Factsheet - Use of effect-based monitoring for the assessment of risks of low-level mixtures of chemical in water on man and the environment

“What are bioassays? In the context of Effect-Based Monitoring for water quality assessment, it is common practice to apply in vitro assays using mammalian cell lines, bacterial strains or low complexity in vivo bioassays. Bioassays are commonly applied to water samples, including wastewater, recycled water and drinking water.
Why use bioassays? There is increasing concern about the presence of micropollutants in the aquatic environment, with micropollutants detected in both source and treated drinking water. Further, treatment processes such as disinfection can result in the formation of disinfection by-products (DBPs) and other micropollutant transformation products. The complex mixture of chemicals in water means that targeted chemical analysis alone cannot assess the total chemical burden. Bioassays are recommended to complement chemical analysis for water quality monitoring as they can detect all chemicals in an environmental or water sample that are active in an applied bioassay, including both known and unknown chemicals (Brack et al. 2019). They can also account for mixture effects and group chemicals that elicit the same mode of action. Effect-based monitoring is often applied as a screening tool, but bioassay results can be used as input for risk-based monitoring programs.”

(Citation: Neale, P., Leusch, F., Escher, B. – Factsheet – Use of effect-based monitoring for the assessment of risks of low-level mixtures of chemical in water on man and the environment – GWRC EBM in WSP – WP3.1(2020))