journal article
Download Only Collection
Home
doi: 10.1136/oem.44.9.580pmid: 3663525
Mortality among workers in the Finnish pulp and paper industry was evaluated in a retrospective cohort study of 3520 workers who had been employed continuously for at least one year between 1945 and 1961. Six subcohorts were formed according to six work areas: sulphite, sulphate, paper, and board mills, maintenance department, and power plant. National mortality rates were used for comparison. The mortality of a cohort of 1290 sawmill workers was also studied in order to have a socially, geographically, and occupationally similar group without the exposures typical of the pulp and paper industry for comparison. Smoking habits were surveyed. Mortality was followed up until 31 December 1981. Overall mortality for the entire cohort did not differ from that expected (1044 obs, 1029.4 exp, SMR 101), but there was an excess of deaths from diseases of the circulatory system among the men (489 obs, 404.9 exp, SMR 121). This was due to the excess of deaths from ischaemic heart disease found among the men at the sulphite, sulphate, and paper mills, maintenance department, and power plant, but not at the sawmill. The existing smoking data did not explain this finding and it may therefore be associated with occupational exposures.
Finkelstein, M; Liss, G M; Krammer, F; Kusiak, R A
doi: 10.1136/oem.44.9.588pmid: 2959310
The mortality experience of 1190 miners and 289 surface industry workers receiving workers' compensation awards for silicosis in Ontario since 1940 has been studied up to mid-1985. Both groups were found to have a significantly increased mortality from lung cancer (miners' SMR: 230; surface workers' SMR: 302) and stomach cancer (miners' SMR: 188; surface workers' SMR: 366). Adjustment for smoking and country of origin did not explain the excesses observed. The lung cancer findings are consistent with observations from silicosis registries in Europe. Possible explanatory factors are discussed.
doi: 10.1136/oem.44.9.595pmid: 3663526
A cohort of 537 workers employed for less than one year between 1900 and 1964 in the Geneva perfumery industry was followed up from entry to the end of 1983. During the period of study, 251 workers died and 41 (8%) were lost to follow up. The standardised mortality ratio (SMR) was significantly above 100 for all causes (SMR = 120), all cancers (SMR = 127), lung cancer (SMR = 186), and violent death (SMR = 179). The highest SMR from all causes was associated with the shortest period of employment (less than two months) and it decreased significantly with longer duration. Such mortality excesses had not been recorded among the 1168 workers of the same industry employed one year or more, previously studied in similar fashion. Interviews among a random sample of 52 workers employed for less than two months seem to indicate that the prevalence of smoking, exposures to asbestos, and occupational accidents in other hazardous industries were higher for these workers than for the reference population. Furthermore, unmarried men were overrepresented among the study cohort. These findings support previous observations indicating that short term workers share atypical features related to high mortality from various causes. It is suggested that mortality in this subgroup should be analysed separately in occupational studies.
doi: 10.1136/oem.44.9.602pmid: 3311128
The aim of the present study was to evaluate the association and impact of occupational exposure and diseases of the shoulder and neck. Prevalence rates, odds ratios, aetiological fractions, and their confidence intervals were computed for pooled and non-pooled data of previous published reports. By comparison with office workers and farmers, dentists had an increased odds ratio for cervical spondylosis (two studies) and for shoulder joint osteoarthrosis. Meat carriers, miners, and "heavy workers" also had significantly higher rates of cervical spondylosis compared with referents. Compared with iron foundry workers, civil servants had a significant odds ratio (4.8) of cervical disc disease and a 0.79 aetiological fraction. Whether this was due to exposure or healthy worker effect was not clear. In four occupational groups with high shoulder-neck load an odds ratio of 4.0 was found for thoracic outlet syndrome with an aetiological fraction of 0.75. Rotator cuff tendinitis in occupational groups with work at shoulder level (two studies) showed an odds ratio of 11 and an aetiological fraction of 0.91. Keyboard operators had an odds ratio of 3.0 for tension neck syndrome (five studies). Unfortunately, owing to the scanty description of the work task, the exposure could be analysed only by job title. Examination of published reports shows clearly that certain job titles are associated with shoulder-neck disorders. High rates and aetiological fractions for rotator cuff tendinitis and tension neck syndrome suggest that preventive measures could be effective. Although job descriptions are brief, the associations noted suggest that highly repetitive shoulder muscle contractions, static contractions, and work at shoulder level are hazardous exposure factors. In reports of cross sectional studies of occupational shoulder-neck disorders presentation of age, exposure, and effect distribution may help for future meta-analysis.
Thun, M; Tanaka, S; Smith, A B; Halperin, W E; Lee, S T; Luggen, M E; Hess, E V
doi: 10.1136/oem.44.9.611pmid: 2959311
Carpet layers comprise less than 0.06% of the United States workforce yet they submit 6.2% of compensation claims for traumatic knee inflammation. Their work involves multiple sources of acute and chronic knee trauma including kneeling, pressure from sharp objects, and use of a device called a "knee kicker" to stretch wall to wall carpet. To characterise the knee morbidity in carpet layers and to identify occupational risk factors, a questionnaire was completed by 112 carpet and floor layers, 42 tile and terrazo setters, and 243 millwrights and bricklayers (MWBL). The MWBL comparison workers seldom kneel and do not use a knee kicker. Physical and xray examinations were conducted on a subset of 108 respondents to validate the questionnaire responses. Compared with the MWBL, carpet layers reported more frequent bursitis (20% v 6%), needle aspiration of knee fluid (32% v 6%), and skin infections of the knee (7% v 2%). A score indicating frequency of using the knee kicker was the only statistically significant predictor of bursitis, whereas the score for kneeling was one of several predictors of knee aspiration and skin infections of the knee. These data suggest that carpet and floor layers experience substantially more knee morbidity than other occupational groups, and that kneeling and use of the knee kicker are risk factors providing opportunities for prevention.
