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C Hogstedt

Publications and source records attributed to C Hogstedt.

At least 37 records · Page 2Linked to original sources
PubMed1995

An index of past asbestos exposure as applied to car and bus mechanics.

Different ways to describe historic fibre exposure from asbestos-containing friction materials were studied and compared for a group of 103 car and bus mechanics with more than 20 years employment and 15 years of asbestos exposure. A model was constructed to calculate cumulative asbestos exposure from friction materials including duration, intensity and exposure last year. The model is a combination of an additive and a multiplicative model, where an asbestos index was constructed that takes both near field and far field exposure into consideration. The model was based upon data from the international literature and quantitative asbestos measurements performed 1976-1988 in Swedish car repair workshops. The fibres were counted by phase-contrast microscopy with fibre criteria of length > 5 microns and aspect ratio > or = 3:1. The mechanics' fibre exposure at 398 repair workshops during a period of 48 years were calculated using the model. The mean cumulative exposure was estimated to be 2.6 f ml-1 * year. The annual cumulative exposure was highest for truck mechanics in the early 1960s. The car mechanics had a time-weighted average fibre exposure range of 0.11-0.41 f ml-1 (mean 0.21 f ml-1) in 1965 compared to 0.003-0.08 f ml-1 (mean 0.021 f ml-1) in 1985. In order to validate the model, the mechanic's fibre exposure estimated using the model were compared with representative asbestos exposure measurements for car mechanics during the 1960s and the 1970s (correlation coefficient = 0.69). Five lung physiological variables (FVC, TLC, FEV1, TLco and CV%) were used to study exposure-response relationships. None of the exposure parameters suggested any significant relationship between exposure and decrease in lung function.

Adult↗
PubMed1995

Cancer incidence, mortality and exposure-response among Swedish man-made vitreous fiber production workers.

OBJECTIVE: The objective of this study was to provide an extended follow-up of workers in three Swedish plants producing man-made vitreous fibers (MMVF). METHOD: Mortality and cancer incidence was investigated among 3539 male and female workers, employed for at least one year before 1978. Mortality was followed from 1952 to 1990 and cancer incidence from 1958 to 1989. National and regional mortality and cancer incidence rates were used to calculate the expected numbers. RESULTS: Twenty-seven lung cancer deaths were observed compared with 23 expected (standardized mortality ratio 117, 95% confidence interval 81-176), based on regional mortality. With a latency time of 30 years, the lung cancer risk was significantly elevated, but not trend was found for the standardized mortality ratio with increasing duration of exposure to MMVF. The lung cancer and stomach cancer mortality was higher in the rock wool industry than in the fiber glass industry. Fiber exposure from 1938 to 1990 was estimated in the two rock wool plants by applying a model for historical fiber exposure estimation, specific for different job titles in the rock wool production industry. No relationship was found between individually cumulated rock wool fiber exposure and lung cancer or stomach cancer risk. CONCLUSIONS: The numbers of lung cancers and stomach cancer cases were low and did not therefore allow more general conclusions regarding the cancer hazard for exposed workers. A large European study in progress will probably allow more precise conclusions.

Adult↗
PubMed1995

Neuropsychiatric function of housepainters with previous long-term heavy exposure to organic solvents.

Neuropsychiatric effects were examined among 206 men, of whom 135 had been house painters and 71 had been house carpenters, affiliated with their respective trade unions for at least 10 years before 1970. Their lifetime organic solvent exposure was evaluated through the aid of an interview. Relevant potential confounding factors were accounted for in the statistical analysis. Neuropsychiatric symptoms compatible with chronic toxic encephalopathy were more common among the painters than among the carpenters, and these symptoms became increasingly prevalent with increasing cumulative solvent exposure. On only one of 12 psychometric tests, block design, did the painters perform worse than the carpenters, and in this test the painters' performance deteriorated with increasing cumulative exposure. For the majority of the psychometric tests, and for the coordination tests, there were no differences between the painters and carpenters, but the painters with "low" exposure tended to show better, and "heavily" exposed painters worse, results than the carpenters. The 52 painters with the heaviest cumulative exposures and 45 carpenters were examined for psychiatric diagnosis according to DSM-III, with electroencephalography and auditory evoked potential, P-300. Three painters and two carpenters had diagnoses compatible with an organic mental disorder. There were no overall differences between the painters and carpenters, either for the visually examined electroencephalograms or the P-300 latencies. The excess of neuropsychiatric symptoms among the painters was probably causally linked to solvent exposure. However, these symptoms seemed only rarely, if ever, serious enough to entail a psychiatric diagnosis. Concerning other outcomes, the investigation may not lead to a determination of whether the exposure-response relationship among the painters, with no difference between the entire group of painters and carpenters, is caused by solvent exposure or by selection factors within the group of painters.

