Alison Bleaney
Letter to Minister for Primary Industries and Water David Llewellyn on Water Quality and Pesticide Monitoring in Water Catchments
November 17
THANK you for your letter of 7 November 2006 replying to my letter to the Premier regarding the Pesticide Monitoring in Water Catchments Program.
Many of the points in my letter remain unanswered, including that of the processes that are followed when a pesticide is detected in river water.
However you have raised some interesting points:
According to your letter the Rubicon River has been consistently polluted by simazine for over two months, with detectable levels at a number of sites along the river. You have determined that it has come from a forestry operation using pesticides according to “best practice”.
Given that an operator has clearly polluted the river water according to “best practice”, what processes have you put in place to stop this pollution and prevent this from recurring?
Control of use of pesticides is a State responsibility regardless of whether or not pesticides are applied according to label directions, as required by law.
Low level pesticide contamination above the guideline value but below the detection limit (as for 2,4-D, one of the major constituents of Agent Orange along with dioxin) is unacceptable for the water users of a river, especially when the monitoring program occurs only randomly each quarterly.
The nature and extent of the impact of agricultural and forestry pesticide usage on Tasmanian water quality can only be evaluated when full risk assessments of catchments including chemical audits are undertaken and the ANZECC (The Australian and New Zealand Environment and Conservation Council) water quality guidelines are fully followed.
Otherwise the ecosystems and all water users are exposed to an unquantifiable risk of water pollution.
The dates given for the flood monitoring of the George River do not correlate with closure of the oyster leases in Georges Bay, due to rainfall events. This is rather difficult to understand and does raise doubts about the reliability of the results of the flood monitoring program.
You state that the monitoring program is not designed to account for total pesticide load and will not take into account highly adsorbed and toxic pesticides e.g. alpha-cypermethrin and glyphosate. This revelation almost two years into the program is rather perplexing. Where was/is it stated that the Pesticide Monitoring in Water Catchments program was only to test water soluble pesticides with particulate matter removed and that this would allow for drinking water quality to be determined?
How then can water users (agriculture, aquaculture, and those that draw water directly from the rivers) have any confidence or place any reliability in this system? The same question applies to water bodies that manipulate their water during filtration and storage to produce drinking water.
The Australian Drinking Water Guidelines state that pesticides (toxic chemicals designed to kill or harm living organisms) are not to be found in drinking water and that guideline and health values are not just there to allow water to be polluted up to that level and that once detected, processes should be put in place to remove that source of pollution.
The public need to know whether this is a monitoring program designed only to allay fears and provide consumer confidence in water quality or whether it is designed to determine pesticide contamination and to take appropriate action if and when it is found. The two are not necessarily synonymous.
I look forward to your response.
Yours sincerely
Dr Alison Bleaney OBE
MBChB FACRRM
Binalong Bay, Tas 7216
Cc The Premier, Mr P Lennon.
Peg Putt MP
Will Hodgman MP
David Llewellyn’s November 7 letter
Dear Dr Bleaney
Thank you for your letter to the Premier of 8 September 2006 concerning the Department of Primary Industries and Water’s water-monitoring program for pesticides.
This program is helping to develop a greater understanding of the broad impact of agricultural and forestry pesticides usage on water quality in Tasmania. Positive detections from the baseline program are followed up with further sampling and investigation, to determine the likely source of contamination, where possible.
Follow-up testing after the July 2006 round of testing found no herbicide residues in the Brid, Jordan or Duck rivers. Residues of simazine continued to be found at a number of locations along the Rubicon River. The latest results to hand show some low-level residues remaining at 14 September 2006. The highest result of 1.1 parts per billion was recorded at a site near Parkham on 28 August 2006. Analytical results from further testing in late September are not yet available.
The investigation of this matter has identified a particular forestry operation as the likely source. However, the ground-based spraying operation at that site appears to have been conducted in accordance with the product label directions, as required by law.
An adverse experience report is being prepared for the Australian Pesticides and Veterinary Medicines Authority to provide feedback to the registration authority on the impact of pesticides usage.
Results from the flood-monitoring program are collated and published in a batch at around the same time as the results from the quarterly baseline monitoring program. I am informed that the latest batch of results was sent for publication on 8 September 2006, so they may not have been published at the time of your writing.
You have some concerns that the total pesticide load is not being measured. That may be true if there is significant off-site movement of soil from sites treated with highly absorbed pesticides. However, the program is not designed to account for the total pesticide load; only that fraction in solution, which is typically available for drinking water.
The laboratory methods for determining the range of pesticides that is determined in this program compromises the detection limit for 2,4-D to some extent. However, the detection limit of 0.2 ppb is still a low figure, considering the health value in the Australian Drinking Water Guidelines and the World Health Organisation drinking water quality guideline value of 30 ppb, for instance. I don’t believe the 2,4-D detection limit has any real impact on the relevance of the program.
Thank you for raising your concerns about the pesticide-monitoring program. However, I believe the broader community can and does have confidence in the transparency of the program and its role in further understanding the nature and extent of the impact of chemical use in primary industries on Tasmanian water quality.
Yours sincerely
David Llewellyn MHA
MINISTER FOR PRIMARY INDUSTRIES AND WATER
