My struggles with Queensland Fruit Fly in my apples and tomatoes got me thinking. How do they control the little blighters commercially?
So I did some reading, and I’m deeply uncomfortable with the results.
I’m not a scientist, and I know that it is easy to get the heebie-jeebies about things that sound scary because you don’t understand them. I was trying to keep an open mind.
But here’s what I found:
Up until September 2011, tomatoes in fruit fly affected areas of Australia (including Bowen, Bundaberg and South-East Queensland) were sprayed several times during the season with the insecticide dimethoate (also known as Rogor and Lebaycid). They were also dipped post-harvest in the chemical to kill any remaining fruit fly inside the tomatoes. I believe that this was mostly for export purposes, so tomatoes could be sent to New Zealand (where they don’t have fruit fly).
Dimethoate is a systemic insecticide. That is, it is absorbed by the plant and affects the plant tissue. The buggies bite the plant and die, so it’s really affective, but worryingly, it cannot be washed off.
In September 2011 it was determined that the levels of dimethoate could exceed the levels that were considered safe. The Australian Pesticides and Veterinary Medicines Authority (APVMA) therefore suspended its use in tomato (and many other food crops). It is still allowed to be used pre-harvest before fruit set for fresh tomatoes, and pre-harvest with a 21 day withholding period on tomatoes for processing.
My concern is : Why was this chemical OK last year and under a cloud of suspicion now? I understand that this suspension is a measure of caution and that a large margin of safety is built into the recommended public health standard, but seriously (now I’m losing my composure) why were we eating tomatoes dipped in toxic stuff that will kill a bug on the INSIDE?
References :
http://www.apvma.gov.au/products/review/current/dimethoate_faq.php
http://www.rirdc.gov.au/programs/established-rural-industries/pollination/tomatoes.cfm
500m2 in Sydney 