Ecotoxicity of the Polymers

Dang and co-workers [82, 83], discuss the measurement of toxic effects of biodegradable polymers. Using a cell culture test system the authors demonstrated the functional suitability of the method with four samples. The results have been determined mainly by the presence of leachable substances, effects of non soluble polymers have not been 

The work of Stacker [65] has demonstrated that a direct measurement of the plant toxicity of biodegradable materials is impossible. Initiated degradation processes in the test trays had caused a dramatically reduced plant growth. Those effects appeared even if natural polymers, such as starch or cellulose were used and even if the soil was sterilised before the test. Tests with not readily biodegradable polymers should be possible since the microorganism community is not activated that much. In such a case ecotoxic effects will most probably be related to an incompatibility of leachable components from the material. That outcome should be considered for the conduction of bioassays with plants and with other test species as well. 

The earthworm Eisenia foetida) is definitely not suitable for determining the ecotoxicity of materials that are digestible by the animals. The feeding effect will result in an increased growth, which may more than compensate potential inhibition effects [65]. 

Aquatic bioassays made with elutriates from polymeric materials are possible although limited to water-soluble components. The elutrition procedure should be designed properly to simulate the conditions at the natural environment of the application. Examples could be the continuous elutrition in aquatic environments or a periodic exposure at times of 

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