QSAR tools and bioassays for emerging contaminants and transformation products

Problem definition

For new, emerging contaminants in drinking water sources, there are sometimes very little or no data available on their possible adverse effects on human health. There are also frequently very little or no toxicological data available on transformation products. For these ‘data-poor substances’, it is difficult, if not impossible, to make a good assessment of the potential risks they might represent to human health or the environment.

A possible solution is offered by Quantitative Structure-Activity Relationship (QSAR) tools, which can estimate a compound’s possible health and environmental effects on the basis of its structural formula. Water samples pose a problem in this regard, since they are complex samples whose identity is often unknown. In such cases, screening with bioassays offers an excellent tool for the effect-based testing of the water samples.

This project uses a combination of QSAR tools and bioassay screening in order to assess the toxicity of compounds that are detected in water, and that have as yet hardly been documented.

Developing a strategy

This project will develop a strategy to assess the risks to human health of ‘data-poor substances’. Current strategy focuses on one or two endpoints that are relevant for drinking water utilities, distinguishing between 1) read-across endpoints and 2) prioritisation for follow-up research based on structural alerts.

Faster risk assessment

For drinking water utilities this project will produce a strategy for a faster risk assessment of substances for which little or no toxicological data are available. Moreover, it will directly provide such data for a number of new, emerging contaminants and transformation products. And it will also produce a manual for the QSAR toolbox, and an evaluation of the utility of the read-across workflow of the US EPA (GenRA).