柴油机排出颗粒物不同组分对哺乳动物遗传毒性的研究

采用大鼠原代肝细胞ＵＤＳ试验，对国产东风柴油机排出颗粒物不同分离组分进行研究，评价各组分对ＤＮＡ的损伤作用。结果表明：各种不同组分（有机酸Ｆ１组分除外）均可诱导ＤＮＡ的损伤，导致ｃｐｍ值的升高，且在一定范围内存在剂量－反应关系，其中以有机碱Ｆ２和多环芳烃Ｆ４组分的毒性较高。     

汽油车排出颗粒物的化学组分分析

目的 为了进一步了解汽油车尾气颗粒物的化学成分。方法 运用高效液相色谱法测定了尾气颗粒物有机提取物中6种多环芳烃含量,运用原子吸收分光光度法测定了尾气颗粒物无机提取物中5种重金属含量。结果 有提取物中6种多环芳烃按含量高低依次为：苯并（a)芘＞菲＞晕苯＞苯并（a)蒽＞Qu＋芘,其中苯并（a)芘含量占40％。无机提取物中5种重金属按含量高低依次为：铅＞镍＞铬＞镉＞锰,其中铅含量占37％。结论 汽油车尾气颗粒物含量较多的组分是苯并（a）芘和铅。     

柴油机排出颗粒物不同分离组分对SHE细胞恶性转化作用的研究

应用ＳＨＥ细胞对柴油机排出颗粒物不分离组分进行细胞毒性的转化试验，结果表明，各种组分具有明显的诱导ＳＨＥ细胞恶性转化的能力，并在一定范围内存在剂量－反应关系，不同分离组分其细胞毒辣性有所差别。     

不同粒径柴油机排出颗粒物的体外微核实验研究

用ＤＦＪ－１五码分级器对国产中型４９５Ａ－３３型柴油机颗粒物进行分级采样并对各不同粒径的柴油机颗粒物的提取物进行体外培养细胞微核实验。结果发现各粒径的颗粒物中以粒径＜１．１μｍ的颗粒物最多，占总颗粒物重量的４５．２％。且此部分颗粒提取物致体外细胞微核形成的能力最强，并随着颗粒粒径的增大微核出现率逐渐降低。这提示控制柴油机排出颗粒物的污染既要减少颗粒物质排出的总量，更要注重对小粒径颗粒物的过滤以有效降低柴油机排出颗粒物的毒性。     

柴油机排出颗粒物有机组份对培养CHO细胞微核率的影响

柴油机排出颗粒物有机组份对培养ＣＨＯ细胞微核率的影响上海医科大学公共卫生学院（上海２０００３２）吕源明，叶舜华近年来，国内外对柴油机排出颗粒物的生物学效应方面的研究较多、人们对其危害性也有了越来越多的认识。柴油机排出颗粒物的数量是汽油机的２０～１００...     

不同粒径柴油机排出颗粒物的致突变性研究

用ＤＦＪ－１五码分级器对国产中型４９５Ａ－３３型柴油机颗粒进行分级采样，对各不同粒径的颗粒物的提取物进行Ａｍｅｓ试验，结果发现各粒径的颗粒物中以粒径〈１．１μｍ的颗粒物最多，占总颗物重量的４５．２％，且此部分颗粒提取物的致突变性最强，并随着颗粒粒径的增大期致突变性逐渐减小。     

柴油机排出颗粒提取物对SHE细胞恶性转化的研究

采用ＳＨＥ细胞恶性转化实验对５种不同型号的柴油机颗粒提取物的致突变性及潜在致癌性进行研究。结果表明，所选５种型号柴油机颗粒提取物均存在细胞转化作用，并存在轻型车高于中、重型车的趋势。     

助动车排出颗粒物遗传毒性研究

采用鼠伤寒沙门氏菌Ames试验和V_(79)细胞微核试验,对国产及进口有代表性的5种牌号助动车尾气排出颗粒物进行分析,为制订相应的卫生标准提供依据。 样品来源:选用永久(912型)、火鸟、飞利浦、霸伏(意大利)、汤姆斯(美国)5种国产及进口车型,使用年限、运行里程及保养情况基本一致。采用大流量空气采样器(1m~3/min),分别在助动车怠速及加速情况下抽     

柴油机排出颗粒提取物对细胞间隙通讯的影响

利用划痕染料示踪技术（ＳＬＤＴ）将荧光染料引入细胞内，观察细胞间荧光染料的扩散以判断经缝隙连结的细胞间通讯的方法，分析了柴油机排出颗粒物（ＤＥＰ）的提取物对细胞间通讯的影响。结果表明：ＤＥＰ提取物能够明显抑制Ｂａｌｂ／ｃ３Ｔ３细胞间隙通讯，提示ＤＥＰ对细胞间隙通讯的影响可能是其致细胞恶变的原因之一。     

