Reducing Exposures to Reverse Rates of Chronic Disease
 |
|
|
|
|
|
|
|
|
|
|
Cancer and the Environment
Chronicling the Environmental & Occupational Causes of Cancer
Just released in November 2007--"Environmental and Occupational Causes of Cancer: New Evidence, 2005-2007"--a review of the current state of the science on environmental and occupational contributions to cancer.
This update builds upon a 2005 study that reviewed 30 years of scientific evidence, “Environmental and Occupational Causes of Cancer: A Review of the Recent Scientific Literature.”
The reports demonstrate why environmental and occupational cancers should be given serious consideration by policymakers, individuals, and institutions concerned with cancer prevention. Lowell Center researchers critiqued seminal papers that estimate the proportion of cancer to particular factors, examined recent cancer statistics and trends, and reviewed the scientific literature.
EXECUTIVE SUMMARY
Environmental and Occupational Causes of Cancer: New Evidence, 2005-2007
What do we currently know about the occupational and environmental causes of cancer? As of 2007, the International Agency for Research on Cancer has identified 415 known or suspected carcinogens. Cancer arises through an extremely complicated web of multiple causes. We will likely never know the full range of agents or combinations of agents that cause cancer.
However, we do know that preventing exposure to individual carcinogens prevents the disease. Declines in cancer rates – such as the drop in male lung cancer cases from the reduction in tobacco smoking or the drop in bladder cancer among cohorts of dye workers from the elimination of exposure to specific aromatic amines – provides evidence that preventing cancer is possible when we act on what we know. Although the overall age-adjusted cancer incidence rates in the U.S. among both men and women have declined in the last decade, rates of several types of cancers are on the rise; some of these cancers are linked to environmental and occupational exposures.
This report chronicles the most recent epidemiological evidence linking occupational and environmental exposures with cancer. Peer-reviewed scientific studies published from January 2005-June 2007 were reviewed, supplementing our state-of-the-evidence report published in September 2005. Despite weaknesses in some individual studies, we consider the evidence linking the increased risk of several types of cancer with specific exposures somewhat strengthened by recent publications, among them:
- brain cancer from exposure to non-ionizing radiation, particularly radiofrequency fields emitted by mobile telephones;
- breast cancer from exposure to the pesticide dichloro-diphenyl-trichloroethane (DDT) prior to puberty;
- leukemia from exposure to 1,3-butadiene;
- lung cancer from exposure to air pollution;
- non-Hodgkin’s lymphoma (NHL) from exposure to pesticides and solvents;
- prostate cancer from exposure to pesticides, polyaromatic hydrocarbons (PAHs), and metal working fluids or mineral oils.
In addition to NHL and prostate cancer, early findings from the Agricultural Health Study suggest that several additional cancers may be linked to a variety of pesticides.
Our report also briefly describes the toxicological evidence related to the carcinogenic effect of specific chemicals and mechanisms that are difficult to study in humans, namely exposures to bis-phenol A and epigenetic, trans-generational effects. To underscore the multi-factorial, multi-stage nature of cancer, we also present a technical description of cancer causation summarizing current knowledge in molecular biology.
We argue for a new cancer prevention paradigm, one that is based on an understanding that cancer is ultimately caused by multiple interacting factors rather than a paradigm based on dubious attributable fractions. This new cancer prevention paradigm demands that we limit exposures to avoidable environmental and occupational carcinogens in combination with additional important risk factors such as diet and lifestyle.
The research literature related to environmental and occupational causes of cancer is constantly growing and future updates will be carried out in light of new biological understanding of the mechanisms and new methods for studying exposures in human populations. However, the current state of knowledge is sufficient to compel us to act on what we know. We repeat the call of ecologist Sandra Steingraber, “From the right to know and the duty to inquire flows the obligation to act.”
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
