Dr Linda Giudice has treated thousands of patients over the years with a range of troubling reproductive disorders, and this week, she joined health experts and a young mother in fingering chemicals as the probable cause.
"I have treated thousands of patients... including young men with very abnormal sperm counts or a history of testicular cancer, women as young as 17 and already in the menopause, little girls with the onset of puberty at six or eight," Giudice told a news conference.
"There is increasing evidence that environmental contaminants may be playing a role in these disorders," said Giudice, who chairs the department of obstetrics, gynecology and reproductive sciences at the University of California, San Francisco.
Molly Gray, a young mother who was found to have high levels of toxic chemicals in her blood during her pregnancy, suspects chemicals were the culprit.
She recalled how, after several miscarriages, she radically changed her lifestyle and ate only organically grown food, avoided fish high in mercury, shunned plastic food storage containers, and switched to "green" cleaning products.
But in spite of the changes, tests on Gray during her pregnancy showed she had high levels of 13 toxic chemicals in her blood.
"These chemicals have become ubiquitous in the environment and, as clean as I tried to be, it was not enough to protect my baby boy," she said.
"I was disheartened. I felt helpless," she said.
Gray and Giudice this week joined Tracey Woodruff, director of UCSF's program on reproductive health and the environment, and Andy Igrejas, campaign director for the Safer Chemicals, Healthy Families advocacy group, in calling for the 1976 law that regulates chemicals in the United States to be overhauled.
According to Safer Chemicals, Healthy Families, the 34-year-old Toxic Substances Control Act (TSCA) has failed to regulate chemicals in consumer products, including chemicals with proven links to cancer, learning disabilities, asthma, reproductive disorders and other health problems.
The law has not evolved with chemical exposure, which since World War II has increased more than twenty-fold, said Giudice.
"Today there is ubiquitous exposure to environmental contaminants through air, water, food, drink, cosmetics, personal care products, pesticides, herbicides and everyday household items," she said.
Even the flame retardants used in furniture contain potentially harmful chemicals, said Woodruff.
"We have begun to question whether exposure to these are affecting our reproductive health," she said.
A massive study released in August that showed US girls are starting puberty earlier than they were just 10 years ago singled out endocrine disruptor chemicals as one of the likely culprits of early onset puberty, said Woodruff.
An overwhelming majority of the girls in the study who developed breasts and started their menstrual cycles as young as age seven had high levels of flame retardant and other chemicals in their bodies.
Some of the chemicals were banned decades ago but "remain in the food chain," said Woodruff. Others are commonly found in household cleaners and other items that people come into contact with every day.
Other studies have linked exposure to chemicals with illnesses ranging from asthma to cardiovascular disease and cancer.
A study published in September in the Archives of Pediatric and Adolescent Medicine, a journal of the American Medical Association, found a link between chemicals used to make non-stick cookware and higher blood cholesterol levels in children.
And a group of experts said at a major science meeting held in February this year that they suspected a link between the rising incidence of breast cancer and exposure to chemicals.
Yet, in the 34 years since the TSCA was enacted, just five chemicals have been regulated under the law.
Bills to overhaul the TSCA were introduced in Congress this year but never taken up, said Igrejas.
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