engleski

Specific requirements for quality assurance in biodegradability and ecotoxicological testing

Biodegradability and ecotoxicological testing have a central position in the assessment of possible environmental impact of a material to be released into the environment. Compared to conventional chemical analysis, for both biodegradability and ecotoxicological testing, it is not possible to define “true” or “reference” method for a number of factors which can influence the test results. In fact, it is necessary to have a sufficient number of different, as much as possible standardised test methods, to allow the choice of the best method for the specific requirement. It should be pointed that, although standardisation of test conditions is, in general, possible, there are some parameters not amenable to standardisation. Therefore, the reproducibility of the test results using different methods or test conditions, or even using the identical test methods can be low. Furthermore, in general, it is not possible to achieve very high precision of biodegradability and ecotoxicological testing. From the afore-mentioned, it is clear that the choice of appropriate, well validated methods is essential for producing reliable and relevant biodegradability and ecotoxicological data. In this respect, the use of ISO and CEN standards, which are produced by collaborative study and standardisation bodies, is recommended. Even when using these carefully validated methods, care should be taken to provide specific requirements for quality assurance, and specific controls need to be applied to verify that the method is performing in the way as expected. Thus, in routine biodegradability testing, the following controls are recommended to be performed with every batch of the samples: a) procedure control, to check the activity of the inoculum; b) toxicity control, to check the possible inhibitory effect of the test material on the inoculum; c) abiotic control, to check whether or not the test compound is undergoing a degradation process by physico-chemical mechanisms, and d) adsorption control, to check possible adsorption processes of the test material. To ensure specific requirements for systematic quality control in the basic level ecotoxicological testing, careful checking of the sensitivity of test organisms and strict verification of the application of the test procedure should be carried out. In all these checkings, the rules of good laboratory practice should be strictly followed.

quality assurance; biodegradability; ecotoxicological testing

nije evidentirano