甲苯接触者呼出气中甲苯动力学研究

对１４名职业性接触者及１８名志原受试者接触甲苯进行研究。班中呼出气中甲苯浓度波动很大。班后甲苯浓度的下降趋势符合两室动力学模型，其中快相半减期为４～５分钟，慢相半减期为２～２．５小时。引入统计矩分析与传统的室模型进行比较。因其计算方便且结果易于解释，矩分析法在动力学研究中具有潜在的意义。甲苯接触者体内平均滞留时间为１６２－２２５分钟，直观地反映出甲苯在体内的排泄。为了建立特定接触浓度的动力学方程式，我们用直线回归法估计Ｙ轴截距（Ａ、Ｂ值）。甲苯空气浓度与Ａ、Ｂ值密切相关（ｒ＝０．４３～０．９２，Ｐ＜０．０５）。从动力学方程中，推算出接触空气甲苯浓度１００ｍｇ／ｍ３（ＴＷＡ－８ｈ），脱离接触０、３０和１８０分钟以及次日晨，呼出气中甲苯职业生物接触限值分别为７０、２０、１０及０．３６ｍｇ／ｍ３。     

甲苯对印刷工人神经内分泌的影响

为探讨长期接触低浓度甲苯对神经内分泌系统的影响,作者对两所印刷厂的47名工人,(年龄23～62岁,平均44.4岁)进行了研究。其中 A 厂28人,接触甲苯工龄4～33年,平均18.4年;工作区空气中甲苯浓度3.3～356.4 mg/m~3,平均36.3 mg/m~3。B 厂19人,接触甲苯工龄3～39年,平均14.5年;工作区甲苯浓度19.8～468.6 mg/m~3,平均155.1 mg/m~3。接触     

接触甲苯工人的自然流产危险度

为探讨妇女在工作中接触甲苯对自然流产的影响,选择86名在扬声器制造厂工作至少妊娠1次以上的女工为研究对象,其中55人在装配车间工作,车间空气中的甲苯浓度为205～616mg/m~3,均值为317mg/m~3(高接触组);其余31人在其它车间工作,空气中甲苯浓度为0～103mg/m~3(低接触组)。另选190名到妇女保健所作产前检查或产后护理无甲苯     

某公司新建甲苯回收项目中苯和甲苯及二甲苯的监测

目的 分析甲苯回收项目存在的职业病危害因素及危害程度,为职业病危害控制提供依据.方法 按照GBZ 159-2004《工作场所空气有害物质的采样规范》,采用定点短时间方法采样.噪声测定依据GBZ/T 189.8-2007《工作场所物理因素测量噪声》规定按工人巡检路线确定噪声测定点,每处工作场所选3个测点取平均值记录,并根据工人停留时间计算8h等效连续A声级.结果 甲苯回收操作工接触的苯、甲苯、二甲苯的时间加权平均浓度(TWA)分别为2.9 mg/m3、13.2 mg/m3、＜3.3 mg/m3,甲苯工房苯、甲苯、二甲苯的短时间接触浓度(STEL)最大值为7.8 mg/m3、26.4 mg/m3,＜3.3mg/m3,氯化钙配制锅旁的盐酸监测浓度最大值为1.2 mg/m3,各岗位工人接触噪声8h等效声级为60.3～83.1 dB(A).结论 某化工有限公司新建甲苯回收项目正常生产过程中苯、甲苯、二甲苯和盐酸的浓度及噪声强度监测结果符合国家标准GBZ 2.1-2007及GBZ 2.2-2007.     

接触甲苯对女工月经的影响

为探讨妇女在工作中接触甲苯对月经的影响,作者进行了本次研究。高浓度接触组为231例在听力计和扬声器工厂工作的女工,平均年龄25.6±5.5岁,工龄6.0±4.0年,工作中使用甲苯作溶剂,车间空气中的甲苯浓度平均为361.4mg/m~3。选该厂其它车间的58例女工为低浓度接触组,车间空气中的甲苯浓度为0～102.7mg/m~3。另外选取187例无甲苯接触史在妇幼保健中心作产前检查或产后护理的妇女为厂外对照组,3组的平均年龄及其它人口统计学特征近似。按照调查表了解受试者的职业史、婚姻生育史、吸烟饮酒史以及月经周期、月经量、持续时间和痛经等方面的详细情况,结果经统计学处理。     

