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Archives of Environmental Health: An International Journal Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/vzeh20
Occult Exposure to Asbestos in Steel Workers Revealed by Bronchoalveolar Lavage a
a
a
Jean-Louis Corhay M.D. , Jean-Paul Delavignette M.D. , Thierry Bury M.D. , Pierre Sainta
Remy M.D. & Maurice-Francois Radermecker M.D.
a
a
Department of Pneumology , CHU , Liege, Belgium Published online: 03 Aug 2010.
To cite this article: Jean-Louis Corhay M.D. , Jean-Paul Delavignette M.D. , Thierry Bury M.D. , Pierre Saint-Remy M.D. & Maurice-Francois Radermecker M.D. (1990) Occult Exposure to Asbestos in Steel Workers Revealed by Bronchoalveolar Lavage, Archives of Environmental Health: An International Journal, 45:5, 278-282, DOI: 10.1080/00039896.1990.10118746 To link to this article: http://dx.doi.org/10.1080/00039896.1990.10118746
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions
Occult Exposure to Asbestos in Steel Workers Revealed by
Downloaded by [Monash University Library] at 19:57 06 March 2015
Bronchoalveolar Lavage
JEAN-LOUIS CORHAY, M.D. JEAN-PAUL DELAVICNETTE, M.D. THIERRY BURY, M.D. PIERRE SAINT-REMY, M.D. MAURICE-FRANCOIS RADERMECKER, M.D. Department of Pneumology CHU Liege, Belgium
ABSTRACT. To investigate the asbestos burden in a steelplant environment, we counted asbestos bodies (ABs) in the bronchoalveolar lavage fluid (BALF) of 65 steel workers who had retired during the previous 5 y. They had worked for at least 15 y in the same area of the plant (coke oven or blast furnace) as maintenance or production workers. On the basis of occupational anamnesis, 28 had occasional past professional exposure to asbestos; the remaining 37 workers denied any contact with asbestos. A total of 54 white-collar workers who had no occupational exposure to asbestos were included in the study as controls. An increased prevalence and concentration of ABs was found in the BALF of steel workers. Electron microscopy and EDAX analysis of AB from steel workers revealed that the core fibers were mainly amphiboles. More ABs were found in the BALF of maintenance workers than in production workers. However, the BALF from steel workers who denied any contact with asbestos revealed an increased AB burden v. controls. This demonstrates that steel workers may be subject to an occult exposure to amphiboles in the steelplant environment.
STEEL WORKERS are exposed to many pollutants. These workers have a high risk of developing chronic bronchi ti^,'-^ pneumo~oniosis,~ metal fume fever,5 and lung c a n ~ e r . ~Many - ~ carcinogens, e.g., asbestos, polycyclic aromatic hydrocarbons, nickel, chromium, etc., can be inhaled in a steel plant. However, the extent to which steel workers are exposed to such carcinogens i s still debated. Churg et a1.l0 demonstrated that lung sample digests from autopsied steel workers, including manual laborers who worked in the mill, contained more asbestos bodies (ABs) than those of white-collar workers. Bronchoalveolar lavage (BAL) provides an easy and relatively noninvasive technique that enables
collection of intra-alveolar ABs. It i s an appropriate procedure for documenting exposure to asbest 0s. 11-14
This study investigates possible occult exposure to amphiboles in a steel plant environment. Asbestos bodies were counted in the bronchoalveolar lavage fluid (BALF) of steel workers who retired during the past 5 y. The steel workers were employed for a period of at least 15 y in the same working area, i.e., blast furnace or coke oven.
