Shanna Swan was at the EU Parliament on 12 April 2012 to present EU decision makers with her latest research findings on the health impacts of endocrine disrupting chemicals (EDCs), a trip sponsored by the Health and Environment Alliance (HEAL). Go to http://www.env-health.org/news/latest-news/article/us-expert-warns-on-feminisation-of
Old Order Mennonites adhere to a simpler lifestyle. They eat mostly fresh unprocessed foods, farm without pesticides, and use personal care products sparingly, if at all, and no cosmetics. For transportation they predominantly use bicycles and a horse and buggy. These practices made us think that they would experience lower exposures to endocrine disrupting chemicals, including bisphenol A and several phthalates. Therefore, we studied a small group of pregnant women from this community and measured amounts of several of these chemicals. Over all levels were lower than those measured in the general public, and some were much lower. We conclude that this study, though small, reveals important messages about how to avoid or reduce our exposure to potentially harmful chemicals.
Fetal exposure to antiandrogens alters androgen-sensitive development in male rodents, resulting in less male-typical behavior. Fetal phthalate exposure is also associated with male reproductive development in humans, but neurodevelopmental outcomes have seldom been examined in relation to phthalate exposure. To assess play behavior in relation to phthalate metabolite concentration in prenatal urine samples, we recontacted participants in the Study for Future Families whose phthalate metabolites had been measured in mid-pregnancy urine samples. Mothers completed a questionnaire including the Preschool Activities Inventory (PSAI), a validated instrument used to assess sexually dimorphic play behavior. We examined play behavior scores (masculine, feminine and composite) in relation to (log10) phthalate metabolite concentrations in mother’s urine separately for boys (N=74) and girls (N=71). Covariates (child’s age, mother’s age and education and parental attitude towards atypical play choices) were controlled using multivariate regression models. Concentrations of dibutyl phthalate (DBP) metabolites, mono-n-butyl phthalate (MnBP) and mono-isobutyl phthalate (MiBP), and their sum, were associated with a decreased (less masculine) composite score in boys (regression coefficients -4.53, -3.61, and -4.20, p=0.01, 0.07 and 0.04 for MnBP, MiBP and their sum, respectively). Concentrations of two urinary metabolites of di(2-ethylhexyl) phthalate (DEHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) and mono (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and the sum of these DEHP metabolites plus mono(2-ethylhexyl) phthalate were associated with a decreased masculine score (regression coefficients -3.29, -2.94, and -3.18, p=0.02, 0.04 and 0.04) for MEHHP, MEOHP, and the sum, respectively. No strong associations were seen between behavior and urinary concentrations of any other phthalate metabolites in boys, or between girls’ scores and any metabolites. These data, though based on a small sample, suggest that prenatal exposure to antiandrogenic phthalates may be associated with less male-typical play behavior in boys. Our findings suggest that these ubiquitous environmental chemicals have the potential to alter androgen-responsive brain development in humans.
USA Today article on effects of endocrine disruptors:
By Liz Szabo, USA TODAYBaby boys are more likely to have changes in their genitals — such as undescended testicles and smaller penises — if their mothers were exposed to high levels of a controversial chemical during pregnancy, a new study shows.
Virtually everyone has been exposed to the chemicals, called phthalates, which are used in countless plastic products and are found in everything from drinking water to breast milk to household dust, according to the study, published in the current issue of Environmental Research.
Until recently, most studies have been conducted in animals. Those tests suggest that phthalates interfere with the male sex hormone testosterone, causing a “phthalate syndrome” in male fetuses that changes the way their genitals develop, says study author Shanna Swan, a professor at the University of Rochester School of Medicine and Dentistry.
Swan says her study of 106 mothers and sons suggests this syndrome may be occurring in humans, too.
In her study, doctors measured phthalate levels in the mothers’ urine during pregnancy, then examined the babies at 12 months.
Boys whose mothers had the highest phthalate levels were more likely than others to show three anatomic differences: smaller penises, a shorter distance between the anus and base of the penis, and undescended or incompletely descended testicles, Swan says.
Swan also notes that most boys had normal sex organs. Twelve had incompletely descended testicles, while 29 babies fell into a category with “shorter” anogenital distances.
In most cases, these aren’t serious problems, Swan says. Babies with undescended testicles often need no treatment, because the organs descend on their own by age 1. Others can be helped with hormone treatments or surgery. And even the smaller penises appeared to be within the normal range.
But Swan says she’s concerned that these changes indicate a deeper problem — that phthalates may have made the boys “less masculine” in key ways. In animals, males with these genital changes also had lower sperm counts, she says.
Swan says she is also concerned about girls. It’s possible that any effects from pre-birth phthalate exposure may not surface until the girls hit puberty or try to have children, she says.
In her paper, she notes that other researchers have linked phthalates to reduced sperm quality and DNA damage, as well as hormone changes, reduced lung function and premature puberty.
More and more Americans are becoming concerned about phthalates.
In August, Congress banned several types of the chemicals in children’s toys and products. Dozens of hospitals around the country are phasing phthalates out of their neonatal intensive care units to protect vulnerable newborns, who may spend weeks or months connected to plastic tubing.