陶瓷作业工人肺功能测试结果分析

目的了解陶瓷作业工人肺功能损害的情况,为预防尘肺病发生提供依据。方法选择某陶瓷厂200名接尘工人,平均年龄为（32.31±8.25）岁,另选取非接尘工人50名为对照组,平均年龄为（34.88±9.75）岁,采用意大利的spirolabII型的肺功能仪,测试的项目包括肺活量（VC）、用力呼吸肺活量（FVC）、第1s用力呼气量（FEV1）、一秒率（FEV1%）、最大呼气中段流速（FEF25-75）、最大呼气25%、50%、75%肺活量时流量（FEF25%、FEF50%、FEF75%）;应用SPSS13.0统计软件统计分析。结果接尘组的肺功能指标FEV1、FEV1%、FEF25-75、FEF50%、FEF75%明显低于对照组,差异有统计学意义（P〈0.05）;接尘工龄在10年～、15年～、20年～组的工人肺功能指标中VC、FVC、FEF25-75、FEF50%、FEF75%的测试均值明显低于接尘工龄〈5年组,差异有统计学意义（P〈0.05）。结论陶瓷粉尘对作业工人的肺功能有损害作用,且随着接尘工龄的增加肺功能受损害程度增加。     

A longitudinal study of lung function in jute processing workers.

A 5-y follow-up study of pulmonary function was conducted in 1982 and in 1987 for 50 current and retired jute-processing workers who had been employed for more than 10 y in a jute mill in China. Control subjects, who had no history of dust or gas exposure, were selected from a paper-packing plant in the same city. Forced expiratory maneuvers were conducted in the same manner in both 1982 and 1987. The jute workers' pulmonary functions, i.e., forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1.0), and forced expiratory flow (FEF25-75%), were more compromised than were pulmonary functions in the controls for the same 5-y period; however, only the increased incidence of abnormal FEV1.0s in jute workers was statistically significant. Male jute workers had significantly higher annual decrements of FVC, FEV1.0, and FEF25-75% than did control workers. Regression analysis indicated that in 1987, predicted values of FEV1.0 and FEF25-75% for the jute workers were related to years of employment. Our results suggest that long-term exposure to jute dust could produce chronic loss of lung function.     

小气道功能测定在粉尘作业人员职业健康监护及风险评估中的应用

[目的]了解粉尘作业对员工呼吸功能的影响,探讨小气道功能测定在粉尘作业人员职业健康监护及尘肺风险评估中的应用。[方法]2009年对某机械制造企业粉尘作业车间进行生产环境调查、粉尘浓度检测,对216名粉尘作业人员进行肺功能测定等职业健康检查及问卷调查。[结果]粉尘作业人员用力呼气75％肺活量的瞬间流量（forcedexpiratoryflowat75％offorcedvitalcapacity,FEF75％）的中位数为79％,低于正常值,用力肺活量（forcedvitalcapacity,FVC）、第1秒用力呼气容积（forcedexpiratoryvolumeinonesecond,FEV1）、1秒率（FEVl／FVC）、最高呼气流量（peakexpiratoryflow,PEF）、用力呼气25％肺活量的瞬间流量（forcedexpiratoryflowat25％FVC,FEF25％）、用力呼气50％肺活量的瞬间流量（forcedexpiratoryflowat50％ofFVC,FEF50％）的均数或中位数都在正常范围内,PEF、FEF25％、FEF50％和FEF75％异常的人员比例明显增高,分别为21．30％、BO．56％、45．37％和50．00％,而且这些参数异常人员接尘工龄较短,中位数分别为3．5年、4年、5年和5年。FVC、FEV1、FEV1／FVC、PEF、FEF25％、FEF50％、FEF75％异常人员的胸片检查异常比例分别为55．56％、60％．00、0、21．74％、15．15％、23．47％、25．00％。将胸片异常组与正常组的肺功能进行比较,胸片正常组的PEF、FEF25％、FEF50％的参数值低于异常组,差异有统计学意义（P〈0．05）。工龄10年以上的粉尘作业人员FEV1、FEF25％和FEF75％异常比例高于工龄较短组（P〈0．05）。[结论]粉尘作业人员存在气流受限、小气道功能障碍。随着接尘工龄的增加,FEV1、FEF25％和FEF75％异常人员有增多的趋势。该人群肺功能检查结果与胸片表现并不同步。在职业健康监护工作中,应对粉尘作业人员的肺功能尤其是小气道功能进行重点观察和动态对比分析,并将其作为尘肺风险评估的指标之一。建议在职业健康检查中将FEF25％、FEF50％、FEF75％等反映小气道功能的参数增设为监测指标。     

