Biomedical subjects

C G Ohlson

Publications and source records attributed to C G Ohlson.

28 records · Page 2Linked to original sources

PubMed1989

Olfactory function in painters exposed to organic solvents.

The olfactory receptor cells are in direct contact with the exterior environment, and some chemical agents can impair olfactory function. The olfactory function of 54 painters exposed to organic solvents was compared with that of 42 unexposed referents. A new clinical test validated for the sense of smell was used, the University of Pennsylvania Smell Identification Test. Age, smoking habits, exposure to organic solvents, and medical disorders of importance for the sense of smell were recorded. The painters had a somewhat lower test score than the referents. However, the influence of the exposure variable was not statistically significant in a multiple regression analysis including age and smoking habits. The exposure to organic solvents was low, and therefore an effect of high exposure on olfactory function cannot be ruled out. Since some of the painters had earlier been highly exposed, the effects of high exposure are likely to be reversible.

Adult↗

PubMed1988

Disturbed iron metabolism among workers exposed to organic sulfides in a pulp plant.

The aim of this study was to investigate a possible relationship between exposure to sulfides and disturbances of the synthesis of heme and the erythrocytes. Eighteen workers exposed to sulfides at a pulp and paper plant were examined and compared with individually matched referents from a thermomechanical pulp plant without such exposure. The exposure levels of methylmercaptan, dimethylsulfide, and dimethyldisulfide were low. However, five subjects were exposed to high levels of short duration, and their data were analyzed separately. The activity of the enzymes delta-aminolevulinic acid synthase and heme synthase in reticulocytes, characteristics of the erythrocytes, and the iron status were analyzed. A minor decrease, not statistically significant, was observed for the enzymes among the five highly exposed subjects. However, the concentrations of iron and transferrin were elevated and the concentration of ferritin was low in comparison to the corresponding levels of the referents. This combination will not occur spontaneously. A previous study indicated that sulfides may inhibit heme synthesis, and the present study suggests that they may also disturb iron metabolism.

5-Aminolevulinate Synthetase↗

PubMed1985

Lung cancer among asbestos cement workers. A Swedish cohort study and a review.

A cohort study of 1176 Swedish asbestos cement workers did not indicate any asbestos related excess mortality. Possible explanations of the negative outcome are relatively low exposure levels and the predominant use of chrysotile in production. Such a tentative conclusion is supported by a review of five mortality studies of workers exposed to asbestos cement that report considerable differences in relative risks for lung cancer. These differences could be explained by various degrees of cumulative exposure, the amount of amphiboles in the production, and methodological shortcomings. A median exposure of 10-20 fibre-years does not seem to cause an increased risk of lung cancer, particularly when only chrysotile is used.

Asbestos↗

PubMed1985

Ventilatory decrements in former asbestos cement workers: a four year follow up.

A four year follow up of the ventilatory function in former asbestos cement workers has been performed to determine whether any further decrease occurred after cessation of exposure. Seventy five of 125 subjects were eligible for re-examination and were compared with local referents. None showed signs of asbestosis but 32% had pleural plaques at the renewed examination. Cumulative asbestos exposure calculated as fibre x years had been estimated individually in the original examination. After adjustment for age, height, tracheal area, and smoking category the FVC and FEV1 for all exposed subjects were on average 7% v 6% less than predicted from the referents and twice as much for the subjects with the highest exposure. The four year declines in FVC and FEV1 were larger than in the referents, significantly so for FEV1. There were no significant correlations between pleural plaque and ventilatory function after adjustment for exposure. Thus the age adjusted reduction in ventilatory function had progressed during the follow up period despite the cessation of exposure and the lack of radiological signs of asbestosis.

Adult↗

PubMed1985

Participants and non-participants of different categories in a health survey. A cross-sectional register study.

Participants and non-participants in a health survey of asbestos cement workers were compared, using data from public registers, i.e. variables of socio-medical relevance. The plant closed down in 1976 and 3 years later all living subjects, 985 persons, were offered a health examination. The participation rate was 57%. The non-participants were divided into four categories: I, those who answered the invitation but refused to participate; II, those who did not answer even after three invitations; III, those who answered and accepted but did not participate; and IV, those who participated partly. A very consistent pattern of differences between participants and non-participants was observed, the latter being significantly more often registered for Public Assistance, for heavy drinking habits or criminal offences, and had significantly lower incomes and occupational status. The sickness absence, however, was not significantly shorter among the participants. The non-participating categories II and III differed most from the participants. Category I was more similar to the participants than to the other non-participating categories. This heterogeneity of the non-response/non-participation concept should be considered when health survey data are interpreted.

Absenteeism↗

PubMed1984

Decreased lung function in long-term asbestos cement workers: a cross-sectional study.

