Washington ? An expert panel that advises the president on cancer said Thursday that Americans are facing “grievous harm” from chemicals in the air, food and water that have largely gone unregulated and ignored.

The President’s Cancer Panel called for a new national strategy that focuses on such threats in the environment and workplace. It called those dangers “underestimated.”

“With the growing body of evidence linking environmental exposures to cancer, the public is becoming increasingly aware of the unacceptable burden of cancer resulting from environmental and occupational exposures that could have been prevented through appropriate national action,” the panel wrote in a report released Thursday.

Currently, federal chemical laws are weak, funding is inadequate and regulatory responsibilities are split among too many agencies, the panel found.

Children are particularly vulnerable because of their smaller bodies and fast physical development, the panel found. The report noted rising rates of cancer in children, and it referred to recent studies that have found industrial chemicals in umbilical-cord blood, which supplies nutrients to developing fetuses.

“To a disturbing extent, babies are born ‘pre-polluted,'” the panel wrote, adding that health officials lack critical knowledge about the chemicals’ impact on fetuses and children.

In addition, the government’s standards for safe chemical exposure in the workplace are outdated, it said.

In 2009, about 1.5 million American men, women and children had cancer diagnosed, and 562,000 people died from the disease.

The panel found that the country needs to overhaul existing chemical laws, a conclusion that has been supported by public health groups, environmental advocates, the chemical industry and the Obama administration.

The current system places the burden on the government to prove beyond a doubt that a chemical is unsafe before it can removed from the market. The standards are so high that the government has been unable to ban chemicals such as asbestos, a widely recognized carcinogen prohibited in dozens of countries.

About 80,000 chemicals are in commercial use in the United States, but federal regulators have assessed only about 200 for safety.

A bill filed last month by Sen. Frank Lautenberg, D-N.J., the Safe Chemicals Act of 2010, would shift the burden to manufacturers to prove the safety of new chemicals before they can be used. It would also require companies to give safety data for chemicals already on the market to federal regulators.

The cancer panel called that bill a good starting point. Still, it said, the government must look beyond individual chemicals to the cumulative effect on humans from exposure to multiple chemicals, and must consider how small amounts of a chemical can cause subtle changes in the human body that can result in cancer years later.