by Introduction to BPA
Bisphenol A, commonly known as BPA, is a chemical used in the production of polycarbonate plastics and epoxy resins. First developed in the 1890s, BPA is now mass-produced around the world with over 6 billion pounds made every year. Its widespread use in consumer products means that human exposure to BPA is almost universal.
Usage of BPA
BPA is commonly found in hard, clear plastic bottles as well as products like sports equipment, medical devices, DVDs, and the lining of canned goods. The chemical is used to make polycarbonate plastics, which are valued for being lightweight, shatter-resistant, and durable. BPA-based epoxy resins are utilized to protect the insides of canned food and beverage containers from corrosion and microbial growth. As a result of its effectiveness and low production costs, BPA remains one of the highest volume chemicals produced worldwide.
Biological Effects of BPA Exposure
Numerous scientific studies have linked BPA exposure to developmental and reproductive health problems. According to research, BPA can disrupt the endocrine system and mimic the effects of estrogen once inside the body. Exposure during pregnancy and childhood has been particularly concerning, as BPA may interfere with normal organ and brain development. Some of the health issues associated with BPA include increased cancer risk, early puberty, infertility, obesity, diabetes, cardiovascular problems, and neurological changes. Animal studies have also found BPA exposure can cause permanent genomic changes that may pass to future generations.
Controversy over Low-Dose Effects
For years, the EPA and FDA relied on studies that claimed low doses of BPA, equivalent to typical human exposure levels, were safe. However, this view has increasingly come under scrutiny. In 2008, the US National Toxicology Program expressed “some concern” about BPA’s health effects and upgraded its classification. More recent research has found BPA capable of harming laboratory animals even at very low doses considered harmless according to past risk assessments. The low-dose effects of BPA challenge toxicology’s traditional views about threshold doses and threaten to raise new regulatory issues. With mounting evidence that BPA levels considered “safe” could still influence biology, the scientific consensus has shifted significantly in recent years.
Government and Industry Response
In 2010, the FDA announced it had “some concern about the potential effects of BPA on the brain, behavior, and prostate gland of fetuses, infants, and young children,” and instituted a review. They have since proposed banning BPA from baby bottles and sippy cups. However, the FDA maintains the chemical is still safe at low levels for adults. Canada took a more precautionary approach and declared BPA toxic in 2010 due to health concerns about fetal exposure and development. Industry groups have disputed links between BPA and health conditions and argue the chemical cannot be definitively proven hazardous at current human exposure levels according to traditional risk assessment methods. Plastics manufacturers oppose changes to regulations that would increase production costs or eliminate viable materials.
Emerging Alternatives and Consumer Demand
Amid the growing controversy, some manufacturers have voluntarily stopped using BPA in infant products due to consumer concern. Alternatives to BPA are available, though they are not universally less toxic or without uncertainty either. In hard plastics, BPA can be replaced by other estrogenic compounds like BPS. For linings of canned goods, alternatives exist but may cost more or impart off-flavors. Silicone, glass, and aluminum are also being adopted by some forward-looking companies. Surveys show that public awareness of BPA’s risks has increased substantially in the past decade and concern over chemical exposures in daily items is growing. Nonetheless, existing supplies of BPA and the lack of cost-effective non-estrogenic replacements continue to hamper the complete transition away from this ubiquitous substance.
Current Status and Outlook
After further review, the FDA continues to assert that BPA is safe at levels currently used in foods, despite calls from scientists for more oversight. Numerous regulatory bodies around the globe now view BPA as a substance of concern and some have instituted policies reducing exposure. Studies continue to refine our understanding of how tiny amounts of hormone-mimicking chemicals can affect biology, redefining what was once considered a safe threshold. Technologies that help monitor chemical levels in our bodies also hint human exposure may be higher than assessed by past risk methods. How to balance public health, scientific uncertainty, costs, and practicality remains an open question. Going forward, regulators, manufacturers, and consumers will be faced with weighing the pros and cons of materials like BPA that have become deeply woven into modern life.