Adult↗
PubMed1994

Mortality and cancer incidence in Stockholm fire fighters.

Fire fighters are exposed to irritating, asphyxiating, and toxic gases and aerosols, to psychological stress, and to physically demanding work. Due to differences in fire fighting techniques, exposure conditions for fire fighters differ among different countries. The purpose of this investigation was to study cancer incidence and mortality in fire fighters who have been working with fire fighting methods used in Sweden from the beginning of this century onwards. All male fire fighters employed for at least 1 year in the City of Stockholm during 1931-1983 were traced, and an index of the number of fires fought was calculated for each individual. The mortality during 1951-1986 (among 1, 116 fire fighters) was lower than expected (SMR = 82; 95% confidence interval 72-91) compared with local mortality rates, with a low mortality in circulatory diseases, obstructive lung diseases, violent deaths, and suicides. The cancer incidence in 1958-1986 was equal to the expected (SMR = 100; 95% confidence interval 83-119). However, an excess of stomach cancer (18 observed vs. 9.37 expected; SMR = 192, 95% CI 114-304) was observed. There was also a tendency for higher incidence and mortality in stomach and brain cancer with increasing number of fires. There were four deaths from brain cancer compared to 0.8 expected (SMR = 496; 95% CI 135-1270) in the highest exposure category. Fire fighters are, however, not systematically exposed to known stomach or brain carcinogens, and the results need confirmation in further studies with extensive exposure evaluations.

Aged↗
PubMed1994

Has the Scandinavian solvent syndrome controversy been solved?

This article discusses the "Scandinavian solvent syndrome" and reviews epidemiologic studies on occupational solvent exposure and two related outcomes. High cumulative exposure to organic solvents in the 1960-1970s was related to early retirement from neuropsychiatric disorders, but solvent exposure alone was an unlikely cause of more severe dementia conditions. Heavy alcohol consumption seemed to modify the effect on solvent-related brain disorders strongly, but no reports exist of alcohol consumption as a confounding factor. Many cross-sectional and experimental studies support functional impairment from high solvent exposure. The mists and myths around the "Scandinavian solvent syndrome" can now be cleared up: it was not a uniform syndrome, it might be reversible in many cases, it is not confined to the Scandinavian countries, the risk of more severe dementia is substantial for combined high solvent exposure and excessive alcohol consumption, and many solvent-exposed workers receive early retirement due to solvent-related neuropsychiatric disorders.

Air Pollutants, Occupational↗
PubMed1994

Updated and expanded Swedish cohort study on trichloroethylene and cancer risk.

There is limited evidence for mutagenicity and carcinogenicity of trichloroethylene (TRI) in experimental test systems. Whether TRI is a human carcinogen is unclear, however. This paper presents an update and extension of a previously reported cohort of workers exposed to TRI, in total 1670 persons. Among men (n = 1421), the overall standardized mortality ratio (SMR) and cancer morbidity ratio (SIR) were close to the expected, with SMR, 0.97; 95% confidence interval (CI), 0.86 to 1.10; and SIR, 0.96; 95% CI, 0.80 to 1.16, respectively. The cancer mortality was significantly lower than expected (SMR, 0.65; 95% CI, 0.47 to 0.89), whereas an increased mortality from circulatory disorders (cardiovascular, cerebrovascular) was of borderline significance (SMR, 1.17; 95% CI, 1.00 to 1.37). No significant increase of cancer of any specific site was observed, except for a doubled incidence of nonmelanocytic skin cancer without correlation with the exposure categories. In the small female subcohort (n = 249), a nonsignificant increase of cancer and circulatory deaths was observed (SMR, 1.53 and 2.02, respectively). For both genders, however, excess risks were largely confined to groups of workers with lower exposure levels or short duration of exposure or both. It is concluded that this study provides no evidence that TRI is a human carcinogen, ie, when the exposure is as low as for this study population.

