Long-term exposure to arsenic in drinking water may increase the risk of cardiovascular disease even at exposure levels below the regulatory limit, according to a new study on Wednesday. 

The study led by researchers at Columbia University in the US is the first to describe exposure-response relationships at concentrations below the current regulatory limit (10 micrograms per litre). It also substantiates that prolonged exposure to arsenic in water contributes to the development of ischemic heart disease.