Petri Disk Screen

Few methods have been established in solid media. Two types of test can be distinguished, one dealing with model solid media (Petri disk screen), the other, closer to real conditions, dealing with soil or compost. 

Petri dish tests are more likely to give an estimate of primary bio degradability than ultimate biodegradability these tests give an estimate of the resistance of plastic to microbiological degradation and the clear zones do not necessarily show the complete consumption of the material but degradation of the polymer bonds. 

The advantage of these tests is that, in a single Petri dish, several materials (up to 10) can be studied under the same conditions. 

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