Subjects and methods Subjects. A total of 472 steel workers who had retired during the past 5 y (Cockerill-Sambre, Liege, Archives of Environmental Health
Downloaded by [Monash University Library] at 19:57 06 March 2015
Belgium) were invited, by letter, to participate in this study. They were asked to undergo a clinical examination, chest x-ray, lung function tests (spirometry and carbon monoxide diffusing capacity) and fiberoptic bronchoscopy with bronchoalveolar lavage (BAL). One hundred and twenty-one (26%)agreed to participate. Only workers who had been employed for at least 15 y in the same working area (blast furnace or coke oven) of the steel plant were selected. They were grouped according to type of job (maintenance or production) and work area. Chest x-ray, medical examination, pulmonary function tests, and bronchoalveolar lavage were conducted. Fifty-four white-collar workers (mean age 51; 2 t 12.3 y) who had no exposure to asbestos, as evidenced by anamnesis, and who were free of asbestos-related disease served as controls. They included 15 healthy volunteers (mean age 50 5 10.8 y), of whom 7 were smokers (26 pack-year) and 8 were nonsmokers; and 39 in- or outpatients (mean age 56.4 ? 12.5 y), of whom 18 were smokers (20 pack-year) and 21 were nonsmokers. The in- or outpatients were being treated for chronic obstructive pulmonary disease, sarcoidosis, asthma, or extrinsic alveolitis. The group of healthy volunteers were also studied for the BALF cytology. Pulmonary function tests. Vital capacity (VC), forced expiratory volume in 1 sec (FEV,,,), total lung capacity (TLC), functional residual capacity (FRC) and residual volume were determined using a watersealed spirometer (Jaeger Spirojunior). Spirometric measurements were performed with the subject seated and wearing a nose clip. Carbon monoxide diffusing capacity (DL,,) was measured by the singlebreath method and was corrected for alveolar volume (Morgan transfert test). Results were expressed as a percentage of the predicted values (1983 ECSC criteria) .15 Bronchoalveolar lavage. Fiberoptic bronchoscopy was done under local anesthesia in accordance with standardized technique.16-'8 Sterile saline (200-250 ml) at 37 "C was injected by 50-ml bolus into a subsegmental area of the median lobe. The BALF was recuperated by mild aspiration. The BALF yield was 50-90% of the volume injected and was processed immed iat eIy. BALF analysis. The BALF sample was centrifuged at 400 g for 10 min, and pelleted cells were resuspended in 1 ml of saline solution. Cells were counted in a Thoma cell. A cell smear was stained with Diff-Quick reagent (Harleco), and a differential count was completed by examining 300 cells (by the same observer). To count ABs, a 20-ml BALF aliquot was treated with an equal volume of filtered sodium hypochlorite and filtered through a cellulose ester filter (Millipore, porosity 0.45 pm) and dried at 60" C. The filter was mounted on a glass slide with a 1 : l mixture of amyl and ethylacetate and examined by light microscopy (200 x m a g n i f i c a t i ~ n ) . ~ l JOnly * , ~ ~ferruginous bodies that developed on a thin, straight, transparent central core, with regular or regularly segSeptembedOctober 1990 [Vol. 45 (No. 5)]
