Abstract:Residents of the Bayingnormen region of Inner Mongolia have been exposed to arsenic-contaminated well water for over 20 years, but relatively few studies have investigated health effects in this region. We surveyed one village to document exposure to arsenic and assess the prevalence of arsenic-associated skin lesions and self-reported morbidity. Five-percent (632) of the 12,334 residents surveyed had skin lesions characteristics of arsenic exposure. Skin lesions were strongly associated with well water arsenic and there was an elevated prevalence among residents with water arsenic exposures as low as 5 μg/L-10 μg/L. The presence of skin lesions was also associated with selfreported cardiovascular disease.

To understand the etiological burden of disease associated with acute health symptoms [e.g. gastrointestinal (GI), respiratory, dermatological], it is important to understand how common exposures influence these symptoms. Exposures to familiar and unfamiliar animals can result in a variety of health symptoms related to infection, irritation and allergy; however, few studies have examined this association in a large-scale cohort setting. Cross-sectional data collected from 50 507 participants in the United States enrolled from 2003 to 2009 were used to examine associations between animal contact and acute health symptoms during a 10-12 day period. Fixed-effects multivariable logistic regression estimated adjusted odds ratios (AORs) and 95% confident intervals (CI) for associations between animal exposures and outcomes of GI illness, respiratory illness and skin/eye symptoms. Two-thirds of the study population (63.2%) reported direct contact with animals, of which 7.7% had contact with at least one unfamiliar animal. Participants exposed to unfamiliar animals had significantly higher odds of self-reporting all three acute health symptoms, when compared to non-animal-exposed participants (GI: AOR = 1.4, CI = 1.2-1.7; respiratory: AOR = 1.5, CI = 1.2-1.8; and skin/eye: AOR = 1.9, CI = 1.6-2.3), as well as when compared to participants who only had contact with familiar animals. Specific contact with dogs, cats or pet birds was also significantly associated with at least one acute health symptom; AORs ranged from 1.1 to 1.5, when compared to participants not exposed to each animal. These results indicate that contact with animals, especially unfamiliar animals, was significantly associated with GI, respiratory and skin/eye symptoms. Such associations could be attributable to zoonotic infections and allergic reactions. Etiological models for acute health symptoms should consider contact with companion animals, particularly exposure to unfamiliar animals. Prevention of pet-associated zoonotic diseases includes commonsense measures such as hand-washing, but are often overlooked by pet owners and non-pet owners alike.