Warning: Gassing up is hazardous to your health ... and the planet’s

Picture a typical hazy California afternoon. You drive your car to a gasoline station, sidle up to a gas pump, and find a warning label dangling off the hose. Driving a petroleum-powered car contributes to global warming, the label tells you. How many times do you have to see such a label before it affects either your feelings or your decisions — if ever?

Two cities in California may soon attempt to find out. Last week, the Berkeley city council voted to move forward with a plan that would require fuel stations (even electric charging stations and those offering biodiesel) to affix small-but-conspicuous signs to pumps, reminding drivers about the role of petroleum-based fuels in climate change. San Francisco is considering a similar proposal. Two other Canadian cities — West Vancouver and Fredericton — have also weighed proposals for gas-pump-label bylaws in the past few months.

The gas-pump warnings, hatched by environmental advocates, seem an unusual way to use labeling laws. In the past half –century, warning labels have served a number of purposes: to make hidden risks visible, to change behavior, or merely to limit the liability of a corporation making a product (consider this warning label from a sports equipment company: “No helmet system can prevent concussions or eliminate the risk of serious head or neck injuries while playing football”).

The gas-pump warnings mix a message of consumer responsibility and political awareness. They were inspired, in part, by the warning labels that appear on cigarette cartons. Rob Shirkey, a Toronto lawyer and one of the leaders of the Canadian labeling campaign, told Al Jazeera “there's actually a stronger rationale for this sort of intervention than there is for the labels on tobacco packages” because “the harms from burning fossil fuels impact us all.” In 2013, Shirkey founded an organization called Our Horizon, which toured across Canada for two months promoting graphic labels for gas pump handles featuring images of caribou, a drought-afflicted landscape and a dying coral reef. Emily Kelsall, a 16-year-old in West Vancouver, heard about the campaign on the radio and brought a formal proposal to her city council. On the opposite side of the country, a group of university students has approached the Fredericton, New Brunswick, city council about adopting labels.

Independently, the Bay Area chapter of the international environmental network 350.org proposed to both Berkeley and San Francisco a friendly graphic label of a cartoon car emitting a small brown cloud, with a lengthy explanation: “A typical passenger vehicle burning one gallon of fuel produces on average almost 20 pounds of tailpipe carbon dioxide,” reads a portion of the label. The group now plans to promote labeling initiatives among dozens of city governments all over California, according to Jamie Brooks, one of its organizers. The Canadian and Californian activists have since been collaborating online.

Climate change is, of course, an infinitely more complex problem than smoking, and one cannot downsize the footprint of the entire global economy with warning labels and modest consumer behavior changes alone. Still, the activists argue that personal driving and gasoline use are part of the picture. “In order to deal with transportation emissions, you have to deal with behavior,” Brooks said to Al Jazeera. Transportation was responsible for more than one-fourth of U.S. greenhouse gas emissions in 2012.

But could a sign on a gas pump prompt someone to rethink car-commuting habits?

Research says labels can sometimes shift attitudes, and the graphic warning labels that adorn cigarette cartons in Canada (complete with disturbing images of diseased lungs and cancer patients) have been especially effective. In the United States, any label with particularly strong images or tough language face legal obstacles. The FDA’s proposals for graphic cigarette labels were struck down in 2012 as a violation of tobacco companies’ free speech rights. Bay Area activists have offered mild, fact-based language for gas-pump labels, which they hope will avoid lawsuits. The Western States Petroleum Association, an oil industry lobbying group, has already warned Berkeley that it believes the gas-labeling proposal is unconstitutional.

Critics of the proposals also insist that gas labels aren’t the best way to influence transportation decisions. By the time you arrive at a gas station, some decisions have already been made — as Berkeley city councilmember Susan Wengraf pointed out during a council meeting last week. “I think at the fuel pump it's too late. If you've got a car, you've got to put fuel in it,” she said.

Shirkey insists such criticism misses the point. The labels would help create “a social environment that favors reform,” he says. For years, it’s been hard for environmentalists to stoke public concerns about climate change, which can seem like a large, unwieldy and abstract problem. Shirkey believes that the labels put the responsibility for global warming “in the palm of one's hand.”

San Francisco and Berkeley could put such ideas to the test by next year, and advocates hope other cities may eventually join them.