mented, yellow to brown ferro-protein coating were co sidered as All ABs present on the whole fi r were counted, and results were expressed as a number of ABs/ml of BALF. The detection limit of the technique is 0.05 ABs/ml BALF, i.e., 1 AB/20 ml BALF). To determine the type of asbestos fiber, some of the ABs found in the BA1.F of 10 steel workers were examined by analytical electron microscopy (scanning or transmission) coupled with the EDAX (Energy Dispersive x-ray analysis) system (Research Unit on the Toxicity of Mineral Particles, Hospital Erasme, Chest Department Brussels, Belgium). Statistical analysis. Results are given as means 5 standard deviations (SD). The chi-square test and unpaired Student's t test were used. A p value < .05 was considered significant. Results Subjects. Sixty-five steel workers (mean age 54.6 t 8 y) were studied, of whom 36 were smokers (mean
cigarette consumption 25 pack-year) and 29 were nonsmokers. The mean number of years spent at work was 26 t 9. Qualified maintenance workers and unqualified workers numbered 22 and 43, respectively; unqualified employees worked exclusively in the production of coke and steel. Production workers had worked in either the blast furnace area ( n = 25) or coke oven area ( n = 18). Twentytwo maintenance workers and 6 unqualified production workers who were admitted during anamnesis (by the same doctor: JLC) experienced occasional work-related exposure to asbestos. Both groups were similar with respect to age, mean number of years spent at work, and smoking habits (Tables 1 and 2). Clinical data. Twelve of the 65 steel workers reported chronic cough and sputum. On the basis of American Thoracic Society criteria," these workers were deemed as suffering from chronic obstructive pulmonary disease (COPD). In 4 workers, wheezing was noted upon clinical examination. All other workers reported no pulmonary symptoms and had a normal clinical examination. Lung function data of COPD and non-COPD workers are shown in Table 3. As expected, mean FEV,,,, VC, and FEVl,pC were significantly lower, and RV was significantly higher in the COPD steel workers v. asymptomatic steel workers. The DLco was decreased in workers with COPD, but the difference was not significant. With the exception of 2 asymptomatic maintenance workers who had experienced work-related exposure to asbestos, chest x-rays were normal for the 65 steel workers. In these 2 workers, chest x-ray and CT scan disclosed several partially calcified pleural plaques. Subsequently, we found that their BALF contained 3 and 16 AB/mI, respectively. Fiberoptic bronchoscopy revealed no abnormality in the 65 steel workers. The bronchoalveolar lavage was well tolerated. Only one worker reported a mild and transient fever during the 10 h that followed lavage. 279
Table 1 .-Characteristics of 65 Retired Steel Workers According to JobCategory (i.e., Maintenance or Production) and Working Area (Blast Furnace or Coke Oven) of Production Workers Production Maintenance
Blast Furnace
Coke oven
22 53.6 -c 11.4
25 55.4 2 6
18 55.7 2 3.5
Total
1
Downloaded by [Monash University Library] at 19:57 06 March 2015
Number Age ( y ) Smokers/ nonsmokers Smoking history (pack-year) Number of years spent at work
12110
14/11
22.0 IT 7.3
24.2 2 5
29.6 -t 7.5
26.5 2 6
24.9 It 9.5
27.2 % 7.8
23.0 2 6.0
25.8 2 7.4
Table 2.-Characteristics of 65 Retired Steel Workers Evaluated by Occupational Anamnesis
Number Age (y) Smokers/ nonsmokers Smoking history (pack-years) Mean duration at work (y)
Table 3.-Lung Workers
Exposed steel workers
Nonexposed steel workers
28 56.4 % 3.0
37 55.0 2 6.4
15113
19118
24.0 2 3.2
26.0 2 5.4
28.0 -c 7.0
26.1 26.7
Function Tests in 65 Pre-retired Steel
Age (y) Smokers (%) VC (% Pred.) FEV, J% Pred.) RV (% Pred.) TLC (% Pred.) FRCHe (% Pred.) FEV, ,NC (% Pred.) DLco (% Pred.)
Non-COPD ( n = 53) (Mean 2 SD)
COPD (n = 12) (Mean 2 SD)
55 2 2 55 1 0 0 . 0 113.0 ~ 96.2214.7 103.7 235.5 101.62 15.8 101 2 20.0 73.32 6.1 99.7? 22.8
56 -c 3 50 86.5 2 11.7' 68.2 -C 13.2t 130.0 2 33.7$ 102.4216.1 105.0 +. 28.2 60.22 7.9t 91.5 -C 30.2
.o
* p 1.01. tp < ,001. *p < .05.
