关键词： Mixture   Vitamin deficiency   Pesticides   Real-life risk simulation   Hormesis   Open field test   Elevated plus maze test   Passive avoidance test  

摘要： We investigate the long-term effect of very-low dose exposure to a mixture of six pesticides associated with hydrophilic vitamin deficiency on the neurobehavioral outcomes of rats. Two hundred Wistar rats were divided into four groups, two control groups, a vitamin sufficient control group and a vitamin deficiency control group and 2 test groups, a vitamin sufficient test group, and a vitamin deficiency group. The test groups were exposed for 9 months to a mixture of diquat, imazamox, imazethapyr, tepraloxydin, bentazone and acifluorfen in doses of 0.01xNOAEL (mg/kg bw/day). After 9 months of exposure, the behavior changes were evaluated by open field test and elevated plus maze test and the memory was assessed by passive avoidance test. Chronic vitamin deficiency decreased locomotor and special orientation activity and increased anxiety-like behavior in rats. Exposure to very low doses of a mixture of 6 pesticides caused central nervous effects, manifested as decreased locomotor activity, and increased anxiety levels. Vitamin deficiency and low dose chronic pesticides mixture exposure thus affected the central nervous system, especially long-term memory.