工作场所空气中尿素粉尘测定

目的 建立工作场所空气中尿紊粉尘的检测方法.方法 工作场所空气中的尿素粉尘经测尘滤膜采集、水洗脱后,酸性条件下,尿素与对二甲氨基苯甲醛(PDAB)反应生成黄色化合物,在440 nm波长下比色测定.结果 方法在0～200.00 ms/L有良好线性关系,检出限为5.68 ms/L,空气中最低检出质量浓度为0.47 ms/m3(以采样体积300 L计算),精密度为1.04%～1.77%,洗脱效率为102.9%-115.2%.结论 该方法各项指标均符合WS/T 73-1996<工作场所空气中毒物检测方法的研究规范>要求,适用于工作场所空气中尿素粉尘的测定.     

作业场所空气中碳纤维粉尘卫生标准的研究

本文在广泛收集已有资料的基础上，进行了必要的现场调查和实验研究，经综合分析提出了碳纤维粉尘的卫生标准。实验研究结果证实，碳纤维及其复合材料粉尘的毒性和致纤维化作用轻。现场调查结果表明，碳纤维粉尘对皮肤和眼有刺激作用．但受检查者胸片无尘肺样改变，对肺功能也无明显影响。基于我国作业场所空气中有害物质卫生标准的研制经验，参比类同污染物的最高容许浓度数值，建议作业场所空气中碳纤维粉尘的最高容许浓度为6mg／m3，时间加权平均容许浓度为3mg／m3。根据已获资料，本建议标准可考虑适用于碳纤维复合材料粉尘。可行性研究表明，碳纤维生产和复合材料加工过程中的粉尘浓度不高，通过加强防尘措施，不难达到本建议标准的要求。     

The dangers to health of fine dust particles in the air

Many scientific studies have been published that connect all kinds of toxicological characteristics offine dust particles, measured in vitro, with lung damage parameters both in animals and humans. These studies do not provide an unequivocal picture on the mechanisms that are responsible for the perceived connection between exposure to fine dust and the degree of illness and death. Without connecting to specific sources of air pollution, this type of study moreover, is only of limited value for drawing up control policy. Even if one or more responsible properties could be determined, it is still unlikely that these would be translated into a standard for permitted levels of concentration in the open air. It is far more likely that such insight will be used for specific source policy aimed at tackling the sources that contribute the most to the harmfulness of the mixture of air pollution.     

Quantification of house dust mite allergens in ambient air

The house dust mites Dermatophagoides pteronyssinus and Dermatophagoides farinae are important sources of indoor allergens. In sensitized patients, house dust mites induce and exacerbate diseases like asthma bronchiale, rhinitis, and conjunctivitis. The most significant exposure of persons occurs overnight in bed and to a lesser extent, during the daytime while performing activities like vacuum cleaning or bed making. In general, house dust mite antigens are quantified in samples of reservoir dust of carpets or beds. Yet, assessing allergens in ambient air would better represent human exposures because inhalation is the main route of uptake, and a close correlation between levels of floor and air antigens has not yet been proved. Unfortunately, because of extremely low airborne particle concentrations, analyses are difficult to perform and depend on sophisticated sampling strategies, as well as on sensitive immunometric detection assays. Using monoclonal immunoassays, house dust mite antigens, quantified in undisturbed conditions in ambient air, are found at pg/m3 levels. The disturbance of reservoir dust by vacuum cleaning or bed making increases the airborne allergen levels up to ng/m3 concentrations. In this review, we discuss the current knowledge regarding the analysis of airborne house dust mites in both undisturbed and disturbed ambient air. The advantages and disadvantages of different sampling strategies are outlined.     

Efficiency of dust sampling inlets in calm air.

Measurement of airborne dust concentrations usually involves drawing a sample of the dust-laden air into the measuring instrument through an inlet. Even if the surrounding air is calm, theoretical calculations predict that large particles may not be sampled accurately due to the combined effects of gravity and inertia on the particles near the sampling inlet. Tests were conducted to determine the conditions of particle size, inlet radius, and flow rare necessary for accurate dust sampling. A coal-dust aerosol was sampled simultaneously through inlets of different diameters at the same volume flow-rate and collected on filters. The dust was removed from the filters and the particles were counted and sized with a Coulter counter. Results showed that published criteria for inlet conditions for correct sampling are overly restrictive and that respirable-size particles are sampled correctly in the normal range or operation of most dust sampling instruments.     

