An industrial chemical, Bisphenol A (BPA) is the building block for polycarbonate plastic resins, epoxy resins, and other products. It is used for making lightweight, high-performance plastics that are tough, optically clear, have high resistance to heat and electricity.
Why should I be aware of this?
In the recent times, the debate about Bisphenol A (BPA), one of the most commonly used chemicals in the world, is no longer restricted to biotech experts and regulators, but has entered the living rooms of concerned families.
Even as manufacturers maintain that their products are safe and back it with earlier research, recent research has shown that BPA, even in very small amounts, may affect fetuses and children. These reports have forced people to think and they want to know more. It has highlighted the safety, or non-safety, of foods and beverages packaged in polycarbonate containers made from BPA. BPA is also found in baby bottles and water bottles and food and beverage containers.
How does this affect me?
Health concerns regarding BPA are not new. Researchers have been testing the chemical for side effects for some time now. Of most concern in the NTP report is the possible connection between BPA exposure and developmental or reproductive disorders. Animal testing also indicates a possible link to breast cancer and prostate cancers.
All about BPA
BPA is used in digital media (e.g., CDs, DVDs), electrical and electronic equipments, automobiles, sports safety equipment, reusable food and drink containers and many other products.
Epoxy resins, another end-product of BPA, is used in engineering applications such as electrical laminates for printed circuit boards, composites, paints and adhesives, as well as in a variety of protective coatings. Some other forms of epoxy resins are widely used as protective liners in metal cans to maintain the quality of canned foods and beverages. BPA is also used in dental sealants which are used in preventing tooth decay and in maintaining dental health.
Based on the data reported in the three studies involving application of sealant to teeth, it appears that low levels of BPA may be released from certain sealants, although only during a short time period immediately after application of the sealant. Further, no detectable levels of BPA have been found in blood after application of a sealant that releases low levels of BPA into saliva
In 1996, tests done on patients treated with dental sealants at the University of Granada in Spain, showed traces of BPA in their saliva.
BPA proponents' points of view
Proponents of BPA say the health concerns arise from studying the effects of BPA exposure in animals, not people. They also say much of the research is based on injections of BPA and not oral ingestion, the way people gain exposure. There is the possibility that the different avenues of administering the chemical require different processes for metabolization and may skew the safety outcome
BPA safety data
In a paper published in Current Biology, Dr. Patricia Hunt and her co-authors reported finding a chromosomal abnormality in mouse eggs after exposure to BPA. The research did not look for any potential effects on reproduction or development, and Dr. Hunt herself has acknowledged that no connection between her results and human health has been established.
Government agencies in the U.S., Europe and elsewhere have reviewed the research data and confirm that polycarbonate plastic and epoxy resins may be safely used in contact with food (Ref. 14, 56). The research demonstrating the safety of BPA includes internationally accepted tests designed to examine potential reproductive and developmental effects, upon which governments rely to assess safety. These tests, examining laboratory animals over multiple generations and conducted according to internationally recognized standards, coupled with the assessment of those tests by government agencies in the U.S., Europe, and Japan, clearly support the safety of polycarbonate plastics and epoxy resins.
Typical levels of human exposure to BPA are about 1 million times below levels that have been demonstrated not to cause adverse effects in the internationally recognized multi-generation reproductive toxicity studies. Numerous recent studies that directly measure human exposure to BPA have demonstrated that exposure to adults and children are many times lower than the levels tested.
BPA does not accumulate in the body. The very small amounts of BPA that may be taken into the body are rapidly excreted. The result is that reproductive organs would have no significant exposure to BPA and, thus, essentially no opportunity for BPA to cause the effects reported in the Current Biology study.
What can I do?
Even as the BPA controversy rages on, without any firm conclusions being reached, the US National Institute of Environmental Health Services has made a few suggestions to minimize any risk that might be proven conclusively at a later date.
- Don’t microwave polycarbonate containers. These containers are strong, often clear like glass, but practically shatter-proof. High temperatures cause the polycarbonate to deteriorate, releasing BPA into the food being microwaved.
- Look for the number 7 in the recycle code. The number 7 indicates the presence of BPA.
- Avoid canned foods whenever possible. Canned goods are lined with an epoxy resin made from BPA that is used to increase shelf life and limit the metallic flavor that once leached into many canned goods.
- Use glass, porcelain, or stainless steel food containers whenever possible. *This is especially important if the food or beverage is hot.
- Use only BPA-free baby bottles.
- In 2002, approximately 2.8 million tons of bisphenol A (BPA) was produced globally.
- First synthesized in 1905, bisphenol A became a critical building block for the 20th century.
- Numerous validated studies demonstrate that current bisphenol A manufacturing and use patterns pose virtually no risk to the environment.
- A consumer would have to ingest more than 500 pounds of canned food and beverages every day for an entire lifetime to exceed the safe level of BPA set by the U.S. Environmental Protection Agency.
- Studies have reported that trace levels of bisphenol A (BPA) may be released from certain dental sealants, but only during a short time period immediately after application of the sealant.
- About BPA
- The BPA Controversy: What’s A Person To Do?
- BISPHENOL-A CONSUMER HEALTH & SAFETY INFORMATION
- Resin Dental Sealants and Bisphenol A Oral Exposure
- Debate rages over safety of plastic chemical BPA in everyday items