2011/2023: Pioneer River at Dumbleton Pump. Pesticides: Multiple

Pioneer River at Dumbleton Pump (Mackay Drinking Water Supply)

July 7 2023: https://www.foe.org.au/are_queenslanders_microdosing_on_weedkillers_in_their_drinking_water

5646 pesticide detections between Sep 2011 and Jan 2023

Diuron: 779 detections of Diuron between Nov 2011 and Jan 2023. 6.5ug/L (max 11/1/14). 0.5076ug/L (av.)

2,4-D: 493 detections of 2,4-D between Jul 2012 and Jan 2023. 3.7ug/L (max 11/1/14). 0.1512ug/L (av.)

Ametryn: 265 detections of Ametryn between Dec 2011 and Jan 2023. 0.6ug/L (max 24/1/13). 0.0409ug/L (av.)

Atrazine: 732 detections of Atrazine between Sep 2011 and Jan 2023. 5.1ug/L (max 29/1/20). 0.5265ug/L (av.)

Bromacil: 98 detections of Bromacil between Sep 2011 and Jan 2023. 0.71ug/L (max 6/7/22). 0.0316ug/L (av.)

Chlorpyrifos: 6 trace detections of Chlorpyrifos between May 2022 to July 2022.

Diazinon: 8 trace detections of Diazinon between Jan 2017 to July 2022.

Fluroxypur: 308 detections of Fluroxypur between Feb 2014 to Jan 2023. 0.6ug/L (max 4/1/21). 0.1235ug/L (av.)

Haloxyfop: 4 detections of Haloxyfop between Nov 2016 and Mar 2023. 0.06ug/L (max 23/2/20). 0.023ug/L (av.)

Hexazinone: 662 detections of Hexazinone between Dec 2011 and Jan 2023. 1ug/L (max 1/1/13). 0.1529ug/L (av.)

Imazapic: 412 detections of Imazapic between Feb 2015 and Jan 2023. 0.58ug/L (max 5/1/17). 0.0762ug/L (av.)

Imidacloprid: 562 detections of Imidacloprid between Feb 2012 and Jan 2023. 1.4ug/L (max 4/1/21). 0.151ug/L (av.)

Isoxaflutole: 277 detections of Isoxaflutole between Jul 2012 and Jan 2023. 0.19ug/L (max 6/2/22). 0.0453ug/L (av.)

MCPA: 360 detections of MCPA between July 2012 and Jan 2023. 0.87ug/L (max 9/1/19). 0.0651ug/L (av.)

Metolachlor: 406 detections of Metolachlor between Nov 2011 and Jan 2023. 0.37ug/L (max 29/1/20). 0.0497ug/L (av.)

Metsulfuron Methyl: 26 detections of Metsulfuron Methyl between Jan 2015 and Feb 2020. 0.04ug/L (max 31/1/17). 0.0141ug/L (av.)

Metribuzin: 169 detections of Metribuzin between Jan 2013 and Jan 2023. 0.9ug/L (max 7/1/13). 0.0742ug/L (av.)

Simazine: 13 detections of Simazine between Feb 2012 and Jan 2020. 0.02ug/L (max 1/2/17). 0.011ug/L (av.)

Tebuthiuron: 10 detections of Tebuthiuron between Jan 2021 and Mar 2021. 0.12ug/L (max 2/4/18). 0.03ug/L (av.)

Terbuthylazine: 35 detections of Terbuthylazine between Dec 2020 and Mar 2021. 0.22ug/L (max 15/1/23). 0.0383ug/L (av.)

Triclopyr: 20 detections of Triclopyr between Dec 2012 and Jul 2022. 0.28ug/L (max 31/12/21). 0.0506ug/L (av.)

Source: Pesticide Reporting Portal – Queensland Government. https://storymaps.arcgis.com/stories/c0f0c6d7d88a4fd3a5541fe59f41ff75


Ian White1, Jon Brodie2 and Carl Mitchell3
1. NRM, Mackay, 2. ACTFR, James Cook University, Townsville, 3. Healthy Waterways Program, Mackay
“Residues of five herbicides were found at Dumblet on Weir during the event. Pesticides found were diuron, ametryn, atrazine, hexazinone and 2,4-D. Deset
hylatrazine, a degradation product of atrazine, was also recorded on the rising stage of the hydrograph. Concentrations of all of these pesticides were highest during the initial runoff and became diluted as the event progressed. No filtered samples were collected for the analysis of pesticides, therefore it is unknown what proportion of these chemical residues were carried on the sediment and how much was in solution …”
Dumbleton Weir detections (Ranges)
Diuron: 8.5ug/L – 0.9ug/L
Atrazine: 1.3ug/L – 0.29ug/L
Desethylatrazine: 0.1ug/L – 0.05ug/L
Hexazinone: 0.3ug/L – 0.11ug/L
Ametryn: 0.3ug/L – 0.1ug/L
2,4-D: 0.4ug/L – 0.2ug/L


Pioneer River at Dumbleton Pump Station

Ametryn 28kg, Total Atrazine 460kg, Diuron 440kg, Hexazinone 93kg

Land Use Yield

Ametryn (Sugarcane) 0.091 kg/km2

Atrazine (Cropping, Forestry & Sugarcane) 0.68kg/km2

Diuron (Cropping, Horticulture & Sugarcane) 1.4kg/km2

Hexazinone (Cropping, Forestry  and Sugarcane) 0.079kg/km2

Source: Reef Water Quality Protection Plan. Total Suspended Solids, Nutrients & Pesticide Loads (2012-2013) for Rivers that Discharge to the Great Barrier Reef – Great Barrier Reef Catchment Loads Monitoring 2012-2013


An evaluation of the prevalence of alternate pesticides of environmental concern in Great Barrier Reef catchments: RP57C 2014
Rachael A Smith, Ryan Turner, Susi Vardy, Rae Huggins, Rohan Wallace, Michael St.J. Warne
Water Quality and Investigations, Environmental Monitoring and Assessment Sciences, Science Division, Queensland Department of Science, Information Technology, Innovation and the Arts.

Pioneer River at Dumbleton Pump

Pesticides: Ametryn, Atrazine, Diuron, Hexazinone, 2,4-D, MCPA, Triclopyr, Isoxaflutole, Fluometuron, Metribuzin, Simazine, Metolachlor