Dataset Information

Application of new statistical distribution approaches for environmental mixture risk assessment: A case study.

ABSTRACT:

Objectives

There is growing evidence that single substances present below their individual thresholds of effect may still contribute to combined effects. In component-based mixture risk assessment (MRA), the risks can be addressed using information on the mixture components. This is, however, often hampered by limited availability of ecotoxicity data. Here, the possible use of ecotoxicological threshold concentrations of no concern (i.e. 5th percentile of statistical distribution of ecotoxicological values) is investigated to fill data gaps in MRA.

Methods

For chemicals without available aquatic toxicity data, ecotoxicological threshold concentrations of no concern have been derived from Predicted No Effect Concentration (PNEC) distributions and from chemical toxicity distributions, using the EnviroTox tool, with and without considering the chemical mode of action. For exposure, chemical monitoring data from European rivers have been used to illustrate four realistic co-exposure scenarios. Based on those monitoring data and available ecotoxicity data or threshold concentrations when no data were available, Risk Quotients for individual chemicals were calculated, to then derive a mixture Risk Quotient (RQmix).

Results

A risk was identified in two of the four scenarios. Threshold concentrations contribute from 24 to 95% of the whole RQmix; thus they have a large impact on the predicted mixture risk. Therefore they could only be used for data gap filling for a limited number of chemicals in the mixture. The use of mode of action information to derive more specific threshold values could be a helpful refinement in some cases.

SUBMITTER: Kienzler A

PROVIDER: S-EPMC6839615 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Publications

Application of new statistical distribution approaches for environmental mixture risk assessment: A case study.

Kienzler Aude A Bopp Stephanie S Halder Marlies M Embry Michelle M Worth Andrew A

The Science of the total environment 20190721

<h4>Objectives</h4>There is growing evidence that single substances present below their individual thresholds of effect may still contribute to combined effects. In component-based mixture risk assessment (MRA), the risks can be addressed using information on the mixture components. This is, however, often hampered by limited availability of ecotoxicity data. Here, the possible use of ecotoxicological threshold concentrations of no concern (i.e. 5th percentile of statistical distribution of ecot ...[more]

PMID: 31357034

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Dataset Information

Application of new statistical distribution approaches for environmental mixture risk assessment: A case study.

Objectives

Methods

Results

Publications

Application of new statistical distribution approaches for environmental mixture risk assessment: A case study.

Similar Datasets

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