A follow-up study of respiratory function in workers exposed to acid aerosols in a food-processing industry

A follow-up investigation was performed on 49 female workers studied 2 years earlier in a vegetable-pickling plant. Acute and chronic respiratory symptoms and ventilatory capacity measurements were recorded during the original and the follow-up studies. Maximal expiratory flow-volume (MEFV) curves were recorded during the Monday morning work shift. The forced vital capacity (FVC), 1-s forced expiratory volume (FEV1), and flow rates at 50% and the last 25% of the FVC (FEF50, FEF25) were measured. There were small increases in the prevalence of chronic symptoms between the two studies for both smokers and nonsmokers, but these did not reach statistical significance. Five workers at the time of the initial study had a diagnosis of occupational asthma; only one of these was still working at the time of follow-up. Workers lost to the follow-up had lower lung function than those seen at follow-up. In workers who were followed, larger than expected mean annual declines were noted for all ventilatory capacity parameters in both smokers (FVC 0.070 l, FEV1 0.070 l; FEF50 0.355 l/s, FEF25 0.270 l/s) and nonsmokers (FVC 0.045 l, FEV1 0.045 l, FEF50 0.285 l/s; FEF25 0.130 l/s). The decrease was particularly pronounced for FEF50 and FEF25. The accelerated decline in ventilatory capacity tests noted in the female nonsmokers suggests an independent effect on lung function of work exposure in this environment. Our data confirm that work in the pickling industry, particularly in small, poorly regulated plants, has deleterious effects on respiratory function. Received: 24 September 1996 / Accepted: 19 June 1997     

矽肺患者肺功能分析

目的探讨矽肺患者肺功能受损情况。方法对57例矽肺患者最大肺活量（VCmax）,用力肺活量（FVC）,1秒时间用力呼出量（FEV1）,1秒时间用力呼出量与用力肺活量之比（FEV1／FVC）,最大呼气中期流速（MMEF）,25％、50％、75％肺量时的最大呼气流量（V25、V50、V75）,肺总量（TLC）,残气量（RV）,残总比（RV／TLC）,肺弥散量（DLCO）等肺功能指标进行测定分析。结果I期与Ⅱ期矽肺患者肺功能损伤以混合型为主,且I期矽肺患者FEV1％、FEV1／FVC、V25、V50、MMEF测定值与Ⅱ期矽肺患者比较,差异有统计学意义（P〈0．05）。结论矽肺患者肺功能损伤明显,且随矽肺期别增加而加重,损伤类型以混合为主。Ⅱ期矽肺患者大、小气道的阻塞较I期矽肺病人加重。     

惠州市某区宝石加工作业工人肺功能测定分析

目的了解惠州市某区宝石加工作业工人的肺功能损害情况。方法 2009年7月惠阳区疾病预防控制中心对该区宝石加工厂接尘工龄1a以上的214名男工进行肺功能测定,其中切石工人127例,打磨工人87例;另选择该厂的61名非接尘男工作为对照组;并对宝石加工厂空气中粉尘浓度进行测定。结果该宝石加工厂空气中矽尘浓度超标率超过77%,最高超标为9倍。矽尘中游离SiO2含量平均为47.29%。接尘组肺通气功能的异常率显著高于对照组(P0.01),用力肺活量(FVC)、第1秒用力肺活量(FEV1.0)、第1秒用力肺活量与用力肺活量之比(FEV1.0/FVC)、肺活量(VC)、最大呼气中期流速(FEF25-75)、最大呼气25%、50%、75%肺活量时流量(FEF25、FEF50、FEF75)均明显低于对照组(P0.01)。结论该宝石加工作业粉尘可致工人肺功能一定程度的损伤,应做好预防工作。     

Changes in lung function of children after an air pollution decrease

Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1.0), forced expiratory flow between 25 and 75% of FVC (FEF25-75), and maximal expiratory flow at 50% of FVC (MEF50) were measured in 1,880 school children who lived in urban areas before and after a decrease of air pollution. A group of 162 children from a suburban area served as controls. In the first survey, FEV1.0, FEF25-75, and MEF50 of children from urban areas were significantly lower, while in the second survey they were not significantly different from those of controls. The slopes over time of FEV1.0, FEF25-75, and MEF50, adjusted for sex and anthropometric variables, were closely related to the decrease of pollutants concentration. Our results suggest that a decrease of air pollution may produce an improvement of lung function.     

