To assess the health effects of arsenic poisoning and to determine the relationship among duration and severity of skin lesions, exposure dose of arsenic, and nutritional status of people, 150 patients attending the Dermatology Outpatients Department of Sher-e-Bangla Medical College Hospital, Barisal, Bangladesh, were included in this cross-sectional study. The study was conducted during January-December 2000. Records of patients were collected prospectively using a pre-tested questionnaire, which included information on demography, sources of water for drinking and cooking, duration and amount of drinking-water obtained from shallow tubewells, clinical presentations, complications, and physical and laboratory findings. Water samples from tubewells currently being used by individual patients were examined. Nine percent of the patients were unaware that arsenic-contaminated water causes diseases. Due to lack of alternative water supplies, 25% of the subjects were still drinking water from contaminated tubewells. About 18% did not complain of any clinical symptoms, except that their skin lesions were ugly-looking, and 82% had moderate or severe skin lesions. Thirty-one percent of the water samples had arsenic concentrations 10-fold higher than the permissible limit of 0.05 mg/L in Bangladesh and 50-fold higher than the WHO guideline value of 0.01 mg/L. The mean arsenic concentration in water was significantly associated with the severity of disease. Body mass index correlated inversely (r = -0.298, p = 0.013) with the duration of disease after controlling for age. The findings suggest the need to enhance public awareness on negative health effects of arsenic poisoning in rural Bangladesh. From a public-health perspective, effective intervention strategies need to be developed to curb the exposure, strengthen rapid diagnostic facilities, establish effective treatment facilities in rural areas, and improve the nutritional status of people.