Identification of Novel Brominated Disinfection By-Products of Concern in Drinking Water by Use of DIPIC-Frag Untargeted Screening

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1 Identification of Novel Brominated Disinfection By-Products of Concern in Drinking Water by Use of DIPIC-Frag Untargeted Screening Tena Watts November 9, 2016 Hui Peng, Paul D. Jones & John P. Giesy Title or place of presentation Date of presentation

2 Outline Introduction Research Goals Comparing methods for extraction of Br-DBPs Identification of novel Br-DBPs DIPIC-Frag Method Results Conclusion & Future Work

3 Introduction Water disinfection: process of deactivating or removing pathogens from drinking water by use of physical or chemical technologies Natural Organic Matter Inorganic Precursors Disinfectant Humic acid example Br - I - NO - 2 NH 3 Disinfection By-Products (DBPs) Cl 2 NH 2 Cl ClO 2 O 3 UV

4 Disinfection By-Products (DBPs) Trihalomethanes 0.1 mg/l Haloacetic Acids 0.08 mg/l Genotoxic, bladder cancer and adverse pregnancy outcomes (Jeong et al., 2012) > 600 compounds have been identified in drinking water Only 50% of total organic halide can be accounted for by known DBPs (Richardson et al., 2012) Many unregulated compounds have enhanced toxicities Brominated > chlorinated analogues

5 Research Questions What brominated compounds are yet to be identified in drinking water and how can we screen for them? DIPIC-Frag method Q Exactive UHRMS Optimize conditions Identify novel Br-DBPs Can we produce a semi-quantitative method that is reproducible for the analysis of real drinking water extracts?

6 Buffalo Pound Water Treatment Plant (BPWTP) Located northeast of Moose Jaw, SK 250,000 customers (Regina and Moose Jaw) Water sourced from Buffalo Pound Lake, which is known to contain a high concentration of Br -, and it is quite eutrophic 8

7 Data Independent Precursor Isolation and Characteristic Fragment Method (DIPIC-Frag) Relative Abundance Relative Abundance Relative Abundance Time (min) Precursor alignment (c) Precursor ions (a) (b) Isotope profiles of Br m/z (d) Elution profiles Time (min) Title or place of presentation 5 m/z 5 m/z DIA scanning Br fragment chromatogram Elution profiles Relative Abundance Relative Abundance Relative Abundance (e) mz mz mz Toxicology Centre NL: 4.65E5 NL: 9.66E5 NL: 4.61E Time (min) (f) m/z C 4 H 2 NBr 2-0.5ppm Isotope peaks Formula calculation m/z MS/MS for chemical (g) structures H N Br m/z Date of presentation

8 Data Independent Precursor Isolation and Characteristic Fragment Method (DIPIC-Frag) Toxicology Centre A) ph 7 ph 2 HLB C18 X C18 X X Amide WAX ESI(-) APCI(-) UHRMS UHRMS

9 Comparison of Ionization Source and Column 9.2e5 B) 1.5e6 Amide SPE ESI(-) C18 SPE ESI(-) Amide SPE APCI(-) 5.6e4 Amide column, with 0.1% NH 4 OH in water as mobile phase ESI

10 Profile of Br-DBPs in Chlorinated Drinking Water SPE, Amide Column, ESI m/z Retention time (min)

11 Profile of Br-DBPs in Chlorinated Water Compared by SPE Cartridge and ph HLB ph 2 C18 ph 2 WAX HLB C18

12 Precision of the Method: (SD/mean) 0 Log(Precision) C18 HLB WAX HLB Less variability in precision 10-15%

13 Profiles of Br-DBPs Compared by Time Point, Stage of Treatment, and SPE Cartridge C18 Oct 2015 Chlorinated C18 April 2016 Finished HLB Oct 2015 Chlorinated HLB April 2016 Finished Date November of presentation 9,

14 Results Halo-acetic acids (HAAs) found to be among the most abundant Br-DBPs, but some novel Br-DBPs were also detected with similar or even greater abundance The top 50 Br-DBPs contributed to 35.6% of total abundance (mass of OBr s)

15 Results Predicted structures for 41/50 most abundant Br- DBPs Of these 41 Br-DBPs, 18 were found to be aromatic acids or phenols 7 high-abundance heteroatomic Br-DBPs containing nitrogen or sulfur were detected

16 Sulfonic Acids Ethyl methanesulfonate

17 Conclusions 1)Established a library of ~700 Br-DBPs; most of these Br-DBPs have not been previously reported in drinking water 2)The method showed good precision on actual drinking water samples, by use of HLB-pH 2 3)Novel heteroatomic DBPs showed unexpectedly high abundance

18 Future Work Compare profiles of Br-DBPs at each stage of treatment Effects-directed analysis to identify most toxic fractions Fractionate chlorinated and source water extracts Cytotoxicity and comet assay MS analysis Extend method to a water treatment plant that employs a different treatment process (Prince Albert, SK)

19 Thank you Dr. Hui Peng Dr. Paul D. Jones Dr. John P. Giesy Les Dickson Dr. Lynn Weber

20 References Jeong, C. H.; Wagner, E. D.; Siebert, V. R.; Anduri, S.; Richardson, S. D.; Daiber, E. J.; McKague, A. B.; Kogevinas, M.; Villanueva, C. M.; Goslan, E. H.; Luo, W. T.; Isabelle, L. M.; Pankow, J. F.; Grazuleviciene, R.; Cordier, S.; Edwards, S. C.; Righi, E.; Nieuwenhuijsen, M. J.; Plewa, M. J., Occurrence and toxicity of disinfection byproducts in European drinking waters in relation with the HIWATE epidemiology study. Environ. Sci. Technol. 2012, 46 (21), Plewa, M. J.; Muellner, M. G.; Richardson, S. D.; Fasanot, F.; Buettner, K. M.; Woo, Y. T.; McKague, A. B.; Wagner, E. D., Occurrence, synthesis, and mammalian cell cytotoxicity and genotoxicity of haloacetamides: An emerging class of nitrogenous drinking water disinfection byproducts. Environ. Sci. Technol. 2008, 42 (3), Richardson, S. D., Environmental mass spectrometry: emerging contaminants and current issues. Anal. Chem. 2012, 84 (2), Richardson, S. D.; Plewa, M. J.; Wagner, E. D.; Schoeny, R.; DeMarini, D. M., Occurrence, genotoxicity, and carcinogenicity of regulated and emerging disinfection by-products in drinking water: A review and roadmap for research. Mutat. Res.-Rev. Mutat. Res. 2007, 636 (1-3),