Compostable polymers ecotoxicity testing

The ecotoxicological impact of lactic acid-based polymers was evaluated by biotests, i.e. by the Flash test, measuring the inhibition of light production of Vibrio fisheri, and by plant growth tests with cress, radish, and barley [16]. Poly(lactic acid)s, poly(esterurethane)s 

It was stated that the Flash test is fast and a valuable toxicity test for pre-evaluation of the quality of compost, and it has been found to work well in composting studies. 

Standardized DIN tests using Daphnia magna and luminescent bacteria were apphed to assess the ecotoxicity of synthetic aliphatic-aromatic copolyester [18]. No significant toxicological effect was observed neither for the monomeric intermediates nor for the oligomeric intermediates. 

Ecotoxicity teste of compostable polymers are summarized in Table 7.6. 

The evaluation of the ecotoxicity of compostable polymers is an important issue to ensure that the produced compost is safe and causes no health hazards. 

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Ecotoxicity tests have been developed for the risk assessment of water pollution and contaminated soils. The main goal for ecotoxicological assessment of compostable polymers is to... 

Chapter 7 gives the definitions related to ecotoxicity testing, describes the currently used method and gives an overview of ecotoxicotogical assessment of compostable polymer materials. 

The inhabitants of the soil include the nematodes (the most numerous multicellular animals on Earth), oligochaetes (earthworms), arthropods (crustacea, arachnids, insects), and gastropods (snails). The ecotoxicity tests which have been mostly used to test the effect of biodegradable polymers on solid substrates (such as compost and soil) are the Earthworm Acute Toxicity Test, ISO 11268-1 [76] and the Daphnia (a widespread crustacean) Acute Immobilisation and Reproduction Test [77]. 

Figure 4.9 Average toxicity data obtained from laboratory composting tests in which natural and synthetic polymers have been degraded. Positive values are inhibitions negative values are increased growth or biological activity. Adapted from J.I. Fritz in Ecotoxicity of Biogenic Materials During and After their Biodegradation, University of Natural Resources and Life Sciences, Wien, Austria,...

The testing procedure is slightly different the Controlled Composting Test . DIN 54900 (in press) defines Biodegradable polymers and measures the ecotoxicity and heavy metal content. The method will be very similar to the CEN standard. 

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