Complete Ban Of MTBE To
Be Sought By EPA
With Congress
By Matthew L. Wald

The Environmental Protection Agency will propose that Congress no longer require oil companies to add an ingredient to gasoline that is meant to make the air cleaner, because it pollutes water.
A panel appointed by the E.P.A. is set to report on Tuesday that use of the much-debated ingredient, M.T.B.E., a possible carcinogen, should be "reduced substantially" because it dissolves easily in water and turns up in tap water when gasoline has leaked or spilled.
Even before the report was made public, Carol M. Browner, the agency's administrator, said today that Americans should have "both cleaner air and cleaner water -- and never one at the expense of the other."
Ms. Browner, whose agency in the past has defended M.T.B.E. mandates to critics who said it posed health problems, said she would urge Congress to change rules passed in 1990 requiring oil companies to put an "oxygenate" in gasoline. Oxygenates, chemicals that incorporate an oxygen atom, promote more thorough burning in engines. Most oil companies chose the oxygenate known as M.T.B.E., for methyl tertiary butyl ether.
After Congress required an oxygenate in nine big metropolitan areas -- those with the dirtiest air, including New York, Hartford, Philadelphia, Chicago, Los Angeles and Houston -- other communities voluntarily embraced the use of M.T.B.E., which not only cuts carbon monoxide but dilutes toxic components like benzene and toluene.
Experts differ on how much the ingredient has done to control carbon monoxide and smog, but they agree that it has cut toxic components from gasoline in the air by about 30 percent.
But when fuel leaks from underground tanks or pipelines or is spilled, M.T.B.E. dissolves in water and flows into wells. And microbes in soil that digest natural hydrocarbons, making them harmless, do not care for M.T.B.E., experts say.
The draft of the panel's findings calls for Congress to drop the Federal requirement that gasoline sold in the big cities contain M.T.B.E., and that its use be "reduced substantially." A summary of the draft did not define substantial.
The draft has been widely circulated and its contents were confirmed today by the panel's chairman, Dan Greenbaum, who is also president of the Health Effects Institute, a nonprofit group financed by the environmental agency and the auto industry.
In a telephone interview, Greenbaum said that M.T.B.E. "has been better for reducing toxics than anybody thought it would be," and has also helped reduce carbon monoxide emissions from cars. But experts say newer cars can control carbon monoxide without M.T.B.E., he said, and "you have to stack that up against the potential water risk."
No one knows just how many spills there have been, but the panel report estimates that in places where oxygenates are used, 5 to 10 percent of drinking-water supplies show detectable amounts of M.T.B.E.
The environmental agency considers M.T.B.E. to be a possible carcinogen because it has been shown to cause cancer in animals.
People, however, can smell M.T.B.E. at very low concentrations, and it makes water smell so bad that most will refuse to drink it.
M.T.B.E. makes up 3 to 5 percent of the national gasoline supply. If refiners had to suddenly compensate for that volume with other components, shortages and price spikes would result, the producers say.
"Americans can be paying more for dirtier air," said Terry Wigglesworth, executive director of the Oxygenated Fuels Association, a trade group of M.T.B.E. producers. A better approach, Ms. Wigglesworth said, would be steps to stop leaks and spills, which would protect drinking water from M.T.B.E.
But some analysts, noting that M.T.B.E. costs significantly more per gallon than gasoline, say that if the change is made slowly, the cost of fuel could drop.
The Clean Air Act amendments of 1990, which require oxygenates, also require a 15 percent reduction in toxic components in gasoline. The oil companies turned heavily to M.T.B.E. because it contains oxygen and because it boosts octane.
But the component can make water unusable, and that is one reason that in March California ordered oil companies to phase it out by 2002. Under the Clean Air Act, subject to the veto of the Environmental Protection Agency, California can develop its own clean air policies because pollution in Los Angeles is worse than in the rest of the country. The panel will also urge Congress to clarify the right of the E.P.A. and the states to regulate gasoline for environmental reasons that may not add up to a public health hazard.
Ms. Browner said the recommendations "are expected to confirm E.P.A.'s belief that we must begin to significantly reduce the use of M.T.B.E. in gasoline as quickly as possible, without sacrificing the gains we've made in achieving cleaner air." The panel and Ms. Browner said they did not want M.T.B.E. replaced by toxic components.
Oil companies used M.T.B.E. before the law required oxygenates.
"It's good, clean octane," said Jason Grumet, the executive director of the Northeast States for Coordinated Air Use Management. "M.T.B.E. is low toxicity and high exposure," but is "a pesky molecule," said Grumet, whose organization comprises the air pollution commissioners of the six New England states and New York and New Jersey.
After Congress required oxygenates, oil companies turned to M.T.B.E. for 85 percent of their needs. Ethanol or its derivative, E.T.B.E., which stands for ethyl tertiary butyl ether, make up most of the rest.
The study to be released Tuesday calls for further study of those ingredients, too.
Ms. Browner said she would like to preserve "the important role of renewable fuels like ethanol." But experts said the production of ethanol, which comes mostly from corn, is far too small to replace M.T.B.E.
When oxygenates were first required, in 1990, proponents said that putting oxygen into the liquid fuel would insure that engines produced more carbon dioxide, less carbon monoxide. In the intervening years, most cities have reduced their carbon monoxide, though, and a study released in May by the National Academy of Sciences found that neither ethanol nor M.T.B.E.
made much difference in controlling the bigger air pollution problem from cars, ground-level ozone, or smog.
New Jersey recently won permission from the E.P.A. to stop using extra M.T.B.E. in gasoline in winter, because it has solved its winter carbon monoxide problem, said Peter K. Page, a spokesman for the State Department of Environmental Protection, in Trenton. People complain about the smell of M.T.B.E. at the pump, Page said, and "the complaints seemed to correlate with the introduction of wintertime gasoline."
The wintertime gas had been 2.7 percent oxygen, by weight; the summertime standard, which the state continues to use, is 2 percent oxygen by weight. Asked about E.P.A. support for dropping the mandate, Page said, "That's fine with us."
In New York, Jennifer K. Post, a spokeswoman for the Department of Environmental Conservation, said, "We like it but obviously we have concerns about it."
Neither New York nor Connecticut has sought to drop M.T.B.E. Maine has, because of concerns about water.
Because states not included in the Federal mandate elected to comply, reformulated gasoline is now required in all or part of California, Connecticut, Delaware, Illinois, Indiana, Kentucky, Massachusetts, Maryland, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Texas, Virginia and Wisconsin.
"If anything is going to be introduced that replaces M.T.B.E., we want it to be researched, so we don't get the kind of surprises with whatever that is that we got with M.T.B.E.," Page said. But he added that hardly anything in gasoline was desirable. "Someday people will look at us driving gasoline-powered cars the way we look at our ancestors throwing chamber pots out the window," he predicted.