Dear EarthTalk: How clear (or not) are the links between the rising incidents of cancers around the world and the prevalence of synthetic chemicals in modern society?--Alberto Buono, Lee, MA
With the World Health Organization hinting that cancer could unseat heart disease as the leading cause of death around the world, it's no surprise that per capita cancer incidence is on the rise globally. In fact, cancer is the only major cause of death that has continued to rise since 1900. While it might depend on whom you ask, most researchers now agree that environmental factors--including exposure to chemicals and pollution--play a significant role today in determining who gets cancer and who doesn't.
A blue ribbon panel of cancer experts initially convened by President George W. Bush researched hundreds of studies and concluded in 2010 (in its 240-page report, "Reducing Environmental Cancer Risk: What We Can Do Now") that our exposure to chemicals, pollution and radiation is to blame for the uptick in cancer deaths. "The American people--even before they are born--are bombarded continually with myriad combinations of these dangerous exposures," the panel reported. "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 cited grim statistics about cancer's march, noting that 41 percent of Americans will be diagnosed with cancer at some point in their lives, with 21 percent likely to die from it. Cancer researchers fear that our reliance on chemicals is the main culprit, as borne out by hundreds of studies.
To wit, a 2000 study involving the examination of health records of more than 44,000 pairs of twins across Scandinavia found that "inherited genetic factors make a minor contribution" in causing most cancers but that "the environment has the principle role in causing sporadic cancer." A 2010 UK study, whereby researchers investigated the level...