K Hund-Rinke | PubMed Health

PubMed2003

Underlying issues including approaches and information needs in risk assessment.

Risk assessment requires a delicate consideration of the factors modifying exposure and effects. In this contribution a review is given of the qualitative and quantitative information needs that are essential for a proper risk assessment. The focus is on the details of metal exposure and exposure assessment, following the themes of environmental, physicochemical, and biological components that define exposure. Apart from a description of the principle processes and pathways, exposure assessment is placed in the context of risk assessment and its use in policy and regulatory decision making.

Animals↗

PubMed2003

Underlying issues in bioaccessibility and bioavailability: experimental methods.

This article presents experimental designs focusing on assessing of the bioavailability of metals in aquatic organisms, soil organisms, microorganisms, plants, birds, and mammals. Standardized test systems receive the greatest emphasis. With regard to microorganisms, animals, and plants, the study concentrates on toxicity as an indicator for bioavailability. In respective test procedures, results are usually calculated for total chemical concentrations; chemical analyses are not commonly in routine assessments. For soil organisms chiefly exposed by the water pathway, the bioavailable fraction of contaminants can be roughly determined by chemical analyses in aqueous soil extracts simulating soil pore water concentrations. Human toxicity can be determined using adequate in vitro test designs. In addition to experimental designs, results from the literature dealing with specific problems of bioavailability are presented.

Animals↗