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Articles on Breast Health

More Than 200 Chemicals Linked to Breast Cancer!

Here it is: Validation of what we have been saying for many years now.

According to an article published in the Journal, Cancer, more than 200 chemicals -- many found in urban air and everyday consumer products -- caused breast cancer in animal tests. Breast cancer is the leading killer of women in the United States.

The researchers, who hailed from five different institutions, concluded that reducing exposure to the compounds could prevent many women from developing the disease.

Experts say that family history and genes are responsible for a small percentage of breast cancer cases but that environmental or lifestyle factors such as diet are probably involved in the vast majority of breast cancer cases.

The researchers wrote in a special supplement to the journal Cancer, "These compounds are widely detected in human tissues and in environments, such as homes, where women spend time."

The scientists said that, because breast cancer is so common and these chemicals are so widespread, “the public health impacts of reducing exposures would be profound even if the true relative risks are modest," they wrote. "If even a small percentage is due to preventable environmental factors, modifying these factors would spare thousands of women."

The three reports and a commentary were compiled by: Researchers from the Silent Spring Institute, a women's environmental health organization in Newton, Mass.; Harvard's Medical School and School of Public Health in Boston; the Roswell Park Cancer Institute in Buffalo, N.Y.; and USC's Keck School of Medicine.

Reviewing hundreds of existing studies and databases, the team produced what it called "the most comprehensive compilation to date of chemicals identified as mammary carcinogens."

The researchers named 216 chemicals that induce breast tumors in animals. Of those, people are highly exposed to 97. The most commonly encountered chemicals included industrial solvents, pesticides, dyes, gasoline and diesel exhaust compounds, cosmetics ingredients, synthetic hormones, pharmaceuticals, radiation, and a chemical in chlorinated drinking water.

"Almost all of the chemicals were mutagenic, and most caused tumors in multiple organs and species” according to the scientists.
Toxicologists say that other mammals, such as rats and mice, often develop the same tumors as humans do, and that animal tests are efficient means of testing the effects of chemicals. Animal studies generally use high doses of a substance to simulate a lifetime of exposure, and then the results are extrapolated to the lower levels that people are exposed to.

Ana Soto, a Tufts University professor of cell biology who specializes in cellular origins of cancer and effects of hormone- disrupting contaminants, said there probably was a link between breast cancer and exposures to chemicals in the environment. Soto said, “More and more, cancer looks like an environmental disease."

Seventy-three of the chemicals are present in consumer products or are food contaminants -- 1,4-dioxane in shampoos, for example, or acrylamide in French fries. Thirty-five are common air pollutants, 25 are in workplaces where at least 5,000 women are employed, and 10 are food additives, according to the reports.

There are probably many more than 216, the research team said, because only about 1,000 of the 80,000 chemicals registered for use in the United States have been tested on animals to see whether they induce cancerous tumors or mutate DNA. Such tests cost $2 million each.

"… research in the last five years has strengthened the human evidence that environmental pollutants play a role in breast cancer risk," the researchers wrote. They said the existing studies suggested "substantial public health impact."

Human evidence is particularly strong for PCBs, or polychlorinated biphenyls -- compounds widely used in the 1940s to late 1970s that still contaminate fish and other foods -- and for polycyclic aromatic hydrocarbons, or PAHs, found in diesel and gasoline exhaust. Solvents in dry cleaning, aircraft maintenance and other jobs also may increase breast cancer risk.

The scientists conducted the review hoping to lay the groundwork for new human studies, as well as to persuade regulators to use existing animal data to strengthen regulations and require more testing of chemicals.

Researchers Hunt and Soto urged society not to wait for scientific proof to reduce exposure to the chemicals.

Researchers name 216 chemicals that cause breast cancer in animal tests. Here are some of the most widespread:

1,4 dioxane: detergents, shampoos, soaps
1,3 butadiene: vehicle exhaust
Acrylamide: fried foods
Benzene: vehicle exhaust
Styrene: plastics, hobby supplies, adhesives
Vinyl chloride: found in vinyl products
Dichloroethane: paint remover
Toluene diisocyanate: foam cushions
Methylene chloride: furniture polish, fabric cleaners, wood sealants
PAHs: Diesel & gasoline exhaust
Atrazine: herbicides, especially used with corn

"When you look at their list of chemicals, we are exposed to all of it," Soto said. "We know humans are exposed to mixtures, and studying mixtures is very difficult. We will never have the whole picture, and it will take many, many years to collect epidemiological evidence, so we should take some preventive measures now."


These chemicals are xenoestrogens. Natural progesterone can help protect you from their harmful effects. Try to avoid such chemicals as best you can AND use natural progesterone. Natural progesterone opposes the effects of excess estrogen on the body.


  1. Find out the composition of consumer goods you use regularly, including personal-care products and cosmetics. Read labels or call manufacturers and ask about synthetic materials in their products.

  2. Whenever possible, purchase organically grown fruits and vegetables.

  3. Buy meat and dairy products that are hormone-free.

  4. Remove plastic wrap and Styrofoam trays from foods--including deli meats, cheeses, and raw meat--and replace them with wax paper or freezer paper. Slice off cheese surfaces that have been in contact with plastic wrap.

  5. Avoid water, soft drinks, and baby formula sold in polycarbonate (clear plastic) bottles. If possible, use only glass baby bottles. If you use polycarbonate bottles, do not heat or microwave them.

  6. Do not microwave food or water in plastic or Styrofoam containers. Use only ceramic or glass containers. If you need a lid, use a flat dish or a piece of freezer paper. One Dartmouth University Study showed that plastic wrap heated in a microwave oven with vegetable oil had 500,000 times the minimum amount of xenoestrogens needed to stimulate breast cancer cells to grow in the test tube.

  7. Invest in a water filter to separate out xenoestrogens that may be in municipal water supplies.

  8. Use organic pesticides. Avoid having your home sprayed by an exterminator.

  9. Consider taking the carpets out of your children’s bedrooms as many carpet materials contain chemicals.

  10. Avoid toxic paints or glues and even nail polish.

Remember: Birth control pills and synthetic hormones are NOT natural estrogens.

They are foreign to the body. Use natural progesterone and natural estrogen only.

Source:  Los Angeles Times, May 14, 2007