A new analysis of more than 80 studies on Bisphenol A (BPA) has given scientists a global snapshot of humans exposure to this worrisome chemical used in baby bottles, metallic food cans, and other consumer products. And that picture isnt good, according to the authors study.
What we found is that even in developing countries a majority of people sampled have BPA in their bodies, said Laura Vandenberg, Ph.D., with Tufts Universitys Center for Regenerative and Developmental Biology. And were talking about the form associated with harmful effects (in humans).
In her report -- published this week in the online journal Environmental Health Perspectives -- Vandenberg recommended that "precautionary principle be followed until further data on exposure of fetuses and children to BPA become available: the health of the public is at stake."
An organization that represents the chemical industry downplayed Vandenbergs study, saying her opinions are contrary to those of scientific experts who have reviewed the same information.
Multiple studies, however, have linked BPA exposure in humans with cardiovascular disease, diabetes, heart disease, obesity, and reproductive issues. The U.S. Food and Drug Administration (FDA) even went on record earlier this year , saying it has some concerns about the potential effects of BPA on the brain, behavior, and prostate gland in fetuses, infants, and young children.
Those concerns are scientifically documented, Vandenberg said.
Data from multiple sources indicates that the amount of BPA to which humans are exposed may cause adverse health effects, she wrote in her study. This has raised concerns among regulatory agencies all over the world.
During an interview with ConsumerAffairs.com, Vandenberg discussed on her studys findings and the potential effects of BPA exposure in humans.
So often, the idea that is thrown around is that once BPA gets into the body, its innocuous, she told us. But were looking at whats in peoples bodies and that is not true.
BPA is used in a variety of consumer products, including plastic baby bottles, reusable water bottles, metallic food and beverage cans, medical equipment, and dental sealants. Some studies have also detected the chemical in water, sewage, indoor and outdoor air samples, and dust.
Children and developing fetuses are especially vulnerable to potential adverse health effects from BPA exposure, Vandenberg said.
Pregnant women
If I could get our message to a sub-population it would be pregnant women, she said. Im not worried about the moms. Im worried about their fetuses. A lot of attention has been given to baby bottles and removing BPA from them. This might lead people to think that the problem is solved. But fetuses are not exposed to BPA from baby bottles. They are exposed to BPA from their moms.
During their review, Vandenberg and her colleagues analyzed more than 80 studies that measured BPA in humans. Researchers in those studies tested thousands of people around the world -- from various age groups and ethnic backgrounds for BPA in their urine, blood, and other body fluids and tissues.
We were like an oversight committee of all these studies, Vandenberg said. What we wanted to do was take that body of research as whole and ask if it was telling us something that an individual study cant tell us.
Their analysis revealed that many people tested had what Vandenberg called bad or active BPA. The scientific term is unconjugated BPA.
There is free, unconjugated, bad BPA in our bodies and in the bodies of our fetuses and neonates (newborns), she told us.
She elaborated on that point in her report, writing: Available data from biomonitoring studies clearly indicate that the general population is exposed to BPA and are at risk from internal exposures to unconjugated BPA." A biomonitoring study analyzes body fluids and tissues for exposure to various substances. These studies overwhelmingly detect BPA in individuals including adults, adolescents and children.
Vandenberg said her analysis also uncovered flaws with two toxiconkinetic studies used by such regulatory groups as the US Center for Evaluation of Risk to Human Reproduction (CERHR) and the European Food Safety Authority (EFSA) to assess the dangers of BPA in humans.
During a toxiconkinetic study, scientists administer BPA into the body and determine how long it takes to leave, Vandenberg explained. You look at how it gets out of the body -- in the urine or feces.
Ignored studies
Scientists also examine what from the chemical is in when it leaves the body -- the less dangerous form that is metabolized or the bad unconjugated BPA.
The two studies used by the regulatory groups suggest that humans are not internally exposed to BPA, Vandenberg said. But Vandenberg said those findings are unreliable. Those two studies are flawed in so many ways, she said. They are not telling us anything at all.
