Interactions of chloramine with organic nitrogen compounds during purification of water for drinking may generate carcinogenic N-nitrosodime-thylamine (NDMA) as byproduct, and it has been found that cationic amine-based water treatment polymers may be one of the important precursors of NDMA. We have analyzed experimentally the influence rule of NDMA formation during chlorination and disinfection, in order to provide technical support for reducing or even avoiding the formation of NDMA. The formation characteristics of nitrosamines during the chlorination of poly-diallyldimethylammonium chloride (polyDADMAC) have been studied during our experiments. The results show that the type of chlorinating agent is crucial for the generation of NDMA; if pH = 7, NDMA has the great potential formation; the NDMA potential formation increases with temperature. The yield of NDMA will be higher as the concentration of monochloramine is 1.5 to 2.5 times of the precursor; the variation of polymer with reaction time can explain the concentration of NDMA in terminal water of pipe network is higher than that in drinking water.
References
[1]
Dong, L., Wang, H.Y., Cai, H.q., et al. (2016) Investigation of Status Quo of Nitrogenous Disinfection By-Products in Drinking Water in Six Cities of China. Chinese Journal of Environment and Health, 33, 232-235.
[2]
Cal, D. (2011) NDMA and Other Nitrosamines-Drinking Water Issues.
[3]
Mitch, W.A. and Sedlak, D.L. (2002) Formation of N-Nitrosodimethylamine (NDMA) from Dimethylamine during Chlorination. Environmental Science & Technology, 36, 588-595. https://doi.org/10.1021/es010684q
[4]
Shah, A.D. and Mitch, W.A. (2011) Halonitroalkanes, Halonitriles, Haloamides, and N-Nitrosamines: A Critical Review of Nitrogenous Disinfection Byproduct Formation Pathways. Environmental Science & Technology, 46, 119-131. https://doi.org/10.1021/es203312s
[5]
Bond, T., Templeton, M.R. and Graham, N. (2012) Precursors of Nitrogenous Disinfection By-Products in Drinking Water: A Critical Review and Analysis. Journal of Hazardous Materials, 235-236, 1-16. https://doi.org/10.1016/j.jhazmat.2012.07.017
[6]
Park, S.H., Wei, S., Mizaikoff, B., et al. (2009) Degradation of Amine-Based Water Treatment Polymers during Chloramination as N-Nitrosodimethylamine (NDMA) Precursors. Environmental Science & Technology, 43, 1360-1366. https://doi.org/10.1021/es802732z
[7]
Padhye, L., Luzinova, Y., Cho, M., et al. (2011) PolyDADMAC and Dimethylamine as Precursors of N-Nitrosodimethylamine during Ozonation: Reaction Kinetics and Mechanisms. Environmental Science & Technology, 45, 4353-4359. https://doi.org/10.1021/es104255e
[8]
Munch, J.W. and Bassett, M.V. (2004) Method 521, Determination of Nitrosamines in Drinking Water by Solid Phase Extraction and Capillary Column Gas Chromatography with Large Volume Injection and Chemical Ionization Tandem Mass Spectrometry (MS/MS). National Exposure Research Laboratory Office of Research and Development, US Environmental Protection Agency, Cincinnati.
[9]
Chen, W., Li, X., Huang, H., et al. (2013) Comparison of Gas Chromatography-Mass Spectrometry and Gas Chromatography-Tandem Mass Spectrometry with Electron Ionization for Determination of N-Nitrosamines in Environmental Water. Chinese Journal of Spectroscopy Laboratory, 168, 1400-1410. https://doi.org/10.1016/j.chemosphere.2016.11.109
[10]
Shen, R. and Andrews, S.A. (2013) Formation of NDMA from Ranitidine and Sumatriptan: The Role of pH. Water Research, 47, 802-810. https://doi.org/10.1016/j.watres.2012.11.004