A new twenty-year study published in JAMA Network has shown that lower levels of arsenic in drinking water are associated with lower rates of death from heart disease and cancer.
The study included a prospective cohort of over 10,000 adults in Bangladesh. Participants were enrolled in the study between 2000 and 2002, and their well water arsenic levels were measured at this time. Urinary arsenic levels were measured up to five times per participant through 2018, and mortality among the participants was tracked through 2022. In general, arsenic levels in well water supplies declined throughout the study due to mitigation efforts. High arsenic levels in drinking water have previously been linked to a higher risk of chronic diseases such as heart disease and cancer, and this study sought to determine whether reduced arsenic exposure over time led to a decreased risk of mortality due to chronic diseases.
The results showed that reductions in arsenic levels in drinking water led to significant decreases in mortality due to several chronic diseases, including heart disease and cancer. Each interquartile range decrease in urinary arsenic observed in the participants was linked to a 22% lower risk of mortality due to any chronic disease, a 20% lower risk of cancer mortality, and a 23% lower risk of cardiovascular disease mortality. Greater decreases in arsenic levels were associated with greater reductions in risk. Encouragingly, people whose arsenic levels fell from high to low during the course of the study had chronic disease risk that was comparable to the risk of people with consistently low exposure throughout the study.
The authors of the study noted that lowering arsenic levels in drinking water sharply reduced deaths from cancer and heart disease during their study. These results may help policymakers around the world advocate for cleaner drinking water.
Sources: JAMA Network, Science Daily