The studies, for example, relied on estimated levels of exposures to BPA instead of actual measurements of the chemical.
Besides using flawed data, Vandenberg cited another troublesome move by these and other regulatory group. In their previous risk assessments of BPA, they ignored the more than 80 studies that she and her colleagues analyzed.
Were preparing another paper that says those regulatory agencies have only listened to two studies that are highly flawed and ignored these other 80 studies, Vandenberg said. Thats not scientific.
The FDA, she said, ignored the findings of all 82 studies. They do not give scientific reasons for ignoring these studies.
The European Food Safety Authority ignored the 80 studies and only paid attention to the two that are flawed, she said. Thats worse than the FDA. An organization that represents companies in chemical industry said it doesnt give any credence to Vandenbergs study.
There is no new data in this article, and the information has been publicly available for some time, said Steve Hentges, Ph. D., with the American Chemistry Council (ACC). (The) opinions of these authors are quite contrary to the conclusions of recognized experts at scientific regulatory bodies from around the world who have analyzed the same data. The ACC said other studies have shown that BPA exposure does not pose a risk to humans.
Ten regulatory bodies around the world have assessed the science on BPA and have determined that BPA is safe for use in food contact products, the organizations Web site states. Scientific research shows that in humans BPA is quickly metabolized in the intestines and liver and is quickly eliminated from the body. It does not accumulate in blood or tissues. When it is ingested through contact with food, it is rapidly converted into a metabolite (BPA-glucuronide) that has no known biological activity.
Although the FDA has expressed concerns about the safety of BPA in humans, the agency has not banned the chemicals use. But it supports manufacturers plans to stop making baby bottles and infant feeding cup with BPA and to find alternatives for the chemical in the linings of infant formula cans.
The agency, however, is not calling on consumers to stop using these baby products.
FDA is not recommending that families change the use of infant formula or foods, as the benefit of a stable source of good nutrition outweighs the potential risk from BPA exposure, the agency states on its Web site.
Questions to answer
Back in Massachusetts, Vandenberg said additional, long-term studies are needed on BPA exposure in humans and its potential health risks.
There are still scientific questions to answer, she said. We still dont know where all the BPA in our bodies is coming from. We assume most of it comes from cans and plastics, but we dont know for sure. The fact is that BPA is found in all kinds of environmental samples. I just read today that BPA has been found in beach sand and in ocean water.
Asked if the chemical should be banned, Vandenberg said: I mostly approach this from a scientific point of view. There is the strength of science in these 80 studies, which tell a story that every one of us is exposed to BPA. Its in our bodies, in the cells inside our bodies, and that is serious.
There are some who say that science supports a ban of BPA, she added. I firmly believe that we as individuals have a right not be poisoned.
What to do
Vandenberg said consumers can reduce their exposure to BPA by taking the following measures:
• Avoid canned foods or try to cut the number of canned food used by one a day;
• Eat fresh fruits and vegetables whenever possible;
• Reduce or avoid polycarbonate plastic containers. One study cited in Vandenbergs analysis found the urinary concentrations of BPA among a group of college students tested for one week increased 69% when they used polycarbonate bottles. These containers may be a significant source of BPA exposure to individuals in this age group and that interventions would help lower exposure levels, the report states;
• Avoid plastic products with the number 7 stamped on the container.
• Insist that companies disclose how much BPA is in their products. Its unreasonable to expect consumers to protect themselves from BPA if there are no labels to tell people how much BPA is in the product, she said.
Vandenberg and her colleagues received financial support for their analysis from the National Institutes of Health (NIH) and a research fellowship from the National Research Council Brazil.
A copy of the study, Urinary, Circulating and Tissue Biomonitoring Studies Indicate Widespread Exposure to Bisphenol A can be read on the Environmental Health Perspectives Web site.
Analysis of 80 Studies Finds BPA Exposure Widespread...