甲醛及苯系物混合暴露对小鼠肺脏的氧化损伤作用

为探讨甲醛、苯、甲苯及二甲苯混合气体急性暴露对小鼠肺脏的氧化损伤作用,选用雄性健康昆明种小鼠50只,随机分为对照组和4个染毒组。染毒组1到4中甲醛、苯、甲苯和二甲苯浓度依次为:1.0+1.1+2.0+2.0μg·L-1、3.0+3.3+6.0+6.0μg·L-1、5.0+5.5+10.0+10.0μg·L-1、10.0+11.0+20.0+20.0μg·L-1,各染毒组混合气体的浓度分别是我国室内空气质量标准(GB/T18883-2002)的10、30、50和100倍。用静式吸入染毒方式,每天染毒2h,共染毒10d,实验结束后,测定小鼠肺脏中的氧化损伤指标。结果表明:染毒组小鼠的体重增加幅度均低于对照组,肝脏和脾脏系数显著低于对照组,肺脏ROS、MDA含量随染毒剂量的增加而增加,T-AOC、GSH、CAT、GSH-Px及SOD活力随染毒剂量的增加而降低,并且ROS、MDA含量与混合气体的浓度呈显著的正相关关系,GSH含量与混合气体的浓度呈显著的负相关关系。研究结果显示,甲醛、苯、甲苯及二甲苯混合气体急性暴露对小鼠肺脏具有氧化损伤作用,混合气体的联合毒性效应强于单一组分,ROS、MDA和GSH可以作为评价VOCs急性暴露对机体氧化损伤作用的敏感生物学标志。

Oxidative Damage Induced by Formaldehyde and Benzene Series Inhalation on Mice Lung

To study the oxidative damage on mice lung induced by acute inhalation of formaldehyde,benzene,toluene and xylene, 50 Kunming male mice were randomly divided into one control group and four exposure groups. Concentrations of formaldehyde,benzene,toluene and xylene of exposure group 1 to 4 were: 1.0 +1.1 +2.0 +2.0 μg·L-1, 3.0 +3.3 +6.0 +6.0 μg·L-1, 5.0 +5.5 +10.0 +10.0 μg·L-1, 10.0 +11.0 +20.0 +20.0 μg·L-1, respectively,which corresponded to 10,30,50,100 times of indoor air quality standard (GB/T 18883|2002). Mice were exposed to mixture of VOCs in a static cabinet for 10 days, which exposed VOCs for 2 hours per day, and then oxidative damage markers were measured. The results show that the increase of weight of mice exposed to VOCs was lower than that of the control group. The liver and spleen coefficient of mice in exposure groups were significantly lower than that of the control group. Exposure dose rising, contents of ROS and MDA increased, activity of T|AOC, GSH, CAT, GSH|Px and SOD decreased. ROS and MDA contents were significantly positively correlated to, while GSH content was negatively correlated to it. Thus, it was deduced that acute inhalation of formaldehyde, benzene, toluene and xylene cause oxidative damage on mice lung. Moreover ,the joint toxic effect is stronger than single gas. ROS, MDA and GSH can be used as oxidative damage sensitive biological markers to evaluate acute toxicity of VOCs .