In January 2014, approximately 10,000 gallons of chemicals used to process coal spilled from a storage tank into the Elk River in West Virginia. The Elk River is a municipal water source that serves about 300,000 people in the Charleston area. In July 2014, the National Toxicology Program received a nomination from the Centers for Disease Control and Prevention/Agency for Toxic Substances and Disease Registry to conduct toxicity studies on the main chemicals known to be involved in the spill. The primary spilled agent was 4-methylcyclohexanemethanol (MCHM). Other chemicals were also present in lower amounts in the tank. Limited data were available to address concerns for potential human health effects for the compounds in the spilled liquid, so NTP completed a series of toxicity studies on these chemicals. For more information, visit the NTP West Virginia Chemical Spill webpage.