Content analysis and health risk assessment of arsenic and chloroform in municipal water of Guangyuan City from 2019 to 2022
Objective To analyze the content and distribution of arsenic and chloroform in municipal water of Guangyuan City after the introduction of Bailong river as the source water,and to evaluate the health risks caused by them.Methods The monitoring data of arsenic and chloroform in 1 789 water samples from Guangyuan City from 2019 to 2022 were collected and analyzed the levels of arsenic and chloroform in different types,different water periods and different regions,and the health risk model which recommended by the US Environmental Protection Agency was used to assess the health risk to the population through drinking water routes.Kruskal-Wallis rank sum test was used to compare the data of multiple groups of water samples,and Mann-Whitney U test was used to compare the data of two groups of water samples,with the test level α=0.05.Results The contents(median)of arsenic and chloroform in 1 789 water samples were 0.000 70 mg/L and 0.005 42 mg/L pass rates were 99.94％and 99.72％,respectivley.Carcinogenic risk was 2.93×10-5 and 4.69×10-6,non-carcinogenic risk was 0.065 2 and 0.015 1.In different types of water samples,the contents of arsenic and trichloromethane were in the order of secondary water supply＞tap water＞finished water.The arsenic and chloroform contents in water samples of different water periods were in the order of wet season＞level season＞dry season.In the water samples from different regions,the content of arsenic content was in the order of Chaotian District＞Lizhou District＞Zhaohua District,and those of chloroform content was Lizhou District＞Chaotian District＞Zhaohua District.Conclusions The carcinogenic risks of arsenic and chloroform in municipal water of Guangyuan city from 2019 to 2022 both exceed the low risk level recommended by the US Environmental Protection Agency and that should be closely monitored.The contents of arsenic and chloroform in secondary water supply were higher than those in finished water and tap water,so the management should be strengthened.The Bailong river had little effect on the arsenic and chloroform in municipal water of Guangyuan city.However,the difference of arsenic and chloroform in the water samples of Lizhou district,Zhaohua district and Chaotian district was statistically significant,and the water sources were all surface water,which should be continuously monitored and evaluated.
municipal waterarsenicchloroformhealth risk assessment
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NSTL
万方数据