Adult↗
PubMed1993

Incidence of myocardial infarction and mortality from specific causes among bus drivers in Sweden.

Previous studies have indicated that urban bus drivers have an increased risk of coronary heart disease. In the present investigation two separate studies were carried out. In the first study the mortality from myocardial infarction (MI), as well as from other causes for all male bus drivers in Sweden (9446), was investigated and compared to those of other employed men over a 15-year period. A 50% increase in mortality from MI was observed among drivers in Stockholm and Göteborg and Bohus counties, the two counties where the two largest cities in Sweden are situated. No increased mortality from lung cancer, any cancer (all sites combined), or from all causes combined was observed for these drivers. For bus drivers in the predominantly rural areas no excess mortality from MI, or any other cause, was observed. In the second study the incidence of MI among male bus drivers, as compared with other employed men, was studied in five Swedish counties by case referent methods. An increased incidence of first events of MI, (relative risk = 1.6, 95% confidence interval (CI) 1.1-1.9) was observed for bus drivers in Stockholm county. According to our results, urban bus drivers thus have an increased risk of developing MI. The findings also suggest that factors in the work environment of urban bus drivers may contribute to this increased risk. Factors of possible importance are job strain, irregular working hours, a sedentary job, automobile exhaust fumes, and noise.

Automobile Driving↗
PubMed1993

Mortality and incidence of cancer in a cohort of Swedish chimney sweeps: an extended follow up study.

Despite 200 years of efforts to regulate safety in this occupation, chimney sweeps have increased mortality from cancer, ischaemic heart disease, and respiratory disease. Mortality and incidence of cancer were examined in a cohort of 5542 Swedish chimney sweeps employed through their national trade union at any time between 1918 and 1980. Previous studies of this cohort found increased risks of ischaemic heart disease, respiratory disease, accidental deaths, and various neoplasms. By increasing follow up, we sought to increase the power of the study and examine disease time trends. Mortality analysis was extended 7.5 years to cover the period 1951-90; cancer incidence analysis was extended six years to cover the period 1958-87. New findings include increased incidence and mortality of prostate cancer (SMR 169, 95% CI 106-256, 22 observed) and increased incidence of total haematolymphatic cancers (SIR 151, 95% CI 106-209, 36 observed). When only the most recent follow up period was analysed, previously observed risks persisted for total lung cancer (SIR 178, 95% CI 99-293), oat cell lung cancer (SIR 240, 95% CI 103-472), bladder cancer (SIR 247, 95% CI 131-422), and oesophageal cancer (Obs/Exp = 2/1.1). Mortality from ischaemic heart disease (SMR 98, 95% CI 76-123) and respiratory disease (SMR 111, 95% CI 56-199) declined during recent follow up, although significant excess mortality remained during analysis of the entire study period (ischaemic heart disease SMR 128, 95% CI 112-145; respiratory disease SMR 159, 95% CI 115-213). In analyses of the entire study period, risks of ischaemic heart disease and lung, bladder, and oesophageal cancer were adjusted for smoking; oesophageal cancer was also adjusted for use of alcohol. All risks remained significantly raised. Exposure-response analyses showed significant positive associations between duration of employment and risks for mortality from lung, oesophageal, and total cancer. Chimney sweeps remain at increased risk for cancers of the lung, oesophagus, and bladder. Our study supports a casual role for exposure to chimney soot, which contains carcinogens including polycyclic aromatic hydrocarbons. Extended follow up of this cohort now shows increased risks of prostate and haematolymphatic cancers.

Adolescent↗
PubMed1993

Shoulder tendinitis and its relation to heavy manual work and exposure to vibration.

Three categories of construction industry workers (54 bricklayers, 55 rockblasters, and 98 foremen) were compared in a cross-sectional study. In a structured interview they reported exposure to loads lifted, vibration, and years of manual work. They were also subjected to a clinical investigation including medical history and a detailed shoulder examination. Among the rockblasters 33% had signs of tendinitis in the left and 40% in the right shoulder. Among the bricklayers and foremen 8-17% had signs of shoulder tendinitis. In a multiple logistic regression being a rockblaster compared with being a foreman showed an odds ratio (OR) of 3.33 for left-sided and 1.71 for right-sided shoulder tendinitis. Vibration exposure yielded an OR of 1.84 and 1.66 for the left and right sides, respectively. Vibration exposure or work as a rockblaster seemed to be risk indicators for tendinitis of the shoulders.

