Bisphenol A, or BPA, is a chemical present in many hard plastics that people use every day. Experts have linked higher BPA doses with infertility and other health problems.

According to the National Institute of Environmental Health Sciences (NIEHS), BPA is present in some water bottles, baby bottles, dental fillings and sealants, dental and medical devices, safety equipment, compact disks, household electronic items, and sports equipment. It also occurs in epoxy resins, which coat the inside of food and drink cans.

There are concerns that it may disrupt hormones. Moreover, studies in animals have suggested it may be toxic.

BPA is a commonly used chemical. People experience frequent exposure to very small amounts of BPA through food, drinks, and water supplies, because small amounts may migrate from food packaging. However, as the amounts are small, the Food and Drug Administration (FDA) considers BPA safe.

In this article, we discuss what BPA is, what its sources are, and what impact it might have on human health.

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BPA is an endocrine disruptor. The Environmental Protection Agency (EPA) notes that BPA can imitate the body’s hormones and interfere with the production of, response to, or action of natural hormones. For example, it can behave in a similar way to estrogen and other hormones in the human body.

According to the NIEHS, there is limited research to show how endocrine disruptors affect humans, but some research has found they can harm animals. However, even a small amount may have developmental and biological impacts, because the balance of hormones is so sensitive.

Research suggests BPA can impact human health in various ways. Below are some of them.

Reproductive disorders

In 2013, scientists published study findings showing that BPA exposure can affect egg maturation in humans.

A 2015 review found evidence that BPA can interfere with endocrine function involving the hypothalamus and pituitary gland.

The researchers suggest that this type of action can affect puberty and ovulation and may lead to infertility. They add that the impact may be “lifelong and transgenerational.”

According to a 2009 study that looked at the effect of males’ exposure to BPA at work, BPA may affect male fertility. The findings indicate that high level exposure may increase the risk of erectile dysfunction and problems with sexual desire and ejaculation.

Heart disease

Research in humans has linked even low dose BPA exposure to cardiovascular problems, including coronary artery heart disease, angina, heart attack, hypertension, and peripheral artery disease.

Findings from animal studies indicate this type of exposure could trigger arrhythmias, atherosclerosis, and blood pressure changes.

Type 2 diabetes and body weight

There is evidence that human exposure to BPA may contribute to:

Tests in animals have shown that BPA may aggravate or raise the risk of:

Fetal brain development

Environmental exposure to BPA has the potential to affect the developing brain during gestation, according to research.

The impact includes changes in structural development, interference with estrogen regulation, and DNA modifications. This could have effects on social behavior and anxiety after birth, says one 2011 study.

Breast and prostate cancer

Scientists believe BPA, with its estrogen-like behavior, could increase the risk of breast, prostate, and other cancers in people who experienced exposure to the chemical in the womb.

In 2015, a group of researchers concluded that exposure to BPA before birth could have long-term effects on carcinogenesis in certain organs. This in turn could lead to the development of hormone-related cancers.

In 2009, scientists reported that BPA could interfere with the effectiveness of chemotherapy in breast cancer treatment.

Asthma

Research suggests there may be a link between exposure to BPA before or after birth and a higher risk of wheezing or asthma.

Public authorities set BPA safety levels, but concerns remain about degrees of exposure.

One study by the Centers for Disease Control and Prevention (CDC) found BPA in nearly all human urine samples, suggesting that exposure is widespread across the United States.

The CDC note that people commonly experience exposure to low levels of BPA when they consume food or water stored in containers made with the chemical.

Children may also experience exposure by touching items made with BPA and then putting their hands in their mouths or by putting their mouths on the item.

Other means of exposure include having dental sealants that contain BPA and working in places that manufacture products with BPA in them.

Thermal paper and carbonless paper may also contain varying levels of BPA, which gets onto the hands and fingers. Thermal paper is commonly used in boarding passes, luggage tags, and receipts.

BPA may enter the system through the skin or when a person places their fingers in their mouth.

A 2009 study of 77 Harvard College students found 1 week of drinking water from polycarbonate bottles increased the levels of BPA by two-thirds. This suggests that regular water consumption from such bottles significantly increases a person’s exposure to BPA.

BPA features in some baby feeding bottles, so breastfeeding an infant is likely to reduce levels of BPA exposure.

How serious is the risk?

A 2010 report by the National Toxicology Program concluded that levels of BPA raise:

  • some concern about the effect on the brain, behavior, and prostate gland in fetuses, infants, and children
  • minimal concern about the effect on the mammary gland and early puberty
  • negligible concern that BPA exposure will lead to fetal abnormalities, low birth weight, and reproductive problems

In 2017, the CDC noted that there was evidence BPA affects reproduction in laboratory animals, but added that more research is necessary.

A 2018 review by the FDA did not find any new evidence suggesting it should review its safety advice on BPA.

While experts recognize that BPA may be hazardous, a report about the dangers of BPA for the World Health Organization (WHO) points out that, in investigations, exposure tends to be higher than what it usually is in most environments.

The EPA is continuing to monitor the findings but is not currently planning to recommend new guidance.

The FDA supports the use of BPA in current food packaging, because the amount that leaches into food is small.

It is difficult to avoid BPA, because it is so prevalent. However, a person can try to minimize their exposure by doing the following:

  • avoiding microwaving polycarbonate food containers
  • bearing in mind that containers with recycle codes 3 or 7 may have BPA in them
  • reducing the consumption of canned foods
  • choosing glass, steel, or porcelain containers for hot food, rather than plastic
  • looking for BPA-free baby bottles

In 2011, some scientists measured the levels of BPA in people’s bodies after just 3 days of their eating a fresh food diet, with no products taken from a can or plastic packaging. They found that levels of BPA fell significantly during this time.

BPA is a chemical that is present in hard plastics, including drinking water bottles and many household items.

Research has shown that exposure to BPA can disrupt the functioning of the endocrine system. However, the levels of exposure in most people’s daily lives are unlikely to result in serious harm.

More research is necessary to understand the effects that exposure to BPA has on human health.