Bisphenol A in plastic and its association with metabolic syndrome

New research by the University of Cincinnati (UC) shows that the chemical used to make hard plastics - bisphenol A (BPA) - is a risk factor for metabolic syndrome and its consequences.

In an experimental study using human adipose tissue, UC's team found that BPA inhibits an essential hormone, adiponectin, responsible for regulating insulin sensitivity in the body and posing a risk of Higher metabolic syndrome for humans.

Metabolic syndrome is a combination of risk factors including decreased ability to react with insulin, high blood sugar and lipid levels. According to the American Heart Association, about 25% of Americans suffer from metabolic syndrome. If left untreated, it can lead to serious health problems such as coronary artery disease, heart failure and type 2 diabetes.

Dr. Nira Ben-Jonathan and colleagues have for the first time published scientific evidence on the health impact of BPA with appropriate doses in the environment equivalent to the average exposure level in humans. Previous studies have focused on animals with high BPA doses.

Their findings were published in the journal Environmental Health Perspectives, online August 14, 2008. This scientific data is added just before the Federal Drug Administration meeting on the safety of chemicals in consumer products September 16, 2008.

Ben-Jonathan, professor of cancer and cell biology at UC, studied BPA for more than 10 years, saying: 'Many people really care about the health impact of BPA. Because the scientific evidence against this chemical is increasing, there needs to be adequate attention to reduce the future harms'.

These polycarbonates contain bisphenol A. (Photos; University of Cincinnati).

She added: 'Human tissue testing is the most effective way to test the effect of BPA. It is an interesting breakthrough because epidemiological studies of the effects of BPA on humans are difficult because most people have been exposed to it. ' Scientists estimate that more than 80% of people tested have moderate levels of BPA in their blood. UC's research is designed to simulate the actual human exposure level (from 0.1 to 10 nanomolar), thereby enabling a direct correlation between human exposure and health impacts. .

To carry out the study, scientists at UC collected fresh fat tissue from Cincinnati patients doing some types of breast or abdominal surgery. These samples include 3 types: breast tissue, subcutaneous tissue, and visceral tissue (around the internal organs).

The tissue is immediately taken to the laboratory and exposed to different levels of BPA or estrogen for 6 hours to observe the effect of different amounts of BPA on adiponectin levels. The effect of BPA is then compared with the effect of estradiol, the natural form of estrogen in humans.

They found that exposing tissues to BPA levels within the normal range of human exposure would inhibit hormones that protect people from the metabolic syndrome. Ben-Jonathan said: 'The results are especially significant because we do not perform on a patient or a tissue type. We use different adipose tissue from many patients and all have a negative reaction to BPA '.

Participants include marshal Eric Hugo, Dr. Terry Brandebourg, Dr. Jessica Woo, Dr. J. Wesley Alexander and surgeon Jean Loftus of Christ Hospital. The National Institute of Environmental Health Sciences has funded research.