Beyond target chemicals: Updating the NORMAN Prioritization Scheme to Support the EU Chemical Strategy with Semi-quantitative Suspect/Non-target screening data#

Authors#

Valeria Dulio, Nikiforos Alygizakis, Kelsey Ng, Emma Schymanski, Reza Aalizadeh, Sandrine Andres, Elodie Bouhoulle, Hélène Budzinski, Ľuboš Cirka, Anja Derksen, Geneviève Deviller, Anja Duffek, Mar Esperanza, Saskia Finckh, Stellan Fischer, Pablo Gago-Ferrero, Peter Haglund, Juliane Hollender, Marion Junghans, Stefan A.E. Kools, Jan Koschorreck, Benjamin Lopez, Miren Lopez De Alda, Giuseppe Mascolo, Cécile Miège, Leonard Osté, Simon O’Toole, Pawel Rostkowski, Tobias Schulze, Kerry Sims, Laetitia Six, Jaroslav Slobodnik, Pierre-François Staub, Gerard Stroomberg, Anne Togola, Katrin Vorkamp, Henk Zemmelink, Peter C. Von Der Ohe

Abstract#

Background: Prioritisation of chemical pollutants is a major challenge for environmental managers and decision-makers alike, yet it is essential to help focus the limited resources available for monitoring and mitigation actions on the most relevant chemicals. This study extends original NORMAN prioritisation scheme beyond target chemicals, presenting the integration of semi-quantitative data from retrospective suspect screening and expansion of existing exposure and risk indicators. The scheme utilises data retrieved automatically from the NORMAN Database System (NDS), including candidate compounds for prioritisation, target and suspect screening data, ecotoxicological effect data, physicochemical and other properties. Two complementary workflows using target and suspect screening monitoring data are applied to first group the substances into 6 action categories covering main regulatory needs and research actions, and then further rank the compounds using a set of exposure, hazard and risk indicators. The results from the ‘target’ and ‘suspect screening’ workflows are then combined as multiple lines of evidence to support decision-making on the identified regulatory and research actions. Results: As a proof-of-concept, the new scheme was applied to 65,690 compounds on the NORMAN Database System with a suspect screening dataset of 84 effluent wastewater samples and a target dataset of 2,579 substances, totalling >11 million data points. The final prioritisation results identified 577 compounds as high priority for further actions, 45,462 as medium priority and 308 with potentially lower priority for actions, while insufficient information was available to prioritize 18,000 compounds (due to uncertainties such as applicability domain). A high degree of agreement was observed between the categories assigned via target analysis and suspect screening-based prioritisation. Suspect screening was a valuable complementary approach to target analysis, helping to prioritize thousands of compounds that are insufficiently investigated in current monitoring programmes. Conclusions: This updated prioritization workflow responds to the increasing use of suspect screening techniques. It can be adapted to different environmental compartments and can be applied to support decision-making in the context of regulatory obligations, including the identification of specific pollutants in river basins and the marine environments, as well as the confirmation of environmental occurrence levels predicted by modelling tools.