by Laurie Tarkan

When Canada declared bisphenol-A, a chemical widely used in baby bottles, water bottles and canned food, toxic to fetuses and children, it finally brought some credibility to what environmentalists, public health advocates and many reproductive endocrinologists have been warning against for some time. Even better, the United States National Toxicology Program declared that we should be concerned about bisphenol-A in a draft report. "The possibility that bisphenol-A may alter human development cannot be dismissed," wrote the authors of the draft. That's a subtle, but huge admission. Bisphonol-A is a chemical, a hormone-disrupting chemical, that is present in over 90 percent of Americans.

There's more: the leading journal on reproduction, Fertility and Sterility, recently published the proceedings of the Summit on Environmental Challenges to Reproductive Health and Fertility, a gathering of 400 leaders in the field. The report states that exposures to chemicals during critical windows of development and vulnerability may result in impaired development and function of the reproductive tract and reduced fertility, as well as other illnesses, not only for the developing children, but for that child's progeny -- your future grandchildren. There is already evidence that this intergenerational effect is taking place.

The preponderance of the evidence on the harmful effects of hormone-disrupting chemicals stems from studies and observations of the animal world. In the 1990s, studies began to consistently link hormone-disrupting pollutants with reduced fertility in fish, amphibians, reptiles and birds. These associations are strong and well-documented.

Among humans, we are witnessing a number of disturbing trends in fertility. There has been a worldwide increase in the number of men with low sperm counts as well as a 1 percent reduction of testosterone in men per year for the past 40 to 50 years. In women, there have been declines in the age that breast development occurs and that girls experience their first period. There has also been a continuous rise in the rate of endometriosis and polycystic ovarian syndrome, the two most common conditions associated with infertility -- both with strong evidence of links to environmental factors.

Skeptics say there isn't definitive proof that these chemicals have much of an effect on the fertility of humans. The reality is, the sort of evidence they are waiting for would be a devastating tragedy, along the lines of the 2006 movie, Children of Men, a flash forward to the year 2027, when homo sapiens could no longer procreate.

Bisphenol-A is not the only hormone disrupting chemical that people, especially those trying or ever wanting to have children, should try to avoid. Phthalates and parabens are two others found in our everyday products. But there are also the chemicals used in pesticides, herbicides, insecticides, and flame retardants. Of course, getting these chemicals out of the environment would go a long way to reducing exposure through food and water, but there are several steps anyone can take to reduce their exposure now. For couples planning to start a family, the time to make changes is at least three or four months before trying to become pregnant.

First, buy organic foods when you can. They contain less hormone disrupting chemicals. Some hormones used in conventional dairy production can increase your risk of twins or triplets whereas others can interfere with ovulation.

Second, eat less meat. Many chemicals are stored in animal fat. Herbicides and pesticides sprayed on fields become concentrated in fat so that by eating a hamburger, you get that cow's lifetime accumulation of these hormone disruptors.

Third, avoid plastic water bottles with the number 3, 6 or 7 in the "recycle triangle symbol." Instead use glass or stainless, or plastics with the number 1, 2, 4 or 5. Never microwave food in plastics as it causes more of these chemicals to leech out in your meal.

Fourth, examine your cosmetics. Personal care products are a huge source of hormone disrupting chemicals. Nail polish, containing phthalates, is one of the biggest offenders. Look for organic products instead or check out the "Skin Deep" database at the Environmental Working Group's website, www.ewg.org [1], for cleaner alternatives. One chemical-free nail polish line I found on the web is called No-Miss polish.

Fifth, install a reverse osmosis water filter to reduce perchlorates (implicated in thyroid disorders and thyroid cancer), PCB's (associated with endometriosis) and Bisphenol A -- all of which are frequent contaminants of tap water.

Sixth, pay attention to the products you use around your home. Many cleaning products have hormone disrupting properties, and common weed killers have been linked to lower sperm counts. Seek cleaner alternatives now widely available at local stores.

Seventh, start a prenatal vitamin three or four months before you start trying to have a child. The antioxidants help repair and DNA damage that has occurred.

Laurie Tarkan specializes in health reporting and is a regular contributor to the New York Times and national magazines. Look for more fertility-preserving tips in her new book, Perfect Hormone Balance for Fertility [2], co-authored with Dr. Robert Greene, reproductive endocrinologist and hormone expert.
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