Federal study of MCHM concludes

A just-released federal study of 4-methylcyclohexanemethanol (MCHM) concluded that exposure to the chemical after it spilled into the Elk River in Charleston, W. Va., in January 2014 is “not likely to be associated with any adverse health effects.”

MCHM was the largest component of a mixture of chemicals that leaked from a corroded commercial storage tank upstream of the water supply for some 300,000 people. At the time of the spill, little was known about MCHM, an alicyclic alcohol used to process coal.

City officials issued a ban on the use of tap water for drinking and washing that lasted more than a week for some of the affected residents. Some reported skin irritation and stomach upset from exposure to contaminated water.

Lack of information about MCHM and other components of the spilled liquid led the Centers for Disease Control & Prevention to request further study from the National Toxicology Program (NTP), a federal program that investigates chemicals of concern to public health.

“Alicyclic alcohols and other chemicals of this sort are likely to have similar toxicological properties,” says Scott S. Auerbach, a molecular toxicologist who worked on the study. Still, the toxicology of many chemicals in the class, including MCHM, was unknown prior to the year-long study, he says.

NTP identified MCHM as a developmental toxicant at concentrations “considerably higher” than the drinking water limit set by CDC after the spill. In its final report, NTP confirmed that the limit instituted by CDC was adequate and that exposure at or below that level is not likely to pose health effects.

A separate analysis by the West Virginia Department of Health & Human Resources found no significant change in birth weight for babies born before and after the spill.