(Ivanhoe Newswire) -- Three recent studies suggest polychlorinated
biphenyls, or PCBs, may alter the development of brain cells. They linked
exposure of PCBs, chemicals found in the environment and sometimes in fish, to
neurodevelopmental problems in children.
PCBs were banned in the 1970s due to their high toxicity and inability to break
down in the environment. Prior to the ban, PCBs were used in electronics,
pesticides and flame retardants. Today, traces of the chemical dumped into the
environment in years past are still leaking into the air and bodies of water,
contaminating fish that people eat.
Researchers did not understand the exact link between PCBs and the effects on
children before these three studies.
Environmental Health Sciences published a study that demonstrates PCBs are
altering dendritic growth and plasticity. The significance is in that these
characteristics are linked to autism, schizophrenia and mental retardation.
The second study, featured in Toxicology and Applied Pharmacology, measured the
excitability of neurons in the hippocampus by exposing rats to two differently
structured PCBs. The results showed an understanding of how PCBs may impact
human neurodevelopment.
Appearing in PLoS-Biology, a third study explained the effects learned from the
first two.
“Our results show that PCB binds directly to ryanodine receptors and locks the
channel in the open state, causing mayhem in calcium signaling," Isaac N. Pessah,
director of the UC Davis Center for Children's Environmental Health in Davis,
Calif., and co-author of all three studies, was quoted as saying.
Now that the PCB toxins have been linked to the causes of specific neurological
disorders, researchers hope to be able to identify and develop potential
treatments.
SOURCE: Environmental Health Sciences, Toxicology and Applied Pharmacology, PLoS-Biology,
published online