Five cross-sectional studies of grain elevator workers.

Five cross-sectional studies were conducted on grain workers in all the terminal elevators in British Columbia, Canada, at 3-year intervals from 1976 to 1988. Civic workers were studied in the same manner as a referent group. The studies consisted of questionnaires, spirometry using the same spirometers, allergy skin tests, and measurement of dust concentration by personal sampling. Although the dust concentration in the elevators was reduced progressively over the years, grain workers had more respiratory symptoms and lower lung function compared with the civic workers in each of the five cross-sectional studies. Exposure to grain dust was associated with significant reduction in forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) but not in maximal midexpiratory flow rate or FEV1/FVC, suggesting reduction in volume which may be due to lesions in the lung parenchyma or in the small airways. Cigarette smoking was associated with significant reduction in FEV1, maximal midexpiratory flow rate, and FEV1/FVC due to airflow obstruction, but had no influence on FVC. Workers who took part in all five surveys tended to be a "healthier" selected group, but the grain workers still had lower lung function compared with the civic workers. This study confirmed previous findings that grain dust has adverse effects on the lungs. Cross-sectional study of the grain elevator workers proved to be a consistent and useful method to evaluate occupational health hazards.     

Notch1和PTEN在儿童支气管哮喘中的意义

目的探讨Notch1和磷酸酯酶和张力蛋白同源物基因(PTEN)在儿童支气管哮喘中的作用及意义。方法选取2015年1月-2018年1月河南某医院诊治的41例支气管哮喘患儿(观察组)及同期在该院进行健康体检的40例儿童(对照组)作为研究对象。检测研究对象肺功能指标[一秒用力呼气容积(FEV 1)、FEV 1/用力肺活量(FVC)、用力呼气中期流速(FEF25%~75%)、用力呼气50%肺活量的瞬间流速(FEF50%)、用力呼气75%肺活量的瞬间流速(FEF75%)、呼出气一氧化氮(FeNO)]、白细胞介素-6(IL-6)和嗜酸性粒细胞(Eos)水平,qRT-PCR检测Notch1和PTEN mRNA表达水平,将所得数据进行统计分析。结果观察组研究对象的FEV 1,FEV 1/FVC,FEF25%~75%,FEF50%及FEF75%分别为(1.38±0.65)L,(60.35±10.42)%,(3.15±1.23)L/s,(1.76±0.79)L/s及(0.78±0.54)L/s,均低于对照组的(2.47±0.53)L,(79.46±13.26)%,(4.09±1.57)L/s,(2.57±1.03)L/s及(1.25±0.38)L/s(均P<0.05)。观察组研究对象的FeNO为(17.35±11.53)ppb,高于对照组的(10.46±4.25)ppb(P<0.05)。观察组研究对象的Eos及IL-6分别为(0.36±0.13)×10^9/L及(0.73±0.17)ng/mL,均高于对照组的(0.16±0.11)×10^9/L及(0.38±0.14)ng/mL(均P<0.05)。观察组研究对象的Notch1 mRNA水平为1.52±0.13,明显高于对照组的0.87±0.09(P<0.05);观察组研究对象的PTEN mRNA水平为0.38±0.08,明显低于对照组的1.17±0.19(P<0.05)。相关性分析结果显示,Notch1 mRNA的表达水平与FEV 1,FEV 1/FVC,FEF25%~75%,FEF50%及FEF75%等指标呈现负相关(均P<0.05),与FeNO,IL-6和Eos等指标呈正相关(均P<0.05)。而PTEN mRNA的表达水平与FEV 1,FEV 1/FVC,FEF25%~75%,FEF50%及FEF75%等指标呈现正相关(均P<0.05),与FeNO,IL-6和Eos呈负相关(均P<0.05)。且Notch1 mRNA的表达与PTEN mRNA的表达呈现负相关(P<0.05)。结论哮喘患儿体内Notch1水平上调,Notch1可通过抑制PTEN表达及促进IL-6等炎症分子表达,诱导哮喘的发生和进展。     