呼出气中甲苯的气相色谱测定法研究

呼出气中甲苯经用Tenax GC制成的吸附管富集后,再用871型热解吸仪在250℃下解吸,经10%FFAP/6201(60～80目)色谱柱分离,FID检测器检测。当样品体积为100ml时,最低检出浓度为0.001mg/m~3。标准曲线的相关系数为r=0.9999,实验室和现场样品的平均回收率分别为86.8%和99.71%。实验室样品平均相对偏差为4.89%。样品较稳定,在室温下密封保存一周无明显损失。呼出气甲苯和空气中甲苯浓度的相关系数r=0.7990。     

甲苯作业工人呼出气监测分析

为了探讨甲苯作业工人呼出气监测指标与作业环境甲苯暴露水平的相关性。同步采集16名作业工人呼出气及其作业环境空气样品各90份,检测甲苯含量,进行工人作业环境甲苯的暴露水平与生物样品呼出气甲苯含量的相关分析。结果显示,工人作业环境中甲苯的几何平均浓度为189.4 mg/m3(范围31~925 mg/m3),终末呼出气中甲苯的浓度随环境浓度的改变而变化。经相关分析,呼出气与空气中甲苯浓度呈显著正相关关系(r=0.98,P<0.01)。提示,甲苯作业工人的呼出气监测简便、易行,对挥发性有机溶剂的接触-反应关系的研究具有重要意义。     

苯接触者肺泡气毒物动力学研究

对接触不同浓度苯的工人70名(男45,女25)与志愿者9名(男) (?)续观察其工作接触后肺泡气中苯浓度的变化,分析苯经呼气排出规律。经毒物动力学校型分析,三室模(?)拟合良好,半衰期分别为1.24min,21.17min及2.5h。苯经呼气排出的速率男女工间无明显差异,随接触浓度高低变化甚小:志愿者吸入苯的排出较快。接触浓度为30mg/m~3时的呼气苯排出的动力学方程为Ct=11.45e~(-0.558t) 1.058×e~(-0.03271) 4.95e~(-0.00466(?));并提出肺泡气苯浓度的生物接触指数建议值:班末:17.46mg/m~3,班后30min:4.70mg/m~3。     

甲苯作业工人生物接触指标的研究

目的为职业性甲苯接触提供灵敏、特异的早期观察指标，为制订职业性甲苯接触的生物接触限值提供科学依据。方法空气样、血样和呼出气中甲苯测定采用气相色谱分析，尿中马尿酸含量测定采用苯磺酰氯比色法。结果呼出气和血中甲苯含量与环境中甲苯浓度间有明显的剂量-效应关系。结论呼出气和血中甲苯含量可作为诊断甲苯中毒可靠的生物监测指标。     

尿中甲苯的顶空气相色谱分析

目的：通过测定尿中甲苯浓度，探讨尿中甲苯作为接触甲苯的生物监测指标的意义。方法：用硫酸铵为释放剂，以氢火焰离子化检测器进行检测，对尿中甲苯进行顶空气相色谱法测定。同时，用活性炭膜吸附、气相色谱法测定空气中的甲苯，进行相关分析。结果：接触甲苯后尿中与车间空气中甲苯浓度相关系数r=0．813。本实验最低检出浓度为0．05mg／L，变异系数分别为1．7％～2．5％，回收率分别为96．0％～98．9％。结论：本方法灵敏度高、准确度好，操作简单、快速。尿中甲苯浓度与空气中甲苯浓度高度相关。     

接触叠氮酸作业工人的健康危害研究

对31名起爆药三硝基间苯二酚与叠氮化铅共沉淀结晶(D.S共晶)作业工人进行了临床检查;测定了生产场所HN_3浓度,多数低于0.5mg/m~2,少数高于10mg/m~3。工人工作2～18年,头痛、多梦、眼和咽刺激及血压降低明显多于对照组,但未见其器官性损害。工人短时间接触高浓度HN_3(12.8mg/m~3)有自觉不适,脱离接触后迅速消失。结合亚慢性HN_3吸入毒性,提出HN_3和NaN_3最高容许浓度各为0.2mg/m~3和0.3mg/m~3。     

