DTA programme on track says EA

The programme is a collaborate research and development project aimed at trialling the application of DTA to controlling and monitoring complex mixtures of chemicals in discharges to water. Three sites were chosen for the first stages of the programme – the Rivers Esk, Aire and Tees.

Several lessons have been learnt so far from the programme including the importance of early screening of discharges for toxicity and subsequent targeting of environmental toxicity assessment to ensure resources are used cost-effectively. Synchronising toxicity assessment, biological, fisheries and chemical survey work was viewed as essential to make sure that the data available represented the current position. Difficulties with the culture of test organisms in waters of different hardness were encountered and further investigation will be carried out later on in the programme.

Poor correlation was reported between the results from the Daphnia ecotoxicological tests and those from the bioluminescence and chemiluminescence rapid ecotoxicological tests in the Esk project. The EA says this may suggest the need for a larger battery of rapid test methods.