Trigger value data gaps I and II

There are a lot of advantages to testing water quality with in vitro bioassays but this technique can only be properly applied if the bioassay responses can be compared with ‘effect-based trigger values’ (EBT). This study determines these values for a number of bioassays used widely in water quality monitoring.

These EBTs can be applied to determine which bioassay responses warrant follow-up research and management measures targeting the possible risks for human health. In this way, these tests will be better adapted for use in practice. On the basis of available data, it was decided to derive EBTs for four different Chemical Activated LUciferase gene eXpression (CALUX) in vitro bioassays. In addition, the study will look at whether EBTs can also be derived for bioassays that determine DNA damage. It is important to have enough available data in order to arrive at a useful and reliable value. If the EBT is too high, there is a risk of health risks going undetected; if the EBT is too low, further investigation is conducted, often unnecessarily, to determine the cause and risk. An adequate picture of the chemical water quality of drinking water sources and the rapid detection of new contaminants can help to safeguard drinking water quality.

Alongside the determination of EBTs, these values were also evaluated and further refined by using kinetic models. These results can be used to make the in vitro bioassay responses better predictors of potential health effects and, in this way, to safeguard drinking water quality.