How Munich plans to rid its air -- and Europe -- of exhaust pollutants

The Bavarian capital is seizing the bull by the horns - and polluters by the mufflers. After a decade-long West German federal ''taboo'' on introducing unleaded gas , Munich is going ahead with measures of its own without waiting for the rest of the country.

''Over the long term,'' says the city's environment expert, Rudiger Schweikl, ''we hope that there will be an unleaded pump at every gas station so that it will gradually go beyond experimental cars to (wide general) use of unleaded gas.''

This, he points out, could help clean up the 90 percent of city air pollution analyzed as being caused by auto exhaust.

Back in 1971 the federal government put a ban on unleaded proposals, Dr. Schweikl says. The then center-left federal government has by now shifted to a center-right government. But the present federal position is still negative - this time on the grounds that it would be pointless for West Germany to stiffen its car-emission standards without getting agreement from neighboring countries.

At present, West Germany's legal ceilings on lead in regular gas are 0.15 grams per liter, compared with 0.4 grams per liter for most West European countries, .02 grams per liter for Japan, and .013 grams per liter for the US.

Waiting for the rest of Europe, Dr. Schweikl fears, would mean another five to 10 years before anything at all was done.

Munich's impulse may seem tiny, indeed. But the hope is that other cities will emulate this example, that a net of lead-free gas pumps will be established in the country, and that gradually, private car owners will also shift to cars using lead-free gas in their own efforts to clean up the air they breathe.

A major disincentive to switching to unleaded gas is the additional cost. Cars outfitted to take unleaded gas (and thus the catalytic converter that can be used with unleaded gas to remove some 90 percent of carbon monoxide, hydrocarbons, and nitric oxide) are more expensive than ordinary cars.

Gas mileage is also somewhat lower, and the catalyst is a further expense - though Dr. Schweikl notes one savings. Mufflers last twice as long when the worst pollutants are filtered out of the exhaust.

The sheer availability of the cars is no longer a problem, however. Both the US and Japan have had stricter emission limits than Western Europe since the mid-1970s, and West German auto manufacturers are already producing for these markets. Nor is the gas itself a problem, since one West German petroleum company - Aral - is already refining unleaded gas.