BALF examination. The number of cells/ml BALF and the differential cell count were not different in steel workers v. nonexposed healthy volunteers, but cell yields in both groups were significantly higher in smokers than in nonsmokers (Table 4). 280
43 55.5 IT 5
1018
24119
Asbestos bodies (> 0.05/mI) were found (Fig. 1) in the BALF of 38 steel workers (58.5%)and in only 6% of controls ( p < .01). The percentage of BALF that contained more than 1 AB/ml was also higher in steel workers (29.2%) than in nonexposed subjects (2%) ( p < .01). Sixty-three AB cores from the BALF of 10 steel workers were analyzed by analytical electron microscopy coupled to EDAX. All were asbestos fibers, composed mainly of amphiboles identified as crocidolite ( n = 321, amosite ( n = 201, background amositekrocidolite ( n = 8 ) , tremolite ( n = I ) , and chrysotile ( n = 2). As expected, we found a significantly increased AB burden in the BALF of steel workers who admitted occasional asbestos exposure v. controls. The percentage of BALF containing more than 1 AB/ ml was also significantly higher in exposed than in nonexposed steel workers ( p < .05) (Fig. 2). Moreover, when comparing the workers who had denied any exposure to asbestos with controls, we found a significantly higher percentage of positive BALF and AB concentration in the former ( p < .01). Smoking habits and the presence of COPD did not influence AB counts in the BALF of steel workers. As expected, maintenance workers had significantly higher AB counts than unqualified production workers ( p < .05) (Fig. 3). Twenty-five unqualified blast furnace workers and 18 unqualified coke oven workers were compared with respect to their BALF AB content. Asbestos bodies were found (Fig. 4) in 14 blast furnace workers (6 had > 1 AB/ml) and in only 6 coke oven workers (all < 1 AB/ml). This difference, however, is not statistically significant ( p = .07). We also had the opportunity to obtain BALF samples from repeated lavages performed on 7 of the steel workers. Time intervals between successive BAL ranged from 7 to 35 mo (mean 25.1 +- 11). Except for one result (i.e., 2.2 AB/mI to 0.15 AB/ml), results were found to stay in the same groups (0, < I , 1-10, and > 10 AB/mI BALF). Within a 5-y limit, the asbestos body count was not affected by time since cessation of exposure. BALF containing more than 10 ABs/ml had a Archives of Environmental Health
Table 4.-Cytology of Bronchoalveolar lavage Fluid From 15 Healthy White-collar Workers and 65 Steel Workers Who Had Retired within the Previous 5 y Retired steel workers (Mean 2 SD)
Healthy white-collar workers (Mean 2 SD)
Cells/ml BALF ( X 104) Macrophages(%) Lymphocytes(%)
20.0213.0
6.1 4 3.4
p
Archives of Environmental Health: An International Journal Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/vzeh20
Occult Exposure to Asbestos in Steel Workers Revealed by Bronchoalveolar Lavage a
a
a
Jean-Louis Corhay M.D. , Jean-Paul Delavignette M.D. , Thierry Bury M.D. , Pierre Sainta
Remy M.D. & Maurice-Francois Radermecker M.D.
a
a
Department of Pneumology , CHU , Liege, Belgium Published online: 03 Aug 2010.
To cite this article: Jean-Louis Corhay M.D. , Jean-Paul Delavignette M.D. , Thierry Bury M.D. , Pierre Saint-Remy M.D. & Maurice-Francois Radermecker M.D. (1990) Occult Exposure to Asbestos in Steel Workers Revealed by Bronchoalveolar Lavage, Archives of Environmental Health: An International Journal, 45:5, 278-282, DOI: 10.1080/00039896.1990.10118746 To link to this article: http://dx.doi.org/10.1080/00039896.1990.10118746
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions
Occult Exposure to Asbestos in Steel Workers Revealed by
Downloaded by [Monash University Library] at 19:57 06 March 2015
Bronchoalveolar Lavage
JEAN-LOUIS CORHAY, M.D. JEAN-PAUL DELAVICNETTE, M.D. THIERRY BURY, M.D. PIERRE SAINT-REMY, M.D. MAURICE-FRANCOIS RADERMECKER, M.D. Department of Pneumology CHU Liege, Belgium
ABSTRACT. To investigate the asbestos burden in a steelplant environment, we counted asbestos bodies (ABs) in the bronchoalveolar lavage fluid (BALF) of 65 steel workers who had retired during the previous 5 y. They had worked for at least 15 y in the same area of the plant (coke oven or blast furnace) as maintenance or production workers. On the basis of occupational anamnesis, 28 had occasional past professional exposure to asbestos; the remaining 37 workers denied any contact with asbestos. A total of 54 white-collar workers who had no occupational exposure to asbestos were included in the study as controls. An increased prevalence and concentration of ABs was found in the BALF of steel workers. Electron microscopy and EDAX analysis of AB from steel workers revealed that the core fibers were mainly amphiboles. More ABs were found in the BALF of maintenance workers than in production workers. However, the BALF from steel workers who denied any contact with asbestos revealed an increased AB burden v. controls. This demonstrates that steel workers may be subject to an occult exposure to amphiboles in the steelplant environment.
