防かび剤の混合曝露によるマウスの次世代に及ぼす影響：TBZ濃度固定・IMZ濃度変動による効果

抄録

This study was aimed to re-evaluate the reproductive and neurobehavioral effects of maternal exposure to a combination of imazalil (IMZ) and thiabendazole (TBZ) with fixed-dose of TBZ in mice. IMZ/TBZ were given in the diet to provide levels of 0%/0% (control), 0.0015%/0.018% (IMZ/TBZ), 0.006%/0.018%, and 0.024%/0.018% during the gestation and lactation periods. Selected reproductive and neurobehavioral parameters were measured in the F₁ generation. In behavioral development during the lactation period of the F₁ generation, cliff avoidance on PND 7 in male offspring was restrained in a dose-related manner. In the exploratory behavior of the F₁-generation offspring, the average time of rearing of males was lengthened in the high-dose group. In the exploratory behavior of the F₁-generation adult females, the number of rearing decreased in the high-dose group, the average rearing time increased in a dose-related manner, and the number of defecations increased in the high-dose group. In the spontaneous behavior of F₁ generation, the average speed of males was restrained in the high-dose group, and the parallel lines of the control and treatment groups indicated a significant distance in the average time of rearing in the F₁-generation females. The low-dose level of IMZ was based on NOAEL of IMZ, and the fixed-dose level of TBZ was based on three-fold of NOAEL of TBZ. However, estimated IMZ/TBZ intakes from diets are lower than 1/400 and 1/2000 of ADI (0.03/0.1mg/kg/day). It seems unlikely that dietary intake levels of IMZ and TBZ produce neurobehavioral effects in humans.