居室装饰所致有害化学物毒性的联合作用研究

发布时间：2018-11-24 18:58

【摘要】：平均每人一天当中有80%以上的时间是在室内环境度过的,室内空气质量的好坏直接关系着人们的健康。随着人民生活水平的提高,居室装饰成为普遍现象,由居室装饰所致的室内空气挥发性有机化合物的污染大量增加。而且由于建筑保温绝热的需要,室内通风状况愈来愈差,有害气体污染浓度愈来愈高,从而导致室内污染问题日益严重。在现有的卫生标准中,只有单一污染物的浓度限值。当有两种或两种以上污染物同时存在时,若掌握其联合作用的资料,就能对其健康危害作出比较确切的评价。本研究首先对南京市区新装修的居室进行了室内空气污染状况调查,在监测结果基础上进行一般毒理学和细胞毒理学实验,研究室内空气中几种主要挥发性有害化学物毒性的联合作用,并采用分子生物学技术探讨苯与甲醛致细胞遗传毒性的联合作用,以及其可能的氧化损伤机制。污染状况监测结果显示:新装修后居室内空气中的污染物主要有氨、甲醛、苯、甲苯、二甲苯以及乙苯,其中氨、甲醛、苯、甲苯、二甲苯超标,1h平均浓度的超标率和最大超标倍数分别为77.78%,93.02%,52.78%,37.50%,26.47%及67.5倍,37.9倍,2.6倍,10.0倍,21.5倍。通过小鼠静式吸入染毒测得单一或混合化学物的LC50,同时按公式计算其混合物LC50的预计值,根据混合物的LC50预计值与实测值的比值Q值,按Smyth法评价其联合作用方式。结果显示:在本实验条件下,按照现场监测结果的实际比例,苯与甲醛,甲醛与氨,苯、甲醛与氨,混苯与甲醛共同存在时,其联合作用表现为相加作用;而苯与氨共存时,其联合作用方式表现为拮抗作用。在体外细胞培养实验中,首先检测了经苯或/和甲醛染毒24h,对原代大鼠肺成纤维细胞及CHL细胞生长的影响情况,计算其细胞生长半数抑制浓度(IC50),根据IC50的预计值和实测值的比值Q值,按Smyth法评价其联合作用方式。从实验结果中发现,甲醛的细胞毒性大于苯,两者的细胞生长半数抑制浓度(IC50)不在一个数量级。在苯与甲醛共同作用于原代大鼠肺成纤维细胞时,若甲醛的剂量远大于苯(其比例关系为26∶8),其联合毒性作用表现为相加作用,而当甲醛与苯以等毒性剂量染毒时,则其联合毒性作用表现为协同作用。同时,苯与甲醛以等毒性剂量共同作用于体外培养CHL细胞时,其细胞毒性联合作用也表现为协同作用。通过正交实验设计,研究苯与甲醛致体外培养细胞遗传毒性的联合作用,以及其可能的氧化损伤机制。前者实验观察指标包括细胞凋亡、DNA-断裂与DNA-交联,后者实验观察指标有MDA水平、GSH水平与SOD活性。正交实验方差分析结果显示:苯、甲醛均可以导致体外培养细胞DNA-断裂以及细胞凋亡率、DNA-交联率增加,MDA生成增加、SOD活性与GSH水平下降,其DNA损伤的程度趋势与氧化损伤的程度趋势一致;当苯、甲醛同时作用时,致细胞遗传毒性作用加重,且在DNA损伤与氧化损伤上均具有统计学交互作用(P0.05),从实验结果效应图可以看出,在一定的剂量范围内,曲线随剂量增大而远离,这种交互作用是协同作用。本研究认为,室内空气挥发性化学物可产生联合毒性作用,其主要联合作用方式表现为相加作用。而苯与甲醛甚至可能产生协同的细胞毒性作用及细胞遗传毒性作用。为了更好地保护人们的身心健康,建议在制订苯与甲醛共同存在时的室内空气卫生标准时,其浓度限值应比现有的标准值要小。
[Abstract]:An average of more than 80% of the day is spent in the indoor environment, and the quality of the indoor air is directly related to the health of the people. With the improvement of the living standard of the people, the room decoration becomes a common phenomenon, and the pollution of the indoor air volatile organic compound caused by the decoration of the room is greatly increased. In addition, due to the need of thermal insulation of the building, the indoor ventilation is getting worse and the harmful gas pollution concentration is getting higher and higher, thus causing the problem of indoor pollution to become more and more serious. In the existing health standards, only the concentration limit of the single contaminant is present. When two or more pollutants are present at the same time, if the information about the joint action of the two or more pollutants is mastered, the health hazard can be more accurately evaluated. In this study, the indoor air pollution status of newly-decorated rooms in Nanjing area was investigated, and the general toxicology and cell toxicology experiments were carried out on the basis of the monitoring results, and the main volatile and harmful chemicals in the room air were studied. The combined action of the toxicity of the object is carried out, and the combination of the benzene and the formaldehyde-induced cell genetic toxicity is studied by using the molecular biology technology, and the combination action of the benzene and the formaldehyde-induced cell genetic toxicity can be studied by using the molecular biology technology, The monitoring results of the pollution condition show that the pollutants in the indoor air after the new decoration mainly include ammonia, formaldehyde, benzene, toluene, xylene and ethylbenzene, among which ammonia, formaldehyde, benzene, toluene, xylene are in excess of the standard, and the average concentration of ammonia, formaldehyde, benzene, toluene, xylene is in excess of the standard, and the average concentration of the 1h is over the standard. The numbers were 77. 