Cancers from Environment 'Grossly Underestimated'
Daily Exposures Cause Far More Cancers Than Once Thought, a Presidential Panel Says
By EMILY WALKER
MedPage Today Staff Writer
May 6, 2010—
Environmental carcinogens are responsible for a far greater number of cancers than previously believed -- a fact that suggests eradicating these environmental threats should be a priority for President Obama -- according to the report of a presidential advisory panel.
"The Panel was particularly concerned to find that the true burden of environmentally induced cancer has been grossly underestimated," wrote the authors of the report, "Reducing Environmental Cancer Risk: What We Can Do Now."
"The panel urges you most strongly to use the power of your office to remove the carcinogens and other toxins from our food, water, and air that needlessly increase health care costs, cripple our Nation's productivity, and devastate American lives," the report's authors wrote in a letter to President Obama.
The President's Cancer Panel was established by the National Cancer Act of 1971, when then President Richard Nixon declared war on cancer. The panel is required to submit an annual report to the president describing the status of the "war" and identifying both progress and barriers to continued advances.
The singling out of environmental causes for cancer in this year's report is considered a major -- and some said welcome -- departure from previous reports, according to a number cancer specialists contacted by ABC News and MedPage Today.
"For the past 30 years ... there has been systematic effort to minimize the importance of environmental factors in carcinogenesis," said Dr. Philip Landrigan, director of the Children's Environmental Health Center at Mount Sinai School of Medicine in New York City.
"There has been disproportionate emphasis on lifestyle factors and insufficient attention paid to discovering and controlling environmental exposures," he said. "This report marks a sea change."
Dr. Jennifer Lowry, a medical toxicologist at Children's Mercy Hospitals and Clinics in Kansas City, Mo., said the report finally lends a "voice that could be heard that the environment does play an important role in the health of all people of every age."
The report is actually a synthesis of testimony from more than two dozen experts in cancer, chemicals and environmental toxins.
Based on that testimony and research compiled over the last two years, report authors Dr. LaSalle Leffall, Jr., of Howard University and Margaret Kripke, professor emerita and University of Texas M.D. Anderson Cancer Center, concluded that the government has failed to prevent unnecessary exposures to carcinogens. The challenge for the Obama administration, they wrote, is to intensify research efforts into environmental toxins.
"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," Leffall and Kripke wrote in the letter to the president.
Among the potential exposures cited in the report were pesticides, fertilizers, pharmaceutical byproducts in the water supply, household chemicals and tanning beds. Emissions from cars, trucks and planes add to the toxic mix, the authors wrote.
But the authors said there was no evidence connecting the use of cell phones to increased cancer risk.
While Americans are exposed to thousands of chemicals each year, only several hundred of those chemicals have been safety tested, Leffall and Kripke said.
The study of environmental factors and their effect on cancer has been giving short shrift compared to studying lifestyle factors and genetic and molecular causes of cancer, the authors claimed.
But paging through the lengthy report, it was difficult to find solid science to back that strong statement.
"At this time, we do not know how much environmental exposures influence cancer risk and related immune and endocrine dysfunction," Leffall and Kripke wrote.
In an interview, Leffall said he hoped the report, if nothing else, would raise awareness that chemicals and other environmental toxins may be causing cancer and that more studies are needed.
"We think based on what we know, when you look at all the data, it just appears to us that there are areas where its been greatly under-reported," Lefall said. "We don't know 100 percent, but that's why we believe we need to do more research."
The National Toxicology Program, part of the Department of Health and Human Services, does list some chemicals such as benzene and formaldehyde and some substances including tobacco as carcinogenic, but environmental factors, such air pollutants and naturally-occurring chemicals, are less well-understood.
Public awareness about some compounds, such as bisphenol A (BPA), has increased in the past year as a handful of studies and report linked the ubiquitous chemical -- widely used in plastics such as baby bottles and other drink containers -- to metabolic disorders, heart disease and male sexual dysfunction.
Also, the U.S. Food and Drug Administration recently announced it would review safety data on another common chemical, triclosan, which is used in antibacterial soaps and washes, toothpastes and cosmetics, after lab tests on animals were concerning.
In the report, Leffall and Kripke recommended that physicians routinely ask about their current workplace and living environment as a routine part of collecting patient history.
They also recommended:
Conducting a thorough assessment of workplace exposures and cancer risks;
Creating a more coordinated and transparent system for enforcing environmental health standards;
Increasing funding for federal research into occupational and environmental epidemiologic cancer research;
The Environmental Protection Agency should lower its current maximum standard for radon exposure, and the public should be better informed about the risks of radon;
Providing better care to military personal who were exposed to nuclear fallout.
Radiation exposure has long been recognized as a cancer risk, but this latest report from the President's Cancer Panel claims that patients and healthcare professionals are not completely aware of radiation exposure from imaging techniques such as computed tomograpy (CT) scans -- a radiation exposure that might be increasing with the use of whole body scans and virtual colonoscopy.
And while the report issued a call for increased emphasis on dialing down the radiation exposure with CT, the government may actually be out in front on this issue; the FDA recently proposed new safety requirements for manufacturers of CT scanners and fluoroscopic devices. Those new requirements are designed to reduce unnecessary radiation from medical imaging.
CORRECTIONS:
A previous version of this story mistakenly named Margaret Kripke, professor emerita and University of Texas M.D. Anderson Cancer Center, as Vivian Smith.
The story also misspelled the name Dr. LaSalle Leffall, Jr. as Dr. LaSalle Lefal.