Trihalomethanes The results of a cohort study published in JAMA Network Open show the effect of trihalomethanes in community drinking water on the risk of chronic kidney disease (CKD). Trihalomethanes (THMs) are one of several unintended byproducts of chlorination, and include chloroform and three brominated compounds (bromodichloromethane, dibromochloromethane, and bromoform), with the latter more common in coastal and saltwater regions. Exposure to THMs has already been established as a r...