If the air pollution problem on the East Coast seems a little worse than usual this fall, it may be because of the gubernatorial campaings going on here in New Jersey and down in Virginia. The "negative advertising" in which too much of the country was surfeited last autumn is back again, as polluting as ever, in this year's only two statehouse contests.

It futile to rail against the practice. But sometime, somewhere, somebody is going to have to reckon the costs of winning votes in a way that poisons the whole political process.

In New Jersey, two men with rather distinguished careers as legislators are opposing eachothr for governor. Thomas H. Kean, the Republican, is a former speaker of the assembly, a political moderate with a long family tradition of public service. James J Florio, the Democrat, is a former state legislator who was elected to the House of Representatives in 1974 and has built an eviable record as a leader on transportation and environmental issues.

Both men have excellent personal reputations and both would seem to have some positive ideas to offer.

But you listen to their campaign ads and this is what you hear: from the Florio camp comes the charge that Kean is involved (you won't believe this) in a big-money scheme to launch a dangerous uranium mining venture in north New Jersey. His tax plan is all for Exxon and Gulf.

From the Kean camp, the reply is that Florio is a hopeless big spender and the political clone of outgoing Gov. Brendan Byrne (D). (No matter that Florio ran against Byrne in the primary four years ago and trounced Byrne's handpicked candidate in the primary last June.)

Down in Virginia, the candidates are two personable young conservatives, Lt. Gov. Charles S. Robb (D) and Attorney General Marshall Coleman (R). Both men happen to be ex-Marines, and the camaraderie of the corps might be though sufficient immunity against mudslinging. Not so.

Robb suggested in a sly commercial that Coleman might be squishy-soft on crime because he had once said that "marijuana is not a serious criminal problem." Rather than demanding proof of the dubious proposition that it is such a problem, Coleman put on his own ad, inquiring whether Robb had been "smoking something."

Just to complete this elevated dialogue, Robb replied that he happened to be a non-smoker, quickly adding that, of course, he had nothing against the tobacco industry.

What are voters to make of this nonsense? I think it's very clear what they make of it. It makes them sick. It is a libel on the voters of Virginia and New Jersey to suggest that they are capable of responding only to this kind of drivel.

I think the voters of New Jersey-or any of the other older industrial states-are aware of the drain of manufacturing jobs, of the competitive treats of the low-cost energy centers in the South and West, and of the needs for better education and more efficient delivery of services for the dispossessed in the cities.

Similarly, I think the voters of Virginia-like those in the other growth states-are aware of the strains the new industry is placing on the environment and the public-service agencies, of the balancing act that will be required to preserve the virtues of the state in a period of rapid expansion.

To chatter at these voters about imaginary devils of uranium or mariguana or other nonsense is to insult them-and turn them away from the polls.

Why do candidtes do it? They do it preeemptively, because they think the other guy will take some cheap shot against them if they don't get in their own knee to the groin first.

Joe White, the New York ad man handling the Florio campaign, said, "I used to think that negative advertising was something you used only at the very end of a campaign-if ever. But I did radio for a lot of Democratic senators in 1980, and I saw a lot of negative ads, used early, to undermine our guys, and they were very effective. I'm not going to let that happen to Jim (Florio), so we've kept at least one negative ad going all the time."

That may make sense as a tactic, but it's like the merchant who sticks a "fire sale" sign in the window and just keeps it there. Eventually, people figure out that he's selling shoddy goods.

Unless and until the politicians and their hired guns recognize that theunremitting negativism of their ad campaigns depoils the very process in which they areinviting the voters to take part I think the public is going to be increasingly turned off. And the public will be right.