American Cancer Society releases new list of possible carcinogens

HAWAII ISLAND—Most of us have learned to associate cigarette smoking with cancer, but the American Cancer Society (ACS) reminds us that there are a lot more things we may encounter every day that we should be aware of. A new report from the ACS on suspected carcinogens has rounded up 20 substances and practices that could be just as dangerous smoking cigarettes. The ACS hopes to compel agencies responsible for public health and safety to study these potential carcinogens and increase awareness about their effects. Here’s the list:

• Lead and lead compounds
• Indium phosphide
• Cobalt with tungsten carbide
• Titanium dioxide
• Welding fumes
• Refractory ceramic fibers
• Diesel exhaust
• Carbon black
• Styrene-7,8-oxide and styrene
• Propylene oxide
• Formaldehyde
• Acetaldehyde
• Dichloromethane, methylene chloride (DCM)
• Trichloroethylene (TCE)
• Tetrachloroethylene (PERC, tetra, PCE)
• Chloroform
• Polychlorinated biphenyls (PCBs)
• Di(2-ethylhexyl) phthalate (DEHP)
• Atrazine
• Shift work

The ACS study details the ways these substances are used and what is already known about them. Some of the items are found in the islands more than others, among them Tetrachloroethylene (otherwise known as PERC), which is used in dry cleaning and is proven to cause liver cancer and leukemia in rats. Epidemiological studies have also linked it to esophageal and cervical cancers, as well as non-Hodgkin’s lymphoma. It can be found at any local dry-cleaners.

Titanium dioxide has been established as a cancer-causing agent in several animal studies, a factor that tags it as a possible carcinogen for humans. Titanium dioxide is found in many everyday items, including cosmetics, paint, varnishes, lacquers, paper, plastic, ceramics, rubber, and printing ink.

“There is conflicting evidence as to whether the nanoparticles of titanium dioxide can pass through the skin,” the report read. “If they can, the presence of titanium dioxide in a large variety of cosmetic powders and creams may be a cause of concern.”

Also familiar to island residents are the odorous fumes of diesel exhaust. These fumes have been linked to lung cancer among numerous animals, truck drivers, and workers in the automotive industry.

Here’s one for people who think that they will avoid cancer by smoking marijuana instead of cigarettes: Styrene has been identified as a suspected compound; it is found in marijuana and cigarettes and is also used to make Styrofoam.

The only non-tangible carcinogen on the list is something familiar to those who have to work two jobs to make ends meet. Shift work has been linked to cancer in a number of studies ... the theory is that by being exposed to light during periods of darkness, your biological circadian rhythm is interfered with, causing a biochemical disruption. Cases can be found everywhere, varying from all night grocery stores, hospitals, and factories. Here in Hawaii, all the major hotels have large numbers of employees working through the night.

“There is significant concern among the public about substances or exposures in the environment that may cause cancer, and there are some common occupational agents and exposure circumstances where evidence of carcinogenicity is substantial but not yet conclusive for humans,” explains Elizabeth Ward, Ph. D., vice president of Surveillance and Health Policy Research at the American Cancer Society and lead author of the report. “The objectives of this report are to identify research gaps. ...”

Ward said the list prioritized these 20 agents based on evidence of widespread human exposures and potential carcinogenicity in animals or humans.