A stone wall made of potato chips

California Atty. Gen. Jerry Brown announced last week that he'd settled lawsuits against leading makers of potato chips and French fries over levels of a cancer-causing chemical in their products.

At first blush, this looked like a laudable example of the public and private sectors working together to safeguard consumers. In reality, it was a textbook illustration of how companies all too often have to be dragged screaming and kicking to do the right thing.

"That's a fair description of what happened here," said Ed Weil, the supervising deputy attorney general who oversaw the case.

"We had to fight tooth and nail with these people. It was very frustrating."

The lawsuit centered on a chemical called acrylamide, which has been listed as a cancer-causing substance in California since 1990. Acrylamide is used industrially for sewage treatment.

According to the state's Office of Environmental Hazard Assessment, "a number of scientific studies indicate that acrylamide can cause cancer in laboratory animals, and available information suggests that acrylamide is likely to cause cancer in humans."

The Environmental Protection Agency has determined that long-term exposure to acrylamide can damage people's nervous systems and lead to paralysis and cancer.

But it wasn't until 2002 that Swedish scientists discovered that acrylamide is naturally produced when potatoes and other starchy foods are cooked at high temperatures, making popular snacks like potato chips and French fries potentially carcinogenic.

It remains unclear what danger the levels of acrylamide in food pose to people. The Food and Drug Administration is still researching the matter.

But it seems reasonable to think that when the Swedish findings were announced, food companies would have immediately taken steps to alert customers to the possible health hazard.

They didn't do that. They stayed mum.

In 2005, then-Atty. Gen. Bill Lockyer filed suit against a number of food companies and fast-food restaurant chains demanding that they disclose acrylamide dangers as per the requirements of California's Proposition 65.

Enacted in 1986, Proposition 65 requires the state to publish an annual list of chemicals known to cause cancer and requires businesses to warn people about the presence of any substance on the list.

As Weil recalled it, California's lawsuit began "a slow, punishing, inch-by-inch process" during which the companies circled their wagons and tried repeatedly to have the case dismissed.

They argued that there was no proof that acrylamide in food was dangerous to humans. They argued that states shouldn't be meddling in a federal matter. They argued that their 1st Amendment rights were jeopardized.

The first breakthrough in the case came late last year when McDonald's, KFC, Wendy's and Burger King agreed with the state to post acrylamide warnings in their restaurants and to pay civil penalties and legal costs.

In January, Procter & Gamble Co. agreed to reduce the acrylamide in Pringles by 50%. As a result, the company won't be required to include an acrylamide warning on its packaging.

Other companies, though, dug in their heels. They included Frito-Lay Inc., maker of Lay's and Ruffles and the dominant seller of potato chips statewide; Kettle Foods Inc., maker of Kettle Chips; Lance Inc., maker of Cape Cod chips; and H.J. Heinz Co., maker of Ore-Ida French fries and tater tots.

Weil said the companies refused to accept state regulation of their products or even to consider warnings on packages. The impasse finally ended a couple of months ago when the judge in the case rejected the companies' motions for dismissal. "It became clear that we'd be going to trial and that this was a case we could win," Weil said.

Under the terms of the settlement, Frito-Lay agreed to reduce the amount of acrylamide in its chips by about 20% over three years and to pay $1.5 million in fines and legal costs. It will get $550,000 of that amount back if it can cut the amount of acrylamide in its products within a year and a half.