南宁市空气污染水平不同的两区儿童肺功能及其影响因素的研究

目的 比较南宁市不同空气污染水平地区儿童肺功能的差异,探讨肺功能的影响相关因素。方法 按整群抽样方法,在南宁市青秀区和西乡塘区各选1所小学（A校和B校）3～4年级的儿童共537人作为研究对象,进行肺功能测试和问卷调查。结果 两区大气首要污染物都为PM2.5和PM10,青秀区A校周围大气中PM2.5、PM10、SO2、NO2年均浓度低于西乡塘区B校（P＜0.05）;控制年龄、身高、体重等因素后,青秀区A校女生FVC、FEV1.0、PEF、FEF25%～75%、FEF25%和FEF50%实测值均高于西乡塘区B校,A校男生FEV1.0实测值也高于B校,差异具有统计学意义（P＜0.05）;学校所在地区、房屋1年内购置大件家具、房屋3年内装修、房屋内饲养宠物和使用空气净化器是影响儿童肺功能的主要因素（P＜0.05）。结论 南宁市空气污染与儿童肺功能下降有关,且女生较男生对空气污染物更敏感;室内空气质量也是影响儿童肺功能的重要因素,空气净化器的使用对儿童肺功能有保护作用。     

初三年级1 240名学生的肺功能检测分析

目的 分析九江市初三学生肺通气功能的现状情况,为学生的素质健康发育提供指导依据。方法 选取2015年6月-2017年6月在九江市妇幼保健院院进行健康体检的1 240例初三学生为研究对象。对学生进行常规通气肺功能检测,包括肺活量(VC)、用力肺活量(FVC)、1 s用力呼气容积(FEV1)、峰值呼气流速(PEF)、用力呼出气量为25%肺活量时的平均流量(FEF25)、用力呼出气量为50%肺活量时的平均流量(FEF50)、用力呼出气量为75%肺活量时的平均流量(FEF75)、最大呼气中段流量(MMEF)和肺功能评分。比较不同年份、年龄、性别及体重指数(BMI)的学生的肺功能。结果 2015-2017年学生的肺功能各指标均不同程度降低(P<0.05)。随着年龄的增加,学生的肺功能各指标均有不同程度增高(P<0.05)。男生的肺功能普遍高于女生(P<0.05)。BMI为18.5~24.9 kg/m²学生的肺功能高于BMI＜18.5 kg/m²和BMI＞24.9 kg/m²的学生(P<0.05),BMI＜18.5 kg/m²的学生其FVC、FEV1和FEF75高于BMI＞24.9 kg/m²(P<0.05),两组其余肺功能相当(P>0.05)。结论 同年龄段学生的肺功能每年呈降低趋势,年龄越高,肺功能升高,男生的肺功能高于女生,超重或偏瘦学生的肺功能较低。初三学生应加强体育锻炼以增加其肺通气功能。     

Epidemiological-environmental study of diesel bus garage workers: acute effects of NO2 and respirable particulate on the respiratory system

Personal samples of nitrogen dioxide (NO2) and respirable particulate (RP) were collected over the shift on 232 workers in four diesel bus garages. Response was assessed by an acute respiratory questionnaire and before and after shift spirometry. Measures of exposure to NO2 and RP were associated with work-related symptoms of cough; itching, burning, or watering eyes; difficult or labored breathing; chest tightness; and wheeze. The prevalence of burning eyes, headaches, difficult or labored breathing, nausea, and wheeze experienced at work were higher in the diesel bus garage workers than in a comparison population of battery workers, while the prevalence of headaches was reduced. Mean reductions in forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), peak flow, and flows at 50 and 75% of FVC were not obviously different from zero. There was no detectable association of exposure to NO2 or respirable particulate and acute reductions in pulmonary function. Workers who often had respiratory work-related symptoms generally had a slightly greater mean acute reduction in FEV1 and FEF50 than did those who did not have these symptoms, but these differences were not statistically significant.     

Ventilatory function among metal workers in Singapore

The ventilatory function of 634 workers in small scale metal working industries was evaluated. Almost five percent (4.7%) of the workers were found to have FEV1.0/FVC ratio of less than 75%. Compared with the lung function of industrial workers reported by Zee, 10.9% were found to have low ventilatory function. Comparison of the ventilatory function obtained from the metal workers with those of occupational groups previously reported shows that the metal workers have lower FVC and FEV1.0 values. Mid and end expiratory flow rates were also measured. These measures have been shown to be very sensitive in detecting obstructions in small airways. It is recommended that future studies should be carried out to obtain ventilatory functions for the normal population. The values reported here of FEV25%-75% and FEF75%-85% would be useful for future investigations in forced expiratory flow rates.     

