Biomarkers and integrated environmental risk assessment: are there more questions than answers?

The introduction of the European Commission's Water Framework Directive (WFD; 2000/60/EC) established a new era in environmental risk assessment. In addition to incorporating the compliance of chemical quality standards, the key objective of the WFD is the general protection of the aquatic environment in its entirety. This new approach emphasizes the need for an integrated environmental risk assessment and offers the potential for the incorporation of biological effects measures, including the use of biomarkers in this process. Biomarkers have been suggested as practical tools for environmental management for a number of decades, but their inclusion has not been universally accepted because of a number of unanswered questions regarding sensitivity, practicality, and reproducibility. With this in mind, this paper addresses these potential questions and shows how, by taking a weight-of-evidence approach, biomarkers may be successfully incorporated within environmental risk assessment frameworks such as the WFD.

An integrated biomarker-based strategy for ecotoxicological evaluation of risk in environmental management.

Environmental impacts by both natural events and man-made interventions are a fact of life; and developing the capacity to minimise these impacts and their harmful consequences for biological resources, ecosystems and human health is a daunting task for environmental legislators and regulators. A major challenge in impact and risk assessment, as part of integrated environmental management (IEM), is to link harmful effects of pollution (including toxic chemicals) in individual sentinel animals to their ecological consequences. This obstacle has resulted in a knowledge-gap for those seeking to develop effective policies for sustainable use of resources and environmental protection. Part of the solution to this problem may lie with the use of diagnostic clinical-type laboratory-based ecotoxicological tests or biomarkers, utilising sentinel animals as integrators of pollution, coupled with direct immunochemical tests for contaminants. These rapid and cost-effective ecotoxicological tools can provide information on the health status of individuals and populations based on relatively small samples of individuals. In the context of ecosystem status or health of the environment, biomarkers are also being used to link processes of molecular and cellular damage through to higher levels (i.e., prognostic capability), where they can result in pathology with reduced physiological performance and reproductive success. Complex issues are involved in evaluating environmental risk, such as the effects of the physico-chemical environment on the speciation and uptake of pollutant chemicals and inherent inter-individual and inter-species differences in vulnerability to toxicity; and the toxicity of complex mixtures. Effectively linking the impact of pollutants through the various hierarchical levels of biological organisation to ecosystem and human health requires a pragmatic integrated approach based on existing information that either links or correlates processes of pollutant uptake, detoxication and pathology with each other and higher level effects. It is further proposed here that this process will be facilitated by pursuing a holistic or whole systems approach with the development of computational simulation models of cells, organs and animals in tandem with empirical data (i.e., the middle-out approach). In conclusion, an effective integrated environmental management strategy to secure resource sustainability requires an integrated capability for risk assessment and prediction. Furthermore, if such a strategy is to influence and help in the formulation of environmental policy decisions, then it is crucial to demonstrate scientific robustness of predictions concerning the long-term consequences of pollution to politicians, industrialists and environmental managers; and also increase stakeholder awareness of environmental problems.

Distinctive emergency department usage for injury for workers' compensation cases in Utah in 1996.

To compare emergency department services paid by worker's compensation (WC) with services paid by other payers, a state database of 72,747 emergency department visits for injured adults (ages 21 to 54) in 1996 in Utah was analyzed. WC visits accounted for 21.6% (15,704) of all adult injury visits. The mean emergency department charge for WC visits was $282, and the admission rate was 17 per 1000 visits. The mean charge for other payers was $334, and the admission rate was 43 per 1000 visits. Differences were also found between these groups for Injury Severity Scores and diagnoses. In summary, WC emergency department usage was associated with less severe injuries than was emergency department usage for other payers in Utah in 1996.

Radioactivity in two tide-washed marsh areas in the eastern Irish Sea: a radiological assessment.

The doses received by man from exposure to artificial radionuclides deposited onto marsh land during tidal inundation on the English side of the Solway Firth and the Dee Estuary have been assessed. The range of total doses received by the different marsh user groups was similar in both study areas, varying from < 1 microSv year-1 to approximately 55 microSv year-1, with total dose dominated by the contribution from external exposure (generally 80% of the total). The maximum doses in both study areas were received by people working on the marshes and are well below the annual dose limit recommended by ICRP for members of the public (1 mSv year-1). The largest dose estimated (56 microSv year-1) is only 6% of the recommended dose limit.