Are environmental estrogens a real problem for your child?

Depending on what you read, xenoestrogens are either causing a major health epidemic among our children, or they are a scare tactic used by political and health activists to make parents worry needlessly.

Xenoestrogens are defined as environmental estrogens, or chemicals that can mimic the effect of estrogen in the body. Estrogen is the main female sex hormone and is responsible for the development of secondary sexual characteristics in girls, including development of breasts, a higher-pitched voice, and other signs of maturity. By exposing our children to high levels of xenoestrogens, some people worry that we are causing premature development in girls and the development of female characteristics in boys, such as breast tissue and delayed male puberty.

Common sources of xenoestrogens include pesticides, plastics such as Bisphenol A (BPA), certain food additives, and soy-based products (soy contains a chemical that is a known xenoestrogen).

The US Food and Drug Administration (FDA) recommends that parents limit their children’s exposure to BPA, based on studies which indicated estrogen-like effects on animal models. In the US, BPA is banned in baby bottles and sippy cups, although it is still used in some infant formula containers. Knowing this can be helpful in putting a parent’s mind at ease, but it doesn’t address the larger question of environmental estrogens or the fact that BPA is still widely used in plastic drinking containers.

In fact, the science surrounding xenoestrogens and children is still murky. Findings from a few recent studies include:

• Many processed foods have high levels of soy-based ingredients, which are highly estrogenic, but it’s impossible to measure for any long-term effects.
• No long-term speech or learning effects of fetal xenoestrogen exposure were observed among boys in one study, although another study found that boys who were exposed to high levels of xenoestrogens had possibly increased birth weight and a higher risk of obesity later in life.
• Some studies have found that xenoestrogen exposure is at least partly responsible for early puberty and breast development among girls, while others have been less definitive. In boys, a handful of studies have found that exposure to high levels of xenoestrogens delays puberty—but because puberty is so complex, it’s hard to definitively blame environmental estrogens and other hormone-like chemicals.

Overall, most researchers note that these chemicals are nearly impossible to avoid in modern life—they are present in our food, water, and many of our products.

The researchers studying this are careful not to draw any long-term conclusions, partly because widespread exposure to these chemicals is so recent, and partly because the hormone system and sexual maturation is so complex it can be nearly impossible to tease out one single cause. For example, many researchers believe that “normal” early puberty is due to improved nutrition across the world, so it doesn’t make sense to compare today’s kids to earlier children who lacked access to adequate food and nutrients.

This type of ambiguity is normal in the research world, but it can be confusing for well-meaning parents. For now, the American Academy of Pediatrics (AAP) recommends avoiding all plastics unless clearly marked “BPA-free.”