哮喘和咳嗽变异性哮喘儿童肺常规通气功能比较

目的 通过比较哮喘与咳嗽变异性哮喘儿童的肺常规通气功能,探讨其临床意义。 方法 选择2010年5-11月就诊于河北省儿童医院呼吸科门诊,确诊为哮喘或咳嗽变异性哮喘的患儿80例,分为:1)哮喘急性发作组(A组)33例,平均年龄(7.96±2.12)岁;2)哮喘缓解组(B组)27例,平均年龄(7.97±1.91)岁;3)咳嗽变异性哮喘组(C组)20例,平均年龄(8.03±2.18)岁;同时随机选择同期正常健康体检儿童30例,作为对照组(D组),平均年龄(8.58±2.11)岁。测定用力肺活量(FVC)、一秒钟用力呼气容积(FEV1)、最大呼气峰流速(PEF)、用力呼气25%流速(FEF25)、用力呼气50%流速(FEF50)、用力呼气75%流速(FEF75)、最大呼气中期流速(MMEF75/25)等7项指标。 结果 A、B、C三组患儿各项肺功能指标均低于D组儿童(B、C组除外PEF、FEF50、FEF75),且A组各项肺功能指标均明显低于B和C组; 但B、C两组患儿差异无统计学意义。 结论 肺常规通气功能检测可以评价哮喘与咳嗽变异性哮喘患儿的气道阻塞程度,对于诊断及病情评估有重要意义。     

基于广义线性混合模型分析可吸入颗粒物对儿童肺功能的影响

目的采用广义线性混合模型,探讨可吸入颗粒物(PM)对儿童肺功能的影响。方法 2005-2006年,采用多阶段随机抽样的方法,招募6~8岁儿童1 000名,采用问卷调查的形式,收集人口和社会经济学特征、生活方式和病史的信息,并每年进行1次体检,直至研究对象年满17岁;采用肺功能测定仪检测每名儿童的1秒用力呼气量(FEV1)、用力肺活量(FVC)和峰值呼气流量(PEF),每名受试者进行3次肺功能测试,取平均值。采用广义线性混合模型探讨PM对儿童肺功能的影响。结果截至2017年,共有912名研究对象完成随访,随访率91.2%。广义线性混合模型分析表明,PM2.5每增加5μg/m^3,FVC下降1.26%,FEV1下降1.51%,FEF下降1.39%。PM10每增加5μg/m^3,FVC下降1.35%,FEV1下降1.63%,FEF下降1.43%。亚组分析表明,在暴露于二手烟的儿童中,可吸入颗粒物对肺功能影响更加显著(P值均<0.001)。结论 PM浓度与儿童肺功能指标呈负相关,PM浓度增加可导致儿童肺功能降低。     

Respiratory symptoms and ventilatory capacity in soy bean workers

Respiratory function was studied in a group of 29 soy workers exposed to soy bean dust produced after extraction of soy oil. The prevalence of all chronic respiratory symptoms was consistently higher in exposed than in control workers, although the differences were not statistically significant. During the Monday work shift there was a significant mean acute across-shift decrease in maximum expiratory flow rates at 50% and 25% vital capacity (FEF50: -6.4%; FEF25: -12.4%). Changes in vital capacity (FVC: -3.6%) and 1-sec forced expiratory volume (FEV1: -2.7%) were smaller, but still statistically significant. There were also statistically significant acute reductions in all ventilatory capacity parameters over the work shift on the following Friday, although the changes were in general smaller than on Monday (except for FEV1). An analysis of Monday preshift values of ventilatory capacity in soy bean workers suggests that exposure to soy bean dust may lead to chronic respiratory impairment in some workers.     

