Controversy still rages over BPA, bisphenol A.
Scientists have found that bisphenol A (BPA), which is used in a variety of consumer products ranging from fizzy-drink cans to food mixers, affects the function of a gene called Kcc2 which is involved in the growth of neurons, or nerve cells, in the brain and spinal cord.
The study, based on rats and human neurons grown in the laboratory, found female nerve cells more susceptible to BPA than male neurons. This might explain why certain neurodevelopmental disorders in humans are more common in females, such as Rett syndrome, a severe form of autism found only in girls, the scientists said.
“Our findings improve our understanding of how environmental exposure to BPA can affect the regulation of the Kcc2 gene. However, we expect future studies to focus on what targets aside from Kcc2 are affected by BPA,” said Professor Liedtke, who led the study published in the Proceedings of the National Academy of Sciences.
Other scientists have, however, criticised the study for exposing neurons to relatively high doses of BPA that would not normally be encountered by the human body. They believe that suggestions of a link between BPA and human disorders are not supported by the evidence when it comes to realistic exposure levels.
Professor Andrew Bartholomaeus of the University of Canberra in Australia, said that any BPA consumed in food or drink is completely metabolised before it enters the blood stream, which means that cells within the body are not exposed to “free” BPA.
Oh, this controversy has been around for while now. Haven’t heard of it? Well here you go, here it is in a concise complete read:
The concern is that BPA can leech from plastic containers into the food or liquid it contains, and when consumed can have negative health effects. The debate is over how to interpret existing evidence about BPA safety, which gives conflicting results. Essentially it is a debate about how to weight different kinds of evidence, and where safety thresholds should be.
What is the conclusion? That there is a small but possibly real effect here. Since toxicity is dependent on dose, we should limit our use of such plastics especially when they can leach out into our foods. Thus, BPA is banned in baby bottles and is being phased out in water bottles and food containers. However, what will replace BPA? Will that be safe? Or worse.