Federal officials aren't granting a state request for more animal tests for a chemical that spilled into West Virginia's largest drinking water supply in January.
In February, Gov. Earl Ray Tomblin asked for additional tests to determine the long-term health effects of consuming, breathing or coming in contact with the spilled chemical, crude MCHM.
In a March 13 letter made public Thursday, the Centers for Disease Control and Prevention told state health officials it believed long-term effects were unlikely. CDC described plans only to track trends with resources like birth defects surveillance, cancer registries and health systems data.