Studies on the sorption of organochlorine insecticides by flour stored on or near treated laminated timber or plywood as used in freight containers

Wood preservatives containing a number of organochlorine insecticides, including aldrin, dieldrin, chlordane and lindane, have been approved in Australia for treating timber used as structural components in cargo containers. Studies on the migration of these insecticides from treated laminated timber and plywood, using commercial containers and in the laboratory, are reported here. The highest insecticide residue levels were found in flour samples stored on newly treated laminated sawn timber. Physical pick-up of insecticide from the surface of the floor was considered to be the major source of contamination. Sorption of insecticides from the atmosphere of the container was the most likely source of contamination in samples stored on or near treated plywood.