云南省一起慢性砷中毒的流行病学调查

Epidemiological investigation of a case of chronic arsenic poisoning in Yunnan Province

目的对云南家族性砷中毒人群进行砷中毒流行病学调查，发现砷中毒来源，建立典型病例档案，以提高对地方性砷中毒的认识，为地方性砷中毒防治工作提供科学依据。方法2013年，在云南省下小营村，以发现的砷中毒患者家族内全部成员为调查对象，进行健康体检与砷中毒流行病学调查．建立砷中毒患者家族谱和个人档案。采集调查对象饮用水样、发样、尿样进行砷含量测定；采集血样进行生化检测；对过度角化溃烂皮肤进行病理切片检查。结果共调查家族成员33人，砷暴露15人，非砷暴露18人。砷暴露的15人均有皮肤损伤，其中最年长的2位男性，分别于1994和2009年死于皮肤癌和脑出血。砷暴露的15人（1935-1983年出生）在1973-1989年，曾饮用过被含砷农药污染的井水5～16年不等。截至2013年，已停止砷暴露24年，但被污染水井水砷含量仍为0．624mg／L，是世界卫生组织推荐最高限值（0．01mg／L）的62-4倍。砷暴露人群和非砷暴露人群头发和尿无机砷含量中位数分别为4．2、3．7mg／kg，60．9、41．0μg／L，发砷比较差异无统计学意义（Z=-1．905，P〉0．05），尿砷比较差异有统计学意义（z=-3．002，P〈0．05）。砷暴露人群和非砷暴露人群血清天门冬氨酸氨基转移酶（AST）、γ-谷氨酰基转移酶（γ-GT）、24h尿肌酐（Cr）含量中位数分别为37．5、31．0U／L，25．5、12．0U／L，13834．0、6843．0μmol／L，两组比较差异有统计学意义（Z=-2．776、-2．311、-2．502，P均〈0．05）。12例砷暴露者进行了健康体检及流行病学调查，均表现为典型的皮肤三联征，其中中度患者2例、重度患者10例。病理检查结果显示，8例为基底细胞癌和（或）鳞状上皮细胞癌。结论饮用含砷农药污染水源可致人群慢性砷中毒，停止砷暴露后对机体的损害依然严重，显示出作用的远期效应，应予以关注。

Objective To conduct an epidemiological investigation on a case of familial arsenic poisoning in Yunnan Province, to find arsenic poisoning source and create a archive of typical cases, in order to raise awareness of endemic arsenicosis and provide scientific materials for prevention and treatment of the disease. Methods In Xiaxiaoying Village of Yunnan Province, all members of a family with arsenic poisoning patients were investigated in 2013, their health examination and epidemiological survey of arsenic poisoning were carried out, and arsenic poisoning family profiles and personal files were established. Drinking water, hair and urine samples were collected for arsenic content determination, blood samples were collected for biochemical detection, excessively keratose skin was collected for pathological biopsy. Results A total of 33 family members were investigated.Among them 15 were exposed to arsenic and 18 were not exposed to arsenic. Fifteen people exposed to arsenic were found to be have skin lesions, and two eldest males died of skin cancer and cerebral hemorrhage in 1994 and 2009, respectively. The survey found out that 15 patients born in 1935 - 1983 had been drinking arsenic pesticides polluted well water for 5 to 16 years from 1973 to 1989. As of 2013, the arsenic exposure had been stopped for 24 years, the content of arsenic in the polluted wells was 0.624 mg/L, which was 62.4 times the recommended maximum limit （0.01 mg/L） of the World Health Organization. The median of hair and urinary arsenic in arsenic exposed population and non-arsenic exposed population was 4.2, 3.7 mg/kg and 60.9, 41.0 μg/L, respectively. There was no statistically significant difference in hair arsenic （Z = - 1.905, P 〉 0.05）, but the difference of urinary arsenic was statistically significant （Z = - 3.002, P 〈 0.05）. The median of aspartate aminotransferase （AST）, gamma- glutamyltransferase （γ-GT） and 24 hours urinary ereatinine （Cr） in arsenic exposed population and non-arsenic exposed population was 37.5, 31.0 U/L, 25.5, 12.0 U/L, 13 834.0, and 6 843.0 μmo]/L, respectively. The differences between the two groups were statistically significant （Z = - 2.776, - 2.311, - 2.502, P 〈 0.05）. Twelve cases of arsenic poisoned patients who were conducted health examination and epidemiological investigation showed typical triad of skin, among them 2 cases were moderate and 10 cases were severe. Pathological biopsy results showed 8 cases had basal cell carcinoma or squamous cell carcinoma. Conchmions Drinking arsenical pesticide contaminated water can induce chronic arsenic poisoning, even after the cessation of arsenic exposure. We should pay close attention to its long-term serious harmful effect.