doi: 10.1136/oem.44.9.621pmid: 3499174
The prevalence of non-malignant asbestos related disorders was studied in a group of men who had been subjected to different levels of asbestos exposure when working at an electrochemical plant producing nitric acid sometime between 1928 and 1970. There were 153 men eligible for an initial clinical examination in 1979-80 and that group has been followed up to 1985. Among the cohort members the "accumulated prevalence" of lung fibrosis alone or in combination with pleural plaques and of "pleural plaques only" was 24.2% and 24.8% respectively. The subgroup with the heaviest exposure had a total prevalence of asbestos related disorders of 82.5%. Only study subjects with lung fibrosis had statistically significant increased prevalences of respiratory symptoms. All subgroups from the study population, however, had mean spirometric values under the age, height, and smoking specific predicted means. Subjects with heavy asbestos exposure and current smoking had a prevalence of three or more respiratory symptoms of 28.8% compared with 5.6% among lightly exposed never smokers. Pleural crepitations at chest auscultation were more prevalent among subjects with radiologically visible asbestos related disorders than among study subjects with normal chest x ray films. During the follow up from 1980 to 1985, three cases of lung cancer, two of pleural malignant mesothelioma, and one of stomach cancer were found among the cohort members.
Botham, P A; Davies, G E; Teasdale, E L
doi: 10.1136/oem.44.9.627pmid: 3663527
The pattern of incidence of allergy to laboratory animals (ALA) has been studied prospectively in 383 individuals occupationally exposed to rodents and to rabbits. The incidence of the disease after one year of exposure to animals fell from 37% in 1980 and 1981 to 20% in 1982, 10% in 1983, and 12% in 1984. A similar reduction was noted after two and three years of exposure in the 1982 and 1983 cohorts. The reduction in incidence coincided with the introduction of a site order and code of practice for working with animals and an education programme designed to focus awareness on the problem. Although rats were believed to be the major cause of the disease, objective measurements of IgE antibody against rat urine allergen were positive in only half the symptomatic individuals. Antibodies to different animal derived allergens were, however, found in several other personnel. Symptoms were generally of mild or moderate intensity and affected mainly the nose, eyes, and skin; chest symptoms were found in only 1.6% of the exposed population. A study of the influence of atopy on the development of ALA showed that after one year of exposure to animals a significantly greater proportion of atopic individuals became symptomatic (19-43% compared with 3-6%). After two and three years of exposure, however, this discrepancy was not maintained, with more non-atopic individuals developing the disease.
Shima, S; Morita, K; Tachikawa, S; Ito, T; Kurita, H; Yoshida, T; Kato, Y; Yamamoto, Y
doi: 10.1136/oem.44.9.633pmid: 3663528
The effect of zirconium (Zr) on the humoral immune response was studied by measuring the level of IgM-plaque forming cells (IgM-PFC) against sheep red blood cells (SRBC) in the spleen of C57 BL mice intraperitoneally injected with zirconium oxychloride. Two experiments, a single injection of zirconium oxychloride of 1/5, 1/10, 1/50, and 1/100 of the LD50 for intraperitoneal injection and continuous injection of 1/20, 1/40, and 1/80 of the LD50 every other day for two or four weeks in mice, were carried out. In the case of a single injection zirconium oxychloride was intraperitoneally injected on days -1, 0, +1, +2, and +3 in relation to SRBC immunisation. The following conclusions may be drawn from this study: (1) Zr was shown to have an adjuvant like activity in relation to the humoral immune response, at least to IgM antibody production; (2) this effect was recognised not only with a single injection with Zr but also after continuous injection; (3) a single injection of Zr was more effective when the mice were treated with Zr 24 hours before or after SRBC immunisation; and (4) with regard to an injected dose of Zr, it was shown that a lower dose (1/50, 1/100 of the LD50 for a single injection and 1/40, 1/80 of the LD50 for continuous injection) led to a more enhanced level of IgM-PFC than a higher dose (1/5, 1/10 of the LD50 for a single injection, and 1/20 of the LD50 for continuous injection).
Triebig, G; Csuzda, I; Krekeler, H J; Schaller, K H
doi: 10.1136/oem.44.9.638pmid: 2822076
A longitudinal study was performed to examine whether chronic occupational exposure to pentachlorophenol (PCP) or its compounds causes measurable alterations in the conduction velocity in peripheral nerves as an "adverse effect." In total, the results of nerve conduction velocity (NCV) determinations in 1980 and 1984 in 10 subjects (7 men, 3 women) who had been exposed for an average of 16 years (range 4-24) were available. The concentrations of PCP in the air at the workplace varied between 0.3 and 180 micrograms/m3 and were thus below the maximum allowed concentration (MAK value) of 500 micrograms/m3. The biological monitoring carried out showed the following results: PCP in the serum: 38-1270 micrograms/l; PCP in the urine: 8-1224 micrograms/l. Compared with the upper normal limits (PCP in the serum 150 micrograms/l, PCP in the urine 60 micrograms/l), distinct internal exposure to PCP has resulted in some of the employees. Determinations of the NCV of motor and sensory nerve fibres (ulnar, median, peroneal, and sural nerve) were always in the normal range. A significant difference in the NCV for the period 1980-4 could not be detected. In addition, the correlation analyses did not show any hints of "dose-effect relations." It is concluded that occupational exposure to PCP over several years in the concentrations observed probably do not lead to any adverse effects on the peripheral nervous system.
Showing 1 to 10 of 14 Articles