柴油车尾气颗粒物提取物对V79细胞的毒性

目的 观察柴油车尾气颗粒物提取物(DEPE)对中国仓鼠肺成纤维细胞(V79)增殖、细胞膜完整性及氧化损伤的毒性。方法 DEPE染毒不同浓度或时间后，通过检测V79细胞的细胞生存率、乳酸脱氢酶(LDH)漏出率、谷胱甘肽(GSH)含量、谷胱甘肽过氧化物酶(GSH-PX)活力的变化规律及相互的关系，评价DEPE对细胞的一般毒性和氧化损伤作用。结果 在该实验条件下，DEPE可致细胞生存率降低，半数抑制浓度(IC50)约为6400μ/ml；细胞内LDH漏出率增加，GSH含量下降，并伴随着GSH—Px活力升高。结论 一定剂量下，DEPE可降低细胞生存率，损伤细胞膜，致细胞氧化损伤。     

冬季大气中不同粒径颗粒物浓度及5种重金属成份的分析

运用ＤＦＪ－１型五段分级器和ＣＹＱ－０６型大流量采样器，采集冬季太原市一采样点大气悬浮颗粒物，分析颗粒物的浓度与不同粒径颗粒物的比重，并对颗粒物用索氏酸提取法和模拟肺泡液溶出法处理后，测定其中Ｐｂ、Ｍｎ、Ｃｒ、Ｎｉ、Ｃｄ５种重金属元素的含量。结果表明：采样点地区冬季大气颗粒物污染严重，特别是小粒径颗粒物的污染，而且其中所含有毒重金属元素可随颗粒物进入人体并部分溶出，其潜在危害值得进一步研究。     

Diesel exhaust exposures in port workers

Exposure to diesel engine exhaust has been linked to increased cancer risk and cardiopulmonary diseases. Diesel exhaust is a complex mixture of chemical substances, including a particulate fraction mainly composed of ultrafine particles, resulting from the incomplete combustion of fuel. Diesel trucks are known to be an important source of diesel-related air pollution, and areas with heavy truck traffic are associated with higher air pollution levels and increased public health problems.

Several indicators have been proposed as surrogates for estimating exposures to diesel exhaust but very few studies have focused specifically on monitoring the ultrafine fraction through the measurement of particle number concentrations. The aim of this study is to assess occupational exposures of gate controllers at the port of Montreal, Canada, to diesel engine emissions from container trucks by measuring several surrogates through a multimetric approach which includes the assessment of both mass and number concentrations and the use of direct reading devices. A 10-day measurement campaign was carried out at two terminal checkpoints at the port of Montreal. Respirable elemental and organic carbon, PM₁, PM_2.5, PM_resp (PM₄), PM₁₀, PM_tot (inhalable fraction), particle number concentrations, particle size distributions, and gas concentrations (NO₂, NO, CO) were monitored.

Gate controllers were exposed to concentrations of contaminants associated with diesel engine exhaust (elemental carbon GM = 1.6 µg/m³; GSD = 1.6) well below recommended occupational exposure limits. Average daily particle number concentrations ranged from 16,544–67,314 particles/cm³ (GM = 32,710 particles/cm³; GSD = 1.6). Significant Pearson correlation coefficients were found between daily elemental carbon, PM fractions and particle number concentrations, as well as between total carbon, PM fractions and particle number concentrations. Significant correlation coefficients were found between particle number concentrations and the number of trucks and wind speed (R² = 0.432; p < 0.01). The presence of trucks with cooling systems and older trucks with older exhaust systems was associated with peak concentrations on the direct reading instruments. The results highlight the relevance of direct reading instruments in helping to identify sources of exposure and suggest that monitoring particle number concentrations improves understanding of workers' exposures to diesel exhaust.

This study, by quantifying workers' exposure levels through a multimetric approach, contributes to the further understanding of occupational exposures to diesel engine exhaust.     

汽油和柴油机动车排出颗粒物表面特征观察

采用扫描电镜加Ｘ射线能谱分析技术，对太原市汽油和柴油机动车排出颗粒物的表面成分和形态特征进行观察，结果显示：汽油车排放的颗粒物其表面含Ｐｂ量高，平均含２２．５％，而柴油车平均含Ｐｂ量低，仅含８％；但柴油车颗粒物的颗粒明显小于汽油车，≤２μｍ颗粒物前者占７３％，后者占６２％。颗粒物形状不规则，表面粗糙呈多孔状，二类汽车排放颗粒物形状相似。     

