It seems in the middle of the previous decade, the dangers associated with Bisphenol A (BPA) and, to a lesser extent, phthalates entered into the general consciousness of most Americans. We learned just how pervasive these hormone-mimicking chemicals were in a range of products we relied upon for our convenient lifestyles.
Many people, upon learning of the side effects associated with toxic levels of these “endocrine disruptors,” discarded products like baby bottles, lotions, powders and shampoos in the hopes they could avoid or reverse any damage.
The reason these chemicals earned the moniker of endocrine disruptors had everything to do with the fact they are able to mimic the body’s natural hormones. In laboratory animal tests, excess of these chemicals had been shown to cause reproductive and neurological damage.
So dangerous are these substances that in 2009 the Endocrine Society, a medical group, issued a statement decrying the use of these chemicals for products intended for general public consumption. They believed BPA and phthalates, along with pesticides and other common chemicals, represented a “significant concern for public health” and should, at all costs, be avoided. In their statement, they claimed:
“Although more experiments are being performed to find the hows and whys, what should be done to protect humans? The key to minimizing morbidity is preventing the disorders in the first place. However, recommendations for prevention are difficult to make because exposure to one chemical at a given time rarely reflects the current exposure history or ongoing risks of humans during development or at other life stages, and we usually do not know what exposures an individual has had in utero or in other life stages.
“In the absence of direct information regarding cause and effect, the precautionary principle is critical to enhancing reproductive and endocrine health. As endocrinologists, we suggest that The Endocrine Society actively engages in lobbying for regulation seeking to decrease human exposure to the many endocrine-disrupting agents. Scientific societies should also partner to pool their intellectual resources and to increase the ranks of experts with knowledge about endocrine disrupting chemicals who can communicate to other researchers, clinicians, community advocates, and politicians.”
The recommendation to avoid exposure to these chemicals, according to a recent study, may be far more difficult than simply removing the products from your house. According to lead author of the study, Dr. Sheela Sathyanarayana, “Current information we give families may not be enough to reduce exposures.” In addition to being the lead author of the study entitled “Unexpected Results in a Randomized Dietary Trial to Reduce Phthalate and Bisphenol A Exposures”, Sathyanarayana is also an environmental health pediatrician in theUniversity of Washington School of Public Health and at Seattle Children’s Research Institute. She is also an assistant professor of pediatrics at the UW School of Medicine and an attending physician at Harborview Medical Center’s Pediatric Environmental Health Specialty Unit.
The study, published today in the Nature Journal of Exposure Science and Environmental Epidemiology, addresses how people may be unable to escape exposure to these chemicals as they are appearing in their diets, even when their individual meals were organic in nature and the foods were prepared, cooked and stored in non-plastic containers. The study also reinforces the notion that the most vulnerable population continues to be children.
It was in previous studies a link was established between prenatal exposure to phthalates and abnormalities in the male reproductive system. Additionally, associations were recognized between fetal exposure to BPA and hyperactivity, anxiety and depression in girls.
The research team, comprised of Garry Alcedo of the Seattle Children’s Research Institute, Brian E. Saelens and Chuan Zhou of the UW Department of Pediatrics, Russell L. Dills and Jianbo Yu of the UW Department of Environmental and Occupational Health Sciences, and Bruce Lanphear of the British Columbia Children’s Hospital and Simon Fraser University in Canada, compared the chemical exposures of 10 families for their study.
One half of the participating families were given written instructions on how to effectively reduce their exposure to phthalate and BPA. The instructions given the families were handouts composed by the national Pediatric Environmental Health Specialty Units. These public health units are comprised of experts on environmentally related health effects in children.
The other half of the study participants were provided with local, fresh, organic food catered in for them. At no point in the preparation, cooking or storage of the food were plastic containers used.
Funding for the study was provided through the Center for Ecogenetics and Environmental Health located in the Department of Environmental and Occupational Health Sciences in the UW School of Public Health. There was also grant funding provided by the National Institute of Environmental Health.
Despite the care taken to provide a segregated diet for the families who received the catered foods, the research team was quite surprised after they tested for the urinary concentrations of metabolites for phthalates and BPA. The expectation for the team was the levels of the metabolites would decrease in both the adults and children in these families.
What they found was the complete opposite. The urinary concentrations for phthalates were 100-fold higher than what is typically found in the majority of the general population. The team was able to make this comparison thanks to previous study conducted by the National Health and Nutrition Examination Survey. This program is, itself, funded and operated by the Centers for Disease Control and Prevention and is designed to assess the health and nutritional status of both adults and children in the United States. In the comparison, they found children in their participant families presented extremely elevated concentrations in their urine.
From here, the researchers then tested the phthalate concentrations in the individual food ingredients that were used in the catered diets. What they found was alarming. Dairy products, like butter, cream, milk and cheese, had concentrations above 440 nanograms/gram. Seasonings like cinnamon and cayenne pepper had concentrations above 700 ng/g. But it was ground coriander, with concentrations over 21,400 ng/g, that was particularly shocking.
“We were extremely surprised to see these results. We expected the concentrations to decrease significantly for the kids and parents in the catered diet group. Chemical contamination of foods can lead to concentrations higher than deemed safe by the US Environmental Protection Agency,” said Sathyanarayana.
The study results allowed the researchers to formulate estimates that an average child, between the ages of three and six years, are typically exposed to 183 milligrams per kilogram of their body weight each day. According to the EPA, the recommended limit is no more than 20 mg/kg/day.
“It’s difficult to control your exposure to these chemicals, even when you try,” said Sathyanarayana. “We have very little control over what’s in our food, including contaminants. Families can focus on buying fresh fruits and vegetables, foods that are not canned and are low in fat, but it may take new federal regulations to reduce exposures to these chemicals.
Source: Alan McStravick for redOrbit.com – Your Universe Online
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