(Updates with details on spill, including number affected)
Jan 9 (Reuters) - About 100,000 homes and businesses in West Virginia were being told on Thursday not to use tap water for drinking, cooking or bathing following a chemical spill along the Elk River in Charleston, the state's capital, according to local officials.
Governor Earl Ray Tomblin declared a state of emergency for five counties as a result of the spill of 4-Methylcyclohexane Methanol, a chemical used in the coal industry.
Health officials were advising residents only to use the water for flushing and fire fighting.
The spill originated with Freedom Industries, a Charleston company, according to Laura Jordan, external affairs manageer for West Virginia American Water.
It occurred right above the intake of the Kanawha Valley water treatment plant in Charleston -- the largest in West Virginia -- and affects 100,000 customers, or 250,000 to 300,000 people, Jordan said.
"It could be potentially harmful if swallowed and could potentially cause skin and eye irritation," Jordan said. She did not know the exact time of the spill.
Jordan said the water company and state environmental officials were doing tests on the water. She said she did not know when the use ban would be lifted.
The company is working with state and federal authorities to get residents access to bottled water, and water distribution sites will be announced through local media, Jordan said.
"We're pooling our resources and determining the areas that need it first, like hospitals," she said.
A representative for Freedom Industries was not immediately available for comment. (Reporting by Mary Wisniewski; Editing by Andre Grenon and Leslie Adler)