慢性咳嗽患者小气道功能的改变及其临床价值

目的 初步评价肺功能检测中反映小气道功能的指标对慢性咳嗽患者鉴别诊断的临床价值.方法 对109例慢性咳嗽患者进行常规肺功能检测和支气管激发试验,观察支气管激发试验阳性患者与阴性患者小气道功能指标的差异,以及小气道功能异常与正常患者肺功能指标差异和支气管激发试验的阳性率.结果 109例患者中支气管激发试验阳性60例,阴性49例.支气管激发试验阳性患者峰值呼气流速、最大呼气中期流速75/25、呼气中段流速(FEF)25、FEF50、FEF75较阴性患者低,差异有统计学意义(P<0.05),肺活量、用力肺活量、第1秒用力呼气容积、第1秒用力呼气容积占用力肺活量百分比两者比较差异无统计学意义.109例患者中有48例提示小气道功能异常,其中39例支气管激发试验阳性,占81.2%;而小气道功能正常的6l例患者中,有21例支气管激发试验阳性,占34.4%,两者阳性率比较差异有统计学意义(P<0.01).结论 肺功能中反映小气道功能的指标能预测气道高反应性,对于大量不能开展支气管激发试验的基层医院,有助于发现早期咳嗽变异型哮喘患者,尤其对于合并小气道病变的年轻患者更重要.     

Respiratory findings in spice factory workers

The respiratory consequences of working in the spice industry were studied in 92 female spice factory workers (mean age, 36 yr; mean exposure, 12 yr). A control group of 104 female workers employed in a nondusty industry was also studied. The prevalence of chronic respiratory symptoms was significantly higher in the exposed than in the control group. In particular, the prevalence of dyspnea (57.6%), chronic cough (22.8%), chronic phlegm and chronic bronchitis (19.6%), nasal catarrh (37.0%), and sinusitis (22.2%) was high when compared to controls (p less than .01). Among spice factory workers, a high prevalence of acute symptoms during the workshift was recorded. Acute reductions in lung function were statistically significant over the workshift for forced vital capacity (FVC), -2.0%; forced expiratory volume in one second (FEV1.0), -3.0%; and for maximum expiratory flow rates at 50% (FEF50), -8.3% and at 25% (FEF25), -15.2% measured on maximum expiratory flow-volume (MEFV) curves. No difference was found in across-shift ventilatory function in workers with or without chronic respiratory symptoms, except for FEF25 (with symptoms, 16.7%; without symptoms, 9.6%). Preshift administration of 40 mg of disodium cromoglycate (DSC) inhaled 15 min before the workshift significantly diminished acute reductions in FEF50 and FEF25 in exposed workers. Monday preshift FEF50 and FEF25 in exposed workers were significantly lower than in control workers (p less than .01), which suggests an early irreversible component to this illness.     

Spirometric prediction equations for male Italians 7–18 years of age

The purpose of this study was to develop spirometric predictive equations (SPE) for forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and maximum midexpiratory flow (MMF25-75) derived from a large sample of healthy italian boys and male adolescents. We used the univariate and multiple linear regression models and considered as independent variables age and the following anthropometric measurements: height, weight, chest circumference. The predictive power of multivariate models was slightly higher than that of the univariate model using height as independent variable for FVC, FEV 1 and MMF25-75.Abbreviations SPE Spirometric predictive equation - FVC Forced vital capacity - FEV1 Forced expiratory volume in one second - MMF25-75 Maximum midexpiratory flow - PPV Percent predicted value (actual value/predicted value)%     

Changes in lung function of granite crushers exposed to moderately high silica concentrations: a 12 year follow up.

45 granite crushers and 45 age and smoking matched referents underwent pulmonary function tests in 1976 and 1988. On average, the granite crushers at follow up had worked for 22 years, were 52 (range 36-78) years old, and had inhaled a cumulated amount of 7 mg of silica in the respirable dust fraction. Between 1976 and 1988 the average concentration of respirable quartz in air was 0.16 mg/m3 (threshold limit value (TLV) = 0.10 mg/m3). In 1988 the granite crushers had somewhat lower forced expiratory flows (forced expiratory volume in one second/vital capacity (FEV1/VC) -4.5% and forced midexpiratory flow FEF50 -15%) compared with the referents and a more uneven ventilation distribution (17% higher slope of phase III in the nitrogen single breath curve). Five smoking granite crushers, but none of the referents, had an FEV1 < 80% of the predicted. During the 12 year interval the granite crushers had--compared with the matched referents--a greater decrease in FEV1 (-4.6%), FEV1/VC (-5.4%), maximal expiratory flow, (-8%) and FEF50 (-14%), and a larger increase in phase III and static compliance (p < 0.02 in all variables). The functional changes suggest the presence of airways obstruction and increased compliance of the lungs. Exposure to silica at concentrations of about twice the present TLV was thus associated with airways obstruction and loss of elastic recoil rather than fibrosis and a restrictive function loss as seen in silicosis. The changes were on average small, but in some tobacco smokers more pronounced changes were found.