Written by Tonya Mukherjee and Edited by Sorina Long
Since the discovery of BPA’s estrogen-like behavior in the 1930’s, the chemical has become a controversial topic, as consumers and scientists alike are unsure of how prevalent it is and how severe its effects may be [1]. A 2019 study conducted by Washington State University found that up to 90% of Americans have traces of BPA in their system, and human BPA levels have been drastically underestimated, often being as much as 44 times higher than previously assumed [2]. According to the FDA, BPA is relatively harmless and is present in safe and heavily regulated amounts; however, evidence shows that exposure levels are far higher than previously thought, and many studies associate BPA consumption with metabolic health hazards. [3]
BPA, or Bisphenol A, is a structural component found in a variety of food packaging, including beverage bottles and cans [1]. Food packaging materials often migrate into the food within the container, thus introducing BPA into the consumer’s system [4]. Over 300 scientific studies conducted by FDA experts have not associated BPA with any health problems serious enough to prompt BPA safety assessment revisions. However, investigations are still underway, and external studies continue to associate BPA exposure with metabolic, hormonal, and reproductive health problems [4].
Formerly, studies of BPA utilized an indirect method of measurement in which an enzyme solution made from snails was used to convert BPA metabolites, the compounds created as BPA travels throughout the body, into whole BPA. In theory, the conversion process from BPA metabolite to whole BPA conserves how much BPA is actually present. In 2019, assistant professor Roy Gerona of the University of California at San Francisco, developed a new way of measuring BPA through direct analysis of its metabolites, BPA glucuronide and BPA sulfate. They directly analyzed BPA glucuronide and BPA sulfate instead of using the indirect method. Direct BPA glucuronide and BPA sulfate analyses more accurately convey BPA measurements, as byproducts often break down during indirect analysis, thus providing inaccurate BPA exposure data [5]. Surveys of both methods have found that greater BPA exposure results in greater inaccuracy in the indirect test [3]. These findings have scientists speculating that FDA conclusions of BPA safety may be inaccurate. Researchers also speculate that, as the same indirect BPA test has been utilized to test other such hormone disruptors, information on other chemicals may be faulty as well [2, 3].
Despite FDA tests concluding BPA’s safety, external scientific sources consider it one of the most abundant hormone disruptors in the environment. Tests conducted in 2013 found evidence that BPA is detrimental to metabolic health. In fact, multiple studies have found that BPA disrupts androgen and estrogen function, as well as the maintenance of lipid and glucose levels, in various tissues, thus resulting in excessive weight gain or the development of opposite-sex characteristics such as unusual hair growth in women and soft breast development in men [6]. BPA’s involvement in hormonal pathways also has consumers worried about the long-term effects of BPA on male and female fertility and child development [7].
Although human tests primarily involve surveys, observational studies present an extremely strong positive correlation between higher BPA urinary concentrations and the increased prevalence of cardiovascular disease, Type 2 diabetes, liver enzyme abnormalities and obesity [3]. Scientific studies on animal test subjects have associated even low levels of BPA with the damage of cellular signaling pathways, thus affecting rates of hormonal signaling, cell function, sperm and ovary maturation, and many other metabolic and reproductive functions [5].
Conclusively, the discovery of the underestimation of BPA with Gerona’s new technique begs the question of just how harmful the chemical can be to consumers. With 90% of the American population possessing traces of BPA in their bodies, scientists hope to better understand its effects. Although the new method clearly identifies the underestimation of BPA in the American population, and a vast amount of evidence points out the harmful effects of BPA on consumers, the FDA has yet to comment on the results [2].
References:
- “BPA: What, When, Where, How, Why.” Baum Hedlund Aristei Goldman Trial Lawyers, Baum Hedlund Aristei Goldman Trial Lawyers, 2018, https://www.baumhedlundlaw.com/consumer-class-actions/bpa-injuries/what-is-bpa/.
- Bienkowski, Brian. “Federal tests ‘dramatically’ undercount BPA and other chemical exposures.” Environmental Health News, Environmental Health Sciences, 6 Dec. 2019, https://www.ehn.org/how-much-bpa-in-our-bodies-2641524955.html.
- Zaske, Sara. “BPA levels in humans dramatically underestimated, study finds.” Science Daily, Science Daily, 5 Dec. 2019, https://www.sciencedaily.com/releases/2019/12/191205183417.htm.
- “Bisphenol A (BPA): Use in Food Contact Application.” U.S. Food and Drug Administration, U.S. Food and Drug Administration, Nov. 2014, https://www.fda.gov/food/food-additives-petitions/bisphenol-bpa-use-food-contact-application.
- Gerona, R., Sal, S.F., Hunt, A.P. (2019). BPA: have flawed analytical techniques compromised risk assessments? The Lancet Journal, 8:11–13.
- Grasselli, E., Cortese, K., Voci, A., Vergani, L., Fabbri, R., Barmo, C., Gallo, G., Canesi, L. (2018). Direct effects of Bisphenol A on lipid homeostasis in rat hepatoma cells. Chemosphere, 91:1123–1129.
- Migliaccio, M., Chioccarelli, T., Ambrosino, C., Suglia, A., Manfrevola, F., Carnevali, O., Fasano, S., Pierantoni, R., Cobellis, G. Characterization of Follicular Atresia Responsive to BPA in zebrafish by Morphometric Analysis of Follicular Stage Progression. (2018). International Journal of Endocrinology, 2018:1–10