READY BIODEGRADABILITY TEST IN SEAWATER - A NEW METHODOLOGICAL APPROACH

To estimate the persistence of xenobiotic in the environment, a new ul timate mineralization approach for assessing ready biodegradability in seawater has been developed, based on the OECD 301 B guideline for fr eshwater, A few changes in the currently accepted procedure have been made to adapt the test to seawater, The assays, realized with seawater as test medium and inoculum, give high variability results of biodegr adability, To lower this variability a synthetic marine medium joined to a highly concentrated inoculum from a marine aquarium filter have b een used, The results reveal (i) a decrease of variability, together w ith an increase in degradation rate of the tested chemicals due to a b etter control of inoculum and test medium, and (ii) no difference in e asy biodegradable compound (sodium benzoate) biodegradation rate when two marine aquarium inocula are tested, This study demonstrates that t he ready biodegradability test developed on synthetic marine medium an d inoculum from marine aquarium filter minimizes the effect of the sam ple location on the biodegradation results of compounds and allows cla ssifying chemicals as a function of their biodegradability. (C) 1995 A cademic Press, Inc.