Smoking is hardly allowed anywhere, so cigarette butts are piling up everywhere: outside doorways of public buildings, on bus platforms and outside subway stations — all the places a smoker might take one last drag before entering a smoke-free zone.

The battle of the butts has become the focus of a nationwide anti-litter campaign that is distributing handy portable ashtrays that allow smokers to cleanly pocket smoked cigarettes.

“Traditionally, people who smoke aren’t litterers, but they don’t think of their habit as producing litter when they throw it down on the ground,” said Jim Pavel, who is heading Buffalo’s cigarette litter prevention efforts as part of the larger Keep America Beautiful campaign.

Buffalo is one of about 50 cities participating in the campaign this year. Volunteers in the next few weeks will give away 1,000 portable ashtrays to start. After that, smokers or companies will be able to buy them at City Hall at cost, under $1 apiece. About two dozen cities kicked off the program last year.

The palm-sized ashtrays have a sliding door which reveals a metal compartment in which a cigarette can be snuffed and stored. The lid shuts snugly to protect clothing. The compartment is big enough for a few butts.

Similar ashtrays are more widely used in Europe, though some are available commercially in this country.

“I’d probably use it,” said Shirley Barker, echoing the sentiments of several others smoking during a break outside a Buffalo office building Monday. Even though ashtrays were visible on the plaza, cigarette butts were plentiful under foot.

The campaign, with funding from Philip Morris, is meant to raise awareness that cigarette filters are not biodegradable, as is commonly thought. Although they look like cotton, they are actually plastic. Besides being ugly, they can be dangerous, experts said.

“Its very purpose is to trap chemicals, so in those butts there are chemicals that can leach out into the soil and groundwater,” said Rob Wallace of Keep America Beautiful, headquartered in Stamford, Conn.

Litter experts say cigarettes are, by far, the country’s most tossed object, outpacing fast-food wrappers, caps and lids, and soda bottles, which come in a distant 2nd, 3rd and 4th, respectively.

Cigarette litter has grown as smoking has been banned from more and more places, and as cars have stopped including ashtrays as standard features. New York state banned smoking inside all public buildings three years ago, following the lead of California and Delaware. The American Cancer Society says 13 states now have similar laws.

Surveys have shown that smokers and even nonsmokers don’t consider cigarette butts to be litter, the way they would a soda can or cup, Wallace said.

During land and underwater cleanups in 2003, cigarette butts and filters accounted for 34 percent of debris collected, according to Keep America Beautiful. Food wrappers and containers represented 10 percent of trash.

On the Net:

Keep America Beautiful: www.kab.org