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1.
K. Norpoth W. Stücker E. Krewet G. Müller 《International archives of occupational and environmental health》1988,60(3):163-168
Summary From preliminary experiments it was known that radiolabelled benzene and some of its metabolites during its metabolic activation process produce different in vitro DNA-phenyladducts in mitoplasts [5, 11].As we reported previously [9] at least one of these adducts, N-7-phenylguanine, is excreted in the urine of rats in measurable amounts, probably through an excision-repair mechanism after an inhalation experiment. Now we found, after i.p. application of benzene in the urine of rats, a compound separated by cation-exchange chromatography that behaves like a synthezised N-7-phenylguanine reference substance with respect to its retention index and the UV-absorption. This finding could be confirmed by HPLC-measurements with reversed-phase carrier materials. Silylation and gaschromatographic/mass spectrometric (GC/MS) separation of the fraction, which contains the phenylguanine, revealed that these fractions contain further phenyl adducts. Furthermore we studied the time-dependent excretion of the DNA-base adduct. Surprisingly the excretion dropped to zero on the fourth day and showed a new increase thereafter. 相似文献
2.
佛山市城区室内装修污染特征初探 总被引:8,自引:0,他引:8
目的 为了解佛山市室内装修空气污染状况,通过对佛山市室内装修污染物进行调查,掌握室内装修污染的一些基本特征并提出控制措施。方法 根据卫生部《室内空气质量卫生规范》以及《室内空气污染物的检验方法》方案,调查采用了问卷调查和现场检测的方法。结果 佛山市室内装修空气污染物主要为甲醛,苯,总挥发性有机物(TVOC),超标率分别为86%,36%,23%。结论 目前佛山市城区室内装修污染物的特征为:有机污染较无机污染严重,室内甲醛污染严重,苯次之而氢污染相对较轻,室内空气苯污染车辆、居室高于办公室,甲醛污染居室,办公室高于车辆。 相似文献
3.
取因职业而接触乙烯类或苯类的孕妇静脉血和他们新生儿脐带血进行SCE和MN测定。发现接触乙烯类或苯类的母血SCE(8.55±0.84,9.44±1.12)均高于对照组(7.68±1.40),他们新生儿脐带血SCE(8.94±1.43,8.75±0.88)也高于对照组(6.71±1.27)。接触乙烯类和苯类的母血微核率(0.833‰,0.727‰),高于对照组(0.267‰),他们新生儿脐血微核率(0.75‰,0.818‰)也高于对照组(0.267‰)。我们还发现母亲孕期被动吸烟增强了这两类诱变剂对他们后代的遗传毒性。 相似文献
4.
强兆艳 《天津医科大学学报》2001,7(1):45-47
目的:了解苯作业场所空气中苯浓度,推测苯作业发展趋势,方法:采用和平区1993-1999年39家工业企业,220个苯作业点,660个空气样品中的苯浓度值,按不同作业工种分为油漆组,化工(原料)组,粘胶组及印刷组,通过成组设计的多个样本比较的秩和检验进行分析。结果:1997年内不同作业组空气中苯平均浓度差异有显著性(H=8.00000 P<0.05),印刷组苯平均浓度高于其它作业组,其余年度中差异无显著性(P>0.05),1993-1999年,印刷组苯作业场所的苯平均浓度差异无显著性(P>0.05),结论:和平区苯作业开始由较低浓度过渡到较高浓度,以油漆业为主过渡到以印刷业为主,并且,1997年印刷组苯平均浓度超过国家卫生标准,应引起重视。 相似文献
5.
Ruth A. Etzel David L. Ashley 《International archives of occupational and environmental health》1994,66(2):125-129
Between March and November of 1991, approximately 9000 workers from 43 different countries battled the burning oil wells in Kuwait. To document the exposure of persons in Kuwait during the oil well fires to volatile organic compounds (VOCs), we obtained samples of blood from 14 U.S. personnel in Kuwait City in May of 1991 (group I) and 40 American firefighters working in the oil fields in October of 1991 (group II). Concentrations of VOCs in group I and group II were compared with those of a random sample of 114 persons in the United States (reference group). The median concentrations of VOCs in group I were equal to or lower than those in the reference group. We found significant differences between the median concentrations of several VOCs in group 11 and the reference group. Median levels of ethylbenzene were about 10 times higher among group II than among the reference group (0.53 g/I vs 0.052 g/l). Median levels of benzene, m-/p-xylene, o-xylene, styrene, and toluene among group II were more than double those of the reference group. Although firefighters had higher median concentrations of VOCs than the reference group, those American personnel in Kuwait not involved in fighting the oil fires had concentrations of VOCs comparable to those in the reference group. Blood VOC measurements indicate a significant increase in exposure to VOCs in firefighters, but do not demonstrate this in personnel in Kuwait City. 相似文献
6.
