Sanitary inspection results of drinking water quality in stations along Hexi Corridor Railway in 2018 -2020 / 公共卫生与预防医学

ABSTRACT

Objective To understand the sanitary status of drinking water quality in stations along Hexi Corridor Railway from 2018 to 2020. Methods Among of 270 samples of drinking water collected by a railway CDC from 2018 to 2020 were detected and analyzed. Results A total of 270 water samples were detected from 2018 to 2020. Among them, 90 water samples were detected in train water supply stations, and 89 were qualified, with a qualified rate of 98.89%. 180 water samples were detected in non-train water supply stations, and 119 samples were qualified, with a qualified rate of 66.11%. The qualified rate of water quality test items in train water supply stations was significantly higher than that in non-train water supply stations (χ2=36.44, P＜0.05). There was no significant difference in the qualified rate of water quality test items in different years (χ2=2.4,3.01, 0.04, P＞0.05). Conclusion The drinking water source of each station along the Hexi Corridor Railway is supplied by deep groundwater. Without adding disinfectant, the total bacterial count, coliform group, Escherichia coli and other indicators of drinking water in all stations meet GB5749-2006 “sanitary standard for drinking water”. This raises a question on the necessity to add disinfectant when deep groundwater is used as drinking water source. However, the train water supply station, which is used as the source of secondary water supply, provides drinking water for railway train passengers. The free residual chlorine in the water after chlorination can continuously kill microorganisms in the water. Therefore, it is necessary to add disinfectant to the source water of the train water supply station.