Inclusion of bioaccumulation in environmental risk assessment: An integrated approach

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:230890

Kloepper-Sams, P J ^[1]; Cowan, C E; Larson, R J; Versteeg, D J ^[2]

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1. Procter and Gamble, Strombeek-Bever (Belgium)
2. Procter and Gamble, Cincinnati, OH (United States)

Historically, the potential to bioaccumulate has been ignored in risk assessments or assessed in isolation. Bioaccumulation can be included in an integrated approach by posing two questions. (1) Is the duration of acute aquatic testing sufficient to identify effects due to direct exposure? This can be addressed by comparing T95 (time to reach 95% of steady state) with test duration. (2) Do dietary sources contribute substantially to exposure; is so, will this affect organisms higher in the food web? This can be addressed in stages. (1) A suitable QSAR can be employed to estimate the Bioconcentration Factor (BCF). Because aquatic dietary exposure to non-ionic, poorly metabolized organics is not significant for compounds with log K{sub ow} below {approximately}4.5--5, only compounds with BCF > 1,000 (log K{sub ow} {approximately}4.3) are further evaluated. (2) Predicted BCFs may be refined by measuring the predictive parameter (e.g., K{sub ow}) or the BCF. (3) If the ``parent`` BCF remains > 1,000, a food chain model is employed to derive bioaccumulation factors (BAF) which may be achieved in the food web of interest. The BAF is then combined with Predicted Environmental Concentration (PEC) values to derive a PECoral or concentration available in prey. This is then compared with a Predicted No Effect Concentration (PNEC)oral for consumer organism(s). Mammalian toxicity databases on new and HVP existing chemicals may assist in deriving the PNECoral. (4) Further refinement of the PECoral or PNECoral may be needed. Mitigating circumstances such as metabolism and reduced bioavailability must also be considered. Such an approach may be necessary for a subset of chemicals and would be tailored dependent on chemical use, release, environmental fate -- especially persistence -- and distribution.

• OSTI ID: 230890
• Report Number(s): CONF-9511137--; ISBN 1-880611-03-1
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
AQUATIC ORGANISMS
BIOLOGICAL ACCUMULATION
BIOLOGICAL AVAILABILITY
ENVIRONMENTAL IMPACTS
FOOD CHAINS
FORECASTING
ORGANIC COMPOUNDS
POLLUTION
TOXICITY
WATER POLLUTION