Many parents already worry about the chemicals in the personal care products that their kids use but now a new study takes that fear to the next level: the exposure starts even before a child is born.
Girls exposed to chemicals commonly found in shampoo, toothpaste and soap may hit puberty earlier, even if their only exposure is through the products their mothers used while they were pregnant, according to a new longitudinal study led by researchers at UC Berkeley.
“We know that some of the things we put on our bodies are getting into our bodies, either because they pass through the skin or we breathe them in or we inadvertently ingest them,” said Kim Harley, lead author of the study and associate adjunct professor in the School of Public Health at Berkeley, in the UC newsletter. “We need to know how these chemicals are affecting our health.”
Published in the journal Human Reproduction, this new report comes from data collected as part of the Centre for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study. That project followed 338 children from before birth into adolescence to reveal how early environmental exposures may impact childhood development.
Over the past 20 years, research has shown that girls, and possibly also boys, have been going through puberty earlier and earlier. This is troubling news because scientists have linked the early onset of puberty with greater risk of mental illness, breast and ovarian cancer in girls and testicular cancer in boys.
Early puberty, also known as precocious puberty, is defined as developing breasts and starting periods before the age of eight. The average age for girls is 11. Starting before the age of eight also causes social trouble for young girls, including a heightened tendency towards risky behaviour, explains Harley.
The chemicals in question — phthalates, parabens and phenols — are known as endocrine disrupters, which may mimic hormones and lead children to mature well before their natural time. As the study noted, exposure to these chemicals is widespread, which is why it’s crucial parents be made aware of the findings.
“While more research is needed, people should be aware that there are chemicals in personal care products that may be disrupting the hormones in our bodies,” Harley said, as the UC newsletter noted.
Researchers first noticed the earlier onset of puberty in the late 1990s, and recent studies confirm the mysterious public health trend. A 2012 analysis by the U.S. Centers for Disease Control and Prevention (CDC) found that American girls exposed to high levels of common household chemicals had their first periods seven months earlier than those with lower exposures.
“This study adds to the growing body of scientific research that exposure to environmental chemicals may be associated with early puberty,” says Danielle Buttke, a researcher at CDC and lead author on the study. Buttke found that the age when a girl has her first period (menarche) has fallen over the past century from an average of age 16-17 to age 12-13.
Earlier puberty isn’t just for girls. In 2012 researchers from the American Academy of Pediatrics (AAP) surveyed data on 4,100 boys from 144 pediatric practices in 41 states and found a similar trend: American boys are reaching puberty six months to two years earlier than just a few decades ago. African-American boys are starting the earliest, at around age nine, while Caucasian and Hispanics start on average at age 10.
Some evidence suggests that “hormone disrupting” chemicals may also trigger changes prematurely. Public health advocates have been concerned, for example, about the omnipresence of Bisphenol A (BPA), a synthetic chemical in some plastics, because it is thought to “mimic” estrogen in the body and in some cases contribute to or cause health problems. BPA is being phased out of many consumer items, but hundreds of other potentially hormone disrupting chemicals are still in widespread use.
Dichlorobenzene, used in some mothballs and in solid blocks of toilet bowl and air deodorizers, is also a key suspect in triggering early puberty. It is already classified as a possible human carcinogen, and studies have linked prenatal exposure to it with low birth weight in boys. The U.S. Environmental Protection Agency (EPA) has recently made screening Dichlorobenzene for hormonal effects a priority.
Parents can take steps to reduce our kids’ so-called “toxic burden”: Buy organic produce, hormone- and antibiotic-free meat and dairy and all-natural household cleaners. And keep the dialogue going about healthy food and lifestyle habits so kids learn how to make responsible, healthy choices for themselves.
James E Windsor, Overpasses News Desk
December 22nd, 2018