In the four decades since plastic bags became standard in grocery stores, New York has been haunted by these diaphanous, crinkly ghosts. They cluster in drains, spill out of garbage cans and tangle in trees. Together with old MetroCards, Anthora coffee cups, and disintegrating copies of The New York Post, they have become part of the city’s visual landscape, the kind of everyday objects so pervasive that they seem invisible.

They may soon begin to disappear, though. Beginning March 1, single-use plastic carryout bags will be banned in New York State. “For far too long these bags have blighted our environment and clogged our waterways,” said Gov. Andrew M. Cuomo in a statement proposing the ban last year.

Plastic bags will not vanish: Enforcement will be lenient at first, and the law allows a number of exceptions, from the expected (dry cleaning, food delivery) to the niche (bulk-buying live insects). But if the ban is successful, these now-familiar objects may eventually become artifacts of a New York City past.

When Sho Shibuya, a graphic designer, moved from Tokyo to New York in 2011, among the first things he noticed was the abundance of plastic bags. He estimates that he has now collected about 200, some of them pictured here.

In treasuring things other people consider trash, Shibuya cites a Shinto belief that every object has a spirit. “We believe every single object has a god inside, and that’s why we cherish things. Even a plastic bag, even a cigarette butt.”

As a collector, Mr. Shibuya was drawn to the beauty of the bags as design objects, with seemingly infinite, slight variations on the same handful of themes: a smiley face, a bunch of purple flowers, a graphic repeating sans serif “THANK YOU,” a curling “Thank you for shopping here!” banner. “Everything is so perfect to me,” he said.

These imprints are not copyrighted and difficult to trace, but, Shibuya points out, there is an informal taxonomy to New York City’s plastic bags, apparent to anyone paying attention.

“The plastic bag is a miracle of design,” said Susan Freinkel, the author of “Plastic: A Toxic Love Story.”

The original plastic shopping bags were designed by the Swedish engineer Sten Gustaf Thulin and patented by Celloplast in 1965, but they did not become common in grocery stores until the early 1980s.

“At first people really didn’t like them,” Freinkel said. “They didn't think they were strong enough. They didn’t like that the checkout people at the counter had to lick their fingers to pull it off the rack.”

“It’s an amazing engineering feat,” Freinkel said. “You’ve got this puff of polyethylene that’s waterproof. It’s durable. It’ll last a long time. It can carry a thousand times its weight. It’s an incredible product. But it was designed with no thought in mind to what happens to it once you get those groceries home.”

And plastic, as one lamination company boasted in a 1985 advertisement, “is forever.” It does not biodegrade but breaks down into ever smaller pieces, which are breeding grounds for bacteria and can carry toxic chemicals into food and water.

Plastic bags are also particularly difficult to recycle: When mixed in with ordinary recycling, they tangle and snarl in the machinery at recycling plants. Often the only option is to return them to retailers for collection, a step few consumers take.

The spread of plastic was not inevitable, according to Rebecca Altman, a sociologist who is writing a book on the subject.

“Think of the intersection of all of the innovations that have come together to make a plastic bag possible,” Altman said. “From the idea of a supermarket and prepackaged food and the geographical layout of a city such that we’re separated from food, all the way through to all of the innovations required to make polyethylene in the first place.”

Now they are part of the experience of the city itself. “Can you imagine the soundscape without that crinkle, crinkle, whispery sound?” Altman said. “We didn’t have that sound, at some point, in our ears.”

Shibuya, who supports the bag ban, considers his collection a kind of “yearbook”: something that records the feel of a particular time and place before it changes.

When he first arrived in New York, Shibuya noticed that neighboring delis would all carry smiley face bags, but each face had a slightly different expression. The variety, he said, seemed to sum up the spirit of the city. “There are so many people. So many plastic bags.”

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