Evaluation of the DBP formation potential of biocides and identification of knowledge gaps in environmental risk assessment

Abstract

AbstractDisinfectants and preservatives used as biocides may contain or release active substances (a.s.) that can form by-products with the surrounding matrices during their application which may be released into the environment. Over the past 40 years, several hundred of these so-called disinfection by-products (DBPs) have been detected after applications of biocides used for disinfection. Due to intensive research and further development of analytical capabilities, many new DBP classes, such as iodinated DBPs (I-DBPs), halonitromethanes (HNMs), haloacetamides (HaAms), or halomethanesulfonic acids were detected worldwide in various matrices and applications. Due to the possible hazards and risks for humans and the environment, frequently occurring DBP classes, such as trihalomethanes (THM), haloacetic acids (HAA) and nitrosamines (NDMA), have already been included in many legislations and given limit values. In the European Union, biocides are assessed under the Biocidal Products Regulation 528/2012 (BPR) regarding their efficacy, potential hazards, and risks to human health and the environment. However, the available guidance for the environmental risk assessment (ERA) of DBPs remains vague. To identify knowledge gaps and to further develop the assessment scheme for the ERA of DBPs, a literature search on the multiple uses of biocides and their formation potential of DBPs was performed and the existing process for ERA was evaluated. The results show knowledge gaps on the formation of DBP in non-aqueous systems and DBP formation by non-halogen-based biocidal active substances. Based on the literature research on biocides, a possible proposal of grouping a.s. to consider their DBP formation potential is presented to simplify future ERAs. However, this also requires further research. Until then, a pragmatic approach considering the DBPs formation potential of the active substances and the identified knowledge gaps need to be established for the environmental risk assessment of DBPs in the EU. Graphical Abstract