Combined evaluation of durability and ecotoxicity: A case study on furfurylated wood

Modified wood is commercially available and merchandized as a new, environmentally friendly and durable wood species. However, there are no standards focusing on the evaluation of modified wood. Combining resistance against fungal decay and good ecotoxicological properties may be a start. In this study softwood and hardwood species were furfurylated using different treatment processes and treating solutions. The durability was determined by exposing the treated wood to a range of Basidiomycetes and the ecotoxicity was studied on two aquatic organisms. It was the purpose to come to a strategy for how to unite efficacy and ecotoxicity, since this is important in product development. The results show that the selection of fungus used for mass loss determination and the choice of ecotoxicity method is decisive, confirming that a combination of methods is valuable. A tiered approach to find the optimal treatment seems the best option. First, adequate protection against wood-rotting fungi should be attained, followed by ecotoxicity evaluation of the wood leachates. If necessary, the optimization process should be repeated until both durability and ecotoxicity are within satisfactory limits. This process could be extended with other evaluation criteria, e.g. dimensional stability of the modified wood or a risk analysis of its leachate.