Association between ingested arsenic and cataracts

An eye examination was added in the 1996 followup of the blackfoot-disease-endemic cohort of southwestern Taiwan to study whether long-term exposure to inorganic arsenic has any effect on various types of cataracts. The Lens Opacities System III was used to classify different types of cataracts. Cumulative arsenic exposure was derived from the history of consuming artesian well water from the 1988 baseline interview, and the arsenic level of the well water from two government surveys. A total of 349 participants were involved in the study. Posterior subcapsular (PSC) opacities were seen in 22% of the study subjects, higher than in most previous reports. Cumulative arsenic exposure had a dose–response relationship with prevalence of PSC (p = 0.014), after adjustment for age, sex, DM status and sunlight exposure. A large study is needed to confirm the present finding, or an animal study will be helpful in elucidating the mechanism of inorganic arsenic effect on cataracts.