An analysis of monitoring results of drinking water type endemic arsenic poisoning in Qinghai Province from 2010 to 2013

Objective To observe the illness change trend of drinking water type endemic arsenic poisoning in Qinghai Province, comprehensively evaluate the effect of prevention and control measures, in order to provide a scientific basis for timely adjustment of the prevention and control measures. Methods From 2010 to 2013, according to the "Drinking Water Type Endemic Arsenic Poisoning Monitoring Programs", 3 villages in 2 counties within Qinghai Province were randomly selected as monitoring sites. The arsenic content in drinking water of residents was measured, water improvement projects in all monitoring villages were investigated; at the same time an investigation of arsenic disease in resident population was conducted, and urinary arsenic content was monitored. Arsenic in drinking water and urine was determined by hydride generation atomic fluorescence spectrometry, and arsenic poisoning was diagnosed using "Endemic Arsenic Poisoning Diagnostic Criteria" (WS/T 211-2001). Results Of the three water improvement projects, two were water arsenic exceeded the standard, and one was intermittently operated. From 2010 to 2013, the arsenic poisoning detection rate in Baoning Village was 27.30% (193/707), 31.90% (245/768), 29.35% (221/753) and 28.22% (219/776); in Kecai Village was 32.62% (107/328), 34.83% (124/356), 31.26% (131/419) and 29.35% (118/402); and in Manimotai Village was 56.58% (43/76), 52.81% (47/89), 45.10% (46/102) and 34.69% (34/98), there was no significant difference statistically of the arsenic poisoning detection rates in the three monitored villages in the 4 years (χ2 = 3.09, 0.04, 0.92, all P > 0.05). From 2010 to 2013, women arsenic poisoning detection rate was 36.45% (203/557), 40.59% (246/606), 36.12% (225/623) and 34.77% (218/627), respectively; men was 25.27% (140/554), 28.01% (170/607), 26.57% (173/651) and 23.57% (153/649), respectively; women arsenic poisoning detection rates were higher than those of men (χ2 = 16.25, 21.32, 13.49, 19.38, all P < 0.05). Arsenic poisoning detection rate of people younger than 60 years old had a tendency to increase with age. In 2012 and 2013, 105 and 93 urine samples were tested, respectively; urinary arsenic geometric mean was 0.113 and 0.149 mg/L. Conclusions Water improvement projects and water quality are not optimistic, and prevalence of arsenic poisoning is still at a higher level. A sound long-term monitoring program should be established as soon as possible, the management and maintenance of water improvement projects should be strengthened, and the monitoring and prevention work should not be neglected. Key words: Arsenic poisoning; Population surveillance; Drinking water; Urine