石棉工人肺弥散量和通气功能的探讨

本文采用一次呼吸CO法,测定了315名石棉工人和314名作为对照的不接尘健康工人的弥散量,并测定了通气功能。与对照组相比,男、女石棉工人弥散量(DLco),肺活量(VC),用力肺活量(FVC)和一秒时间肺活量(FEV_1)明显降低;一秒率(FEV_1%)和呼气中期流速(MMEF)没有明显差异。石棉工人最早出现的肺功能异常是DLco降低。DLco与接尘工龄存在负相关关系,说明接触石棉的时间是影响石棉工人DLco的一个重要因素。石棉工人肺弥散功能和通气功能损害都早于X线胸片的改变,DLco、VC、FVC、FEV_1是早期反映石棉对肺部损害的敏感、稳定的指标。建议将弥散量和通气功能测定作为石棉肺的诊断参考和劳动能力鉴定的客观依据。     

石棉工人肺功能损害的敏感指标研究

目的：探讨石棉工人肺功能损害的最敏感指标。方法：对某石棉制品厂石棉工人和石棉肺患者分别于１９８４、１９８９及１９９４年进行了三次的肺功能（ＶＣ、ＦＶＣ、ＦＥＶ、ＦＥＶ１％、ＤＬｃｏ和ＲＶ／ＴＬＣ％）追踪观察。结果：两组均随接尘时间的增长,肺通气功能（ＶＣ、ＦＶＣ、ＦＥＶ１及ＦＥＶ１％）和弥散功能（ＤＬＣＯ）进行性损害;石棉肺患者弥散功能的进行性损害快于石棉工人;从变化值上看,下降速度较大的指标为ＤＬＣＯ和ＦＶＣ。结论：石棉工人肺功能变化的最敏感指标为ＦＶＣ和ＤＬＣＯ。     

吸烟对石棉工人肺功能影响的动态研究

[目的]探讨吸烟对石棉工人肺功能变化的动态影响特点。[方法]对某石棉制品厂吸烟与非吸烟石棉工人（包括健康石棉工人和石棉肺患者）分别于1984年、1989年及1994年进行了3次的肺功能（VC、FVC、FEV1、FEV1%、DLCO和RV/TLC%追踪观察。[结果]吸烟组与非吸烟组石棉工人VC、FVC、FEV1和DLCO均随接尘年限的增加而下降,FEV1%随接尘年限的增加而上升,且吸烟组这些指标测定均低于非吸烟组（除个别外）,均显示出渐近性损害的特点。但没有显示出吸烟组肺功能值的下降比非吸烟组更快。[结论]石棉粉尘对石棉作业工人肺功能的损害起主要作用,可能掩盖了吸烟对肺功能的影响。     

石棉粉尘接触剂量与肺功能反应关系

对204名石棉造纸工人进行了肺功能测定,并与116名一般造纸工人对比,发现石棉工人VC及FVC%随接尘量(根·年)的增加而降低,因此认为石棉纤维计数浓度累计接尘量与肺容量变化存在剂量—反应关系。闭合容量测定中Ⅲ相斜率的异常率亦随累计接尘量而增加,认为是肺组织弹性回缩力下降所致。建议Ⅲ相斜率可用于石棉工人体检作为石棉尘影响及肺弹性变化的观察指标。     

石棉工人肺通气功能变化的追踪研究

本研究通过对某石棉制品厂73例男性工人（其中健康石棉工人37例，石棉肺患者36例）分别于1984、1989及1994年进行了三次肺通气功能追踪测定，结果表明：石棉工人肺通气功能动态变化的特点是VC、FVC和FEV，进行性降低，FEV1／FVC％显著增高；石棉工人肺通气功能改变的早期阶段在接触石棉粉尘后10～15年期间；其肺通气功能损害的基本类型是限制型，在平均接尘15年后显示出典型的限制型特征。     

