APVMA are proposing to use a modified Canadian model as their basic tool for aerial spraying above 3m. This will allow them to give the go ahead to the forestry/plantation industries for a release height of 15m for aerially sprayed pesticides. Hitherto a release height of 3m has been used in official modelling processes, and this has been well documented to be inadequate to prevent contamination well beyond set boundaries.
APVMA are asking for public comment on their draft document, despite the fact that they currently can provide no modelling for a 15m release height. They also state that the label on the chemical used will state at what height the chemical can be released when sprayed. At present neither Astound Duo or Roundup, amongst many other chemicals, provide any release heights on their labelling. Will such chemicals be recalled for re-labelling?
Will the public be given access to information on those chemicals now being sprayed at a release height of 15m?
Why are chemicals being sprayed at 15m with no modelling available from APVMA, and their document still a “draft”, awaiting public comment?
Why are States and Territories spraying chemicals at heights that are not on the label in the absence of an Australian document to state that this is a safe practice?
How can this have happened and who will be held accountable when harm due to this practice is demonstrated?
Does the APVMA, the Registrar for Chemicals for Tasmania and the Health Dept. have a legislated duty of care to ensure safe practices?
Do the above bodies profess to adhere to the Precautionary Principle?
APVMA’s newly revised Spray Draft Report and contact details are available on www.apvma.org
And:
From: The Pesticide and Toxic Chemical News Journal.
Scientists tracking pesticide migration in Canada and the Northeast U.S. have found that precipitation frequency, degradation rates and region-specific oxidant concentration must all be factored when assessing whether a reactive, water-soluble pesticide will undergo long-range transport.
As published in the October edition of Environmental Toxicology and Chemistry, researchers from the National Water Research Institute of Environment Canada in Burlington, Ontario, and the University of Toronto at Scarborough sampled water from 30 lakes in Canada and the U.S. and tested for 27 common current-use pesticide (CUP) active ingredients. They frequently found 11 of the CUPs in lakes which received runoff from agricultural fields, but they also found them in lakes hundreds of kilometers from known application areas.
The most commonly found CUPs were the triazine herbicide atrazine and its desethylated degradation product; herbicides alachlor, metolachlor and dacthal; organophosphate insecticides chlorpyrifos, diazinon and disulfoton; organochlorine insecticides a endosulfan and lindane; and fungicides chlorothalonil and flutriafol. Six of the pesticides were determined to have empirical half-distances of 560 km to 1,820 km based on the water-concentration gradient at the given latitude.
Derek Muir, project chief for Atmospheric Contaminants Impacts, Aquatic Ecosystem Protection Research Branch at the National Water Research Institute in Burlington, Ontario, told Pesticide & Toxic Chemical News that although finding CUPs in remote lakes is not a new development, the research team appears to have found more pesticides than before. He credited Frank Wania and his students at the University of Toronto at Scarborough for developing new modeling techniques that may be considered to be the major contribution of the study.
“By adjusting the model parameters related to rainfall and atmospheric hydroxy radical concentrations, he was able to simulate the trends in regional and long range transport (or empirical half-distances) that we observed using lake waters,” said Muir. “Although long range transport (LRT) is not part of current new pesticide evaluation, with this work we are closer to having a tool which regulators and industry developers could use to evaluate LRT using the physical-chemical property data that is routinely generated for pesticide registration.”
The researchers attempted to predict the atmospheric long-range transport behavior using various computer modeling programs. The modeling efforts failed except when periods of lower hydroxyl radical concentrations and periods of low precipitation were factored into the algorithm. Using both model results and field observations, the research team was able to determine that given the relatively high latitude and low precipitation rates of south-central Canada, many CUPs have the potential to undergo regional-scale transport to reach lakes in areas relatively far-removed from the points of application.
— G. Jeffrey Hoch
Pesticide & Toxic Chemical News, October 25, 2004, Volume 33,
Number 1, Copyright © 2004, CRC Press LLC
Dr Alison Bleaney
St Helens