Adult↗
PubMed1992

Lung cancer risk among workers exposed to man-made mineral fibers (MMMF) in the Swedish prefabricated house industry.

Mortality and cancer incidence was investigated among 2,807 workers, employed for at least one year before 1972, at 11 Swedish companies manufacturing prefabricated wooden houses. A total of 1,068 workers had been exposed to man-made mineral fibers (MMMF) used for insulation. Mortality was followed from 1969 to 1988 and cancer incidence from 1969 to 1985. Exposure conditions were investigated at all plants. There were 14 deaths from lung cancer in the total cohort, whereas 20.7 would be expected (SMR = 68; 95% CI:37-113), based on regional mortality. After a latency of 20 years of more, two lung cancer cases had occurred among all workers exposed to MMMF, whereas 4.3 would be expected (SMR = 46; 95% CI: 5-168). The exposure levels that have prevailed do not seem to be associated with an increased lung cancer rate, but extended follow-up is necessary for a definitive evaluation.

Cohort Studies↗
PubMed1992

Radiographic osteoarthrosis in the acromioclavicular joint resulting from manual work or exposure to vibration.

The hypothesis that manual work and exposure to vibration are antecedents to the development of osteoarthrosis was assessed employing a cross sectional study design. The frequency of osteoarthrosis in the acromioclavicular joint was studied in three groups of workers in the construction industry. Two groups were manual workers (54 bricklayers and 55 rock blasters); the third group consisted of 98 foremen. The radiographic appearance of the right and left acromioclavicular joints was classified into one of five grades of osteoarthrosis. A protocol was developed to assess exposure on the basis of job title, years of manual work, total weight lifted during working life, and total hours of exposure to vibrating tools. Odds ratios for job titles (manual worker v foreman) and for years of manual work as indicators of exposure were of similar magnitude of around 2.5. Construction workers who had lifted more than 709 tonnes had an increased risk of developing severe osteoarthrosis of the right acromioclavicular joint, odds ratio: 2.62 (95% confidence interval (95% CI), 1.13-6.06). The odds ratio for the left side was 7.67 (95% CI, 2.76-21.34). In the analysis of vibration exposure, workers who had been highly exposed to vibration had an odds ratio of 1.99 (95% CI, 1.00-3.92) on the right side and 2.20 (95% CI, 1.07-4.56) on the left. This effect almost disappeared after simultaneous adjustment for manual work. Occupational and ergonomic factors, such as the sum of lifted tonnes during working life, job title, and the sum of years of manual work seem to be risk factors for osteoarthrosis of the acromioclavicular joint, whereas vibration alone was a weaker risk factor.

Acromioclavicular Joint↗
PubMed1992

Does long-term concrete work cause silicosis?

The machining of cast concrete often produces heavy exposure to respirable silica dust. Work with concrete in general results in considerably less exposure, however, and only a few cases of silicosis due to work with concrete have been reported. Telephone interviews with detailed questions on occupational history were made with 271 construction workers specializing in concrete work for more than 20 years, and exposure data were evaluated for different work tasks. The mean cumulative exposure of subjects to silica was estimated to be 2.4 mg.years.m-3. Chest radiographs were classified according to the International Labour Office classification. There was no suspicion of silicosis for any of the workers. The risk of contracting silicosis from work with concrete in the Swedish construction industry in recent decades is considered to be slight and does not justify general, periodic chest radiographic screening.

Construction Materials↗
PubMed1992

Epidemiology of occupational neurobehavioural hazards. Methodological experiences from organic solvent research.

