火力发电厂粉尘接触量与尘肺发病关系的研究

为了研究火力发电厂粉尘与尘肺发病的剂量－反应关系,根据某火力发电厂接尘工人接尘时间、肺总通气量、粉尘浓度和游离二氧化硅含量,计算职工肺内石英负荷量,然后采用累积剂量患病率寿命表法研究尘肺患病率与粉尘的剂量－反应关系,推算该类粉尘的容许浓度。结果表明接尘剂量与尘肺患病率呈显著正相关关系,提示每人平均工作３０ａ,使尘肺患病率低于５‰,接触煤粉者和接触灰粉者作业场所平均粉尘浓度分别应控制在１０．００ｍｇ／ｍ３和３．２５ｍｇ／ｍ３以下。     

粉尘接触水平与脱尘矿工尘肺发病关系的研究

本文应用寿命表方法，对革金矿脱尘矿工粉尘接触水平与尘肺发病关系进行了研究，结果表明：随累积接尘量的增高，脱尘矿工尘肺患病率及累积患病率均依次递增，且差异显著（Ｐ〈０．０５或Ｐ〈０．０１）；累积拦尘量与尘肺患病之间存在剂量反应关系，若控制该职业人群尘肺累积发病率不超过５％，则作业场所空气中粉尘浓度就为３．５ｍｇ／ｍ＾３左右。     

砂轮制作工人接尘剂量—反应关系的研究

本文收集了某砂轮厂１９７３￣１９９１年粉尘测定资料，以及６１６例接尘者职业性体检资料。所研究的６１６例中，接尘者５７１例，尘肺患者４５例，采用寿命表法研究了砂轮作业工人接尘剂量与反应的关系，估算接尘３０年尘肺发病率小于１％时，砂轮粉尘浓度不超过７．５２ｍｇ／ｍ＾３，作者建议砂轮粉尘容许浓度为５ｍｇ／ｍ＾３为宜。     

上海石棉制品厂石棉肺接触反应关系研究

收集１９４９－１９９０年上海石棉制品厂石棉粉尘接触者的职业史，体检及车间尘浓度资料。研究对象为１０９１人，其接触者６２５人，病例４６６人，结果显示，该厂石棉肺患高达４２％，历年车间粉尘浓度明显超标。寿命表法确立了石棉粉尘接解－反应关系。估算接触３５年发病率小于１％时，接触粉尘浓度水平不超过３．６３ｍｇ／ｍ＾３。     

钨矿接尘工矽肺危险度

目的　探讨钨矿接尘工矽肺危险度并对其防治措施进行评价。方法　采用职业流行病学队列研究方法 ,按接尘水平进行定量分析和定性分析 ,估算钨矿接尘工矽肺危险度。结果　①接尘工累积接总粉尘不到 10mg/(m3 ·a) ,就有 45例矽肺发病 ,发病率为 0 7% ;②累积接总粉尘量与观察期矽肺发生差异有显著性 (P <0 .0 5 ) ;③钨矿矿尘空气中最高容许水平是 2mg/m3 ,相当累积呼吸性游离二氧化硅尘 0 0 41mg/(m3 ·a) ,此值在钨矿仍有病例发生。结论　我国当前采用的粉尘卫生标准在钨矿不是最低危害作用水平。同时也说明各类接尘厂矿的接触限值是有区别的。     

车间空气中麻尘（亚麻,黄麻和苎麻）卫生标准研制

根据现场卫生学调查、流行病学调查、动物实验、体外实验及剂量－反应关系的资料，并参考国外接触限值制订了麻尘（亚麻、黄麻和苎麻）卫生标准。调查结果发现，亚麻、黄麻和苎麻粉尘对人体危害不尽一致。亚麻粉尘可致工人发生棉尘病，黄麻尘可引起慢性支气管炎，其患病率与接尘量之间均存在剂量－反应关系，而苎麻尘危害较亚、黄麻尘为轻。本研究提出，车间空气中含有１０％以下游离二氧化硅的亚麻、黄麻和三麻粉尘最高容许浓度分别为３ｍｇ／ｍ￣３、４ｍｇ／ｍ￣３和６ｍｇ／ｍ￣３。     