苯及其代谢产物在小鼠骨髓中形成DNA加合物的实验研究 总被引:3,自引:0,他引:3
目的 观察苯及其主要代谢产物苯酚、氢醌、苯醌及苯酚和氢醌联合染毒在小鼠骨髓中形成的 D N A 加合物及其髓性毒性。方法 改进的32 P 后标记方法。结果 苯及其主要代谢产物均能在小鼠骨髓细胞中形成至少1 种 D N A 加合物,相对加合物水平从0 .85 ×10 - 8 ~6 .78 ×10 - 8 不等。骨髓细胞计数结果表明:单独染苯酚或氢醌,对小鼠骨髓细胞均没有抑制作用,但二者联合染毒对小鼠却表现出增强的髓性毒作用。结论 苯及其主要代谢产物均能在小鼠骨髓细胞中形成 D N A 加合物,苯的代谢产物形成的 D N A 加合物与髓性毒性有关。 相似文献
7.
Summary A group of printing workers (n = 34) exposed to toluene was examined according to the concentrations of hippuric acid, phenol, o-cresol, and (m+p)-cresol in urine. The average concentration in the air of the workroom was 23 ppm. It is shown that, besides hippuric acid, small amounts
of o-cresol. which is not a normal constituent of urine, were formed from toluene. The occurrence of o-cresol could be proved by mass spectrometry. On account of the small amounts of benzene present in industrially used toluene—in this case 0.025%—the average concentration of phenol in urine of the exposed group was significantly higher statistically
than in urine from the controls
. 相似文献
8.
I. Gut 《Archives of toxicology》1976,35(3):195-206
Phenobarbital pretreatment (50 mg/kg/day for 3 days orally) of male Wistar rats increased V
max of benzene in vitro hepatic microsomal biotransformation about 6-fold without changing K
m
. However, benzene blood levels after oral, intraperitoneal, or subcutaneous benzene administration (3–3.5 mmoles/kg) were not influenced by phenobarbital pretreatment. The phenol blood levels after oral or intraperitoneal benzene were increased by phenobarbital pretreatment, but less than expected from in vitro data and only 3 h after benzene administration. Phenol elimination in urine after subcutaneous benzene was not affected by phenobarbital. After oral or intraperitoneal benzene administration, phenol urine excretion closely followed the levels of phenol in blood, i.e., rate of phenol urine excretion was significantly, but shortly increased, and the cumulative urine excretion of phenol increased very little or remained unchanged. Differences between the in vitro and in vivo observations of the effect of phenolbarbital on benzene biotransformation may partly be explained by distribution of benzene, which apparently limited benzene availability for biotransformation (V
d
=5.5) and caused rapid decrease of benzene concentrations in blood. Conditions for enzyme activity may have been substantially different in vitro vs. in vivo: in vitro concentrations of benzene were at least by an order of magnitude higher than phenol concentrations, while in vivo, an opposite relation prevailed making a competition for microsomal monooxygenase possible. Cofactor availability may be another rate-limiting step or factor of in vivo benzene biotransformation, as benzene ring hydroxylation requires high energy. The rate of in vitro hepatic microsomal benzene biotransformation proved to be of limited value when predicting benzene quantitative biotransformation in vivo in contradistinction to various substrates where the in vitro and in vivo biotransformation data are in good agreement 相似文献
9.
西安市饮用水中六六六滴滴涕污染的调查研究 总被引:6,自引:1,他引:6
为研究有机氯农药对西安市饮用水的污染状况,用气相色谱法测定了西安市21个点自备井水中六六六,滴滴涕的含量。结果表明,21个采样点饮用水中六六六的检出率为100%,滴滴涕的检出率为14.3%,结果提示六六六,滴滴涕的化学性质稳定及残留性所引起的远期危害不容忽视。 相似文献
10.
慢性苯中毒患者肿瘤坏死因子α基因多态性的研究 总被引:3,自引:0,他引:3
目的探讨肿瘤坏死因子α(TNFα)238及TNFα308基因的多态性与慢性苯中毒易感性的关系。方法以50例慢性苯中毒工人为病例组,60例接触苯而未中毒的工人为对照组,用巢式聚合酶链反应-限制性片段长度多态性(PCRRLFP)方法检测TNFα238及TNFα308基因的多态性,用病例-对照的研究方法对苯中毒的易感因素进行单因素和多因素分析。结果苯接触健康组TNFα238GG基因型为95%、AG基因型为5%、AA基因型为0%;苯中毒组TNFα238GG基因型为92%、AG基因型为6%、AA基因型为2%,两组差异无统计学意义(P>0.05)。苯中毒组TNFα308GG基因型为76%、AG基因型为24%、AA基因型为0%;苯接触健康组TNFα308GG基因型为93%、AG基因型为7%、AA基因型为0%。经χ2检验,苯中毒组TNFα308AG比率明显高于对照组,差异有统计学意义(χ2=6.22,P=0.013)。多因素分析结果表明,TNFα308AG基因型是苯中毒发生的独立危险因素(OR=5.3,P<0.05)。结论TNFα308AG基因型的个体容易发生苯中毒。 相似文献