Female Troubles

A New York Times special section on women's health last year had 30 pages of articles covering everything from sex, hair loss, mammograms and plastic surgery, to the alleged dangers of exposure to loud music in health clubs. Any connection between women's health and environmental exposures to toxic chemicals went unremarked.

Yet a growing body of evidence suggests that a broad range of women's health problems now on the rise -- as well as problems passed on to our children -- may very well be linked to exposure to synthetic chemicals in the environment, including everyday household products. "Researchers are looking at all of this because there's been an apparent increase in breast cancer and other types of reproductive cancers and dysfunctions," says Bill Suk, director of the office of program development at the National Institute of Environmental Health Sciences (NIEHS), which is overseeing a number of studies. Many of the studies are probing links between various disorders and endocrine-disrupting chemicals (EDCs), substances that essentially mimic, block or otherwise interfere with estrogen, testosterone or thyroid hormone (see "Hand-Me-Down Poisons" in The Green Guide #42). NIEHS is prioritizing research on how environmental chemicals may play a part in autoimmune disorders, the growing incidence of breast, endometrial and ovarian cancers, infertility, and other reproductive disorders such as premature menstruation and premature menopause.

While Suk cautions that "there are many things operating here that we don't yet fully understand," he adds, "we're finding some pretty alarming phenomena. Fertility is down, male sperm count is down, kids are undergoing puberty early, and there's a chance of some potentially significant transgenerational effects as fetuses and young infants are exposed." Among the environmental estrogens being studied are pesticides and industrial compounds such as DDT and PCBs, and plastic-related chemicals. Natural plant estrogens in our diet are also being studied; unlike synthetic estrogens and other EDCs, plant estrogens are rapidly broken down by the body into harmless substances and may actually be beneficial. Studies show women on soy-based diets have reduced rates of breast cancer.

Women's environmental health is a huge new field of research. Since 1994, the Federal Interagency Working Group on Women's Health and the Environment has seen "a 50% increase in the number of studies, policies, services, and training just on women and the environment," says Suzanne Haynes, assistant director for science in the Office of Women's Health at the U.S. Public Health Service. New federal studies cover everything from examining the effects of pesticides on women farmworkers, to the effect of indoor pollution on the average homemaker. Haynes quipped, "If it could only prove women should stop doing housework!"

Hazardous Work

Most data until now has come from industrial workplace rather than household exposures. A large body of evidence suggests a strong link between high doses of toxic chemicals and reproductive cancers and disorders in men and women workers. Risky jobs include manufacturing, painting and varnishing, petroleum refining, electronics and plastics production. A 1993 position paper by the American College of Occupation-al and Environmental Medicine (ACOEM) stated that the women's health problems of greatest concern in terms of their "prevalence and severity" were reproductive effects of workplace exposures. The ACOEM board found that "the entire reproductive cycle may be at risk for exposures to physical and chemical agents in the workplace," naming infertility, spontaneous abortion, birth defects, hereditary diseases, and cancer as major issues.

What is new is the discovery that human beings -- and women and children particularly -- may be more vulnerable to chemicals at smaller doses than previously thought, and of the sort encountered in our homes and food rather than just on the job. Depending on when a woman is exposed during hormonal cycles, she could be more susceptible than usual to carcinogens, neurotoxins and hormone disrupting chemicals. A developing fetus or young infant could be vulnerable at much lower levels (see "Hormonal Imbalance" in The Green Guide #54/55).

ACOEM's paper noted that an "increased rate of spontaneous abortion in the semiconductor industry has been established -- probably due to exposure to glycol ethers and other solvents." Glycol ethers were phased out by the industry in response to a 1992 study that found a 40% increase in miscarriage rates among semiconductor chip workers. However, there are about 500 to 1,000 chemicals in use on average per plant, according to an October 5, 1998 front-page article in The Wall Street Journal. These include the known carcinogens arsenic, benzene and chromium. Now new studies are going forward of female workers exposed to chemical fumes at National Semiconductor's computer chip plant in Greenock, Scotland, who say their uterine and breast cancers and birth defects are clearly a result of their exposure. In the U.S., IBM is being sued by former chip workers in East Fishkill, New York; Burlington, Vermont; and San Jose, California.

Gender & Health

There are definitely sex-related differences in how the body reacts to toxic chemicals. For example, according to Frederica Perera, Dr.P.H., at Columbia University School of Public Health, women smokers are up to three times more likely to contract lung cancer than men. But, until now, most of what we know about the health impact of chemical exposure comes from studies on healthy male workers, reported Jeffrey Lybarger, M.D., at the 1998 Women's Health and the Environment conference in Washington, D.C. Looking at low-level, long-term exposures of the general population from waste sites, an increased incidence rate for breast, cervical and uterine cancers was indicated in preliminary results from an ongoing National Exposures Registry study. Exposures to trichloroethylene (TCE), benzene and dioxin are also being tracked.

Researchers are also trying to discover why women have a disproportionately higher incidence than men of autoimmune diseases like lupus, the topic of a study by Glinda Cooper, Ph.D., an epidemiologist at NIEHS. Recent studies have linked silica, found in scouring powder, to autoimmune disease, specifically systemic lupus erythematosis (SLE). "We think that high hormonal activity is playing a role, but we don't yet know to what extent -- if any -- environmental chemicals play a part. This is a focus that needs to be studied," Cooper says.

NIEHS is also investigating the roles of environmental estrogens and genetic factors in uterine fibroids and endometriosis, a condition in which tissue normally located inside the uterus migrates outside. Both disorders are implicated in infertility, which affected some 6.1 million women of reproductive age in the U.S. in 1995. (See "Shrinking Fibroids Naturally" in this issue)

In an ongoing study focused on endometriosis, University of California researcher Brenda Eskenazi, Ph.D., is looking at women exposed to dioxin after a 1976 chemical plant explosion in Seveso, Italy released trichlorophenol. Another researcher, Sherry Rier, Ph.D., of Dartmouth Medical School, found the disease in 71% of monkeys fed dioxins (25 parts per trillion), compared to 33% in the control group, in a study published in Fundamental and Applied Toxicology in 1993.

Although the research is moving forward, we may never come up with definitive answers about the effects of pollution on "female troubles." But, "The good news is that there are things you can do," says Maria Valenti, co-author of "Generations at Risk," a 1996 report by the Greater Boston Physicians for Social Responsibility. "People just don't think about what they're being exposed to. In the home environment, there are paints and thinners, cleaning products and pesticides with potentially dangerous ingredients. Then there are fumes from dry cleaning solvents and formaldehyde in building materials," she warns.

Why wait? By making environmentally sound, least-toxic product choices while limiting our exposures in food, water and airborne hazards, we can make a positive difference in our health and that of our children.

Francesca Lyman writes the biweekly "Your Environment" column for MSNBC.com