Is Your Water Safe? Arsenic and Heart Risks

Long-term exposure to arsenic in drinking water has been linked to an increased risk of cardiovascular diseases, particularly heart disease, even at levels below the federal limit of 10µg/L, according to a study from Columbia University Mailman School of Public Health. This research is the first to outline exposure-response relationships at concentrations under the regulatory threshold, confirming that ongoing exposure contributes to ischemic heart disease.

The study highlighted that arsenic exposure in the past decade prior to a cardiovascular event posed the highest risk. Published in Environmental Health Perspectives, the findings were presented by Danielle Medgyesi, who emphasized the importance of considering non-cancer outcomes, particularly given the significant role of cardiovascular disease in global mortality.

The research utilized health care records from the California Teachers Study cohort covering 1995 to 2018. The analysis included 98,250 participants, identifying over 6,100 cases of ischemic heart disease. Collaborating with the California Office of Environmental Health Hazard Assessment (OEHHA), the team gathered three decades of water arsenic data.

The results showed that nearly half of participants had arsenic concentrations below California's non-cancer health goal of <1 µg/L. Compared to this group, those with exposures of 1 to <5 µg/L had a 5–6% increased risk, while the risk jumped to 20% for levels of 5 to <10 µg/L, and 42% for those at or above the current EPA limit of ≥10µg/L.

The study consistently found stronger associations with ischemic heart disease rather than broader cardiovascular issues, aligning with previous research that highlighted significant risks at higher levels. This underscores the health implications for communities with arsenic levels exceeding the EPA standards.

Additionally, the findings revealed that higher arsenic concentrations disproportionately affect Hispanic and Latina populations, as well as residents in lower socioeconomic neighborhoods. Tiffany Sanchez, a senior author at Columbia Mailman, called for a renewed discussion on current policies and regulatory standards.

The study emphasizes the urgent need for updated regulatory standards to protect public health and suggests that further research is essential to understand the health risks associated with arsenic levels currently experienced by community water system users.