STEEL WORKERS are exposed to many pollutants. These workers have a high risk of developing chronic bronchi ti^,'-^ pneumo~oniosis,~ metal fume fever,5 and lung c a n ~ e r . ~Many - ~ carcinogens, e.g., asbestos, polycyclic aromatic hydrocarbons, nickel, chromium, etc., can be inhaled in a steel plant. However, the extent to which steel workers are exposed to such carcinogens i s still debated. Churg et a1.l0 demonstrated that lung sample digests from autopsied steel workers, including manual laborers who worked in the mill, contained more asbestos bodies (ABs) than those of white-collar workers. Bronchoalveolar lavage (BAL) provides an easy and relatively noninvasive technique that enables
collection of intra-alveolar ABs. It i s an appropriate procedure for documenting exposure to asbest 0s. 11-14
This study investigates possible occult exposure to amphiboles in a steel plant environment. Asbestos bodies were counted in the bronchoalveolar lavage fluid (BALF) of steel workers who retired during the past 5 y. The steel workers were employed for a period of at least 15 y in the same working area, i.e., blast furnace or coke oven.
Subjects and methods Subjects. A total of 472 steel workers who had retired during the past 5 y (Cockerill-Sambre, Liege, Archives of Environmental Health
Downloaded by [Monash University Library] at 19:57 06 March 2015
Belgium) were invited, by letter, to participate in this study. They were asked to undergo a clinical examination, chest x-ray, lung function tests (spirometry and carbon monoxide diffusing capacity) and fiberoptic bronchoscopy with bronchoalveolar lavage (BAL). One hundred and twenty-one (26%)agreed to participate. Only workers who had been employed for at least 15 y in the same working area (blast furnace or coke oven) of the steel plant were selected. They were grouped according to type of job (maintenance or production) and work area. Chest x-ray, medical examination, pulmonary function tests, and bronchoalveolar lavage were conducted. Fifty-four white-collar workers (mean age 51; 2 t 12.3 y) who had no exposure to asbestos, as evidenced by anamnesis, and who were free of asbestos-related disease served as controls. They included 15 healthy volunteers (mean age 50 5 10.8 y), of whom 7 were smokers (26 pack-year) and 8 were nonsmokers; and 39 in- or outpatients (mean age 56.4 ? 12.5 y), of whom 18 were smokers (20 pack-year) and 21 were nonsmokers. The in- or outpatients were being treated for chronic obstructive pulmonary disease, sarcoidosis, asthma, or extrinsic alveolitis. The group of healthy volunteers were also studied for the BALF cytology. Pulmonary function tests. Vital capacity (VC), forced expiratory volume in 1 sec (FEV,,,), total lung capacity (TLC), functional residual capacity (FRC) and residual volume were determined using a watersealed spirometer (Jaeger Spirojunior). Spirometric measurements were performed with the subject seated and wearing a nose clip. Carbon monoxide diffusing capacity (DL,,) was measured by the singlebreath method and was corrected for alveolar volume (Morgan transfert test). Results were expressed as a percentage of the predicted values (1983 ECSC criteria) .15 Bronchoalveolar lavage. Fiberoptic bronchoscopy was done under local anesthesia in accordance with standardized technique.16-'8 Sterile saline (200-250 ml) at 37 "C was injected by 50-ml bolus into a subsegmental area of the median lobe. The BALF was recuperated by mild aspiration. The BALF yield was 50-90% of the volume injected and was processed immed iat eIy. BALF analysis. The BALF sample was centrifuged at 400 g for 10 min, and pelleted cells were resuspended in 1 ml of saline solution. Cells were counted in a Thoma cell. A cell smear was stained with Diff-Quick reagent (Harleco), and a differential count was completed by examining 300 cells (by the same observer). To count ABs, a 20-ml BALF aliquot was treated with an equal volume of filtered sodium hypochlorite and filtered through a cellulose ester filter (Millipore, porosity 0.45 pm) and dried at 60" C. The filter was mounted on a glass slide with a 1 : l mixture of amyl and ethylacetate and examined by light microscopy (200 x m a g n i f i c a t i ~ n ) . ~ l JOnly * , ~ ~ferruginous bodies that developed on a thin, straight, transparent central core, with regular or regularly segSeptembedOctober 1990 [Vol. 45 (No. 5)]
