Aspen, Colorado. Cadmium, contained in the street de-icer magnesium chloride, is a human carcinogen, according to the Tenth Annual Report of the U.S. Department of Health and Human Services. There is no safe level of cadmium -- a soft, silver-white metal -- upgraded from "Reasonably Anticipated to be a Human Carcinogen" to "Known to be a Human Carcinogen."
Cadmium has been linked to both breast cancer and prostate cancer. It has pulmonary toxicity and causes lung cancer. Cadmium is the principal killer in cigarette smoke.
According to a summary chapter from the Toxicological Profile for Cadmium released by the Agency for Toxic Substances and Disease Registry (ATSDR), "Most of the cadmium that enters your body goes to your kidney and liver and can remain there for many years." The report goes on to say that cadmium can enter your body from the food you eat, the water you drink, from particles attached to the air or from breathing cigarette smoke.
An Aspen Times series on mag chloride said Aspen air has elevated levels of both cadmium and arsenic. Dr. Stephen Strum, founder of the Prostate Cancer Research Institute (PCRI) in Marina del Rey, Ca., told the Aspen Free Press: "Cadmium is definitely associated with prostate cancer risk." When told that Aspen had used the street de-icer magnesium chloride containing both cadmium and arsenic, he said, "This is certainly cause for alarm."
In 1982 a medical study showed that cadmium levels found in tissue of removed prostate tumors were eight times greater than cadmium levels in normal prostate tissue. Another study found a 25-fold increase in cadmium levels of prostate tumors.
A 1997 medical study has found an increased risk for lung cancer in cadmium-exposed workers, but says: "the association was significant only with the cadmium-exposed workers who had also been exposed to arsenic," also contained in the street de-icer magnesium chloride.
According to a report by the Occupational Safety and Health Administration (OSHA), "Because of the body's ability to accumulate and store cadmium over long periods of time, the loss of kidney function may develop even after a reduction or cessation of external cadmium exposure."
OSHA goes on to say, "exposure to cadmium causes cancer, kidney dysfunction, reduced pulmonary function, and chronic lung disease indicative of emphysema." Of course these conditions don't occur overnight and most people can't tell by smell or taste that cadmium is present in air or water ... water which flows into rivers and streams from roads coated in cadmium-laced magnesium chloride to keep ice melted.
Federal guidelines continue to call for less and less cadmium exposure in the workplace, according to OSHA, "because a number of studies of workers suggest an association between occupational cadmium exposures and increased deaths from cancer, most notably prostate cancer."
When I was diagnosed with prostate cancer, the first question a physician asked me was, "Have you been around cadmium?" I didn't know it then but I had been wading through cadmium in mag chloride applied to the streets of Aspen for several winters. Aspen City Council has an on-again-off-again history with mag chloride. The last winter that I recall the de-icer on local streets to any extent was, for a time, during the winter of 2001.
The Agency for Toxic Substances and Disease Registry says, "There are no good effects from taking in cadmium. Breathing air with high levels of cadmium can severely damage the lungs and may cause death. Breathing air with low levels of cadmium for long periods of time (for years) results in a buildup of cadmium in the kidney and may result in kidney disease." Other effects that could occur after breathing cadmium for a long time, besides cancer, are lung damage and fragile bones.
Cancer statistics indicate that the prostate cancer rate in Aspen has been climbing. It seems like a lot of men here, in their late forties and early fifties (young for prostate cancer), are getting it. It's difficult to pinpoint the cause when one gets cancer. Usually it's a multiplicity of factors, including genetic predisposition, age, exposure to environmental carcinogens and general health. And, according to studies, it's not that cadmium necessarily creates prostate cancer from scratch. Most men, as they age, develop prostate tumors, but they are held in check by tumor suppressor genes and remain latent, i.e. harmless.
If these tumor suppressor genes somehow get mutated, a harmless prostate tumor becomes "clinical," i.e. needing cancer therapy. One tumor suppressor gene is the p-53. Clinical tests indicate that cadmium -- contained in the street de-icer magnesium chloride -- even at non-toxic levels, "impairs p-53 function," not only for prostate cancer but also for lung cancer and some lines of breast cancer.
Sterling Greenwood, publisher-editor of the Aspen Free Press, has been battling prostate cancer for seven years. He and other residents of Aspen, Colorado campaigned successfully to end use of magnesium chloride on the roads. Visit the Aspen Free Press online at http://www.aspenfreepress.com