Study On Relationship Between Arsenic Exposure And Health Effects In Inner Mongolia

Objective To study the health effects of residents exposed to arsenic in drinking water and their dose-effects relationship, to analyse the relationship of influence factors of health effects, to assess the health risk of arsenic exposure. Methods To analyse by retrospective cohort study. A cluster and stratified sampling method were used to select area and subjects according to arsenic concentration in drinking water. The subjects were asked to resident more than 8 years. They were divided into four groups according to arsenic level: control(<10μg/L), low(10-100μg/L), medium(101-200μg/L) and high(>200μg/L). Results 1.The level of skin lesion aggravated with increasing of the arsenic concentration in drinking water. The prevalence of keratosis and abnormal skin pigmentation in control, low, medium and high group were 18.4%, 21.1%, 25.9%, 38.6% and 1.5%, 2.2%, 5.6%, 17.8%. There were significant differences for clinical type among four groups of As exposed subjects(P<0.01). The number of patients increased and their conditions became more serious with the arsenic level increasing. The results showed a dose-effect relationship. 2.The multivariate factor analysis showed that the risk factors of keratosis were age, pesticide and the arsenic content in drinking water(OR=1.387, 1.583, 1.321, P<0.05), while occupation and vitamin were it’s protective factors(OR=0.307,0.260, P<0.05). The risk factors of abnormal skin pigmentation were age, pesticide, the content of nail arsenic, fluorosis and the arsenic content in drinking water(OR=1.724, 2.636, 2.741, 3.699, 1.863, P<0.05), while sex was it’s protective factor(OR=0.255, P<0.01). 3. The water As content was positively associated with nail As content (r=0.896, P<0.01), but was inversely associated with nail Se content (r=-0.322, P<0.01). The nail As content was also negatively associated with nail Se content (r =-0.355, P<0.01). The nail As was positively associated with clinical type of subjects exposed to arsenic (r =0.225, P<0.01). 4. To contrast with control group, the HbA1c level of high group increased(P<0.05). 5. With the increasing of arsenic concentration in drinking water, the prevalence of Coronary Heart Disease, hypertension and nervous system increased. The results indicated a dose-effect relationship too. Conclusion Many system of person could be damaged when exposed to chronic arsenic. The damage degree was associated with lots of factors except arsenic. A integrated measures should be implemented to prevent arsenism and long-term effects.