mented, yellow to brown ferro-protein coating were co sidered as All ABs present on the whole fi r were counted, and results were expressed as a number of ABs/ml of BALF. The detection limit of the technique is 0.05 ABs/ml BALF, i.e., 1 AB/20 ml BALF). To determine the type of asbestos fiber, some of the ABs found in the BA1.F of 10 steel workers were examined by analytical electron microscopy (scanning or transmission) coupled with the EDAX (Energy Dispersive x-ray analysis) system (Research Unit on the Toxicity of Mineral Particles, Hospital Erasme, Chest Department Brussels, Belgium). Statistical analysis. Results are given as means 5 standard deviations (SD). The chi-square test and unpaired Student's t test were used. A p value < .05 was considered significant. Results Subjects. Sixty-five steel workers (mean age 54.6 t 8 y) were studied, of whom 36 were smokers (mean
cigarette consumption 25 pack-year) and 29 were nonsmokers. The mean number of years spent at work was 26 t 9. Qualified maintenance workers and unqualified workers numbered 22 and 43, respectively; unqualified employees worked exclusively in the production of coke and steel. Production workers had worked in either the blast furnace area ( n = 25) or coke oven area ( n = 18). Twentytwo maintenance workers and 6 unqualified production workers who were admitted during anamnesis (by the same doctor: JLC) experienced occasional work-related exposure to asbestos. Both groups were similar with respect to age, mean number of years spent at work, and smoking habits (Tables 1 and 2). Clinical data. Twelve of the 65 steel workers reported chronic cough and sputum. On the basis of American Thoracic Society criteria," these workers were deemed as suffering from chronic obstructive pulmonary disease (COPD). In 4 workers, wheezing was noted upon clinical examination. All other workers reported no pulmonary symptoms and had a normal clinical examination. Lung function data of COPD and non-COPD workers are shown in Table 3. As expected, mean FEV,,,, VC, and FEVl,pC were significantly lower, and RV was significantly higher in the COPD steel workers v. asymptomatic steel workers. The DLco was decreased in workers with COPD, but the difference was not significant. With the exception of 2 asymptomatic maintenance workers who had experienced work-related exposure to asbestos, chest x-rays were normal for the 65 steel workers. In these 2 workers, chest x-ray and CT scan disclosed several partially calcified pleural plaques. Subsequently, we found that their BALF contained 3 and 16 AB/mI, respectively. Fiberoptic bronchoscopy revealed no abnormality in the 65 steel workers. The bronchoalveolar lavage was well tolerated. Only one worker reported a mild and transient fever during the 10 h that followed lavage. 279
Table 1 .-Characteristics of 65 Retired Steel Workers According to JobCategory (i.e., Maintenance or Production) and Working Area (Blast Furnace or Coke Oven) of Production Workers Production Maintenance
Blast Furnace
Coke oven
22 53.6 -c 11.4
25 55.4 2 6
18 55.7 2 3.5
Total
1
Downloaded by [Monash University Library] at 19:57 06 March 2015
Number Age ( y ) Smokers/ nonsmokers Smoking history (pack-year) Number of years spent at work
12110
14/11
22.0 IT 7.3
24.2 2 5
29.6 -t 7.5
26.5 2 6
24.9 It 9.5
27.2 % 7.8
23.0 2 6.0
25.8 2 7.4
Table 2.-Characteristics of 65 Retired Steel Workers Evaluated by Occupational Anamnesis
Number Age (y) Smokers/ nonsmokers Smoking history (pack-years) Mean duration at work (y)
Table 3.-Lung Workers
Exposed steel workers
Nonexposed steel workers
28 56.4 % 3.0
37 55.0 2 6.4
15113
19118
24.0 2 3.2
26.0 2 5.4
28.0 -c 7.0
26.1 26.7
Function Tests in 65 Pre-retired Steel
Age (y) Smokers (%) VC (% Pred.) FEV, J% Pred.) RV (% Pred.) TLC (% Pred.) FRCHe (% Pred.) FEV, ,NC (% Pred.) DLco (% Pred.)
