Breast Cancer and Dioxins

Evidence has been mounting that man-made chemicals may be the underlying cause of many cases of breast cancer. Once ingested, these synthetic compounds mimic the action of estrogen long considered to be a risk factor for breast cancer and throw the hormone system into chaos. A woman's earliest and most dangerous contact with them may be in the womb.

Such "estrogenic" chemicals have already been associated with the increase in reproductive abnormalities in males, including cancer of the testes and prostate. They are found in fertilizers, pesticides, industrial effluent, some modern products, car exhaust and even water, soil and air. They also leach out of many of the plastics used to package food.

Dioxin, PCBs, DDT and other hormone-disrupting estrogenics are difficult to get rid of because they are "lipophilic" (stored in body fat). Consequently, they accumulate up the food chain so that the species at the top humans have higher levels.

Several factors lead scientists to conclude that estrogenic or other hormone-disrupting chemicals play a role in breast cancer. First, breast cells are designed to respond to estrogen. Estrogen receptors in breast tissue are just waiting for estrogens to set off changes to prepare the body for reproduction and pregnancy.

It is widely accepted that a woman's lifetime exposure to estrogen is an important risk factor for breast cancer. The longer the exposure, the greater the risk. Synthetic estrogenic chemicals enter the body before birth. Starting your period earlier or experiencing a later menopause can increase the time exposed to estrogen.

Lab tests show that some breast cancer cells will only grow in the presence of estrogen. In these tests, the blocking or removal of estrogen halts the growth of such cancers.

Over the same time scale that these hormone-disrupting chemicals have become widespread environmental contaminants, there has been a startling rise in breast cancer. Fifty years ago, one woman in 22 would get breast cancer in her lifetime. The risk is now as high as one in eight.

Women with the highest levels of DDT in their blood were shown to be four times as likely to contract breast cancer as women with lower levels. A number of research studies confirm this result. A study conducted by professor Mary Wolff at the Mount Sinai School of Medicine in New York compared breast cancer patients with women whose biopsies showed benign results; the breast cancer patients had 50-percent higher levels of DDE, DDT and chlorinated PCBs compared with the control group!

"It's been suggested that the levels of synthetic estrogens are too low to make a difference, compared to naturally-occurring estrogens in our bodies," says Wolff. "It's important to realize that these chemicals are not metabolized very easily. They stick around in the body for a long time and therefore can have a repeated effect."

Avoiding these chemicals is difficult, but reducing hydrogenated fats is a good start. Fat is the point of accumulation for these estrogens. Also, a lot but not all plastic packaging is a danger. Because the government does not require labelling, it's best to avoid as much plastic as you can. Pesticides containing estrogens cannot always be washed off (they are not necessarily water-soluble) and sometimes are systemic, meaning they penetrate inside the product. Imported foods may contain pesticides that are banned in this country. If you buy bottled water, the plastic jug may leach chemicals, but not if it has been cleaned inside with a detergent containing an estrogen.