Confusion centers on chemicals and cancer

After Kate Canada had her first child three years ago, phthalates was the chemical that health-conscious moms like her went out of their way to avoid. So she tossed the plastic toys and replaced them with wooden ones.

When she had a second daughter this year, BPA became the substance to fear. So she bought new baby bottles and got vigilant about stocking her pantry with all things BPA-free.

Then, a few weeks ago, she heard about an annual report from the President's Cancer Panel that, for the first time, painted a dire picture about potential cancer risks from a legion of environmental hazards. At that point, she threw up her hands.

"Parents shouldn't have to be chemists and shouldn't have to worry about every little thing," said Canada, 34, of Rodgers Forge. "It just seems to be never-ending. It's like, what's next?"

The panel's 240-page report urging more research and stronger regulations to protect the public from environmental chemicals that could cause cancer validated the work of scientists and environmental advocates who have long pressed for such safeguards. The three-member panel noted that people should limit their exposure to potential problem items such as pesticides, medical X-rays, plastic food containers and industrial chemicals. But with everything from drinking water to canned goods suspected as a threat, how should people try to limit these exposures? Or should they even bother?

Not everyone agrees that chemicals in the environment pose an urgent cancer threat. The American Cancer Society took issue with the panel's statement that environmental exposures have been "grossly underestimated," saying that the report is "unbalanced" in its implication that pollutants are a major cause of cancer. The organization feared the panel dismissed the notion that many more cancers are caused by lifestyle choices such as smoking and obesity. Cancer epidemiologists tend to agree.

"I do think we need to pay attention to environmental exposures, but compared to the very defined cancer risk factors, environmental exposures are pretty minor," said Dr. Kevin Cullen, director of the University of Maryland's Greenebaum Cancer Center. "The mistake would be to have people panic and make major changes around their lives and ignore other issues such as obesity and smoking."Consider that smoking accounts for about 30 percent of cancer deaths, while environmental exposure might account for as little as 5 percent, he said.

But Dr. Lynn Goldman, a professor of environmental sciences at the Johns Hopkins University's Bloomberg School of Public Health, says people can and should focus on major causes of cancer, as well as limit their exposures to toxic substances.

"We should look for all the ways that we can prevent cancer. To me that's the most reasonable way to go," she said. "Many health professionals underestimate the capacity that people have to have more than one idea in their brain at once. I think people are very smart. They can know that smoking causes cancer and that other things also cause cancer at the same time. I think they can handle that."

For instance, there are known carcinogens that people can avoid, she said, including radon that can seep into a home from the foundation and radiation exposure. A radon test can tell you whether your home has unsafe amounts of the gas and avoiding unnecessary medical X-rays can reduce radiation risk.

There are others: Benzene, present in gasoline and arsenic and found in some drinking water, has been linked to cancer.

But even some known carcinogens are on the market, and the public has little knowledge how to steer clear of them, Goldman said. Formaldehyde, for instance, is listed as a carcinogen according to the World Health Organization's International Agency for Research on Cancer. It's used to bind fragments in making certain plywoods. But when someone buys a piece of wood, it's unlikely a label will tell the buyer if there's formaldehyde in it, and no law mandates that a company do so, Goldman said.

Consumer advocacy groups are pushing Congress to pass the Safe Chemicals Act of 2010, overhauling the Toxic Substances Control Act passed 34 years ago. The cancer panel's report notes that just hundreds of the more than 80,000 chemicals in use nationwide have been tested for safety and that many are known carcinogens on the market with no regulation.

The current laws are so ineffective that just five chemicals are regulated by the Environmental Protection Agency, said Richard Wiles, senior vice president of the Environmental Working Group, who advises that people drink filtered water, avoid flame retardants in furniture and electronics, and eat organic produce to avoid exposure to pesticides.

While the panel's findings stressed that more research is needed to better understand the link between toxic chemicals and cancer, it also called for stronger laws and better oversight over chemicals, most of which are assumed benign.

"The most important thing we can do is to continue to research the potential impacts that industrial chemicals are having on cancer rates," said Fielding Huseth, an advocate at the nonprofit consumer group Maryland PIRG. "Right now, industrial chemicals are assumed innocent until proven guilty."

Wiles takes issue with the American Cancer Society's assessment that environmental concerns are overstated. While death rates for cancer have been declining in recent years, cancer in children has been on the rise for two decades, he said.

"They aren't smoking; there are no lifestyle choices that kids can make to decrease their risk," he said. "There's something else in the environment that's causing this very steady increase in cancer in children. The logical place to look is these chemicals that children are exposed to their first day in the womb."

But cancer experts are uneasy about such claims because they say there is still a lot of research to be done to draw a conclusive link between many chemicals and cancer.

Take BPA. Commonly found in plastics and the linings of cans, bisphenol-A has been linked to developmental and reproductive problems and cancer in animal studies. While the federal government says children should limit their exposure to BPA, it hasn't restricted its use, saying more information is needed. Local governments, including Maryland's legislature, have moved to ban BPA in baby bottles instead of waiting for more conclusive reports from federal agencies.

Huseth of Maryland PIRG points to a report from the Centers for Disease Control and Prevention that found that 93 percent of Americans have measurable levels of BPA in their bodies and some 200 studies linking the chemical, which mimics estrogen, to harmful effects.

Still, cancer experts note there's no definitive connection to cancer.

"We don't know the range of risk associated with BPA at this time," said Dr. Elizabeth Platz, a cancer epidemiologist at Johns Hopkins' Kimmel Cancer Center, who supports more research on BPA. "If people are worried and want to avoid it, that's a fine and good for the environment, too. But I don't think people should panic."

Canada says the alarm bells sounded about BPA are enough to get her change her lifestyle — just in case.

"There are obviously some concerns out there about BPA," she said. "OK, so that should be like the definitive thing. No more BPA in baby bottles, no more in cans, no more in our food supply. That should happen immediately, and it's frustrating that it isn't."

kelly.brewington@baltsun.com

Recommendations from the President's Cancer Panel

While there are still many questions on environmental exposures and cancer risks, the panel advises that the public take steps to reduce its exposure to chemicals. Here are some suggestions:

•Drink filtered water.

Avoid BPA and other plastic components by storing and carrying water in stainless-steel, glass or BPA-free plastic bottles. Microwave food in glass or ceramic dishes.

Limit exposure to pesticides by eating organic produce.

Avoid meat with antibiotics and added hormones as well as charred and processed meat.

Check home radon levels periodically.

Wear sunscreen for protection from ultraviolet light.

Source: The Baltimore Sun Health News