Division of Toxicology, National Food Administration, P.O. Box 622, SE-751 26 Uppsala, Sweden.|Division of Toxicology, National Food Administration, P.O. Box 622, SE-751 26 Uppsala, Sweden.|Division of Toxicology, National Food Administration, P.O. Box 622, SE-751 26 Uppsala, Sweden.|Division of Toxicology, National Food Administration, P.O. Box 622, SE-751 26 Uppsala, Sweden.|Division of Toxicology, National Food Administration, P.O. Box 622, SE-751 26 Uppsala, Sweden.