Human activities place pressure on ecosystems
Aquatic and terrestrial ecosystems are under threat worldwide from contaminants released through human activities such as mining, agriculture, and urban and industrial development.
Ecotoxicology investigates the response of organisms to these contaminants in ecosystems. Ecotoxicity tests, also known as direct toxicity assessments (DTA), using sensitive organisms (e.g. microalgae, invertebrates) respond to the bioavailable fraction of contaminants. Ecotoxicology is an important line of evidence in environmental risk assessments, especially when linked to chemical measurements of contaminant bioavailability.
Increasingly, the application of ecotoxicity tests using a range of organisms from different trophic levels (food chain) is required. The challenge has been to develop new tests, preferably using local species that are sensitive to the contaminants of concern, that are robust, reproducible, and ideally rapid and inexpensive, and that represent the an environmentally relevant exposure of contaminants to organisms.
The suitability of ecotoxicity tools varies for different ecosystems, contaminants and industries, often requiring refinement or development of new methods to meet different assessment needs.
Developing the next generation of tools to rapidly assess toxicity
We apply, refine and develop new ecotoxicity tools and models for rapid quantification of biological effects and responses of organisms to contaminants.
For example, we have developed:
- Multispecies toxicity tests with microalgae to measure herbicide toxicity.
- Toxicity tests with tropical and temperate invertebrates (e.g. copepods) measuring reproduction to assess waters and sediments.
- Testing procedures to evaluate the response of organisms to short-term (pulse) exposures to contaminants.
- Toxicity identification evaluation (TIE) tests that identify contaminants causing toxicity to organisms.
Our new methods reduce uncertainty in environmental management decisions to safeguard water, sediment and soil quality, and contribute to a reduced environmental footprint from industrial, urban, mining and agricultural activities. Our quarantine approved ecotoxicology facilities enable testing to be carried out on samples originating from overseas.
We are increasingly using molecular, ecotoxicogenomic, in vitro and modelling tools to both reduce reliance on whole-organism testing and to better understand modes of action of contaminants and multiple stressors at the cellular, biochemical and molecular level.
Providing assessment solutions for industry and government
Our extensive ecotoxicology expertise is applied to assess contaminants from industrial, sewage, mining, oil and gas, chemical, pulp and paper and port activities in temperate, tropical and polar ecosystems, both nationally and internationally.
We undertake studies through all stages of development: from feasibility (environmental impact statements (EIS), environmental risk assessments (ERA)) to operating and legacy stages, to enable improved decisions for the management of discharges (e.g. industry and mine sites waters, or produced formation waters), and to develop clean-up goals for site closure and remediation. We derive water and sediment quality guideline values for improved management of contaminants ecosystems.
We maintain a range of bioassays using bacterial, algal, cladoceran, amphipod, bivalve, chironomid, copepod and snail species for application in fresh and marine waters and sediments.
Our ecotoxicology facilities are co-located and integrated with multi-disciplinary expertise in analytical chemistry, contaminant fate and transport, speciation, bioavailability, ecology and risk assessment, enabling the study of complex contaminant exposure scenarios requiring multiple lines-of-evidence for assessment.