Biodegradability and waste behavior of industrial wood-based construction materials

Industrial wood-based construction materials: chipboard, plain and overlaid plywood, phenolic surface film, laminates and selected synthetic polymers were studied for their biodegradability under aerobic and anaerobic conditi ons and for the environmental quality of the degradation residue, The yield s of carbon dioxide plus methane from the wood-based materials in 6 months under anaerobic conditions at 33 degrees C ranged from less than or equal t o 3% to 79% compared to that obtained from starch, and under aerobic condit ions from less than or equal to 7% to 55% of that obtained from acetate, me asured in 28 days at 25 degrees C, The plywoods were more readily degraded under aerobic and anaerobic conditions, The microbes attacked mainly the S- 2-layer of the plywoods and started from the S-3-layer of the wood cells of chipboard in the compost, Extensive cavities, occupied with microbes, were observed by electron microscopy in the decaying plywoods, chipboard and la minates, The contents of Cu, Cr, Pb, Ni, and Cd of the wood-based construct ion materials were low, <10 mg kg(-1), compared to PVC and to a typical mun icipal solid waste. Toxicity and the amount of leachable organic halogen fr om the wood-based construction materials were low, EC50 of 4-8 g L-1 to V. fischeri and <12 mu g adsorbable organic halogen (AOX) of g(-1). The result s show that the wood-based construction materials studied were aerobically biodegradable and the plywoods also anaerobically, There was no toxicity to wards photobacteria or substances of environmental concern in the biodegrad ation and incineration residues of the materials tested.