Experimental study on N-nitrosamine disinfection by-products produced by four pharmaceuticals and personal care products during chlorination disinfection
Objective To investigate the effect of pharmaceuticals and personal care products(PPCPs)on the formation potential of the nitrogen-containing disinfection by-products N-nitrosamines(NAs)after entering the water environment and being oxidized by chlorination.Methods Four commonly used pharmaceuticals,i.e.,ranitidine,nizatidine,chlorpheniramine,and doxylamine,were selected as precursors,and sodium hypochlorite,monochloramine,and dichloramine were used as disinfectants to simulate the chlorin-ation procedure in water treatment process.The formation potential of eight NAs was analyzed,namely N-nitrosodimethylamine(ND-MA),N-nitrosodiethylamine(NDEA),N-nitrosomethylethylamine(NMEA),N-nitrosodi-n-propylamine,N-nitrosodi-n-butylamine(NDBA),N-nitrosomorpholine(NMOR),N-nitrosopiperidine(NPIP),and N-nitrosopyrrolidine.Results NDMA was the main sub-stance produced by the four pharmaceuticals during chlorination disinfection,accompanied by the production of NMEA,NDEA,NMOR,and NPIP,and NDMA showed the highest formation potential after monochloramine disinfection.Ranitidine showed the high-est formation potential of NDMA potential regardless of sodium hypochlorite disinfection or chloramine disinfection.Ranitidine could al-so produce NPIP after oxidation with sodium hypochlorite,and it became a precursor with relatively high formation potential of NAs due to its structural characteristics.Conclusion All four PPCPs are precursors for the production of NAs during chlorination disinfection,and controlling the emission of PPCPs into the environment at source or optimizing the disinfection process can effectively control the production of NAs.
pharmaceuticals and personal care productschlorination disinfection processnitrogen-containing disinfection by-productsN-nitrosamine formation potentialmolar conversion rate
万方数据
维普