矽肺、石棉肺、煤工尘肺肺功能研究

本文测定了592名接触矽尘、石棉尘、煤(矽)尘的工人和425名尘肺病人及206名健康不接尘工人的肺功能,建立了接尘工人肺通气功能和换气功能预计值回归公式,比较研究了接触不同粉尘的工人和尘肺病人的肺功能变化和临床症状发生率,表明不同粉尘对工人和尘肺病人肺功能影响有所不同。接触矽尘的工人和矽肺病人各项指标都降低,矽肺病人肺气肿和临床症状发生率与功能变化较一致。煤矿工人和煤工尘肺病人FEV_1/FVC%下降较明显,呼吸道症状也较突出,但肺气肿诊断率与RV/TLC%都较低。石棉工人和石棉肺病人VC和DLco变化似较其他指标更明显。     

矽肺石棉肺煤工尘肺肺功能研究

对592名接触矽尘、石棉尘、煤(矽)尘的工人和425名尘肺病人以及206名健康不接尘工人的肺功能进行了测定,建立了肺通气功能和换气功能预计值回归公式。比较研究了接触不同粉尘的工人和尘肺病人的肺功能损害程度及其特点,表明尘肺病人各项肺功能指标明显低于接尘工人;矽肺病人中混合性肺功能损害者较多,石棉肺病人限制性损害较明显,而煤工尘肺病人则多表现为阻塞性的功能损害。     

新疆高原石棉作业工人肺功能调查

对新疆某高原石棉矿191名接尘作业工人和生活区69名非接尘工人进行了肺功能检查。结果表明：高原石棉矿接尘工人与非接尘工人各项测试指标均偏高，接尘工人肺功能随接尘工龄的增加而逐步下降，病例组肺功能异常率高于其它组，肺功能异常与吸烟关系不明显。     

接触石棉尘量与石棉肺发病的剂量-反应关系研究

目的：探讨乡镇石锦加工人员接触石棉尘量与石棉肺发病的剂量－反应关系。方法：记录接尘工人的职业史,体检史,纤维计数浓度由质量浓度通过公式换算得到,累积接尘量由接触浓度与时间相乘所得,以寿命表法建立石棉尘质量浓度与纤维计数浓度的剂量患病概率直线回归方程式。结果： 按1％石棉肺患病率,工人30年工作年限计算,预测石棉尘质量浓度与纤维计数浓度应低于2．71mg/m3与1．93f/ml,结论：现行国家石棉尘卫生标准是合理的。     

接触木尘工人与脱尘工人肺功能的配对研究

为深入研究木尘对接尘工人肺功能的影响，我们按照配对设计原则，对某厂木型车间接触木尘工人与脱离木尘作业工人分别进行了肺通气功能的配对比较分析。结果表明，无论是接尘组工人，还是离尘组工人，其ＦＶＣ、ＦＥＶ１、ＭＭＦ、Ｖ５０与Ｖ２５等肺功能各项指标的实测值，均较对照组明显降低，且多具有显著的统计学意义。累计接尘量与肺功能各指标实测值／预计值百分比间存在着一定的剂量－反应关系，即随着累计接尘量增加肺功能损害加重。多因素分析显示：累计接尘量是致接尘工人肺功能下降的主要因素。提示接尘工人、脱离木尘作业工人肺通气功能的损害与木尘有关。     

