Smog Risk Found Higher for Children

A report by a Washington, D.C., environmental group says that children in California are at greater risk of contracting cancer from inhaling toxic air pollutants than adults.

The study, which was to be released today and focused on five areas of the state, maintains that a 2-week-old baby in the Los Angeles region has already been exposed to more pollution than the federal government deems acceptable over a lifetime.

By age 18, the same child will have inhaled enough contaminants to exceed the acceptable exposure level hundreds of times over, according to the study.

“The concentration of cancer-causing air pollution in California is so great that, just by breathing this air, children will accumulate cancer risks that are pretty astounding,” said Andy Igrejas, environmental health program director for the National Environmental Trust, the advocacy group that produced the report.

“This underscores the urgency of efforts to reduce the cancer risks. We have such a long way to go for the air to be healthy,” he said.

The study examined pollution concentrations in the Los Angeles region, the Bay Area, the San Joaquin Valley, the Sacramento Valley and San Diego. The findings echo those of other studies, including a report prepared three years ago by U.S. Rep. Henry A. Waxman (D-Los Angeles).

California is the nation’s smoggiest state and researchers have long known that air pollution contains a mix of industrial and automotive chemicals. Solvents, metals and unburned fuel not only contribute to smog and haze, but can cause cancer, reproductive harm and neurological damage.

Yet there is disagreement over just how harmful toxic emissions are and what should be done to reduce risks.

“If you live in an urbanized, industrialized society with a growing economy you’re going to be exposed to some level of toxic air pollution,” said Jerry Martin, spokesman for the California Air Resources Board.

Toxic Emissions

Each year, 102,000 tons of the most common toxic emissions are released in California. Traces of benzene from gasoline fumes, hexavalent chromium from metal-plating shops and diesel exhaust from trucks and buses are widespread.

In the four-county Los Angeles region, the state air board estimates toxic air contaminants cause 720 cancer cases per million people annually--a risk almost 1,000 times greater than the federal government’s acceptable limit.

That federal benchmark, however, is extraordinarily conservative. It seeks to limit the odds of a person’s contracting cancer from contaminants to one chance in one million. In contrast, the risk of getting cancer from sources such as food, cigarette smoke or X-rays, is about one in five.

Melanie Marty, chief of the air toxicology unit at the California Office of Environmental Health Hazard Assessment, said children are more vulnerable to pollutants.

They are more active and inhale relatively more air than adults, have less well-developed immune systems and undergo rapid growth, during which cells are more vulnerable to attack by carcinogens. Further, she said, some animal studies show that exposure to toxic chemicals early in life increases the risk of cancer in adult years.

“They are making some leaps in the way they estimate risk” in the new report, Marty said, “but their major point, that children have higher exposures than adults, that’s not disputed.”

But do kids get more cancer as a result? That is unclear, experts say. Theoretical risks do not always translate into actual cancer cases.

In a study published earlier this year, researchers from the state Department of Health Services and the Public Health Institute in Berkeley failed to detect any significant increase in childhood cancer among 7,000 children living near freeways, where toxic air pollution is substantial.

Similarly, smoggy California communities do not appear to have more deaths caused by lung cancer than other places. According to the state health department, Los Angeles County, one of the smoggiest places in the nation, averages 42 lung cancer deaths per 100,000 people annually, the eighth-lowest rate in the state and lower than the rates for rural Modoc and San Luis Obispo counties. Experts caution, however, that lung cancer comparisons are tricky because the disease has many causes.

More Controls Sought

Nevertheless, environmentalists, physicians and some parents have sought stronger protections to safeguard children from pollution.

“We’re finding shocking information about levels of exposure,” Waxman said. “It’s higher than anticipated and I’m concerned about the impacts on children. We have got to redouble our efforts to control toxic air pollution. It is a wake-up call to all of us.”

Under a 3-year-old state law, California has stepped up its monitoring of toxic air contaminants in communities and undertaken a review of state air pollution standards to ensure they protect children.

State health officials also have identified five toxic contaminants deemed especially harmful to children, and are preparing new measures to reduce them. Diesel exhaust is one of the worst sources, studies show, and dozens of smoky, old school buses are being replaced with cleaner models across Southern California to reduce children’s exposure to diesel soot.