SÃO PAULO, BRAZIL -- It took less than a year for residents of São Paulo, the world's eighth most populous city, to squash a new state law eliminating free plastic grocery bags, loved locally as mini trash can liners. But a growing number of smaller cities around the country have embraced similar laws, and a handful of other Brazilian states introduced plastic bag bans in late 2012 that have held firm.

São Paulo state's plastic grocery bag ban, introduced in January 2012 after being agreed to in May 2011 by the state's governor and supermarket trade association, kicked off a tug of war last year between consumers that felt they were being cheated by grocers, and public officials citing evidence of plastic bags' environmental burden, and their legitimate role in flooding problems in storm drains.

The goal was to drastically reduce the amount of single-use plastics bags that end up in São Paulo's garbage. Public statistics show that more than 2.4 billion plastic bags are consumed each month in the state, 90 percent of which end up in the trash.

A vast majority of Brazilians do get second use out of their grocery bags as liners for small trash cans, which are common throughout the home and office. The habit of carrying cloth bags or pulling small metal carts to weekly neighborhood produce fairs is ingrained for most Brazilians, and it was assumed transitioning this custom to grocery stores would come easy.

When the law took effect on Jan. 25, 2012, all grocery stores in the state had to offer customers heavy-duty reusable bags for purchase, biodegradable plastic bags sold at cost for BRL0.19 (US$0.10), or cardboard boxes for free, if the store had them available. Free plastic bags were no longer available.

Within two weeks, São Paulo's state prosecutors office and consumer rights agency Procon intervened in response to public complaints, mandating a 60-day buffer for markets to offer free bags or boxes to consumers that didn't bring their own. The issue bounced back and forth among state courts for months.

São Paulo markets were no longer obligated to provide free bags as of September 2012, but the state's supermarket trade association said its member-stores would continue with the traditional free bag and pursue "gradual change" in bag consumption, though no timeline was offered.

Other states followed São Paulo's lead in 2012, but passed plastic bag bans that have avoided consumer pushback by making stores responsible for cost.

Goias state's recently passed law, which will take effect in June, requires all food vendors to offer only biodegradable plastic bags at no cost to shoppers, or face thousands of dollars in fines. Espirito Santo state passed a similar law in late 2012.

The supermarkets association of neighboring Minas Gerais state won a January injunction in federal court to retain the option of charging BRL0.19 per biodegradable bag. The federal judge said that charging for bags would encourage consumers to make more environmentally conscious choices, and when a conflict arises between environmental protection and consumer choice, the court should favor the environment.

Others have declined to follow the trend. Parana state Gov. Beto Richa vetoed a bill in early 2012 that would have banned non-biodegradable plastic bags, proposing instead for funding public education efforts to gradually reduce plastic bag use over the next decade, voluntarily.