Historically and even now, NZ has been a relatively heavy user of pesticides and other dangerous horticultural chemicals. It was also a big user of aerial top dressing. Peak use of pesticides occurred up to the 1960s, relatively uncontrolled. Restrictions on some of the most toxic (like DDT, organophosphates) began after that, and the outlawing of certain products accelerated with each decade and still continues.
So if these pesticides (and fungicides) were a cause of autism, we would have expected very high rates of AS in the 1950s here, and that the rates would progressively fall each decade after that.
However any relationship between pesticide use and AS here seems to go in the opposite direction - the fewer dangerous chemicals allowed, the higher AS rates have climbed.
There seems to be no doubt that some of the now banned chemicals were DNA disruptors generally though - the evidence for that is fairly good; it's just not convincing when proposed as causing AS.
NZ (unfortunately) manufactured Agent Orange and other herbicides for the USA which were designed to be toxic to people and plant life. The USA funded the factories and production here so that they could blitz Vietnam with these dangerous chemicals. Production was limited to one area only of NZ - a small town - where locals worked for the manufacturer (IvanWatkinsDow). Sadly, the passage of time has revealed an extremely high and unusual rate of cancer amongst the people who worked there, their offspring, and people who lived in that area generally. Of course this can't be replicated now by exposing a group to Agent Orange and withholding it from a control group; however nothing else appears to be as likely as Agent Orange in terms of an explanation for the magnitude of cancer deaths there.
Unfortunately some dangerous chemicals are still used here, though not ones as harmful as Agent Orange, DDT and 245T were.
14 Jun 2017, 12:31 am