胸膜增厚对石棉工人肺功能的影响

[目的]探讨胸膜增厚对石棉工人肺功能的影响。[方法]接触组为某温石棉厂134名男性工人，对照组为同一地区不接触粉尘、劳动强度与接触组大体相似的某仪表厂135名男性工人。对两组对象的肺功能测定和后前位X射线胸片检查结果进行对比分析。[结果]与对照组相比，在控制了肺内小阴影改变和累积吸烟量等混杂因素的影响后，石棉接触工人中胸膜正常细和双侧胸膜增厚组用力肺活量（FVC）和一秒钟用力呼气容积（FEV1）均显著下降（P〈0．05），单侧胸膜增厚组仅FVC显著下降（P〈0．05）；而与胸膜正常组相比，在控制了肺内小阴影改变、累积吸烟量和接尘年限等混杂因素的影响后，双侧胸膜增厚组FVC和FEV1显著下降（均为P〈0．05）；在控制了肺内小阴影改变、累积吸烟量和接尘年限等混杂因素的影响后，胸膜增厚范围与FVC呈负相关，与弥散系数（Kco）呈正相关（均为P〈0．05）。[结论]胸膜增厚范围越大，肺功能损害也越严重，呈限制性肺功能障碍的特征。     

Pulmonary function in long-term asbestos workers in China

The relationship of pulmonary function to exposure to asbestos and radiographic abnormalities has been controversial, especially when smoking is present as a confounder. The aim of the study was to provide further understanding on the radiographic-physiologic associations in nonsmoking and smoking asbestos workers. Radiographic asbestosis, pleural lesion, and pulmonary function were studied in 269 Chinese asbestos workers, with average exposure years of 23 for male workers and 18 for female workers. Their functional data were compared with those of 274 controls without exposure to dust. Although most of the male workers were smokers, none of the female workers smoked. In comparison with controls, asbestos workers had significantly lower lung volume and diffusing capacity, irrespective of gender. Female workers and smoking male workers had lower measurements of forced expiratory volume in 1 second and instantaneous forced expiratory flow at 50% and 25% of forced vital capacity. After adjustment for relevant covariates, asbestos exposure, asbestosis, and pleural abnormalities were associated with decreased parameters of pulmonary function, including lung volume, diffusing capacity, and airway flow. These data indicate that asbestos-related functional defects manifested by lung restriction and mild airway obstruction correlate with exposure to asbestos and with parenchymal and pleural abnormalities, independent of smoking.     

Respiratory impairments due to dust exposure: A comparative study among workers exposed to silica,asbestos, and coalmine dust

We conducted a comparative study of pulmonary dysfunction among workers who were exposed to silica, asbestos, or coalmine dust. The results showed that all three groups of dust-exposed workers, even those without radiographic signs of pneumoconiosis, had decreased spirometric parameters and diffusing capacity (DLco) in both nonsmokers and smokers. Pulmonary function was further decreased when pneumoconioses were present in the three groups. In accord with increasing radiographic categories, pulmonary function in the workers' pneumoconiosis (CWP), it changed relatively little. Workers with mild to moderate (radiographic category I–II) silicosis or asbestosis showed similarly decreased DLco, but those with silicosis showed lower FEV₁/FVC than those with asbestosis. The workers with CWP also showed a lower FEV₁/FVC than those with asbestosis. The major impairment patterns for silica workers, asbestos workers, and coal miners were mixed, restrictive and mixed, and obstructive, respectively. Smoking obviously increased the prevalence of obstruction for all the groups. We conclude from the present study that all the three dusts cause functional abnormalities that precede radiographic changes of pneumoconiosis. We should pay more attention to respiratory impairment in the initial stage of silicosis and CWP. Am. J. Ind. Med. 31:495–502, 1997. © 1997 Wiley-Liss, Inc.     

