A West Virginia state official told a legislative panel on Wednesday that he ‘can guarantee” residents are breathing in formaldehyde, a known carcinogen, nearly three weeks after a massive chemical spill contaminated the water supply for more than 300,000 residents.

Scott Simonton, a Marshall University environmental scientist and member of the state Environmental Quality Board, told the panel that he had found formaldehyde in local water samples and was alarmed by the lack of information regarding the lingering impacts of the spill on public health, the Charleston Gazette reported.

‘It’s frightening, it really is frightening,” Simonton said. ‘What we know scares us, and we know there’s a lot more we don’t know.”

On January 9, Freedom Industries reported a leak of crude MCHM, a mixture of chemicals used in the coal production process, from its storage facility on the Elk River and into the water supply for 16 percent of the state’s population. Simonton said the crude MCHM can be broken down into formaldehyde, which causes cancer, and inhaled while people are showering.

Very little is known about crude MCHM and just how toxic it may be to humans. Initially, state authorities maintained that levels of the chemicals below 1 part per million were […]