The Pesticide Risk Metric Calculator

All concentration data must be in µg/L

For concentrations <LOR , the < must be in the same cell as the numerical values (not in separate columns). The PRM Calculator will treat <LOR data itself – there is no need for the user to treat these values.

If an abbreviation for a non-detect or trace value appears within your data, these must be changed to the lowest <LOR value for the associated pesticide. For example, a trace value for chlorpyrifos should be changed to ‘<0.02’ as it is the lowest LOR. This will vary depending on individual laboratories that run the samples.

Any character values in data will be replaced with empty cells.

Columns for all 22 reference pesticides must be present. If you do not have data for some pesticides, column cells can be left empty but the column must still exist.

Site names are spelled consistently throughout dataset. A misspelt site name will result in it being identified as a different site.

The smaller the number of individual data points, the lower the confidence will be in the wet season average.

The calculation of the wet season PRM involves the selection of a 182-day risk window that encompasses most of the wet season rainfall, the discharge, and in tropical regions, the period of greatest risk to aquatic ecosystems. This is a prerequisite for the GBR pesticide reporting. Where data sets for an entire sampling year exist and the wet season risk is required to be calculated, the user must upload a second CSV containing the first flush date for each site in the dataset. If there are multiple years for a single site, a first flush date will be needed for each site-year combination.

To ensure accurate reporting, consider the following points when calculating the wet season Pesticide Risk Metric (PRM):

First Flush Date:

This date should reflect when there is an increase in river flow or height and an increase in detectable pesticide concentrations. It should also precede an increase in the magnitude and frequency of ‘wet’ events to allow the 182-day exposure window to capture the period of elevated pesticide concentrations. If sampling was only conducted during the wet season / high risk period (182-day time period), this step can be skipped as the calculator will use all data available to calculate the wet season PRM.

Alternative Start Date:

If a sampling regime was used that is not centred around the wet season, the user can choose a date to start the 182-day exposure window for each site. If a first flush date is not supplied, the PRM calculator will evaluate the 'wet season risk' over the period covered by the uploaded data.

Consider Sample Size:

We advise caution around interpreting the wet season PRM if the number of samples within the exposure window is low. The lower the number of sampling days within the wet season exposure window, the less confidence there is in the wet season PRM and the full range of concentrations may not be reflected over the 182-day exposure window.

Please see the check-list below for an itemised list of requirements for your data upload

The results in the table below have been rounded to 1 decimal place as recommended in the user guide. The results in the download table will need to be rounded to 1 decimal place when reported. Additionally, it is recommended that results less than 0.1 are reported as “<0.1”. Please refer to the user guide for more information.

The results in the table below have been rounded to 1 decimal place as recommended in the user guide. The results in the download table will need to be rounded to 1 decimal place when reported. Additionally, it is recommended that results less than 0.1 are reported as “<0.1”. Please refer to the user guide for more information.

The Wet Season Average will only be calculated for sampling years where a site contains at least 3 separate days of data within the sampling year of interest.

If plots do not appear please ensure that the "Explore Wet Season Plots" button on the Wet Season Table tab has been selected.

WQI PRM Calculator: Water Quality & Investigations (2024) Pesticide Risk Metric Calculator, Department of the Environment, Tourism, Science and Innovation, Brisbane, Australia

Method paper for estimating PRM: Warne MStJ, Neelamraju C, Strauss J, Smith RA, Turner RDR, Mann RM. 2020. Development of a method for estimating the toxicity of pesticide mixtures and a Pesticide Risk Baseline for the Reef 2050 Water Quality Improvement Plan. Brisbane: Department of Environment and Science, Queensland Government.

No data uploaded to this application is saved or recorded. It is purely for the user.

The information presented in this application is from several sources and, as such, does not necessarily represent government or departmental policy.

While every care is taken to ensure the accuracy of this information, the Department of the Environment, Tourism, Science and Innovation makes no representations or warranties relating to accuracy, reliability, completeness, currency or suitability for any particular purpose and disclaims all responsibility and all liability (including without limitation, liability in negligence) for all expenses, losses, damages (including indirect or consequential damage) and costs that might be incurred as a result of any use or of reliance on the information and calculated data in any way and for any reason.