The Horrors of Bisphenol-A Lining Plastic Containers

BPA chemicals originating from plastics are harming our environment, leading to problems in the reproduction of wildlife ranging from mice to reptiles, according to recent studies.

Many plastics have a thin coat of what is called Bisphenol-A (BPA). This chemical is commonly found in containers such as water bottles and canned foods, preventing the container from contaminating the food or water. However, the use of this chemical creates more problems.

BPA negatively affects animal reproduction and increases rates of estrogen levels. Estrogen is commonly known as a sex determinant hormone that is responsible for regulating the female reproductive system as well as the secondary characteristics that follow such as wide hips and developed breasts.

Satomi Khono, a professor at the Loyola University of Chicago that specializes in animal toxicology, found that additional estrogen during the developmental stage will harm reproduction when they are mature.

“The most we worry about is the developmental exposure to estrogen between humans and animals,” Khono states.

Khono is familiar with two different examples and results of BPA testing among animals.

In one study, scientists exposed young female mice to BPA and observed what would happen to their estrogen count. Research results concluded that estrogen began to mature at a quicker rate, speeding up their menstrual cycle. Meaning, when these mice are fully grown, they will have a harder time reproducing.

“When the baby becomes mature, then the menstrual cycle or estrocycle will be different because the responsiveness to the estrogen will be different,” Khono states.

In another study, scientists began to test the temperature dependent sex determination by exposing BPA to caiman reptile eggs. The temperature of a reptile egg determines their sex because they do not have sex chromosomes. However, studies showed the exposure of the BPA chemical made this system sensitive, turning what could be male reptiles into females.

Lead scientist Cora Stoker found that Bisphenol-A can hinder the sex of the egg because this chemical can mimic estrogen cells. By creating more of these cells, even at male reproducing temperatures, it alters the sex of the reptile.

This will create a higher female to male population and potentially wipe out male caiman reptiles entirely.

Originally, discovering the dangers of BPA had been completely accidental. In the book Our Stolen Future, written by Peterson Myers, CEO and Chief Scientist at a non-profit organization called Environmental Health Sciences, he mentions a study conducted at Stanford University School of Medicine in the early 1990s that found BPA became a source of contamination in their experiments.

Researchers began testing with estrogen-sensitive cells because they discovered a protein in yeast that was binding to estrogen. This discovery would mean that there’s a primitive estrogen receptor and leads to a hormone normally attached to this receptor. However, after attempting to find this “hormone”, the discovery later concluded to be a contaminant; BPA.

Myers states that the source of contamination came from the polycarbonate flasks in their lab that sterilized the water used in their experiments.

Because of this unplanned discovery, researchers are now able to study how BPA specifically harms estrogen cells. Now that this has been uncovered, researchers can now look into the mysterious case of the sexually confused fish near the Atlantic.

John Sumpter, a biologist with Brunei University in Uxbridge studying the role of hormones in fish reproduction, was asked to help solve this mystery happening in lagoons close to sewage treatment plants.

Many English fishermen reported strange activity amongst rainbow trout in River Lea, 50 miles north of London.

“The problem was not the usual fish kills that can occur because of pesticides or low oxygen levels,” Peterson Myers states in his book. “Nor did the fish appear to have any obvious disease. But many looked quite bizarre. Even experienced fishermen could not tell if a fish was male or female, for they showed male and female sexual characteristics at the same time.”

This strange phenomenon leads to the assumption that the fish experiencing these symptoms are going through what scientists call intersex. Myers explains this as an individual (animal) that becomes “stranded” between two sexes.

Government fisheries have suspected the culprit of this activity to be leaked hormones in the water. To test this, Sumpter had to examine the levels of egg-yolk protein, called vitellogenin, in the presumably male fish.

“Although males do not produce eggs, their livers will nevertheless produce vitellogenin if they are exposed to elevated levels of estrogen,” Sumpter states. “Since this response is extremely dependent on estrogen, vitellogenin levels found in male fish provide a good indication of estrogen exposure.”

After a week of testing, Sumpter and his team found that the levels of vitellogenin in the rainbow trout’s blood were 500 times higher than normal and continuously climbing. Following Sumpter’s curiosity, he sent out a nationwide survey only to find that 15 other testing cites also had skyrocketing results. The spread of intersex fish has now become a national problem.

BPA is a nightmare for estrogen cells. Scientists are not only concerned with the dangers this impact brings to animal reproduction, but also question how this will affect humans as well.

“If something is happening in the animals, it is coming to the humans because we share the same environment and share the same water,” Khono states.

Since BPA lines containers, this chemical is not soluble and creates risks to our drinking water. This chemical will not break down once it is in contact with foods or liquids, giving the chance for BPA to enter our ecosystem.

The federal government began regulating plastics containing BPA and manufacturers are beginning to make BPA-free alternatives. The U.S. Food & Drug Administration (FDA) released a statement in 2012 saying manufacturers have begun to remove BPA from items such as baby bottles, sippy cups, and infant formula.

However, the FDA released a statement following this removal.

“An amendment of the food additive regulations based on abandonment is not based on safety but is based on the fact that the regulatory authorization is no longer necessary for the specific use of the food additive because that use has been permanently and completely abandoned,” the FDA states.

Meaning, health was not the main reason why this dangerous chemical was removed from the manufacturing of these items. It was removed because these manufacturers found another way to make the same product.

Even though these are small steps towards BPA-free materials, this chemical is still commonly used in most canned foods and water bottles.

Not only are we exposed to BPA in food or water containers, but there is also a chance of consuming contaminated fish as well. Plastics that enter our lakes become a food source for fish, affecting their health as well as potentially harming ours.

“Over time the polymer chains of BPA break down and can enter the human body in many ways from drinking contaminated water to eating a fish that is exposed to the broken-down toxins,” Gianna Andrews, author of “Plastics in the Ocean Affecting Human Health”, states.

If BPA enters our bodies, there is an opportunity for humans to experience what other animals have already struggled with.

The exposure of BPA has proven multiple cases of harming reproduction in animals and it is only a matter of time before humans are harmed as well.