Neurobehavioral hazards have been identified since long in occupational health, e.g. lead, mercury, certain solvents, and many others agents. There are reviews and books on "Occupational neurology" or "Prevention of neurotoxic illness in working populations". Many methods have been applied for studies of the central and peripheral nervous systems in humans: registered diagnoses, questionnaire ratings, clinical evaluation, psychometric tests, neurophysiological and neuroradiological methods, cerebrospinal fluid components etc. Some neurological disorders are well defined, while neuropsychiatric syndromes often are less precisely diagnosed. Decreased subclinical test results in exposed groups might predict an increased risk for later, more serious disorders but the longitudinal information on clinical importance is often lacking. Some historical lessons from the epidemiology of occupational neurology will be repeated and a few reflections on the suitability of different diagnostic entities for epidemiological research shall be made. Since the beginning of the 1970s' a number of studies from the Scandinavian countries have demonstrated long-term neurobehavioral effects from working conditions with relatively moderate exposure to organic solvents. Similar findings have been verified in studies from some countries outside Scandinavia while other studies have been inconclusive. Those results have caused considerable controversy and have been discussed at international conferences and in scientific journals. Very different outcomes have been investigated in those solvent studies, however, and most studies have had a cross-sectional design with inherent problems. The exposure has been assessed in different ways, e.g. by years of occupation, hygienic measurements of the present working conditions, biological monitoring, retrospective assessments on qualitative or semi-quantitative scales. Sometimes single solvent exposures have been studied but most of the studies concern mixtures of solvents from aromatic and aliphatic hydrocarbons. As the designs have varied the exposure assessment has been crude and many different outcomes have been studied, it is hardly surprising that the results and the interpretations have differed. The first results from a comprehensive investigation on 135 solvent exposed painters and 71 carpenters as referents, selected from active members of the respective trade union 1965-70 and investigated in the late 80s, will be presented. Clinical, including psychiatric, diagnostic work up and neuropsychological as well as neurophysiological tests have been performed. Psychological test results from military conscripts at age 19 were available for all. The individual exposure history has been carefully assessed.(ABSTRACT TRUNCATED AT 400 WORDS)

Case-Control Studies↗
PubMed1991

Occupation and osteoarthrosis of the hip and knee: a register-based cohort study.

A register-based cohort study was performed to investigate if men and women in certain occupations with high physical workload had increased risks of developing severe symptomatic osteoarthrosis of the hip and knee, resulting in hospital care. The study population consisted of 250,217 people from the 1980 census, in blue-collar occupations, who had reported the same occupation in the 1960 and 1970 censuses. The study population was followed for hospital care for osteoarthrosis of the hip and knee during 1981-1983 by linkage to the Swedish Hospital Discharge Register. Different blue-collar occupations were classified as high or low with regard to exposure to forces acting on the hip and knee and the frequencies of the outcomes were compared. Male farmers, construction workers, firefighters and some food processing workers had an excess risk of hospitalization due to osteoarthrosis of the hip. Male farmers, construction workers and firefighters also had increased risks of osteoarthrosis of the knee. Female mail carriers had an excess risk of osteoarthrosis of the hip, and female cleaners, of osteoarthrosis of the knee. The findings support the hypothesis that heavy physical work load contributes to osteoarthrosis of the hip and knee.

Cohort Studies↗
PubMed1991

Coxarthrosis and physical work load.

A case-referent study was performed on the possible relationship between physical work loads and an increased risk of developing coxarthrosis. The cases were 239 male recipients of a hip prosthesis as a result of severe idiopathic coxarthrosis; the referents were 302 men randomly selected from the general population. The work load was assessed through an interview and a self-administered questionnaire on the men's specific work periods. Men highly exposed to dynamic or static work loads had an increased relative risk of 2.42 (95% confidence interval 1.45-4.04) for developing coxarthrosis when compared with men with low exposure. Men with high exposure to heavy lifting between the ages of 30 and 49 years had the highest relative risk, 3.31 (95% confidence interval 1.97-5.57). Long-time exposure to physical work loads seems to be a risk factor for severe coxarthrosis among men.

Adult↗
PubMed1990

Increased risk of urothelial cancer in Stockholm during 1985-87 after exposure to benzene and exhausts.

In a population-based case-referent study of urothelial cancer in Stockholm during 1985-87, information was obtained from 80% of 320 identified male cases and 79% of 363 selected male referents. Industrial exposures were assessed for each subject by an industrial hygienist on the basis of questionnaire data. Exposure to benzene (any annual dose) gave a relative risk (with 95% confidence interval) of 2.0 (1.0-3.8). The highest risk was seen for a high annual dose. Subjects exposed to both diesel and petrol exhausts (moderate/high annual dose) had a relative risk of 7.1 (0.9-58.8). However, adjusting for benzene changed the relative risk to 5.1 (0.6-43.6). It might be rewarding to consider whether benzene from petrol confounds the associations previously suggested between exhausts and urothelial cancer. Exposure to polychlorinated biphenyls (PCB) gave a relative risk of 3.3 (0.6-18.4).

Benzene↗