Hidden poison; MTBE tainting water across state.(Main)

Byline: MATT PACENZA STAFF WRITER

More than two years after New York banned the gasoline additive MTBE, hundreds of public drinking wells across the state remain tainted with the toxic chemical.

Worse, neither state nor local government has any reliable information about how many private wells are at risk, although 1.3 million New Yorkers get their water from private wells. Even though it's gone from gasoline, methyl tertiary butyl ether - still unknown to many New Yorkers - has quietly become the state's single largest water pollution problem and a public health threat expected to linger for years.

The bitter irony is clear: MTBE was put in our gasoline to make our air cleaner, but it is poisoning our water.

A four-month investigation by the Times Union found that state authorities have frequently reacted slowly and have failed to protect the public from MTBE spills. Worst of all, many residents who live near leaking storage tanks, sources of most of the MTBE that enters the environment, say they were never told they might have a problem - or urged to have their wells tested.

MTBE has been found at levels above the state safety limit in 46 public water supplies since 2004, when New York first required tests for the chemical, according to state computer records. At least 172 water supplies were found to have at least some MTBE. Untold numbers of private wells across the state have dangerous levels of MTBE.

"MTBE is an issue from the end of Long Island to Buffalo," said Bill Cooke of the Citizens Campaign for the Environment. "All you have to do is look for it."

New York has been wrestling with the threat posed by MTBE for at least 15 years, ever since evidence grew that the gasoline additive moved swiftly into groundwater from sites like gas stations with underground storage tanks. Unlike other toxins found in gasoline, MTBE dissolves in water, doesn't cling to soil and persists for years underground - properties that make it a potent threat to groundwater.

The danger posed by the toxin could soon become much more worrisome: Federal officials have considered reclassifying MTBE as a "likely carcinogen," a move that would put it in the same category as potent poisons like DDT and benzene. The toxin is currently considered only a "potential carcinogen," based on research that showed mice and rats develop higher rates of certain cancers after ingesting it.

A16 Possible links to cancer.

Most experts say there has not been enough research about MTBE to determine how dangerous it is. One exception is Mobil's former worldwide director of environmental health, Myron Mehlman.

"MTBE causes cancer," said Mehlman, a retired toxicologist. "Most regulatory bodies have totally miscalculated what the threat levels should be."

Since the MTBE problem was first discovered, staff from the state Department of Environmental Conservation have …