Toluene in alveolar air during controlled exposure to constant and to varying concentrations

The concentration of toluene in the alveolar air was measured in 20 males and 17 females exposed for 7 h either to a constant exposure to 100 ppm toluene or to a varying exposure with the same time-weighted average, but with peaks of 300 ppm every 30 min. Both exposure schedules included 50 to 100 W exercise in three 15-min periods. Repetitive measurements of the toluene concentrations in the alveolar air were made in two 30-min periods, one at rest and one including work. At rest the alveolar concentration increased rapidly in response to an increase in the inspiratory air concentration, while exercise delayed this increase by about 2 min, probably due to an altered distribution of toluene in the body. The average alveolar concentration was 16.5 +/- 6.8 ppm (mean +/- SD) at rest and 19.5 +/- 5.3 ppm in the period including exercise while there was no difference between constant and varying exposure. The alveolar toluene concentration tended to be higher in females than in males both at rest and during exercise. Subjects exercising with an intensity of 100 W had 25% higher values at rest than those exercising at 75 W. The excretion of the metabolites hippuric acid and orthocresol in the last 3 h of exposure was correlated to the alveolar toluene concentration at rest but not during work. Besides this, body height and weight influenced the excretion rates, still leaving a large unexplained interindividual variation.     

Toluene in alveolar air during controlled exposure to constant and to varying concentrations

Summary The concentratiuon of toluene in the alveolar air was measured in 20 males and 17 females exposed for 7 h either to a constant exposure to 100 ppm toluene or to a varying exposure with the same time-weighted average, but with peaks of 300 ppm every 30 min. Both exposure schedules included 50 to 100 W exercise in three 15-min periods. Repetitive measurements of the toluene concentrations in the alveolar air were made in two 30-min periods, one at rest and one including work. At rest the alveolar concentration increased rapidly in response to an increase in the inspiratory air concentration, while exercise delayed this increase by about 2 min, probably due to an altered distribution of toluene in the body. The average alveolar concentration was 16.5 ± 6.8 ppm (mean ±SD) at rest and 19.5 ± 5.3 ppm in the period including exercise while there was no difference between constant and varying exposure. The alveolar toluene concentration tended to be higher in females than in males both at rest and during exercise. Subjects exercising with an intensity of 100 W had 25% higher values at rest than those exercising at 75 W. The excretion of the metabolites hippuric acid and orthocresol in the last 3 h of exposure was correlated to the alveolar toluene concentration at rest but not during work. Besides this, body height and weight influenced the excretion rates, still leaving a large unexplained interindividual variation.     

Toluene metabolism during exposure to varying concentrations combined with exercise

Summary The urinary excretion of hippuric acid (HA) and ortho-cresol (O-cr) in man was measured in two studies of 7-h exposure to toluene in a climate chamber, either constant concentration of 100 ppm or varying concentrations containing peaks of 300 ppm but with a time-weighted average of 100 ppm. In Study A, four males were exposed to clean air and to constant and varying concentrations of toluene in combination with rest and with 100 W exercise in 140 min. Exercise increased end exposure excretion rate of HA and O-cr by 47 and 114%, respectively. After exposure, all excess HA was excreted within 4 h, while O-cr was eliminated with a half life of about 3 h. Alveolar air concentration of toluene varied between 21 and 31 ppm during constant exposure and between 13 and 57 ppm during varying exposure, but no difference in mean alveolar toluene concentration or in metabolite excretion was seen between the exposure schedules. In Study B, 32 males and 39 females aged between 31 and 50 years were exposed once to either clean air, constant or varying concentrations of toluene. Background excretion rate of HA was 0.97 ± 0.75 mg/min (1.25 ± 1.05 g/g creatinine) and rose to 3.74 ± 1.40 mg/min (3.90 ± 1.85 g/g cr) during the last 3 h of exposure to 100 ppm toluene. The corresponding figures for O-cr were 0.05 ± 0.05 g/min (0.08 ± 0.14 mg/g cr), and 2.04 ± 0.84 g/min (2.05 ± 1.18 mg/g cr). The individual creatinine excretion rate was considerably influenced by sex, body weight and smoking habits, thus influencing the metabolite concentration standardised in relation to creatinine. It is concluded that both metabolites are estimates of toluene exposure. O-cr is more specific than HA, but the individual variation in excretion of both metabolites is large, and when implementing either of them as biological exposure indices, the influence of sex, body size, age as well as consumption of tobacco and alcohol has to be considered.     

