Evidence increasingly links endocrine-disrupting chemicals (EDCs) to diabetes and obesity, among other conditions, according to the second scientific statement to address this issue from the US Endocrine Society.
The new statement builds on the Endocrine Society's landmark 2009 report, which examined the scientific evidence on EDCs and their impact on humans. It was published online September 28.
Unborn children are particularly at risk when exposed to endocrine disrupters, according to the society. Animal studies indicate that exposure to even tiny amounts in the prenatal period can trigger obesity in later years, and some disrupters directly target beta and alpha cells in the pancreas, as well as fat and liver cells. All of this can lead to insulin resistance and type 2 diabetes.
Endocrine disrupters can also alter the way cells grow and develop by mimicking, blocking, or interfering with the body's natural hormones.
Nearly everyone has been exposed to one or more of these chemicals, which include bisphenol A (BPA) found in food-can linings and cash-register receipts, phthalates found in plastics and cosmetics, flame retardants, and pesticides.
Indeed a literature review presented recently at the European Association for the Study of Diabetes (EASD) 2015 Meeting in Stockholm linked exposure to pesticides to a 60% increased risk of type 2 diabetes.
Stronger Evidence in Past 5 Years: Advice for Consumers and Doctors
The new statement corroborates earlier findings, linking endocrine disrupters — in addition to their impact on obesity and diabetes — to effects on male and female reproductive health, hormone-related cancers, prostate conditions, thyroid disorders, and neurodevelopmental issues.
In an online press conference with reporters on Monday, Andrea Gore, PhD, professor and Vacek chair of pharmacology at the University of Texas at Austin, and chair of the task force that developed the statement, said the group is highlighting obesity and diabetes this time because the evidence for effects on these diseases is much stronger than it was 5 years ago.
Information from the report should inform consumers and conversations doctors have with obese or diabetic patients, Dr Gore said.
She recommends a few easy steps for the public to reduce exposure, starting with avoiding water bottles. Refilling a travel cup with water reduces both exposure to the plastic chemicals and the number of bottles that wind up in landfills and oceans.
Also, avoiding microwaving plastics and processed foods can limit chemical exposure.
"When doctors talk about lifestyle to their patients," Dr Gore says, "they typically emphasize healthy diet and exercise, but I would be surprised if, as part of the healthy-diet conversation, they talk about…trying to stay away from microwaving plastics. You may have a healthy meal, but if it's in a plastic container, it's leaching chemicals."
Many Medical Specialties Affected
Dr Gore also advises that not just endocrinologists, but general practitioners, pediatricians, obstetrician-gynecologists, and fertility doctors should emphasize reduction of exposure to these disrupters when they talk to their patients.
She stressed the need for urgent research and testing of chemicals and gave this example of the potential scope of the threat: "In the US, the Toxic Substances Control Act (TSCA) includes about 85,000 chemicals, most of which have not been tested for their health effects, and humans are exposed to many. Not all of these chemicals are EDCs, but if even 1% of them were EDCs, that would be 850 chemicals."
The full statement will be published online in the society's journal Endocrine Reviews in October.
Among the actions, it will call for:
- Further research to more directly establish cause-and-effect relationships between endocrine-disrupter exposure and specific health conditions.
- Regulation to ensure that chemicals are tested for endocrine activity before their use is permitted.
- Industrial partners to create products that test for and eliminate potential EDCs.
- Education for the public and policy makers on ways to keep EDCs out of food, water, and the air, as well as ways to protect unborn children.
Dr Gore also advises rethinking the composition of teams that are researching effects of disrupters to extend beyond endocrinologists.
"We need basic translational research, clinical scientists, healthcare professionals, and physicians who are working with patients and others," she concluded.
The project was funded by the National Institutes of Health, Ministerio de Economía y Competitividad, Generalitat Valenciana, Academy of Finland, Environment and Quality of Life, Sigrid Juselius Foundation, and Turku University Hospital Special Research Fund. Dr Gore is the editor in chief of Endocrinology. Disclosures for the coauthors are listed in the paper.
Endocr Rev. Published online September 28, 2015. Abstract