RESUMO
ObjectiveA method was developed for the rapid determination of 18 common disinfection by-products including halogenated oxides and haloacetic acid （HAAs） in drinking water by high performance liquid chromatography tandem mass spectrometry （HPLC-MS/MS）. MethodThe water sample was filtered by 0.22 μm hydrophilic membrane then the analytes were separated on a PFP （2.1 mm× 100 mm， 2.7 μm） pentafluorophenyl column with 0.1% acetic acid and acetonitrile as mobile phase gradient elution. Ionization in anionic electrospray mode was detected by multi-reaction monitoring （MRM） mode. The external standard method was used for quantitation. ResultsThe correlation coefficients of 18 disinfection by-products were above 0.999 in the corresponding linear range. The average spiked recoveries of 1， 10 and20 times of LOQ of each analyte were 91.6%‒101.8%， and the relative standard deviation （RSD） was 1.2%‒6.4%. The LOD and LOQ were 0.020‒2 μg·L-1 and 0.050‒5 μg·L-1， respectively. ConclusionThis method is simple， sensitive and accurate， and could be used for the routine analysis of 18 common disinfection by-products in drinking water.
RESUMO
ObjectiveTo explore the variation rules and health risks of trihalomethane in regional drinking water， and to provide evidence for the innovative water processing technology and the optimization of drinking water quality. MethodsBased on regional drinking water sanitation monitoring， non-parametric rank sum test was used to analyze the effects of residual trihalomethane production in different periods and with disinfection methods. The United States environmental protection agency （USEPA） classic "four-step" health risk assessment model was used to evaluate the carcinogenic risk and non-carcinogenic risk of trihalomethane through drinking water exposure. ResultsThe yield of trichloromethane in wet season was 6.3 μg·L-1， which was higher than that in dry season. Compared with chlorination pretreatment， ozone pretreatment reduced the content of bromomethane dichloromethane. Compared to liquid chlorine disinfection， sodium hypochlorite treatment incresed the levels of trichloromethane and bromomethane chloride. Although the total carcinogenic and non-carcinogenic risks of trihalomethane in drinking water in the region were at safe levels， they were above the acceptable limits occasionally. The highest carcinogenic risk of trihalomethane were dichlorobromomethane and chlorodibromomethane，and the highest non-carcinogenic risk was trichloromethane. The health risk of children was 1.2 times higher than that for adults. ConclusionThe production of residual trihalomethane in drinking water in this area is relatively low， which is less harmful to the health of adults and children. Monitoring， including other disinfection byproducts， should continue and appropriate disinfection techniques for drinking water should be explored.