Natural News 
Aug 24, 2010
“Endocrine disrupting” chemicals that mimic or interfere with the body’s natural sex hormones are partially responsible for early puberty in girls, according to a study conducted by researchers from Mount Sinai School of Medicine in New York.
“Research has shown that early pubertal development in girls can have adverse social and medical effects, including cancer and diabetes later in life,” researcher Mary Wolff said. “Our research shows a connection between chemicals that girls are exposed to on a daily basis and either delayed or early development.”
The researchers monitored 1,151 U.S. girls between the ages of six and eight for up to two years, regularly measuring the levels of phthalates, phenols and phytoestrogens  in their urine. They found that some of the chemicals  appeared to delay puberty , while others appeared to hasten it. The strongest effect was seen from chemicals classified as phthalates  or phytoestrogens.
Phthalates are a class of chemicals widely used to make cosmetics , adhesives, detergents, packaging, paints and inks, food and pharmaceutical products, and soft plastics  for everything from medical equipment to toys and sex toys. Although the European Union has banned their use in cosmetics due to health  concerns, they are still legal in the United States.
Phenols are industrial chemicals, and include the infamous plastics hardener Bishphenol-A (BPA ). BPA is also used to make linings for food cans.
Phytoestrogens are naturally occurring plant compounds that mimic the action of the hormone estrogen  in the body.
“We believe that there are certain periods of vulnerability in the development of the mammary gland, and exposure to these chemicals may influence breast cancer  risk in adulthood,” Wolff said.
The onset of puberty in girls in Western countries has dropped by a year in the past generation. Western girls now begin menstruating at the average age of 10 years and three months. Most of this drop has been attributed to increased caloric intake and lower activity levels, but scientists are increasingly suggesting that pollution may also be playing a role.
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