Innovative TIE approach based on algal sentinels to clean up waterways

CSIRO scientists have developed an innovative procedure for identifying and removing toxicants from estuarine and coastal waters using highly sensitive algae as toxicity test subjects.

The Toxicity Identification and Evaluation (TIE) procedure uses algal sentinels that provide a sensitive measure for toxic contamination that affects life further up the food chain, according to a report published by the Commonwealth Scientific Investigation & Research Organisation (CSIRO) in Australia (www.csiro.au). The TIE procedure reveals the class or related group of chemical compounds causing the damage and overall toxicity level. Successful tests of the procedure has attracted additional funding for research and development from major mining companies.

One early successful application of TIE revealed that the source of toxicity in offshore discharge from Melbourne Water’s Eastern Treatment Plant for sewerage was ammonia. This enabled the authority to engineer an effective removal. Melbourne Water’s project manager in Marine and Treatment Techno-logy Research, David Gregory, says TIE has quickly become a very useful tool for identifying classes of toxic compounds in effluents: “Knowing the general chemical properties of these substances helps us identify their source and origins, and provide treatment to remove them or prevent them getting into discharge in the first place.”

The director of CSIRO’s Centre for Environmental Contaminants Research, Dr. Graeme Batley, reports that the TIE procedure can provide a more comprehensive ecological health report than, for example, the US Environmental Protection Agency’s procedure, which only targets higher order organisms like fish.