Bisphenol A or BPA is harmful to humans and is commonly found in bottled water. BPA is a chemical compound used to make plastics and resins since 1950. It is found in polycarbonate (PC) plastics and epoxy resins. Polycarbonate is commonly used as packaging material, such as gallons of drinking water, baby feeding bottles, and tableware, marked with the number 7 on the packaging. Packaging with polycarbonate material is very sturdy and rigid because it can be recycled. Meanwhile, epoxy resins are used to line food and beverage cans and the inner parts of water pipes (EFSA, 2023a; Geens et al., 2012; Lehmler et al., 2018).
Bisphenol A became a hot topic in Indonesia after a health influencer, Dr. Richard Lee, posted on social media about about the risks of consuming bottled water in reusable gallons. He urged housewives to no more using reusable gallons.
Why is Bisphenol A Harmful?
Through multiple toxicity tests in the United States and Europe, Bisphenol A (BPA) is classified as a hazardous chemical. It can affect reproductive function, mammary gland development, fetal brain development, and metabolism. In addition, it is an endocrine disruptor that can interfere with the hormone system. Other health effects such as skin allergies, serious eye damage, autism, heart disease, and respiratory irritation may occur.
The FDA (US Food and Drug Administration) declared BPA dangerous only in 2010 after conducting toxicity testing. They was concerned about the health effects caused by exposure to BPA, such as brain, behavioral, and prostate gland disorders.
Following the United States, the European Union set a TDI (Tolerable Daily Intake) limit for Bisphenol A in 2015. However, in 2023, EFSA conducted a review of the safety of dietary exposure to BPA. As a result, EFSA lowered the TDI from 4 micrograms per kg body weight per day to 0.2 nanograms per kg body weight per day.
How does Bisphenol A Get into the Body?
Tiny amounts of BPA can migrate from packaging into food and beverages. This leads to human exposure through ingestion. The migration occurs when the packaging is washed with hot water or exposed to continuous direct sunlight. In addition, it happens when gallons are distributed from the factory by truck to warehouses and then to stores. Heat from sunlight makes Bisphenol A dissolve into water. According to Rora Daras, Chairperson of the Alliance of Journalists Concerned with Health and the Environment, reusable gallons are washed by spraying hot water at a temperature of around 70ยฐC. Heating at that temperature also allows Bisphenol A to activate.
BPA molecules that decay, enter the human body through two ways, dietary exposure (exposure through consumption of contaminated food and beverages) and non-dietary exposure. The figure below explains the source and route of BPA exposure until it reaches the human body.
How to analyze BPA on Packaging?
Bisphenol A exposure from polycarbonate (PC) containers to food simulants can be analyzed using HPLC-FLD. Research conducted by So-ra Park, Se-Jong Park, etc., used samples of baby bottles, cups, food containers, spoons, food tongs, and vegetable ladles sold in South Korea. They tested the migration of BPA, phenol, p-tert-butylphenol (TBP), and diphenylcarbonate (DPC) to four food simulants (water, 4% acetic acid, 50% ethanol, and n-heptane) at different temperatures.
Validation of research methods related to LOD, LOQ, recovery and precision in detecting migration of BPA, phenol, and TBP using HPLC-FLD and for DPC using HPLC-UV. As a result, the highest levels of BPA (54.3 ยตg L-1) and phenol (43.8 ยตg L-1) migration were found in the 50% ethanol simulant at 70ยฐC (Tables 1 & 2). TBP did not migrate in all food simulants. DPC only migrated from the cup to 4% acetic acid at 70ยฐC and 100ยฐC (Table 3). DPC migration was also found in the 50% ethanol food simulant in cups, ladles, spoons, and food tongs to n-heptane at 25ยฐC.
Table 1. Concentrations (ยตg L-1) of BPA in simulants from polycarbonate samples analyzed by HPLC-FLD.
Table 2. Concentration (ยตg L-1) of phenol in simulants from polycarbonate samples analyzed by HPLC-FLD.
Table 3. Concentration (ยตg L-1) of diphenyl carbonate in simulants from polycarbonate samples analyzed by HPLC-UV.
Thus, food simulant type and temperature are important factors in the migration of BPA and phenol in polycarbonate (PC) samples.
The estimated daily intake (EDI), based on food consumption and food type distribution factors, for BPA, phenol, and DPC was calculated as 0.007, 0.001, and 2.5 x 10-4 ยตg kg-1 body weight/day, respectively. The assessment of intake safety risk through food contact materials was based on the EDI and TDI of each substance. The risk of BPA was calculated by dividing the EDI by the TDI (0.004 ยตg kg-1 body weight/day according to EFSA).
Source:
Sora, Park; Sejong, Park; Mijin Jeong; etc. Fast and simple determination and exposure assessment of bisphenol A, phenol, p-tert-butylphenol, and diphenyl carbonate transferred from polycarbonate food-contact materials to food simulants. 2018. Chemosphere: Republic of Korea. https://doi.org/10.1016/j.chemosphere.2018.03.185
https://www.webmd.com/children/bpa
https://www.eea.europa.eu/publications/peoples-exposure-to-bisphenol-a/
