The role of fungi in the production of chloroanisoles in general purpose freight containers

Samples of timber from the flooring of six general-purpose freight containers allegedly involved in the contamination of foodstuffs by 2,4,6-trichloroanisole were analysed for chlorophenol, chloroanisole and fungal content. All containers were found to be contaminated with 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol, pentachlorophenol and in all but one container their corresponding chloroanisoles. The concentrations of these compounds varied over a range of five orders of magnitude. In addition, 38 species of fungi were isolated from the timber. The species identified consisted of a variety of Alternaria (1), Aspergillus (7), Cladosporium (2), Eurotium (4), Mucor (1),Paecilomyces (1), Penicillium (16), Phoma (1), Trichoderma (4) and Ulocladium spp. No one species was found in all containers; however, Penicillium chrysogenum was isolated from five containers and six other species, Eurotium amstelodami, E. repens, E. rubrum, Penicillium corylophilum, P. aurantiogriseum and Ulocladium sp. were each found in three containers. Of the 38 species isolated, 19 are known to biomethylate chlorophenols in wood and pulped wood products. At least three species of fungi with this ability were found in each container. An attempt has been made to relate the presence of individual fungi in a container to the observed concentrations of the chloroanisoles.