电焊工作场所超细颗粒与细颗粒暴露特征研究

目的研究电焊工作场所超细颗粒、细颗粒暴露特征。方法检测某电焊工作场所超细、细颗粒的质量浓度及其分布、数量浓度、形态学和化学元素含量,记录检测点距离、生产活动及风速等影响因素。结果超细、细颗粒的浓度与电焊作业点数量和生产活动密切相关,距离作业点3.1 m处颗粒数量浓度和质量浓度明显低于距离作业点1.1 m处(P0.05),高窗口风速的检测点颗粒数量浓度明显低于低窗口风速的检测点(P0.01),车间内焊接作业前与车间外大气化学元素含量较接近,但车间内焊接作业前超细、细颗粒浓度明显高于车间外大气(P0.01)。结论电焊作业超细、细颗粒浓度与工人作息时间、作业点数量、检测距离、窗口风速、背景值密切相关。     

沙尘暴细颗粒物的化学成分及其毒理学研究

沙尘暴已成为影响人类健康的主要危害因素之一,沙尘暴细颗粒物包括水溶性离子、有机物及不溶性物质,目前其对人体健康的影响引起人们的关注。流行病学研究表明,沙尘暴细颗粒物不仅可以引起呼吸系统疾病,对心血管、神经、免疫系统都会产生影响;毒理学研究也表明,沙尘暴细颗粒物对人和动物多种组织器官均有毒性作用,通过产生各种自由基引起器官组织发生氧化损伤和遗传损伤可能是沙尘暴细颗粒物毒作用的主要机制。     

Diesel engine exhaust exposure in underground mines: Comparison between different surrogates of particulate exposure

Exposure to diesel particulate matter (DPM) is frequently assessed by measuring indicators of carbon speciation, but these measurements may be affected by organic carbon (OC) interference. Furthermore, there are still questions regarding the reliability of direct-reading instruments (DRI) for measuring DPM, since these instruments are not specific and may be interfered by other aerosol sources. This study aimed to assess DPM exposure in 2 underground mines by filter-based methods and DRI and to assess the relationship between the measures of elemental carbon (EC) and the DRI to verify the association of these instruments to DPM. Filter-based methods of respirable combustible dust (RCD), EC, and total carbon (TC) were used to measure levels of personal and ambient DPM. For ambient measurements, DRI were used to monitor particle number concentration (PNC; PTrak), particle mass concentration (DustTrak DRX and DustTrak 8520), and the submicron fraction of EC (EC_1;Airtec). The association between ambient EC and the DRI was assessed by Spearman correlation. Geometric mean concentrations of RCD, respirable TC (TC_R) and respirable elemental EC (EC_R) were 170 µg/m³, 148 µg/m³, and 83 µg/m³ for personal samples, and 197 µg/m³, 151 µg/m³, and 100 µg/m³ for ambient samples. Personal measurements had higher TC_R:EC_R ratios compared to ambient samples (1.8 vs. 1.50) and weaker association between EC_R and TC_R. Among the DRI, the measures of EC₁ by the Airtec (ρ = 0.86; P < 0.001) and the respirable particles by the DustTrak 8520 (ρ = 0.74; P < 0.001) showed the strongest association with EC, while PNC showed a weak and non-significant association with EC. In conclusion, this study provided important information about the concentrations of DPM in underground mines by measuring several indicators using filter-based methods and DRI. Among the DRI, the Airtec proved to be a good tool for estimating EC concentrations and, although the DustTrak showed good association with EC, interferences from other aerosol sources should be considered when using this instrument to assess DPM.     

Diesel exhaust particles and allergenicity of pollen grains of Lilium martagon

Diesel exhaust particles are considered as the most important parts of air pollutants. Diesel exhaust particles have been shown to express both adjuvant activity for sensitization against common allergens and enhancing effects on allergic symptoms in sensitized individuals. In this research, pollen grains of Lilium martagon that are known as a non-allergic substance were collected and exposed to DEP 5 and 10 days. The allergy potency of different pollen extracts were compared by means of skin test, as well as analyses blood eosinophil numbers and IgE levels in the treated animals. Normal and DEP-exposed pollen grains were examined by scanning electron microscopy. Pollen extracts were also studied by SDS-PAGE for DEP-induced changes in protein profiles. Allergic bands were also studied and checked by using immunoblotting method. The results of the investigated allergy tests showed that DEP-exposed pollen grains are effective in inducing allergic symptoms. According to our microscopic observations, organic substances that exist in the DEP, mediate agglomeration of particles on the pollen surface. In appropriate conditions, water-soluble components of DEP may induce changes that affect the release of pollen proteins. SDS-PAGE showed protein profiles of pollen grains were changed and some new bands appeared in DEP-exposed pollen grains. Immunoblotting studies showed a new band in DEP-exposed pollen grains that react strongly with anti-IgE, but there is no allergenic band in normal pollen grains. On the other hand, diesel exhaust particles can carry pollen allergen molecules, induce new proteins (allergens), and also act as adjuvant for allergens.