Effect-based monitoring of water quality with bioassays

Bioassays can measure different health effects

Bioassays make use of organisms, cells and bacteria, and are an effective instrument in investigating the effects of chemicals on humans and the environment (ecotoxicity). Bioassays measure the combined effect of chemicals present in chemical mixtures, without the need of having information about which chemicals are present and in which concentrations. Bioassays can be conducted, among others, on drinking water, wastewater, surface water and groundwater.

There are bioassays available for different harmful effects, for example, on the genetic material (DNA), the nervous system, the endocrine system, the metabolism and oxidative stress (damage of healthy cells and tissues by reactive substances). Since water can contain many different chemicals, water-quality monitoring usually requires the conduct of more than a single bioassay. Our experts can offer advice on which tests are best suited for your research question.

Different bioassays available

Our laboratory carries out the Ames fluctuation test and/or the umu test to study the effects on the DNA. We can, jointly with other actors, conduct the p53-CALUX and micronucleus test, which means we can determine all of the mechanisms through which chemicals can cause damage to the DNA.

Bioassays focused on the effects on the endocrine system, metabolism and oxidative stress are often reporter gen assays that are very specific to a particular process. Examples of bioassays for these effects are, respectively, the ER-CALUX, the PAH-CALUX and the Nrf2-CALUX. We can supervise the conduct of CALUX bioassays, and identify and interpret the results.

We also research the effects on organ systems, such as the nervous system and the immune system, in which we explore which bioassays are available and appropriate for water-quality measurements. We stay up to date on developments so as to provide the water sector with current knowledge for the determination of effects of specific chemical groups, including pesticides.

Choice of bioassays and results interpretation

We can offer advice on which bioassays are best suited for your research question. We have collaborated at the national and international level on the development of decision aids for bioassays, from source to tap, and in the whole water sector, including water reuse. A staged strategy can be applied to determine both the water quality of a drinking water source as well as the effectiveness of a water treatment process. By using bioassays for the purpose of screening, water samples can be prioritised for further research using more advanced bioassays, whether or not in combination with chemical analysis and computer models, to predict toxicity. We work on research to improve the interpretation of bioassay measurement data using trigger values and apply these in practice.