隧道工矽肺危险度评价模型

目的：建立隧道工矽肺危险度评价模型，预测矽肺发病规律。方法：调查有关工程局5482名接尘工人的接尘史、隧道粉尘资料和矽肺病人的诊断日期；应用Kaplan-Meier方法初步估计累积患病率善于累积接尘量的曲线；应用样条函数方法拟合曲线。结果：建立了矽肺的危险度评价模型；提出矽尘作业30年不发生矽肺的粉尘最高容许浓度建议值0.21mg/m^3；在平均粉尘浓度20.47mg/m^3下工作30年，矽肺累积患病率预计为11．1％；接尘工龄30年，累积患病率控制为0.5%时，容许浓度为1.14mg/m^3；累积患病率控制为1％时，容许浓度为2.06mg/m^3。结论：建立的模型具有实用价值，得到的结果可以为行政管理部门制定规章制度、保护工人的健康提供决策依据。     

隧道工现场粉尘容许浓度的估算

目的 为估算铁路隧道作业现场的最高容许浓度提供参考依据。方法 利用肺内粉尘存留量反推法（检测一法）和以累计接尘时间为权重的调整的阈限值法（检测二法）估算铁路隧道粉尘作业的粉尘容许浓度。结果 得到预期接尘工龄为３０年，控制患病率分别在０．５％、１％水平的隧道现场粉尘浓度的估算值。检测一法：０．１５７８ ｍｇ／ｍ３和０．０９５４ ｍｇ／ｍ３；检测二法５．４１６１ｍｇ／ｍ３和１０．８３２２ ｍｇ／ｍ３。结论 为推动我国铁路系统粉尘作业现场容许浓度的流行病学调查，也为我国修订粉尘卫生标准提供参考依据。     

皮毛加工工人粉尘接触水平与肺功能损害的关系

对２１２名接触皮毛粉尘工人与２０７名对照工人进行了肺功能检测。并对累积接尘量与肺功能损害的关系进行了分析。结果表明，接尘组肺功能各项指标（ＦＶＣ、ＦＥＶ１、Ｖ５０、Ｖ２５）的实测值占预计值％均较对照组为低。肺功能损害随累积接尘量的增加而加重（Ｐ＜０．０１），肺功能异常率则随累积接尘量增加而增高（Ｐ＜０．０１）。多因素分析表明，接尘是影响肺功能下降的主要因素，吸烟也与肺功能呈负相关关系。皮毛粉尘接触水平与肺功能损害呈明显的接触水平－反应关系。据此本文推荐了皮毛粉尘的接触限值。     

职业医学

04 2 12 4　广西锡矿矿尘致矽肺的危险度评价 /张华生…∥中华劳动卫生职业病杂志 2 0 0 2 ,2 0 ( 6 ) 4 30～4 32探索锡矿矿尘的致病强度和最低无害作用水平。选择广西锡矿 196 0～ 1974年期间接触矿尘至少 1年的男性矿工 4 471名建立回顾性接尘队列 ,并用以同一方法建立的瓷厂接尘队列与其进行比较 ;采用SAS中的生存检验分析软件进行非参数估算 ,评价锡矿矿尘致矽肺的危险度。结果 ,随访到 1994年底 ,锡矿队列工人矽肺发病 971例 ( 2 1 7% ) ,其中 81%的病例为19 58年前接尘对象 ,累积接触总粉尘量 (CTD)与矽肺危险度明显相关 :当C…     

广西锡矿矿尘致矽肺的危险度评价

目的　探索锡矿矿尘的致病强度和最低无害作用水平。方法　选择广西锡矿 1 960～1 974年期间接触矿尘至少 1年的男性矿工 4 471名建立回顾性接尘队列 ,并用以同一方法建立的瓷厂接尘队列与其进行比较 ;采用SAS中的生存检验分析软件进行非参数估算 ,评价锡矿矿尘致矽肺的危险度。结果　随访到 1 994年底 ,锡矿队列工人矽肺发病 971例 (2 1 .7% ) ,其中 81 %的病例为 1 958年前接尘对象 ,累积接触总粉尘量 (CTD)与矽肺危险度明显相关 :当CTD <50mg·m- 3·年 - 1 时 ,矽肺危险度为 0 .0 1 2 ;CTD >40 0mg·m- 3·年 - 1 时 ,矽肺危险度上升到 0 .971。瓷厂接尘工人CTD >40 0mg·m- 3·年 - 1 时 ,矽肺危险度仅为 0 .369。结论　锡矿接触矿尘工人的矽肺发病与CTD明显相关 ;锡矿矿尘导致矽肺的危险性远比瓷厂的陶瓷尘严重     

Risk of silicosis in a cohort of white South African gold miners

The risk of silicosis was investigated in a cohort of 2,235 white South African gold miners who had, on average, 24 years of net service from 1940 to the early 1970s and who were followed up to 1991 for radiological signs of onset of silicosis (ILO category 1/1 or more). There were 313 (14%) miners who developed signs of silicosis at an average age of 55.9 years. The latency period was largely independent of the cumulative dust exposure. In 57% of the silicotics, the radiological signs developed, on average, 7.4 years after mining exposure ceased. The risk of silicosis increased exponentially with the cumulative dust dose, the accelerated increase being after 7 mg/m³-years. At the highest exposure level of 15 mg/m³-years, which represents approximately 37 years of gold mining at an average respirable dust concentration of 0.4 mg/m³, the cumulative risk for silicosis reached 77%. In conclusion, the risk of silicosis was strongly dose dependent; however, the latency period was largely independent of the dose. © 1993 Wiley-Liss, Inc.     

