Autism May be Caused by Everyday Chemicals

By Ina Woolcott

Unborn babies in the womb and breastfed children exposed to an everyday variety of chemicals may be at a greater risk of development disorders such as autism, scientists claim. They have discovered that a group of PCB (polychlorinated biphenyl) compounds, previously regarded as harmless, may in fact damage the sound processing part of the brain. Children who have developmental disorders, such as autism and language impairments, have an auditory cortex responding abnormally to sound. There are some scientists who reckon this is the basis of the disorders.

PCBs gathered popularity as fire retardants and in home and office furniture and electronics as they tend to burn slowly. In 1977 they were banned as some types of PCB - not the ones in the recent study - were proven to pose a serious health risk. The compounds persist in the environment, exist widely in the food chain entering our bodies and are also present in dust. It is also possible to pass them onto babies in the womb or when breastfeeding.

On the online Early Edition of Proceedings of the National Academy of Sciences in the USA, a study focused on abnormalities in rat babies whose mums were exposed to the toxic chemical in their diet during pregnancy and the early weeks of breastfeeding. The rat babies had a decreased ability to react to sound, as the chemical altered the part of the brain related to this. The levels of the chemicals in their blood on an equivalent scale was roughly that of the levels in the blood of human babies who were breastfed by mums exposed to high levels of the chemical from contaminated, high-risk environments.

The scientists who conducted the study, emphasised that their findings did not demonstrate that the toxicant causes developmental disorders, but are worried about the prevalence of this class of PCB - known as non-coplanar PCB's - in the atmosphere and environment, and the lack of studies into it.

The head of research, Dr Tal Kenet, who worked with Dr Michael Merzenich at the Keck Centre for Integrative Neuroscience at the University of California stated - 'there are chemicals out there, this being just one example, that could profoundly effect development'.

' This is a red Flag. The impact of this class of chemicals, whose toxicity has been under appreciated, must be studied in human populations - and fast. We know that some environmental risk applies on the early developmental history of the brain in the foetus and baby.People have struggled with what kind of factors these might be. I think environmental poisons, including the chemicals we've examined in this study are very good candidates,' Dr Merzenich said.

The team was not advising women to quit breastfeeding, Dr Kenet said. 'The finding does suggest the need for studies in human populations to determine whether there are possible risks associated with breastfeeding in cases of extreme exposure to this class of chemicals, in particular in infants who may have a genetic predisposition to developmental disorders based on their family history'

Editors comments:

Personally, I hope this study doesn't put women off breastfeeding. Or that they use it as an excuse not to breastfeed. We just need to clue ourselves up on this topic and not use/avoid chemicals wherever and whenever possible - whether they are considered safe or not! Breast milk is still superior. And those poor rats whom were tested - people can say a hundred times that they were bred for the sole purpose of testing but they still have feelings!