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From USA Today:

“All of our friends told us to cherish every moment,” Claudia says. “When I started planning her first birthday party, I remember crying and wondering where the time had gone.”

Even so, Laila’s parents never expected their baby to hit puberty at age 6.

They first noticed something different when Laila was 3, and she began to produce the sort of body odor normally associated with adults. Three years later, she grew pubic hair. By age 7, Laila was developing breasts.

Without medical treatment, doctors warned, Laila could begin menstruating by age 8 — an age when many kids are still trying to master a two-wheeler. Laila’s parents, from the Los Angeles area, asked USA TODAY not to publish their last name to protect their daughter’s privacy.

Doctors say Laila’s story is increasingly familiar at a time when girls are maturing faster than ever and, for reasons doctors don’t completely understand, hitting puberty younger than any generation in history.

About 15% of American girls now begin puberty by age 7, according to a study of 1,239 girls published last year in Pediatrics. One in 10 white girls begin developing breasts by that age — twice the rate seen in a 1997 study. Among black girls, such as Laila, 23% hit puberty by age 7.

“Over the last 30 years, we’ve shortened the childhood of girls by about a year and a half,” says Sandra Steingraber, author of a 2007 report on early puberty for the Breast Cancer Fund, an advocacy group. “That’s not good.”

Girls are being catapulted into adolescence long before their brains are ready for the change — a phenomenon that poses serious risks to their health, says Marcia Herman-Giddens, an adjunct professor at the University of North Carolina-Chapel Hill.

“This is an issue facing the new generation,” says Laila’s doctor, Pisit “Duke” Pitukcheewanont, a pediatric endocrinologist at Children’s Hospital of Los Angeles, who treats girls with early puberty. “Many parents don’t know what is going on.”

Researchers don’t completely understand why the age of puberty is falling, Herman-Giddens says. Most agree that several forces are at work, from obesity to hormone-like environmental chemicals. There’s no evidence that boys are maturing any earlier, says Paul Kaplowitz, author of Early Puberty in Girls.

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From Chemical & Engineering News:

Two perfluorinated chemicals are linked to a delayed onset of puberty, according to a study of nearly 6,000 children living near a chemical plant (Environ. Sci. Technol., DOI: 10.1021/es1038694).

Since 1951, a DuPont plant near Parkersburg, W. Va., has released perfluorooctanoic acid (PFOA), a surfactant used in Teflon production, into the air and the nearby Ohio River. As a result, people living in the area have abnormally high levels of this compound in their blood.

In 2001, residents of the Mid-Ohio River Valley filed a class-action lawsuit against DuPont, alleging health problems that arose from drinking contaminated water. The company settled the lawsuit and agreed to fund research to determine whether PFOA exposure caused measurable health changes. Scientists had previously shown—in animals only—that PFOA causes cancer and disrupts sexual development.

Tony Fletcher, an epidemiologist at the London School of Hygiene & Tropical Medicine, sits on the scientific advisory panel established by the settlement. He wanted to know if PFOA alters sexual development in humans as it does in animals.

In 2005 and 2006, in research funded by the settlement, health care workers collected blood and medical histories from 69,030 people who lived in contaminated water districts surrounding the chemical plant. Fletcher and his colleagues analyzed data gathered from 3,067 boys and 2,931 girls between the ages of 8 and 18. They found that the median PFOA serum concentration was 26 ng/mL for boys and 20 ng/mL for girls. Both concentrations were much higher than the level in the general U.S. population, 4.2 ng/mL. The researchers also examined serum levels of a related chemical that has also been linked to altered timing of sexual maturation in animals. That chemical is perfluorooctane sulfonate (PFOS), which was not produced by the DuPont plant. The median level of PFOS in the children was only slightly higher than the national average.

To determine the age at which the children reached puberty, the researchers used a questionnaire and measured blood levels of sex hormones. When the investigators compared serum PFOA or PFOS levels with the age of onset of puberty, they found that girls with high concentrations of PFOA started puberty later than girls with low concentrations did. Meanwhile, both boys and girls with high levels of PFOS matured later than their low-concentration peers did. For both chemicals, the median delays in puberty were about 4 to 6 months—a significant change, but one that’s unlikely to cause health problems, Fletcher says.

“These results were surprising because many endocrine disrupters lead to earlier puberty rather than delayed puberty,” he says. Previous studies of the developmental effects of perfluorochemicals have used only small groups of people and produced inconclusive results, Fletcher says. But he hopes that his study, the largest yet to examine the effects of PFOA and PFOS on puberty in humans, will pave the way for studies of other populations exposed to perfluorochemicals early in life.

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