Risk of pulmonary tuberculosis relative to silicosis and exposure to silica dust in South African gold miners [published erratum appears in Occup Environ Med 1999 Mar;56(3):215-6]

OBJECTIVES: To investigate the following questions. (1) Is silica dust on its own, without the presence of silicosis, associated with an increased risk of pulmonary tuberculosis (PTB) in workers exposed to silica dust? (2) In the absence of silicosis is the excess risk dose related? (3) What is the predominant chronological sequence between the development of PTB and the development of silicosis after the end of exposure to dust? METHODS: A cohort of 2255 white South African gold miners has been followed up from 1968 to 1971, when they were 45-55 years of age, to 31 December 1995 for the incidence of PTB. During the follow up 1592 (71%) men died. Of these, 1296 (81%) had a necropsy done at the National Centre for Occupational Health (NCOH) to determine the presence of silicosis and PTB. The incidence of PTB in the cohort was studied relative to cumulative exposure to dust and the onset of silicosis. For the miners with necropsy, the incidence for PTB was studied relative to the severity of silicosis found at necropsy. RESULTS: There were 115 subjects who developed PTB. The total person- years of follow up was 39,319. For the whole cohort, the factors associated with increased risk of PTB were cumulative exposure to dust (mg/m3.y) (the adjusted rate ratio (RR) 1.07; (95% confidence interval (95% CI) 1.04 to 1.10)), silicosis diagnosed radiologically (3.96 (2.59 to 6.06)), and tobacco pack-years (1.02 (1.01 to 1.03)). The RR (95% CI) for PTB increased with increasing quartiles of cumulative exposure to dust 1.0, 1.51 (0.78 to 2.91), 2.35 (1.28 to 4.32), and 3.22 (1.75 to 5.90). In miners who did not have radiologically diagnosed silicosis (n = 1934, PTB = 74), the adjusted RR (95% CI) for PTB and cumulative exposure to dust was 1.10 (1.06 to 1.13), and increased with quartiles of cumulative exposure to dust as 1.00, 1.46 (0.70 to 3.03), 2.67 (1.37 to 5.23), and 4.01 (2.04 to 7.88). For the subjects who had a necropsy (n = 1296, PTB = 70), the adjusted RR (95% CI) for PTB increased with the severity of silicosis found at necropsy; 1.0 for no silicosis, 1.88 (0.97 to 3.64) for negligible, 2.69 (1.35 to 5.37) for slight, and 2.30 (1.16 to 4.58) for moderate or marked silicosis. For subjects who had a necropsy and no silicosis (n = 577, PTB = 18), the adjusted RR (95% CI) increased slightly with quartiles of cumulative dust 1.0, 1.11 (0.31 to 4.00), 1.42 (0.43 to 4.72), and 1.38 (0.33 to 5.62). CONCLUSION: Exposure to silica dust is a risk factor for the development of PTB in the absence of silicosis, even after exposure to silica dust ends. The risk of PTB increases with the presence of silicosis, and in miners without radiological silicosis, with quartiles of exposure to dust. The severity of silicosis diagnosed at necropsy was associated with increasing risk of PTB and even < 5 nodules--that is, undetectable radiologically--was associated with an increased risk of PTB. The diagnosis of PTB was on average 7.6 years after the end of exposure to dust, at around 60 years of age. The onset of radiological silicosis preceded the diagnosis of PTB in 90.2% of the cases with PTB who had silicosis. The results have implications for medical surveillance of workers exposed to silica dust after the end of exposure.       