Non-COPD ( n = 53) (Mean 2 SD)
COPD (n = 12) (Mean 2 SD)
55 2 2 55 1 0 0 . 0 113.0 ~ 96.2214.7 103.7 235.5 101.62 15.8 101 2 20.0 73.32 6.1 99.7? 22.8
56 -c 3 50 86.5 2 11.7' 68.2 -C 13.2t 130.0 2 33.7$ 102.4216.1 105.0 +. 28.2 60.22 7.9t 91.5 -C 30.2
.o
* p 1.01. tp < ,001. *p < .05.
BALF examination. The number of cells/ml BALF and the differential cell count were not different in steel workers v. nonexposed healthy volunteers, but cell yields in both groups were significantly higher in smokers than in nonsmokers (Table 4). 280
43 55.5 IT 5
1018
24119
Asbestos bodies (> 0.05/mI) were found (Fig. 1) in the BALF of 38 steel workers (58.5%)and in only 6% of controls ( p < .01). The percentage of BALF that contained more than 1 AB/ml was also higher in steel workers (29.2%) than in nonexposed subjects (2%) ( p < .01). Sixty-three AB cores from the BALF of 10 steel workers were analyzed by analytical electron microscopy coupled to EDAX. All were asbestos fibers, composed mainly of amphiboles identified as crocidolite ( n = 321, amosite ( n = 201, background amositekrocidolite ( n = 8 ) , tremolite ( n = I ) , and chrysotile ( n = 2). As expected, we found a significantly increased AB burden in the BALF of steel workers who admitted occasional asbestos exposure v. controls. The percentage of BALF containing more than 1 AB/ ml was also significantly higher in exposed than in nonexposed steel workers ( p < .05) (Fig. 2). Moreover, when comparing the workers who had denied any exposure to asbestos with controls, we found a significantly higher percentage of positive BALF and AB concentration in the former ( p < .01). Smoking habits and the presence of COPD did not influence AB counts in the BALF of steel workers. As expected, maintenance workers had significantly higher AB counts than unqualified production workers ( p < .05) (Fig. 3). Twenty-five unqualified blast furnace workers and 18 unqualified coke oven workers were compared with respect to their BALF AB content. Asbestos bodies were found (Fig. 4) in 14 blast furnace workers (6 had > 1 AB/ml) and in only 6 coke oven workers (all < 1 AB/ml). This difference, however, is not statistically significant ( p = .07). We also had the opportunity to obtain BALF samples from repeated lavages performed on 7 of the steel workers. Time intervals between successive BAL ranged from 7 to 35 mo (mean 25.1 +- 11). Except for one result (i.e., 2.2 AB/mI to 0.15 AB/ml), results were found to stay in the same groups (0, < I , 1-10, and > 10 AB/mI BALF). Within a 5-y limit, the asbestos body count was not affected by time since cessation of exposure. BALF containing more than 10 ABs/ml had a Archives of Environmental Health
Table 4.-Cytology of Bronchoalveolar lavage Fluid From 15 Healthy White-collar Workers and 65 Steel Workers Who Had Retired within the Previous 5 y Retired steel workers (Mean 2 SD)
Healthy white-collar workers (Mean 2 SD)
Cells/ml BALF ( X 104) Macrophages(%) Lymphocytes(%)
20.0213.0
6.1 4 3.4
p
