Unveil the Myths of Bisphenol A —— Interview with Dr. Steven G. Hentges by CCR
COLUMN:ECONOMY AND BUSINESS
Unveil the Myths of Bisphenol A
—— Interview with Dr. Steven G. Hentges by CCR
Dr. Steven G. Hentges is the Executive Director of the Polycarbonate/BPA Global Alliance hosted by the American Chemistry Council (ACC). The PC/BPA Global Alliance consists of the leading manufacturers of BPA and polycarbonate, focusing on the health and environmental aspects of BPA along with a wide range of science-based communication and advocacy activities.
Dr. Hentges has been deeply involved with scientific research on bisphenol A for almost 18 years. He clarified some myths on BPA that often appeared in our daily life especially in the social media.
CCR: would you please introduce BPA and polycarbonate?
Steven: Bisphenol A, abbreviated to BPA, is one of the widely used industrial raw materials. It is basically used for the manufacture of polymers, mainly polycarbonate and epoxy resins. It is solid state substance even at temperature higher than 150° C.
Many of what people say about BPA is misleading. BPA is seldom used by itself, even though it is high volume chemical all over the world. Almost all the BPA is used as intermediate called monomer to produce polymers and actually, the polymers are materials used to produce consumer articles which we contact every day. Very little BPA will get contact with consumers as most of BPA is transformed into plastic or other materials.
Polycarbonate is a macromolecular polymer produced by BPA and other chemical materials. It is one of five major engineering plastics with wide applications in many fields. Polycarbonate is broadly used in automobile, electrical and electronics, building and construction, medical devices due to its clear, lightweight, highly shatter-resistant and other attributes. Particularly, the lightweight attribute of polycarbonate makes it an attractive material to reduce weight and thus to increase the range of the electro or hybrid vehicles. Moreover, polycarbonate is permitted for use in food contact materials around the world.
Polycarbonate is recyclable. The triangle signals with the number 1-7 that we usually see on the plastic containers are the Resin Identification Code (RIC) for the purpose of facilitating recycling and they have nothing to do with the safety. For example, Number 7 is just for other plastics including polycarbonate that are not included by Number 1-6. People can’t and should not rely on that for safety judgement.
CCR: Why has BPA drawn so much attention, from the science community, regulators and the general public?
Steven: There is a long history. The reason why BPA is so popular in the media and with consumers is that, there were some research suggesting BPA could be harmful to us at very low exposure, the same level as we contact on the daily basis. That claim became very popular with scientists who wanted to work on something important. It was attractive to the media because they like scary headlines which can become a popular media topic. NGO was interested in BPA also because BPA is important. So the issue of BPA started from science but went to the media, to NGO and to governments around the world.
Governmental Agencies looked all the scientific evidence and are pretty much unanimous around the world that BPA is safe for us as consumers. The simple example is a short Q & A sheet about BPA on US Food and Drug Administration website—It asks “is BPA safe?” and the answer is remarkable: they say completely in a US way “Yes.”. This answer is based on very extensive scientific research supporting the safety of BPA.
CCR: As food packaging is closely related to human health, what is the current status of polycarbonate use in food packages and containers, especially for baby bottle?
Steven: Polycarbonate is regulated and permitted for use in food contact materials around the world. It is usually used for repeated applications as polycarbonate is durable. In China, according to two National Standards—GB 4806.6 and GB 4806.7, seven kinds of polycarbonate resins as well as other five kinds of BPA-based resins are approved to be used in food contact material and articles. Similar to other authorized materials, there are requirements and limits for its food contact applications. For example, the special migration limit (SML) of BPA for polycarbonate is 0.6 mg/kg, while the actual migration is much lower than the SML.
As for baby bottle, polycarbonate was permitted to be used in baby bottles before but polycarbonate baby bottle can’t be found on the market anymore either in US, EU or China, even though it is safe. Around 2008, BPA was very controversial and drew high attention from the public. So the US manufacturers of baby bottles decided to switch to other materials just because they did not want to deal with the controversy. In EU and China, the regulators decided to settle the issue similar to FDA by prohibiting polycarbonate baby bottles in terms of precautionary reasons rather than safety just because BPA was controversial and there was uncertainty.
In addition, polycarbonate-based food containers can be microwaved, which will not deform due to the heat resistance property of polycarbonate.
CCR: What is your opinion about “BPA-free” labels on consumer products?
Steven: The “BPA-free” label on the product is kind of misleading. If I consider to buy a product, what I want to know is about what the product is made out of and whether it is safe. However, the “free-of” label can only tell us what the product is not made out of and thus misleads consumers to think that products with “free-of” labels are safer than those without such labels. Furthermore, from the regulatory views around the world, BPA is safe to consumers, so it doesn’t make any sense to indicate a product not containing a certain substance that has been proved to be safe.
CCR: What do you think about alternative materials for BPA or polycarbonate?
Steven: It is normal competition in the market place, but we all know that the attributes and safety are really two important things for materials we choose. As for polycarbonate, the combination of its attributes, such as clear, lightweight and highly shatter-resistant, makes it almost unique and thus not easy to be replaced. So it would not make sense to replace polycarbonate if the alternative does not perform that well.