Following the howls of anonymous outrage that followed my earlier article on this topic, after it was republished on CairnsBlog, I was lucky to have a chance to speak with someone who actually knows what he’s talking about.
Yesterday I had a phone conversation with Dr Jon Brodie, a water quality scientist based at James Cook University in Cairns. In what follows, I have tried to combine his information with my own commentary. Any errors in interpretation are my responsibility.
A knowledgeable man, Brodie has worked for more than a quarter century researching water quality issues. He has a grasp of what information on this topic is – and isn’t – available in FNQ.
Brodie was not effusive, but he was not reticent either. He was willing to answer questions and to mention relevant work undertaken by others.
I asked him quite specific questions about pesticide levels, possible conseqences, techniques for removing pesticides from drinking water, water quality guidelines and new work in the offing.
It appears there isn’t any data about pesticide concentrations in the Barron River – not in the public domain, at any rate.
Brodie believes the Barron is likely to contain traces of a wide range of pesticides, reflecting the diversity of cropping and other land uses in the catchment.
Organochlorines were banned in 1987. The newer generation of pesticides tend to be more short-lived, with half-lives in the order of one year. Some breakdown products, however, are also toxic and have their own breakdown pathways. The combined effects of different chemicals in this complex brew are another unknown.