% mortality) for both mink and kingfishers. If interested parties define acceptable risk as, for example, a 20% probability of {gt} 10% mortality, then mercury levels would need to be reduced to 0.14 {micro}g/L. The PCBs analysis indicated that reducing water-borne exposures would produce only a modest reduction in risk to mink because much of the current exposure is through terrestrial exposure pathways.

• Research Organization: Cadmus Group, Ottawa, Ontario (CA)
• OSTI ID: 20012787
• Journal Information: Environmental Toxicology and Chemistry, Journal Name: Environmental Toxicology and Chemistry Journal Issue: 12 Vol. 18; ISSN ETOCDK; ISSN 0730-7268
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
BIOLOGICAL INDICATORS
FISHES
MAMMALS
METHYLMERCURY
OAK RIDGE RESERVATION
POLYCHLORINATED BIPHENYLS
RISK ASSESSMENT
STREAMS
WATER POLLUTION
WILD ANIMALS