Abstract
Information on the biodegradability of an oil product (or its components) is needed for classification and labelling purposes. The extent to which a product can be broken down by microbial attack is usually determined using a โready biodegradabilityโ test (e.g., OECD 301 Test Guidelines). However, these methods are stringent screening tests and can often underestimate the extent to which a product can be removed from the natural environment by biodegradation. CONCAWE (the European oil companiesโ organisation for environment, health and safety) has recently developed a test for determining the potential (or โinherent') biodegradability of oil products. This is often more useful for assessing the likely impact of an oil product in the event of its release into the environment. This paper gives examples of CONCAWE test results for a number of base fluids and formulated products, and compares these results with those obtained in a โready biodegradabilityโ test. Guidance is given on the applicability of data that has been obtained using the CONCAWE method.