From non-target screening to risk assessment

Non-target screening, bioassays and computer modelling can provide information about the structure, concentration and toxicity of unknown substances in water. Until now, these chemical, biological and computing methods have often been used separately. By integrating them, drinking water laboratories and drinking water utilities can strengthen and accelerate risk-based monitoring.

Proven methods deployed separately

The identity and potential harmfulness of many of the substances present in surface water and groundwater are still unknown. The concentrations can vary widely. For water quality purposes, it is extremely important to identify these unknown substances and to be able to conduct a risk assessment. That requires information about the chemical structure, concentrations, harmfulness and risk to health, and the environment where the substances are found. The main challenge consists of collecting and assessing this large amount of information. Currently, high resolution mass spectrometry is used for chemical analysis and existing data, bioassays and computer methods are used to estimate harmfulness. These techniques are often deployed separately, which means that the added value and possibilities of these methods are not used to their full potential.

From unknown substance to targeted risk assessment

In this project, we are developing an integrated approach with high-resolution mass spectrometry, bioassays and computing methods to combine their strengths and enhance the applicability of non-target screening for the risk assessment of emerging and unknown substances, and mixtures of those substances. Extra attention has been paid here to the uncertainties associated with the forecasts.

Improved risk-based monitoring

Integrating different techniques allows the risk-based monitoring of water quality to be used in more targeted ways. This helps drinking water laboratories and drinking water utilities to set priorities on the basis of potential health risks from emerging and unknown substances, and mixtures of those substances.

Figure 1. From non-target screening data to risk assessment. The uncertainty of the prediction and risk assessment varies depending on the available information.