78%, 93.2%, 52. 78%, 37. 50%, 26. 47% and 67. 5 times, 37. 9 times, respectively. The LC50 of the single or mixed chemical is measured by the static inhalation of the mouse, and the estimated value of the LC50 of the mixture is calculated according to the formula, according to the estimated value of the LC50 of the mixture. The results show that, under the condition of this experiment, benzene and formaldehyde, formaldehyde and ammonia, benzene, formaldehyde and ammonia, mixed benzene and formaldehyde are determined according to the actual proportion of the on-site monitoring results. The combined effect of the present invention is the phase. In vitro cell culture experiments, the effects of benzene or/ and formaldehyde on the growth of primary rat lung fibroblasts and CHL cells were first tested. Cell growth half inhibitory concentration (IC50), root according to the expected value of the IC50 and the ratio Q value of the measured value, the joint action mode is evaluated according to the Smyth method. When the cytotoxicity of the cells is greater than that of the benzene, the inhibitory concentration (IC50) of the half inhibitory concentration (IC50) of the two cells is not on the order of magnitude. When the benzene and the formaldehyde act together in the primary rat lung fibroblasts, if the dosage of the formaldehyde is much larger than that of the benzene (the proportion is 26: 8), the combined toxicity of the formaldehyde is shown as the phase. In addition, when formaldehyde and benzene are exposed at the same toxic dose, its combined toxicity is shown to be a synergistic effect. At the same time, benzene and formaldehyde are in equal toxicity. The combined effect of the dose on the in vitro culture of CHL cells also showed a synergistic effect. The effects of benzene and formaldehyde on the genetic toxicity of cultured cells in vitro and the possible mechanism of oxidative damage were studied by orthogonal experimental design. The results of the analysis of orthogonal experiment showed that the DNA-breaking and the cell apoptosis rate, the increase of DNA-crosslinking rate and the growth of MDA in the in vitro culture cells could be caused by the orthogonal experimental analysis of variance. In addition, the activity of SOD and the level of GSH decreased, and the degree of DNA damage was consistent with the trend of oxidative damage. Interacting (P0.05), from The results of the experimental results show that, within a certain dose range, the curve is away from the dose, and the interaction is synergistic. in this study, that volatile chemical of indoor air can be produce The combination of benzene and formaldehyde may produce a synergistic cytotoxic effect and a cellular genotoxic effect.
【学位授予单位】：东南大学
【学位级别】：硕士
【学位授予年份】：2004
【分类号】：X51

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