Exposure to silica and silicosis among tin miners in China: exposure-response analyses and risk assessment

OBJECTIVES—To investigate the risk of silicosis among tin miners and to investigate the relation between silicosis and cumulative exposure to dust (Chinese total dust and respirable crystalline silica dust).
METHODS—A cohort study of 3010 miners exposed to silica dust and employed for at least 1 year during 1960-5 in any of four Chinese tin mines was conducted. Historical total dust data from China were used to create a job exposure matrix for facility, job title, and calendar year. The total dust exposure data from China were converted to estimates of exposure to respirable crystalline silica for comparison with findings from other epidemiological studies of silicosis. Each worker''s work history was abstracted from the complete employment records in mine files. Diagnoses of silicosis were based on 1986 Chinese pneumoconiosis Roentgen diagnostic criteria, which classified silicosis as stages I-III—similar to an International Labour Organisation (ILO) classification of 1/1 or greater.
RESULTS—There were 1015 (33.7%) miners identified with silicosis, who had a mean age of 48.3 years, with a mean of 21.3 years after first exposure (equivalent to 11.0 net years in a dusty job). Among those who had silicosis, 684 miners (67.4%) developed silicosis after exposure ended (a mean of 3.7 years after). The risk of silicosis was strongly related to cumulative exposure to silica dust and was well fitted by the Weibull distribution, with the risk of silicosis less than 0.1% when the Chinese measure of cumulative exposure to total dust (CTD) was under 10 mg/m³-years (or 0.36 mg/m³-years of respirable crystalline silica), increasing to 68.7% when CTD exposure was 150 mg/m³-years (or 5.4 mg/m³-years of respirable crystalline silica). Latency period was not correlated to the risk of silicosis or cumulative dose of exposure. This study predicts about a 36% cumulative risk of silicosis for a 45 year lifetime exposure to these tin mine dusts at the CTD exposure standard of 2 mg/m³, and a 55% risk at 45 years exposure to the current United States Occupational Safety and Health Administration and Mine Safety and Health Administration standards of 0.1 mg/m³ 100% respirable crystalline silica dust.
CONCLUSIONS—A clear exposure-response relation was detected for silicosis in Chinese tin miners. The study results were similar to most, but not all, findings from other large scale exposure-response studies.


     

FAS和FASL基因多态性与矽肺易感性的关系

目的 探讨FAS和FASL基因多态性与矿工矽肺遗传易感性的关系.方法 采用病例对照设计,以183例男性矽肺患者为病例组,111例无矽肺的男性接尘矿工为对照组,调查研究对象的一般情况及职业史,收集现场粉尘浓度资料,估算工人既往累积总粉尘接触量;应用聚合酶链反应一限制性片段长度多态性分析(PCR-RFLP)技术检测FAS-1377、FAS-670及FASL-844位点的多态性,分析多态性与矽肺患病及矽肺期别的关系,基因间以及基因与环境因素间的交互作用以及单倍型.结果 FAS-1377、FAS-670及FASL-844各位点基因型在病例组和对照组间的分布差异均无统计学意义(P》0.05);不同期别矽肺患者中FAS-1377、FAS-670及FASL-844位点多态分布差异无统计学意义(P》0.05);病例组中FAS-1377G/-670G单倍型分布频率为9.6%,明显高于对照组(3.6%),差异有统计学意义(P《0.05);各基因多态间、基因多态与累积总粉尘接触量以及基因多态与吸烟状况之间的交互作用分析结果均无统计学意义(P》0.05).结论 FAS-1377、FAS-670及FASL-844多态性在矽肺发病的遗传易感性中不起主要作用.单倍型FAS-1377G/-670G可能是矽肺发生的易感性标记.     

Risk of silicosis in cohorts of Chinese tin and tungsten miners, and pottery workers (I): an epidemiological study

BACKGROUND: Epidemiological evaluations of the risk of silicosis in relation to exposure to crystalline silica have raised the question of whether different types of silica dust exposures vary with respect to their ability to cause silicosis. The aim of this study is to compare the risk of silicosis among cohorts of silica dust-exposed Chinese tin miners, tungsten miners, and pottery workers and to assess whether gravimetric measurements of respirable silica dust sufficiently determine the risk of silicosis or whether other factors of exposure may play a significant role. METHODS: Cohorts were selected from 20 Chinese mines and potteries. Inclusion criteria were starting employment after January 1, 1950 and being employed for at least 1 year during 1960-1974 in one of the selected workplaces. Radiological follow-up for silicosis onset was from January 1, 1950 through December 31, 1994. Silicosis was assessed according to the Chinese radiological criteria for diagnosis of pneumoconiosis (as suspect, Stage I, II, or III). Exposure-response relationships were estimated for silicosis of Stage I or higher. Silica dust exposure was estimated in terms of cumulative total dust exposure, calculated from a workplace, job title, and calendar year exposure matrix, and individual occupational histories. Cumulative total dust exposure was converted in two steps into cumulative respirable dust exposure and cumulative respirable silica dust exposure using conversion factors estimated from side-by-side measurements conducted in 1988-89. RESULTS: The male cohorts included 4,028 tin miners, 14,427 tungsten miners, and 4,547 pottery workers who had similar onset of employment and duration of follow-up. For a given exposure level, the risk of silicosis was higher for the tin and tungsten than the pottery workers. CONCLUSION: The observed differences in the risk of silicosis among the three cohorts suggest that silica dust characteristics, in addition to cumulative respirable silica dust exposure, may affect the risk of silicosis.     

