Application of effect-directed analysis to identify mutagenic nitrogenous disinfection by-products of advanced oxidation drinking water treatment
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Advanced oxidation processes are important barriers for organic micropollutants in (drinking) water treatment. It is however known that medium pressure UV/H2O2 treatment may lead to mutagenicity in the Ames test, which is no longer present after granulated activated carbon (GAC) filtration. Many nitrogen-containing disinfection by-products (N-DBPs) result from the reaction of photolysis products of nitrate with (photolysis products of) natural organic material (NOM) during medium pressure UV treatment of water. Identification of the N-DBPs and the application of effect-directed analysis to combine chemical screening results with biological activity would provide more insight into the relation of specific N-DBPs with the observed mutagenicity and was the subject of this study. To this end, fractions of medium pressure UV-treated and untreated water extracts were prepared using preparative HPLC and tested using the Ames fluctuation test. In addition, high-resolution mass spectrometry was performed on all fractions to assess the presence of N-DBPs. Based on toxicity data and read across analysis, we could identify five N-DBPs that are potentially genotoxic and were present in relatively high concentrations in the fractions in which mutagenicity was observed. The results of this study offer opportunities to further evaluate the identity and potential health concern of N-DBPs formed during advanced oxidation UV drinking water treatment.
KeywordsDisinfection by-products Advanced oxidation processes Medium pressure ultraviolet technology Nitrate photolysis Effect-directed analysis Fractionation High-resolution mass spectrometry Ames fluctuation test
This study was cofinanced with TKI funding from the Topconsortia for Knowledge & Innovation (TKI’s) of the Ministry of Economic Affairs of the Netherlands.
- EPA US (2012) 2012 edition of the drinking water standards and health advisories EPA 822-S-12-001. U.S. Environmental Protection Agency, Washington, DCGoogle Scholar
- European Chemicals Agency Information on Registered Substances (2015) Available at: http://echa.europa.eu/web/guest/information-on-chemicals/registered-substances
- International Agency for Research on Cancer (IARC) (2016) Agents Classified by the IARC Monographs, Volumes 1–115 Available at: http://monographs.iarc.fr/ENG/Classification
- National Library of Medicine (US) (2011) Hazardous Substances Data Bank [Internet] Available at: http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?HSDB
- OECD (2013) QSAR Toolbox for Grouping Chemicals into Categories version 22.214.171.124. Available at: http://www.qsartoolbox.org/download
- Rijksinstituut voor Volksgezondheid en Milieu (RIVM) (2015) Risico’s van Stoffen. Available at: http://www.rivm.nl/rvs.
- SZW (2016) SZW lijst van kankerverwekkende, mutagene en voor de voortplanting giftige stoffen, Ministerie van Sociale Zaken en Werkgelegenheid. Staatscourant 43Google Scholar
- TERA (Toxicology Excellence for Risk Assessment) (2010) International Toxicity Estimates for Risk (ITER) Database. Online. Available at: www.tera.org/iter
- United States Environmental Protection Agency Integrated Risk Information System (IRIS) (2016) Available at: https://www.epa.gov/iris
- Wolf S, Schmidt S, Müller-Hannemann M, Neumann S (2010) In silico fragmentation for computer assisted identification of metabolite mass spectra. BMC Bioinf 11 doi: 10.1186/1471-2105-11-148