Investigation of the biodegradability of water-insoluble materials in a solid test based on the adaptation of a biological oxygen demand measuring system

The usual BOD measuring systems used for monitoring the degradation of biodegradable materials are applied for the assessment of biodegradation exclusively in aquatic tests by detecting the amount Of O-2 consumed during degradation. In our study, a new, solid test application of a BOD system optionally capable to detect CO2 evolved during degradation is presented. After the optimisation of sample concentration and test temperature, the measurement set-up possessing relatively small reaction vessels of 250 ml with 80 g of soil mix proved to supply reliable and reproducible results. The system was optimised with microcrystalline cellulose-used as reference material in aquatic and solid test as well-showing 89.3 +/- 3.2% degree of degradation after 21 days, and it was applied for the assessment of biodegradation of commercially available non-powdered (films and kraft-paper) samples indicating degrees of degradation between 24.9 and 55.4%. (C) 2003 Elsevier Ltd. All rights reserved.