Some people carry their lunch to work in them. Others fill them with dog droppings. But millions of plastic shopping bags are never used again, and end up in garbage dumps or blow into storm drains, streams and the ocean, where they threaten animals that eat or become entangled in them.

Now, some officials on O'ahu and Maui want to ban plastic bags, which are not biodegradable, from supermarkets and other stores.

A ban took effect last month in San Francisco, and other Mainland cities are considering similar measures.

San Francisco now requires large grocery stores to offer paper bags or special "compostable" ones made from corn starch and other materials that aren't derived from petroleum, as plastic is. Customers also are encouraged to bring their own reusable bags made of cloth, netting or other materials when they shop.

City Councilman Donovan Dela Cruz said O'ahu must be more aggressive about such issues.

"We're in the middle of the Pacific, and we should be the most environmentally conscious city in the world, but we're way behind," said Dela Cruz, who introduced a bill banning plastic bags, as well as several other environmental proposals last month with Councilwoman Ann Kobayashi.

The proposed ban would apply to O'ahu businesses with annual gross sales of more than $1 million, and would take effect one year after council approval.

It would apply to all other businesses after five years.

Violators would face fines of up to $1,000 per day.

Some grocery and business groups oppose a ban, warning that it could drive up costs for their customers.

"Compostable bags and recyclable paper bags are up to 10 times more expensive than plastic, both in actual purchase price and in the shipping costs to Hawai'i," said Carol Pregill, president of the Retail Merchants of Hawai'i.

"Ultimately, these costs will be passed on to the consumer and will increase the cost of food and other products for Hawai'i's residents."

Instead, consumers should be encouraged to reuse plastic shopping bags to line waste baskets, clean up after pets, and other uses, Pregill said in testimony to the council.

TRADE GROUP OPPOSED

The Hawai'i Food Industry Association, which represents dozens of grocery stores and suppliers, also opposes a ban. To prevent bags from blowing away and polluting the environment, consumers should tie them in knots before throwing them away, said the group's president, Richard Botti.

The group also is encouraging recycling, and some stores have set out special bins where customers can return bags.

The collected bags are sent to the Mainland for recycling into plastic lumber and other products, Botti said.

But some environmental activists believe a ban would be more effective.

"Plastic is highly toxic, and we need to take steps now," said Lydi Morgan, a board member of the Sierra Club's O'ahu branch. "Plastic bags are just part of the problem, but this is a step in the right direction."

Morgan said she takes reusable cloth bags with her when she shops for groceries.

"It's not that hard," she said.

Some stores have begun selling reusable bags.

Botti said a ban on plastic bags would likely increase the demand for paper bags, however, and quickly lead to a shortage of them.

Several shoppers interviewed outside Honolulu grocery stores had varying opinions about the proposed ban.

Honolulu resident John Drahus said plastic bags are an ugly nuisance, and that he hopes the council outlaws them.

"I wish they would," Drahus said. "I don't like them. You find them everywhere on the street."

Some stores in his former home state, Ohio, offer customers discounts when they bring their own reusable bags to shop, he said.

Danielle Tuata of Mililani said she had questions about how a ban would work, but generally supported the idea.

"I guess I can bring my own, or leave a couple empty bags in the car at all times," she said. "I'll make that change. Anything to help out. Like anything else, it just takes time to get used to."

Downtown resident Lee Dickerson said he opposed a ban.

"I think it's environmentalists ... run amok," he said. "I don't know what huge difference it's going to be. A lot of people recycle plastic bags anyway, so I don't know what the big deal is, other than someone trying to have control over someone else's life."

HEARING IN JANUARY

The first committee hearing and vote on the ban likely will be held next month, and the bill could be passed as soon as February if three more council members join Dela Cruz and Kobayashi. Dela Cruz said he is willing to be flexible, but wants to explore the issue thoroughly.

"We need to figure out how to deal with plastic bags," he said. "It's better to be working toward the solution, than not finding any compromise and having status quo."

Mayor Mufi Hannemann's administration is studying the issue but has not yet taken a position.

Maui Councilman Michael Molina introduced a similar bill there in July, which would ban plastic bags for retailers with annual gross sales exceeding $250,000. After five years, the measure would apply to retailers of all sizes.

Maui's Recycling Office estimates that 50 million plastic shopping bags are used on the island each year — about 350 per resident. O'ahu, with a population six times larger, may use 300 million bags or more per year.

About half of O'ahu's trash is burned at the H-Power garbage-to-energy plant, and plastic bags make an excellent fuel, officials say. But about 340,000 tons of trash is buried each year in the landfill at Waimanalo Gulch, including millions of plastic bags.

Reach Johnny Brannon at jbrannon@honoluluadvertiser.com.

Make a difference. Donate to The Advertiser Christmas Fund.