Burrlioz software

Burrlioz is standard software used to derive water quality guideline values for toxicants in Australia and New Zealand.

You can also use Burrlioz to derive default guideline values (DGVs) or site-specific guideline values, in conjunction with the derivation methodology using laboratory-effects data.

Burrlioz 2.0 and its user manual can be accessed on CSIRO’s Software portal. You will need to register for free and then log in to download the software.

How it works

The software fits a statistical distribution to an empirical cumulative frequency distribution of the input toxicity test data. This is commonly known as a species sensitivity distribution (SSD). From this, Burrlioz estimates the concentrations of a toxicant that would protect nominated percentages of species (level of protection) with median confidence.

Burrlioz 2.0 automatically uses:

  • a log-logistic distribution for datasets that comprise less than 8 toxicity values
  • a Burr Type III distribution for datasets of 8 or more toxicity values.

The data are input in Excel and stored as CSV (comma delimited values) files. This enables the toxicity data to be accompanied by matching metadata on species name or taxonomic group, with these being displayed as symbols or names on a coloured plot.

Custom options in Burrlioz

  • Show the agreed level of protection on the plot; a separate report shows the SSD plot, the input data and the guideline values for 99, 95, 90 and 80% species protection.
  • Plot the 95% confidence limits around the SSD curve.
  • Display symbols or species names on the plot (graphical SSD output shown in Figure 1).
Figure 1 Example of Burrlioz 2.0 graphical species sensitivity distribution output. The concentration for 95% level of species protection is indicated at the bottom of the curve.
Figure 1 Example of Burrlioz 2.0 graphical species

Development of the software

Burrlioz 1.0 was developed at CSIRO by Campbell et al. (2000) for the ANZECC & ARMCANZ (2000) guidelines. The software was refined by CSIRO in 2015.

The application is underpinned by statistical processing in the R open source programming language.


ANZECC & ARMCANZ 2000, Australian and New Zealand Guidelines for Fresh and Marine Water Quality, Australian and New Zealand Environment and Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand, Canberra.

Campbell, E, Palmer, M, Shao, Q, Warne, M & Wilson, D 2000, Burrlioz: A Flexible Approach to Species Protection, TIES/SPRUCE 2000 Conference, 4–8 September 2000, University of Sheffield, UK.