Exposure-response of silicosis mortality in Swedish iron ore miners

OBJECTIVES: To assess the exposure-response relationship between exposure to quartz and fatal silicosis. METHODS: The mortality from silicosis in 7729 miners was analyzed and compared to their estimated exposure to respirable quartz. The miners had been working as a miner for at least 1 year between 1923 and 1996. Their mortality between 1952 and 2001 was studied by using information from the national cause of death register. Both underlying and contributing causes of death were considered in the analysis. The exposure to quartz was estimated from job titles and using 3239 measurements of personal exposure to respirable quartz from 1965 to 1999. The mortality rates were adjusted to attained age and years of birth using a Poisson regression. RESULTS: The median cumulative exposure among the 7729 miners was 0.9 mg x years m(-3). There were 58 deaths from silicosis. Their median cumulative exposure was 4.8 mg x years m(-3). The crude mortality rate was 53 cases per 100,000 person-years with an exposure-response relationship. CONCLUSION: There seems to be an increased risk of fatal silicosis at exposure levels around 3 mg x years m(-3) for respirable quartz.     

肺癌病因研究中接尘量计算的真实性评价

为评价肺癌病例对照研究中接尘剂量估算方法的真实性,对广西锡矿病因研究对象进行了重新计算。广西锡矿队列发现男性肺癌死者１３０例,配对照６２７例。共７５７人。其中接法工人５７２名,发现各期矽肺共２４３例,根据在斩工业卫生监测资料估算所有接尘工人的累积总粉尘接触量,再计算不同接尘水平下矽肺的发病率。结果显示,随接尘水平上升,矽肺发病率升高,两者存在明显的接触剂量反应关系。完全符合矽肺发病特点。从而间接证     

Association between lymph node silicosis and lung silicosis in 4,384 German uranium miners with lung cancer

This study investigates the association between lymph node-only and lung silicosis in uranium miners with lung cancer and exposure to quartz dust. Tissue slides of 4,384 German uranium miners with lung cancer were retrieved from an autopsy archive and reviewed by 3 pathologists regarding silicosis in the lungs and lymph nodes. Cumulative exposure to quartz dust was assessed with a quantitative job-exposure matrix. The occurrence of silicosis by site was investigated with regression models for exposure to quartz dust. Miners with lung silicosis had highest cumulative quartz exposure, followed by lymph node-only silicosis and no silicosis. At a cumulative quartz exposure of 40 mg/m(3) × years, the probability of lung silicosis was above 90% and the likelihood of lymph node-only silicosis and no silicosis do not differ anymore. The results support that lymph node silicosis can precede lung silicosis, at least in a proportion of subjects developing silicosis, and that lung silicosis strongly depends on the cumulative quartz dose.     

Risk of silicosis in a Colorado mining community

We investigated exposure-response relations for silicosis among 134 men over age 40 who had been identified in a previous community-based random sample study in a mining town. Thirty-two percent of the 100 dust-exposed subjects had radiologic profusions of small opacities of 1/0 or greater at a mean time since first silica exposure of 36.1 years. Of miners with cumulative silica exposures of 2 mg/m³-years or less, 20% had silicosis; of miners accumulating > 2 mg/m³-years, 63% had silicosis. Average silica exposure was also strongly associated with silicosis prevalence rates, with 13% silicoties among those with average exposure of 0.025–0.05 mg/m³, 34% among those with exposures of > 0.05–0.1 mg/m³, and 75% among those with average exposures > 0.1 mg/m³. Logistic regression models demonstrated that time since last silica exposure and either cumulative silica exposure or a combination of average silica exposure and duration of exposure predicted silicosis risk. Exposure-response relations were substantially higher using measured silica exposures than using estimated silica exposures based on measured dust exposures assuming a constant silica proportion of dust, consistent with less exposure misclassification. The risk of silicosis found in this study is higher than has been found in workforce studies having no follow-up of those leaving the mining industry and in studies without job title-specific silica measurements, but comparable to several recent studies of dust exposure-response relationships which suggest that a permissible exposure limit of 0.1 mg/m³ for silica does not protect against radiologic silicosis. © 1996 Wiley-Liss, Inc.