Exposure to methylene chloride. I Its concentration in alveolar air and blood during rest and exercise and its metabolism.

Fourteen subjects were exposed to about 870 and 1,740 mg/m3 of methylene chloride in the air during rest and physical exercise on a bicycle ergometer. The duration of each exposure period was 30 min. Each subject was exposed during four periods. The concentration of methylene chloride in the alveolar air increased in the beginning but had a tendency to level off at the end of each period. There was a high correlation between the alveolar and arterial concentration of methylene chloride. The uptake of methylene chloride was about 55 % of the supplied amount at rest, about 40% at a work load of 50 W, and about 30 and 35 % at 100 and 150 W, respectively. The concentration of carboxyhemoglobin (COHb) increased both during and after exposure. With exposure to 1,740 mg/m3 a concentration of COHb in the blood of about 0.85 g/100 ml was reached. This value corresponds to about 5.5 % COHb.     

Exposure to acetone. Uptake and elimination in man

Eight male subjects were exposed to acetone vapor on two occasions for 2 h in the laboratory. On the first occasion they were exposed to about 1,300 mg/m3 during rest and on the second occasion to about 700 mg/m3 during rest (30 min) and exercise at different work loads on a bicycle ergometer (90 min). The total uptake of acetone was 0.6--1.2 g, and the relative uptake was about 45%. The concentration of acetone in alveolar air was 30--40% of that in the inspiratory air, and it was not affected by exposure time or work load. The concentration of acetone in blood increased continuously with increased uptake during exposure, and there was no tendency towards equilibrium. The half-time of acetone in alveolar air as about 4 h, and in venous and arterial blood it was about 6 and 4 h, respectively. The highest concentrations of acetone in urine were measured 3--3.5 h after exposure. The elimination of acetone via the lungs corresponded to about 20% of the total uptake. Only about 1% of the uptake was excreted via urine.     

职业接触甲醛对工人神经行为功能的影响

[目的]评价职业接触甲醛对暴露工人精神情绪和神经行为功能的影响。[方法]调查分析昆山市存在甲醛职业危害企业18家,采用WHO推荐的神经行为功能测试组合,对65名甲醛接触工人和70名对照组工人进行神经行为功能测试。[结果]18家企业甲醛平均浓度为0.43mg,mg/m~3,最高达3.11 mg/m~3,超标暴露点达29.1%。暴露组工人数字跨度、视觉保留、正确打点数和二次打点总和低于对照组,差异有统计学意义(P<0.05);紧张一焦虑、抑郁一沮丧升高,有力一好动项降低,与对照组比较差异有统计学意义(P<0.05)。[结论]长期职业性接触甲醛可导致工人明显精神情绪和神经行为改变,为暴露工人的早期损害提供了两个有意义的标志。     

Two cases of acute toluene intoxication

Two patients exposed to high concentrations of toluene in air (greater than 7000 mg/m3) were found at the bottom of a small swimming pool under construction. Their symptoms were stupefaction, paresis, and amnesia. Patient A had been exposed for three hours and patient B for two hours. Ninety minutes after the exposure, the toluene blood concentration in patient A was 4.1 mg/l and in patient B 2.2 mg/l. Urinary ortho-cresol secretion was shown to be a good index of exposure to toluene. After high level exposure, urinary meta-cresol excretion may also be used to monitor toluene exposure.     

Two cases of acute toluene intoxication.

Two patients exposed to high concentrations of toluene in air (greater than 7000 mg/m3) were found at the bottom of a small swimming pool under construction. Their symptoms were stupefaction, paresis, and amnesia. Patient A had been exposed for three hours and patient B for two hours. Ninety minutes after the exposure, the toluene blood concentration in patient A was 4.1 mg/l and in patient B 2.2 mg/l. Urinary ortho-cresol secretion was shown to be a good index of exposure to toluene. After high level exposure, urinary meta-cresol excretion may also be used to monitor toluene exposure.