车间空气中硅藻土粉尘卫生标准的研究

通过硅藻土粉尘的动物致纤维化实验、家兔红细胞溶血实验研究，结果表明硅藻土粉尘的细胞毒性较低，致纤维化作用较弱。通过流行病学调查和现场劳动卫生学调查，利用目前较公认的寿命表法进行粉尘容许浓度的计算，在参考国内外有关资料和国外标准的基础上，提出含游离ＳｉＯ２１０％以下的硅藻土粉尘的卫生标准的建议值为１０ｍｇ／ｍ￣３。     

空调隔尘网尘螨过敏原的检测

目的 检测安徽省芜湖地区家庭空调隔尘网灰尘和空调开机前、后室内空气中粉尘螨Ⅰ类过敏原（Derf 1）和屋尘螨Ⅰ类过敏原（Der p 1）浓度,以探讨隔尘网中尘螨过敏原与哮喘发病的关系.方法 分别从哮喘患者和健康居民家庭采集空调隔尘网灰尘样本各30份,同时用粉尘采样器采集哮喘患者和健康居民室内空气粉尘样本,开机前、后各采集30份.ELISA法检测Derf1、Derp 1的浓度,Dot-ELISA检测灰尘提取液过敏原性.结果 健康人群（家庭）组隔尘网灰尘中的过敏原Derf1、Derp 1浓度中位数分别为1.49和1.28 μg/g;哮喘患者（家庭）组隔尘网灰尘中的过敏原Derf1、Derp 1浓度中位数分别为0.73和0.85 μg/g,二者差异有统计学意义（分别为P＜0.01,P＜0.05）.健康人群（家庭）组的空调开机前空气中Derf1、Derp 1浓度中位数分别为4.65和5.90 ng/m3,开机后分别为7.65和7.35 ng/m3.哮喘患者（家庭）组空调开机前空气中Derf1、Derp 1浓度中位数分别为5.05和5.90 ng/m3,开机后分别为7.15和7.10 ng/m3.检测结果显示,打开空调送风情况下,哮喘患者（家庭）组与健康人群（家庭）组的空气中Derf1、Der p 1浓度均比未开空调时高,且差异有统计学意义（P＜0.05）.Dot-ELISA分析显示,灰尘提取液中过敏原能与螨过敏性哮喘患者的IgE产生结合反应.结论 芜湖地区居民空调隔尘网中含有尘螨Ⅰ类过敏原,空调开启送风后空气中尘螨的2个主要过敏原浓度均显著升高,应重视家用空调的清洁与净化,定期清洗、更换隔尘网以防止或减少尘螨孳生.     

作业场所空气中粉尘浓度不同测定方法的比较

目的 探讨2种不同原理不同的采样器测定地质勘探作业呼吸性粉尘浓度差异性,并对呼吸性粉尘接触浓度和环境浓度之间的关系进行了研究。方法 2种采样器分别为撞击式和向心式;呼吸性粉尘接触浓度测定采用个体采样器,由工人佩戴进行连续采样,环境浓度采样是按国标进行固定点短时采样。结果 2种不同采样器测定结果在某些工种中存在组间差异,且撞击式所 结果高;呼吸性粉尘接触浓度与环境浓度比较,虽未发现组间差异,但后者测定结果稳定性较差（CV＝2．38,前者仅为0．75）。结论 向心式采样结果更好、呼吸性粉尘接触浓度客观、稳定,将它作为经常性劳动卫生监督和粉尘危害评价指标更理想。     

Analysis of quartz by FT-IR in air samples of construction dust

The construction industry is reported to have some of the highest exposures to silica-containing dust. With the designation of crystalline silica as a group I human carcinogen by the International Agency for Research on Cancer (IARC), there exists a need for an analytical method to accurately quantify low levels of quartz. A method is described that uses FT-IR for quartz analysis of personal air samples collected from heavy and highway construction sites using 4-stage personal impactors. Sample filters were ashed and 13-mm or 5-mm pellets were prepared. Absorbance spectra were collected using FT-IR at resolution of 1 cm(-1) and 64 scans per spectrum. Two spectra were collected per sample using the appropriate background spectrum subtraction. Spectral manipulations such as Fourier self-deconvolution and derivatizations were performed to improve quantification. Peak height for quartz was measured at 798 cm(-1) for quantitative analysis. The estimated limit of detection for the 5-mm pellets was 1.3 microg. Recoveries of Min-U-Sil 5 spikes showed an average of > or = 94 percent for the two pellet types. The coefficient of variation of the 5-mm pellet was 9 percent at 6 microg quartz load, and 7 percent at 62 microg load. Interferences from clay, amorphous silica, concrete, calcite, and kaolinite were investigated, these being the more likely sources of interferences in construction environment. Spikes of mixtures of amorphous silica or kaolinite with Min-U-Sil 5 showed both contaminants introduced, on average, a positive error of < 5 microg with average recoveries of 106 percent and 111 percent, respectively. Spikes of mixtures of clay or concrete with Min-U-Sil 5 showed overall average recovery of 100 percent and 90 percent, respectively, after accounting for the presence of quartz in clay and concrete. This method can quantify low levels of quartz with reasonable accuracy in the face of common contaminants found in the construction industry.