High prevalence of reversible airway obstruction in asbestos-exposed workers

In this retrospective study of 97 male workers exposed to asbestos for 2-50 yr, data were collected on chest x-ray findings and lung function, including lung volumes, forced expiratory flow rates (i.e., forced expiratory volume in 1 sec [FEV1.0], forced expiratory flow measured between 25% and 75% of forced vital capacity [FEF(25-75%)]), airway resistance (R(aw)), carbon monoxide (CO)-diffusing capacity, and the existence of airway obstruction reversible by a beta-adrenergic agonist (RAO). The authors performed multiple-regression analyses to correlate the variations in lung function data with age, smoking habits, duration of asbestos exposure, and time since last exposure. Occupational activities of subjects that might induce specific lung abnormalities were also considered. No significant decrease was seen in lung volumes or CO-diffusing capacity; however, a decrease in FEV1.0 and an increase in R(aw) were measured in 65% of the subjects, and an isolated decrease in FEF(25-75%) occurred in only 18%. There was no difference in lung-function data between subjects who had chest x-ray signs of abnormalities (n = 59) and those who did not (n = 38). A significant relationship was found between the decrease in FEV1.0 and age; however, no correlation was noted between altered lung function and cigarette smoking, duration of asbestos exposure, or time since last exposure. RAO prevalence was higher (34%) than previously reported (9%) in subjects with chronic obstructive pulmonary disease (COPD) who were not exposed to asbestos or outdoor pollution. The RAO prevalence in asbestos-exposed workers was nearly the same as that measured in COPD subjects who lived downtown and who were exposed to outdoor pollution (36%). The high RAO prevalence in asbestos-exposed workers was found in 43% of subjects who were exposed only to asbestos, and in 33% of subjects who were also exposed to air pollution due to their occupational activities. It is hoped that the observations in this study will encourage practitioners to check for RAO in asbestos workers who use inhaled bronchodilators.     

某煤矿掘砌工人肺通气功能分析

[目的]了解煤矿掘砌工人肺通气功能损伤情况,探讨接尘工龄对肺功能的影响。[方法]。选取某煤矿纯掘砌工（纯掘砌作业工人）221名作为接尘组,选取该矿83名非接尘工人作为对照。行统一的体检和肺功能测定。测定结果均采用相对值,运用卡方检验、协方差分析进行统计学处理。[结果]接尘组非吸烟工人肺通气功能异常率与对照组差异不具有统计学意义（P〉0．05）,而接尘组吸烟工人肺通气功能异常率高于对照组（P〈0．05）。Mantel—Haenszel妒分析显示接尘组肺通气功能异常率高与对照组（P〈0．05）。以吸烟作为协变量,协方差分析结果显示,接尘组的用力肺活量、第一秒用力呼出量、呼气高峰流量、用力肺活量最大值、第一秒用力呼出量最大值明显低于对照组（尸〈0．05）。以吸烟为协变量,协方差分析结果显示,接尘组30年一工龄组呼气高峰流量和25％肺活量最大呼气流量明显低于10年～工龄组和20年～工龄组。以吸烟为分层因素,接尘组与对照组以及接尘组不同工龄间慢性阻塞性肺疾患患者分布差异均无统计学意义（P〉0．05）。[结论]掘砌作业工人肺通气功能明显低于对照组并随接尘工龄延长而降低。肺通气功能检测可以作为监测接尘作业工人肺部损失的指标。     

石棉工人肺功能与X射线胸片变化关系的研究

目的 探讨石棉工人肺功能与X射线胸片变化之间的关系。为早期发现石棉肺和对石棉肺患者肺代偿功能评价提供客观依据。方法 接触组为某温石棉制品厂134名男工，对照组为同一地区不接触粉尘，劳动强度与研究组工人大体相似的某仪表厂135名男工，对肺功能测定和X射线胸片检查结果进行对比分析。结果 胸膜和肺组织均有纤维化者，肺功能均明显下降。呈混合性肺功能障碍的特点；弥漫性胸膜增厚则与FVC，FEV1.0,FEV1.0/FVC%,DLco和Kco均呈显著负相关（r值分别为-0.20,-0.26,-0.21,-0.27,-0.19)。单纯胸膜斑与Kco呈正相关（r=0.23)；胸膜病变范围越大，肺功能损害也越严重。呈限制性肺功能障碍的特征。结论 石棉工人肺代偿功能指标的异常。可以早期反映肺内纤维化和胸膜病变的程度和范围。     

