Cancer Causing Toxins On The Job And At Home - Chapter 2 What Causes Cancer: Cancer

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Cancer-causing toxins on the job and at home

Some jobs, especially those in mining or manufacturing, expose workers to toxic chemicals and substances, some of which have been linked to an increased risk of cancer. Fortunately, thanks in large part to the federal Occupational Safety and Health Act of 1970, exposure to such toxins is regulated and monitored. Still, it is estimated that workplace-related toxins cause about 5% to 15% of cancers in men, and 1% to 5% of cancers in women. If you are concerned about cancer prevention, and especially if you work in manufacturing or industrial settings, it is wise to familiarize yourself with the chemicals listed in this report. You may also encounter some of these chemicals, such as benzene (found in gasoline and industrial glues) and wood dust (produced when working with wood) in the course of your everyday life, even if you don't work in a risky industry.

But to put this risk in perspective, remember that it is the duration of exposure that determines your risk. Inhaling an occasional whiff of glue does not represent a serious level of risk, but working in a glue factory or in a plant that uses beryllium might.

In addition to known carcinogens, there are a number of other probable carcinogens. These include diesel exhaust (a possible cause of lung cancer), formaldehyde (associated with nose and nasopharynx cancers), and workplace exposure to petroleum refining. Air pollution, water contaminants, and pesticides are all examples of toxins in the environment. Such toxins can damage genes within cells, initiating the cancer process. Bladder cancer, for instance, has been linked to arsenic in drinking water.

For the most part, however, air and water pollutants are not as significant a cancer risk as workplace carcinogens. Air pollution, for instance, has been linked to a very small percentage of lung cancers. The Environmental Protection Agency (EPA) estimates that about 1% of lung cancer deaths per year are related to urban air pollution, which is a much smaller proportion than those associated with tobacco smoke. Experts also believe that the cancer risk from drinking tap water is probably minuscule, if it exists at all. Thus far, no clear evidence has emerged linking water contamination to cancer. Even so, the EPA monitors these toxins and, on occasion, research findings may lead to greater regulation. If you are concerned about the safety of your water, have it tested by a commercial laboratory. Or contact your state or local department of health or environmental management, or the EPA for more information about water and air pollution.

The low levels of insecticides and herbicides used to protect the nation's food supply are usually considered safe. Most researchers apply a risk/benefit analysis to the issue of fruit and vegetable contamination. Toxins and pollutants may pose a small risk, but this risk is more than offset by the benefits of keeping foods safe from insects, fungus, and other contaminants, and making these foods widely available to provide the nutrients and cancer fighting substances such foods supply. If you are concerned, you can buy organic fruits and vegetables, but there is, as yet, no real evidence that this will help reduce cancer risk. Certainly, it is prudent to wash all fruits and vegetables thoroughly to remove any pesticide residues. You can also minimize your use of herbicides and insecticides at home, and if you must use such products, follow the instructions carefully.

Many of the toxic chemicals found in waste dumps can be carcinogenic at high levels, although the amounts people are exposed to in their communities are usually very low. The cleanup of such sites is important for the protection of the people living near them.

Last updated:	May 01, 2008