Taiwan: Environmental Health Concerns

Abstract

Cross-sectional surveys and follow-up studies carried out in southwestern and northeastern Taiwan have first identified several health hazards induced by long-term exposure to arsenic in drinking water. Arsenic in drinking water is associated with an increased risk of skin and internal cancers, peripheral vascular disease, ischemic heart disease, cerebral infarction, carotid atherosclerosis, electrocardiographic abnormalities (prolongation and increased dispersion of heart rate-corrected QT wave), microcirculation anomaly, diabetes mellitus, hypertension, posterior subcapsular opacity, pterygium, neurobehavioral (pattern memory and switching attention) disorders, peripheral neuropathy, erectile dysfunction, hepatitis and cirrhosis, kidney disease, and fungal infection of hands and feet in a dose–response relation. Genetic or acquired susceptibility play an important role in the arsenic-induced health hazards. Many molecular and genomic biomarkers have been developed to explore the gene–environment interactions in the pathogenesis of arsenic-induced health hazards. In the analysis of cancer mortality data of residents living in the Blackfoot disease-endemic area in southwestern Taiwan, the original standard of arsenic in drinking water (50ppb) is associated with a substantial risk of cancer and is not sufficiently protective of public health. The findings have been used to set up the maximal contamination level of arsenic in drinking water (10ppb), which was adopted by the World Health Organization, US Environmental Protection Agency, and many countries.