Adverse effects of asbestos exposure and smoking on lung function

BACKGROUND: Exposure to asbestos is a well-recognized cause of both malignant and nonmalignant diseases of lung parenchyma and pleura. This study was conducted to determine the adverse effects of exposure to asbestos and smoking on pulmonary function. METHODS: Four hundred and sixty-eight workers who were occupationally exposed to asbestos for an average of 13 years were selected from an asbestos-product factory in China. Of them, 85 workers were diagnosed with asbestosis. Additionally, 282 workers who had no experience of exposure to industrial dust were included as a control group. A questionnaire was administered during a face-to-face interview and spirometric maneuvers and single-breath CO diffusing capacity (DL(CO)) were performed. RESULTS: Multivariate regression analysis showed that exposure to asbestos was more strongly associated with decreased forced vital capacity (FVC) and DL(CO), and asbestosis more strongly associated with decreased FVC, while smoking was a major contributing factor to reduced FEV1/FVC. The results were confirmed by a further analysis where the subjects were grouped exclusively by smoking, asbestos exposure, and chest radiographic changes. No interaction or joint effect was observed between asbestos exposure and smoking. CONCLUSIONS: This analysis suggested that asbestos and smoking might play independent roles, in which asbestos caused mainly a restrictive impairment, and smoking was a major causal factor for airway obstruction in the workers who were intensively exposed to asbestos.     

High Prevalence of Reversible Airway Obstruction in Asbestos-Exposed Workers

In this retrospective study of 97 male workers exposed to asbestos for 2-50 yr, data were collected on chest x-ray findings and lung function, including lung volumes, forced expiratory flow rates (i.e., forced expiratory volume in 1 sec [FEV_1.0], forced expiratory flow measured between 25% and 75% of forced vital capacity [FEF_25-75%]), airway resistance (R_aw), carbon monoxide (CO)-diffusing capacity, and the existence of airway obstruction reversible by a β-adrenergic agonist (RAO). The authors performed multiple-regression analyses to correlate the variations in lung function data with age, smoking habits, duration of asbestos exposure, and time since last exposure. Occupational activities of subjects that might induce specific lung abnormalities were also considered. No significant decrease was seen in lung volumes or CO-diffusing capacity; however, a decrease in FEV_1.0 and an increase in R_aw were measured in 65% of the subjects, and an isolated decrease in FEF_25-75% occurred in only 18%. There was no difference in lung-function data between subjects who had chest x-ray signs of abnormalities (n = 59) and those who did not (n = 38). A significant relationship was found between the decrease in FEV_1.0 and age; however, no correlation was noted between altered lung function and cigarette smoking, duration of asbestos exposure, or time since last exposure. RAO prevalence was higher (34%) than previously reported (9%) in subjects with chronic obstructive pulmonary disease (COPD) who were not exposed to asbestos or outdoor pollution. The RAO prevalence in asbestos-exposed workers was nearly the same as that measured in COPD subjects who lived downtown and who were exposed to outdoor pollution (36%). The high RAO prevalence in asbestos-exposed workers was found in 43% of subjects who were exposed only to asbestos, and in 33% of subjects who were also exposed to air pollution due to their occupational activities. It is hoped that the observations in this study will encourage practitioners to check for RAO in asbestos workers who use inhaled bronchodilators.     

Relation between lung function, exercise capacity, and exposure to asbestos cement

A group of 137 male workers with known exposure (mean 20 fibre years per millilitre) to asbestos cement who had symptoms or signs of pulmonary disease was studied together with a reference group of 49 healthy industrial workers with no exposure to asbestos. Lung function measurements were made at rest and during exercise. Evidence of lung fibrosis was found as well as of obstructive airways disease in the exposed group compared with the reference group. Asbestos cement exposure was related to variables reflecting lung fibrosis but not to variables reflecting airflow obstruction. Smoking was related to variables reflecting obstructive lung disease. Exercise capacity was reduced in the exposed workers and was related to smoking and to lung function variables, reflecting obstructive airways disease. There was no significant correlation between exercise capacity and exposure to asbestos cement.