COHIBA newsletter: Hazardous substances in treated waste waters

The project COHIBA (Control of hazardous substances in the Baltic Sea region) has released a newsletter to present i.e. results of the vast water sampling programme.

The COHIBA project has detected traces of 11 hazardous substances in treated waste waters discharged to the Baltic Sea area. Although none of these compounds is acutely toxic to aquatic organisms at the measured concentrations, the results of the water sampling programme indicated some toxic effects in treated effluents. However, it is not possible directly to blame on these 11 analysed compounds for the harmful effects, and in the respect of these compounds the reason for toxicity leaves inexplicable.

The COHIBA project has screened municipal and industrial wastewaters, landfill leachates and storm waters in eight Baltic Sea countries. Up to 240 water and sludge samples were taken during one year. The project has performed biological tests to survey the acute and chronic toxicity of these waste waters, as well as chemical analyses to identify nine organic substances or substance groups and two heavy metals listed as being of concern in the Baltic Sea.

The newsletter head lines are:

• Hazardous substances in treated waste waters
• Whole effluent toxicity testing enhances waste water control
• Training to commence
• Choosing the best ways to reduce emissions

Download the COHIBA newsletter 1/2011