BPA: Government Initiative Fails to Protect the Most Vulnerable
On October 17, 2008, the Canadian government began drafting the first regulations on the import and sale of baby bottles and infant formula cans that contain bisphenol A (BPA).1
Environment Canada scientists determined that these were the primary methods of exposure for infants, the age group currently though to be most at risk. They maintain that these current levels of exposure are safe for newborns, and that this regulation is solely a precautionary measure.1
BPA is a plastic by-product commonly found in milk cartons, water bottles and cans that can leach from the container into the food.2 A survey by the Center for Disease Control found that 93% of the population had detectable levels of BPA in their urine, as well as in their blood.3,4 It has also been detected in the milk of nursing mothers 5, in the amniotic fluid of pregnant women and in the blood plasma of the fetus and afterbirth.2,5,6 BPA is a concern for Health Canada because it has been shown to disrupt the endocrine system of the body.7
The endocrine system is an important regulatory network consisting of hormone-secreting glands throughout the body. Together, these glands and hormones play a crucial role in the short and long-term regulation of the growth and reproductive functions of the body.8 The endocrine system is also important for the development and metabolism of the cardiovascular, musculoskeletal, immune and central nervous systems.8
“Endocrine disruptors” (EDs) is an all encompassing term for chemicals that have the ability to interfere with the endocrine system.9 Some chemicals may indirectly interfere with the endocrine system due to their molecular similarity to natural body hormones.8,9 This gives the chemical the ability to bind and activate the same cell receptors sites, thereby mimicking the natural action of the hormone.8,9 Other chemicals may do the opposite, and instead bind and block cell receptor sites, preventing the natural action of the hormone in the body.8,9 Finally, some chemicals have the ability to directly interfere with the production, release, transport, metabolism and elimination of hormones.8,9 Commonly used pharmaceutical, agricultural and commercial products, such as birth control pills, pesticides, and BPA, all have endocrine disrupting properties.10
The United States National Toxicology Program found credible evidence that BPA has an impact on the endocrine system, even in small quantities.11 BPA is a particularly potent ED because of its ability to bind to all types of estrogen receptors in the body.7,12,13,14 Studies have shown that EDs increase the risk of cervical cancer, breast cancer and are a possible cause of miscarriages.15,16,17
Recently, scientific investigations have turned to global trends in reproductive health. Studies have revealed an overall declining average in testosterone levels, sperm count and quality and a simultaneous increase in genital abnormalities and testicular cancer.18,19,20,21 As the data accumulates over the years, so do the questions: Could the increase of endocrine disruptors in the environment be related to these trends in human fertility?
In both animals and humans, fetal exposure to BPA can cause permanent developmental malformations 2. BPA circulating in the body of the female can be transmitted to the fetus, where it can accumulate to levels that create cellular damage.22 In males, prenatal exposure to BPA can cause a decreased daily sperm production, increased prostate size and malformed urethras.23,24 In females, prenatal exposure to BPA can cause abnormalities in the mammary gland, the ovaries and the uterus.2,17,25
Health Canada’s screening assessment of bisphenol A included Canadians of all ages, but focused on newborns and infants of up to 18 months.26 They concluded that infants were the most vulnerable age group and that baby bottles and infant formula cans were the primary methods of exposure.26 Unfortunately, their assessment seems to ignore the most vulnerable stage of life and method of exposure: exposure through the mother during pregnancy, because it is during this stage where BPA can cause life long birth defects.
Over the next three years, the government plans to dedicate $1.7 million to BPA research 1, which begs the question: How much more research do we need in order to discover what we already know? The health of the mother is intrinsically linked with that of the fetus. The health of the fetus will determine the health of the child, and could possibly determine the fertility of the future generation of Canadians. The ban on baby bottles and infant formula cans is a step in the right direction, but it will not protect children from the BPA damage that occurred while in the womb. The government needs to enforce regulation to phase out all products containing BPA and demand the use of safer alternatives instead, because government policy aimed at protecting newborns from BPA exposure will inevitably fail – unless it also protects the mother.
Written and Researched by Aisha Parkhill-Goyette
1 Health Canada. 2008. Government of Canada Protects Families With Bisphenol A Regulations. Retrieved Feb 23, 2009 from http://www.hc-sc.gc.ca/ahc-asc/media/nr-cp/_2008/2008_167-eng.php
2 Maffini, M., Rubin, Beverly, Sonnenschein, Soto, A. 2006. Endocrine disruptors and reproductive health: The case of bisphenol-A. Molecular and Cellular Endocrinology 254-255: 179-186.
3 National Institute of Environmental Health Science. 2009. Since You Asked –Bisphenol A. Retrieved April 4rth, 2009 from http://www.niehs.nih.gov/news/media/questions/sya-bpa.cfm#20
4 Takeuchi, T., Tsutsumi, O. 2002. Serum bisphenol A concentrations showed gender differences, possibly linked to androgen levels. Biochem. Biophys. Res. Commun. 291: 76–78.
5 Sun, Y., Irie, M., Kishikawa, N., Wada, M., Kuroda, N., Nakashima, K. 2004. Determination of bisphenol A in human breast milk by HPLC with column-switching and ﬂuorescence detection. Biomed. Chromatogr. 18: 501–507.
6 Ikezuki, Y., Tsutsumi, O., Takai, Y., Kamei, Y., Taketani, Y. 2002. Determination of bisphenol A concentrations in human biological ﬂuids reveals signiﬁcant early prenatal exposure. Hum. Reprod. 17: 2839–2841.
7 Markey, C.M., Michaelson, C.L., Sonnenschein, C., Soto, A.M. 2001. Alkylphenols and bisphenol A as environmental estrogens. In: Metzler, M. (Ed.), The Handbook of Environmental Chemistry. Part L, Endocrine Disruptors—Part I, vol. 3. Springer-Verlag, Berlin Heidelberg, pp. 129–153.
8 Kidd, K., Blanchfield, P., Mills, K., Palace, V., Evans, R., Lazorchak, J. & Flick, R. 2007. Collapse of a fish population after exposure to a synthetic estrogen. Proceedings of the National Academy of Sciences 104(21): 8897-8901.
9 Ropero, A.B., Alonso-Magdalena, P., Ripoll, C., Fuentes, E., Nadal, A. 2006. Rapid endocrine disruption: Environmental estrogen actions triggered outside the nucleus