ASSESSMENT OF BIODEGRADATION OF WATER-INSOLUBLE POLYMERIC MATERIALS IN AEROBIC AND ANAEROBIC AQUATIC ENVIRONMENTS

In this study several recently developed or modified tests for assessi ng biodegradability of water insoluble polymers in the aquatic environ ments are described and compared. By modifying the traditional single- phase closed bottle B.O.D. test, lower deviations and a higher rate of oxygen demand were obtained. Biological oxygen demands in the two-pha se (semi-) closed bottle B.O.D. test correlated well with carbon conve rsion to inorganic gases under both, aerobic (modified Sturm test), an d anaerobic circumstances (anaerobic digester test). The test methods presented in this report can be used to assess the extent and rate of biodegradation of a vast range of synthetic and natural insoluble poly mers, varying from persistent (non-biodegradable) polyethylenes and sl owly degradable modified starch materials, to fully biodegradable natu ral polymers of plant origin.