Wednesday, 13 July 2011

Chlorinated byproducts and autism

Brick Township in New Jersey (USA) enjoys a few accolades. According to the 2003 FBI statistics, Brick Township was the 2nd safest place to live in America. It also features highly in terms of its educational provisions and is generally seen to be quite a nice place to live. Like every other place, Brick Township (BT) does however also enjoy a not-so-enviable part of its community. In the case of BT it is its history with landfill and in particular French's landfill.

Landfill is a world-wide issue in terms of the staggering amounts of waste we as a population produce and what we do with it. We, here in the UK, are unfortunately particularly wasteful still, having previously been dubbed the 'landfill dustbin of Europe'. We are getting better I might add, but still that label persists.

French's landfill in BT has been in the US Environmental Protection Agency's sights for quite a few years. So much so that there is a dedicated EPA entry on their website showing the various strategies and progress being made in cleaning up French's landfill.  It makes for unpleasant reading in terms of the types of contaminants identified and the history of potential contamination from the site.

The reason for my interest is this paper which has recently appeared in the journal NeuroToxicology. The paper by Guariglia and colleagues appears to question the outcomes from a previous report on BT drinking water and the occurrence of autism (which can be read here). They undertook to examine how water treated with compounds similarly detected in the BT municipal drinking water supply might affect specific breeds of mice. The compounds in question were trihalomethanes (THMs) and perchloroethylenes (PCEs) which carry some pretty significant risks following continued exposure including being carcinogens. The mice (and their mothers) were given the contaminated water both whilst pregnant and post-natally.

The findings, bearing in mind that this is a study based on a mouse model:

  • Male mice seemed to be affected more by the cocktail given.
  • Behaviours indicative of anxiety were increased. 
  • Vocalisations in response to being separated from mother mouse were decreased. 
  • Social behaviours were reduced.

I appreciate that undertaking such studies on mice is not really to anyone's taste. Even though mouse models are used widespread in science (including autism research) it doesn't necessarily make it right. Keeping the ethical aspects in mind, the results deliver some very interesting leads. Interesting because of the various associations made and how they link with quite a few aspects of autism including the gender preference. Of course, correlation does not imply causation.

This is not the first time that BT has cropped up on the autism research radar. Readers may remember this study from a decade ago which hinted that BT might be a 'hotspot' for autism diagnoses. I remember quite a lot of the media interest in this at the time, and the various links being made between environment, the superior schooling provisions in BT, etc. to account for the results. Nowadays, autism spectrum prevalence rates of 0.6% look positively low compared to the emerging data.

I would like to see a little more study undertaken based on the recent mice findings. Population sampling for similar metabolites present in humans might be a good start, particularly in BT; for which various methods for analysing various biological mediums are available (indeed some very sensitive methods available). Given the amount of data amassed by the EPA within BT, I would assume some very powerful results could be produced to contribute to any 'cause or association' discussions that could follow, if only to discount any relationship.

To end on a slightly happier note, Brick Township is dealing with French's landfill. Hopefully with the completion of these clean-up operations in future months, BT can focus on its more beautiful assets and turn the page on landfill and its potential environmental effects.