Bisphenol A Lucas Stoiber CBE 555 Oct. 7 th 2008

What is Bisphenol A? BPA First synthesized in 1891 Condensation of acetone with phenol In 1930s it was found to be an artificial estrogen (similar to DES)

BPA in plastics In the 1940s and 1950s it was discovered that BPA can be used in the synthesis of polycarbonate and epoxy resins (#7) Currently over 2 million tons are produced world wide In the U.S. it is made by Bayer, Dow, GE, Hexion, and Sunoco Also used as a polymerization inhibitor in PVC (#3)

Epoxy resin Epoxy is produced from a reaction between epichlorohydrin and bisphenol-a

Where do we find BPA?

Common uses Dental sealants CDs Eye glasses Food and beverage can coatings Reusable water and baby bottles Film Water pipes and sealants in water towers Etc.

Possible health concerns BPA is an endocrine disruptor An endocrine disruptor is a chemical that mimics hormones Potentially causes problems with the reproductive system Our Stolen Future

Animal Studies Animal studies have shown that low doses of BPA can cause breast cancer, testicular cancer, diabetes, hyperactivity, obesity, low sperm counts, miscarriage and a host of other reproductive failures. Shown at concentrations as low as 2 μg/kg/day in mice Hundreds of studies show that BPA is harmful in animals

Human Issues BPA leaches from the plastics 93% of Americans tested had BPA in their urine Highest intake levels in infants Average levels between 0 and 14 μg/kg/day

Government Reactions Certain phthalates have been banned from toys and other objects used by infants and toddlers in the EU, Japan, Mexico, and California Mainly in PVCs BPA is not one of these

Canada In April 2008 Health Canada classified BPA as toxic to human health and the environment Announced intent to ban the import, sale, and advertisement of polycarbonate baby bottles containing bisphenol A

Companies respond Wal-Mart imediately stopped sales in all its Canadian stores of food containers, water and baby bottles, sippy cups, and pacifiers containing BPA. Promised to do the same in the U.S. by 2009 CVS, Toys-R-Us, Nalgene, Playtex and others promise to remove BPA

U.S. Legislation Charles Schumer (D-NY) introduced a bill to the Senate to ban BPA in children’s products (Bill # S.2928) Edward Markey (D-MA) introduced a bill in the house to ban BPA in food and beverage containers (Bill # H.R.6228 )

FDA The FDA evaluation only uses tests where the BPA is ingested Assumes that BPA is much more easily metabolized by primates than mice Determined the No Observable Adverse Effect Level to be 5 mg/kg/day The tests used tend to favor tests performed by industry

Other agencies The European Food Safety Authority established the Tolerable Daily Intake to be 50 μg/kg/day Japan has said there is no risk Canada now states that BPA does not pose a risk

National Toxicology Program findings

Lang Study First human study Higher concentrations of BPA in urine were associated with higher prevalence of heart disease, diabetes, and liver-enzyme abnormalities.

Lang, I. A. et al. JAMA 2008;300: Estimated Mean Bisphenol A (BPA) Concentrations in Relation to Reported Diseases and Conditions

Alternatives Copolyesters no alternative that works as well to prevent spoilage and extend shelf life for canned foods as the BPA epoxy resins used in can linings

Conclusions More testing needs to be done Impossible to avoid at this point Breast feed infants if possible, otherwise use glass or BPA-free bottles

References b1_01_02_FDA%20BPA%20Draft%20Assessment.pdf b1_01_02_FDA%20BPA%20Draft%20Assessment.pdf assn.org/cgi/content/full/300/11/1303?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fullte xt=bisphenol+a&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT assn.org/cgi/content/full/300/11/1303?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fullte xt=bisphenol+a&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT assn.org.ezproxy.library.wisc.edu/cgi/content/full/298/13/1499?maxtoshow=&HITS=10&hits=10&R ESULTFORMAT=&fulltext=bisphenol+a&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT assn.org.ezproxy.library.wisc.edu/cgi/content/full/298/13/1499?maxtoshow=&HITS=10&hits=10&R ESULTFORMAT=&fulltext=bisphenol+a&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT assn.org.ezproxy.library.wisc.edu/cgi/content/full/300/11/1353?maxtoshow=&HITS=10&hits=10&R ESULTFORMAT=&fulltext=bisphenol+a&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT assn.org.ezproxy.library.wisc.edu/cgi/content/full/300/11/1353?maxtoshow=&HITS=10&hits=10&R ESULTFORMAT=&fulltext=bisphenol+a&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT

Other stuff American Chemical Council states an average adult consumer would have to ingest more than 230 kilograms (or about 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 American Dental Association believes any concern about potential BPA exposure from dental sealants or composites is unwarranted at this time. When compared with other sources of BPA, these dental materials pose significantly lower exposure concerns. Environment Canada states that BPA in the environment can harm fish and other organisms Some professors suggest that PVCs will go the way of asbestos and lead

Dose (µg/kg/day) Effects (measured in studies of mice or rats, descriptions are from Environmental Working Group) [42][34]Environmental Working Group [42][34] Study Yea r 0.025Permanent changes to genital tract2005 [43] [43] Changes in breast tissue that predispose cells to hormones and carcinogens 2005 [44] [44] 2increased prostate weight 30%1997 [45] [45] 2 lower bodyweight, increase of anogenital distance in both genders, signs of early puberty and longer estrus [46] [46] 2.4Decline in testicular testosterone2004 [47] [47] 2.5Breast cells predisposed to cancer2007 [48] [48] 10Prostate cells more sensitive to hormones and cancer2006 [49] [49] 10Decreased maternal behaviors2002 [50] [50] 30 Reversed the normal sex differences in brain structure and behavior 2003 [51] [51] 50 U.S. human exposure limit (not a result from an animal study, but a guideline set by EPA) 1998 [52] [52]