Novel Daphnia Test For Detecting Chemical Pollution

Abstract

Daphnia magna (water flea) is perhaps the most commonly used test organism. As they represent primary consumers in freshwater aquatic ecosystems, their relevance in screening bioassays is very high. However, performing the standard Daphnia mortality test requires a 24–48 h exposure time, therefore no rapid response can be acquired on the risk posed by any environmental contamination. A novel bioassay has been elaborated and tested in our laboratory, using the above mentioned Daphnia species, but based on another ecological effect, the inhibition of feeding activity. Applicability and sensitivity of the test was assessed using potassium dichromate. Standard Daphnia test was also carried out as reference. The sensitivity range of the new method was similar to the reference test (EC₅₀ was in the same magnitude in comparison to Daphnia magna mortality test). Its further benefit is that this bioassay is using a sublethal endpoint.