LOS ANGELES: Once upon a time, California's energetic public health lobby concentrated on trying to stop people from smoking, or drinking beer, or making a daily pilgrimage to their local fast-food restaurant.

Now, having presumably run out of other things to ban, they have launched a crusade against a naturally occurring green mineral.

Politicians in Sacramento, the state capital, are on the verge of approving a motion to strip serpentine of its status as California's official "state rock", because it can contain chrysotile, a type of asbestos believed to cause an incurable form of cancer called mesothelioma if its dust particles are inhaled.

The move is backed by several well-funded charities and consumer rights groups, who point out that 2500 Americans die from mesothelioma each year.

A motion to "defrock the rock" has already passed the state Senate and is about to be considered by its other house, the Assembly.

"California is health conscious," said Gloria Romero, the Democratic state Senator behind the motion. "This is not about being anti-rock. But why do we need a rock? We know that California has the highest rates of mesothelioma deaths in the nation and we don't think it's appropriate to be celebrating as the state rock something which contains asbestos."

Senator Romero's efforts to downgrade the green mineral have provoked a furious response from historians and geologists.

Though asbestos now has a dirty name, geologists claim serpentine is relatively harmless in its naturally occurring state. Legislators are merely vilifying the substance for political ends, they say.

"There is no way anyone is going to get bothered by casual exposure to that kind of rock unless they were breaking it up with a sledgehammer year after year," Malcolm Ross, a former employee of the US Geological Survey, told the New York Times.

"If they keep the asbestos issue bubbling, it means money for politicians, money for lawyers and money for scientists to investigate."

John Sullivan, president of the Civil Justice Association of California, said: "I believe compensation lawyers would feel they've struck gold if they can also bring lawsuits over naturally-occurring asbestos."

Stanford environmental historian Jon Christensen described the opposition to serpentine as scientifically illiterate.

A campaign against the proposed legislation is now bubbling away on twitter.

- Independent