Hormone-Mimicking Chemicals Cause Inter-Species Mating

Science Blog
BPA in rivers leads to breakdown of fish species barriers

Hormone-mimicking chemicals released into rivers have been found to impact the mating choices of fish, a new study has revealed. The controversial chemical BPA, which emits oestrogen-like properties, was found to alter an individual’s appearance and behavior, leading to inter-species breeding. The study, published in Evolutionary Applications, reveals the threat to biodiversity when the boundaries between species are blurred.

The research, led by Dr Jessica Ward from the University of Minnesota, focused on the impact of Bisphenol A (BPA) on Blacktail Shiner (Cyprinella venusta) and Red Shiner (Cyprinella lutrensis) fish which are found in rivers across the United States. BPA is an organic compound used in the manufacture of polycarbonate and other plastics. It is currently banned from baby bottles and childrens’ cups in 11 U.S. states.

“Chemicals from household products and pharmaceuticals frequently end up in rivers and BPA is known to be present in aquatic ecosystems across the United States,” said Ward. “Until now studies have primarily focused on the impact to individual fish, but our study demonstrates the impact of BPA on a population level.”

The team collected individuals of both species from two streams in the state of Georgia. The species were kept separated for 14 days in tanks, some of which contained BPA. On the 15th day behavioral trials were undertaken as individuals from different tanks were introduced to each other.

The scientists monitored any physiological or signalling differences the individuals displayed, such as colour, as well as any behavioral differences during courtship, such as mate choice.

BPA disrupts an individual’s endocrine system, which controls the release of hormones. This impacts behavior and appearance, which in turn can lead an individual to mistake a newly introduced species as a potential mate.

This process poses long-term ecological consequences, especially in areas threatened by the introduction of invasive species. BPA and other hormone-mimicking chemicals can escalate the loss of native biodiversity by breaking down species barriers and promoting the invader.

“Our research shows how the presence of these manmade chemicals leads to a greater likelihood of hybridization between species,” concluded Ward. “This can have severe ecological and evolutionary consequences, including the potential for the decline of our native species.”

Related stories: Interspecies Sex: Evolution’s Hidden Secret?

Corporations Add Equally Toxic ‘BPS’ to BPA-Free Products

Natural Society

We’ve all seen the “BPA-free” labels affixed prominently to new plastic products. And many of us have fallen for the ruse, purchasing these new water bottles and food storage containers thinking we can still enjoy the convenience of plastics without the hormone-altering BPA. But what manufacturers are using in place of BPA might not be any safer. It’s known as ‘BPS‘ and as a matter of fact, it could be even worse.

Bisphenol-A (BPA) has made headlines over the past several years for the growing awareness of its dangers. Namely, it mimics estrogen in the body, throwing hormones out of whack. Although the United States and Europe have banned BPA in baby bottles, Canada remains the only country that has officially declared BPA as a “toxic substance.” Because of this, many people have smartly begun shunning plastics, opting for glass or metal, or choosing the new slick and expensive drinking bottles labeled “BPA-free”.

In place of BPA, manufacturers have begun using something called bisphenol-S (BPS). Unfortunately, there is no indication that BPS is any safer. On the contrary, it could be even worse than the villainized BPA. So, why are manufacturers using it? Well, because they can!

There is little information available on BPS at this point. Scientific research is lacking, and because there is little to say that it’s bad for you, manufacturers don’t have to worry (yet) about the repercussions of putting it in their products and selling it to unknowing consumers.

According to the Environmental Science and Technology, BPS is actually of a “comparable potency” to BPA. Also, it is “less biodegradable, and more heat-stable and photo-resistant” than its predecessor BPA. What does this mean? Well, it has the same estrogen-mimicking qualities and it doesn’t degrade as quickly as BPA, so it can stick around in your body for longer periods of time.

This isn’t a new practice—skirting public fears by playing on their ignorance. Plastic manufacturers know that the information about BPS is still in an infancy stage. They know they can get a few good years off of this “BPA-free” label craze before science catches up with them. So, in the meantime, they will keep selling you their new supposedly-safer products and probably even sell them at a higher price!

The bottom line is that we don’t know everything that is now being included in plastics. They are likely an “alphabet soup of toxic chemicals,” according to Mercola. Even canned goods are lined with BPA. Your best bet is to stick with glass whenever possible for food storage, drinking water, and microwaving (if you still do that).

How Plastic Food Containers Could Be Making You Fat, Infertile and Sick

sott.net, Oct. 27, 2011

In previous articles here, here and here, I wrote about the dangers of an environmental toxin called bisphenol-A (BPA). BPA is a chemical that is found in several plastics and plastic additives. It’s in the water bottles some folks carry to gyms, the canned tomatoes and coconut milk they cook with, and in the baby bottles moms use to feed their infants.

We’ve known for decades that BPA has estrogenic activity. In vivo animal studies and in vitro cell-culture research has linked low-level estrogenic activity associated with BPA exposure to all kinds of fun stuff, like diabetes, ADHD, heart disease, infertility and cancer.

There is now significant evidence suggesting that even low levels of BPA-exposure can cause harm, and this is particularly true in vulnerable populations like pregnant women, infants and the chronically ill. (1)

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