A Washington, D.C., law banning free plastic bags is being closely watched. (Associated Press)

A law banning plastic bags from being given to customers for free in Washington, D.C., is being closely watched in many U.S. states.

The law came into effect Jan. 1 and requires retailers to charge five cents for every plastic bag. Several Canadian cities have implemented similar rules, and they've largely been supported by shoppers.

The jury is still out on whether the law will pave the way for U.S. states to follow suit, as many environmentalists hope. San Francisco is one of the only other major cities to ban plastic bags.

Some D.C. shoppers are driving to stores in neighbouring states where bags are still free, or they're simply refusing to shell out for a bag and will carry the items in their arms.

"I think it's unnecessary," said Daniel Koroma, 57, as he toted groceries home from a supermarket in a plastic bag that he'd paid for.

"They sell you the groceries, they should give you something to put them in."

The rules apply to anyone selling edible items, including bookshops, clothing stores and small gift shops.

Some residents have embraced it. Twana Littlejohn, who manages a Starbucks, said she feels good knowing that she's doing something for the planet.

"I've stocked reusable bags in my car so whenever I go shopping, I just have to pull one out," Littlejohn said. "It's not hard."

According to the U.S. Environmental Protection Agency, 3.6 million tonnes of plastic waste — including bags, sacks, and wraps — was generated in 2008, with barely one per cent being recycled.

The agency does not keep statistics on the effectiveness of fees or bans on bags.

Canada has made moves

Europeans have long accepted the idea of paying for bags and providing their own baskets, bags or nets to carry goods.

The concept has taken hold in Canada. Since July 1, Toronto has required retailers to charge five cents for a plastic bag.

Two large grocery chains, Montreal-based Metro and Toronto-based Loblaw, took it a step farther and decided to charge five cents per bag at all of their stores, regardless of whether a ban is in place.

Loblaw, which operates about 1,000 stores across Canada, started charging for plastic bags in April 2009 after a poll indicated that four in five Canadians supported the idea.

Loblaw reported it was using about 75 per cent fewer plastic bags.

Metro, which operates 600 stores in Ontario and Quebec, also reported it was using 70 per cent fewer bags after it began charging. Metro also reported that sales of reusable bags went up by five times since the fee was implemented July 1.

Sobeys has instituted a five-cent charge, but only for stores in Ontario.

With files from The Associated Press