The effect on lung function of exposure in an asbestos cement plant was investigated in male workers, employed more than 10 years. The exposed group was selected to exclude subjects with pneumoconioses and ex-smokers and consisted of 77 smokers and 48 never-smokers. Referents were chosen from plants where asbestos had not been in use and restricted to those without X-ray signs of chest disease. The primary type of asbestos used was chrysotile and the general dust level in the two decades 1950-1970 seems to have been around 10 mg/m3 while the asbestos fiber concentration averaged 2 fibers/ml. The mean differences between exposed and referents were statistically significant for forced vital capacity and forced expiratory volume, -0.25 and -0.30 liters, respectively, after adjustment for age, height, tracheal area, and smoking category. No significant differences were detected between those with and without pleural plaques. Smokers and never-smokers were similarly affected. In conclusion, the group exposed to dust with comparatively low asbestos fiber concentration had a minor impairment of lung function, mainly due to obstructive changes.

Air Pollutants, Occupational↗

PubMed1984

Mortality among asbestos-exposed workers in a railroad workshop.

The mortality experience of a cohort of 3 297 railroad maintenance shopworkers exposed to asbestos was investigated. The study period was 1951-1980, and the vital status was assessed for 99.6% of the men. Individual estimates of cumulative asbestos exposure were based on detailed records on work tasks and divisions. Dust measurements were scanty in earlier decades, and estimates of average fiber levels were therefore based on information on the amount and kind of asbestos used, job descriptions, and interviews with older workers. The overall mortality was lower than expected from the national death rates (standardized mortality ratio = 82). The mortality from lung cancer increased as cumulative exposure increased in consistent dose-response relationships. Employment times of less than 30 years in workplaces with moderate levels of mainly chrysotile asbestos was not associated with any apparent increase in the risk of lung cancer. A subgroup exposed for more than 30 years in workplaces repairing steam engines, where amphiboles were used as well, had a standardized mortality ratio of 192 for lung cancer. This figure may be an underestimation due to healthy worker selection and fewer smokers than normal. The "true" standardized mortality ratio was estimated to be about 300. Five cases of mesothelioma were observed.

Aged↗

PubMed1981

Parkinson's disease and occupational exposure to organic solvents, agricultural chemicals and mercury--a case-referent study.

Parkinson's disease has been associated with heavy occupational exposure to carbon disulfide, and this solvent, as well as other organic solvents, may cause neurotoxic effects. Therefore, the hypothesis was raised that organic solvents in general may be associated with Parkinson's disease. A case-referent study design was applied, and some other suspected exposures were studied as well. The diagnosis registers of two Swedish hospitals were used as the source of subjects. Male in-patients with Parkinson's disease (the cases) or subarachnoid hemorrhage (referents), with symptom appearance between 35-69 a of age and residence in the vicinity of the hospitals, were included in the study. Occupational exposure to the chemicals under study were determined from questionnaire answers of 91 cases and 75 referents. No differences in exposure frequency to organic solvents in general were observed, but three cases had been exposed to carbon disulfide compared to none of the referents. Six cases, but only two referents, had been exposed to mercury, and further exploration of a possible association between exposure to mercury and Parkinson's disease is recommended. The outcome of the study does not support the hypothesis that occupational exposure to organic solvents in general increases the risk of Parkinson's disease, but the confidence intervals of the odds ratios do not rule out such possibilities.

Adult↗

PubMedDate not supplied

Testicular cancer and occupational exposures with a focus on xenoestrogens in polyvinyl chloride plastics.

In a case-control study of 148 cases of testicular cancer and 314 healthy controls information was collected on lifetime working histories and specific exposures. The main finding was a six-fold increase in the risk for seminoma, one type of testicular cancer, among plastic workers exposed to polyvinyl chloride (PVC). No overrisks were observed for other plastics than PVC. There may be an aetiological link to xenoestrogens, i.e. chemicals in the environment with oestrogenic properties. Phthalates are used in PVC as plasticizer and have oestrogenic properties that could promote the growth of endocrine sensitive tumour cells. However, this "endocrine disruptors" hypothesis must be further evaluated in experimental models with regard to the causative mechanisms of the oestrogenic tumour promotion.

Adult↗

PubMedDate not supplied

Stress markers in relation to job strain in human service organizations.

BACKGROUND: Workers in human service organizations are often confronted with conflicting demands in providing care or education. The aim of this cross-sectional study was to relate levels of endocrine stress markers to perceived job strain in two human service organizations. METHODS: Employees in two local units of the social insurance organization and two local units of the individual and family care sections of the social welfare in Sweden were selected and 103 employees participated (56% participation rate). The perceived job strain was assessed with a standardized questionnaire containing questions of the demand-control model. Questions specially designed to measure emotional demands were also included. The stress markers cortisol, prolactin, thyroid-stimulating hormone, testosterone and IgA and IgG were analysed in blood samples. RESULTS: The main finding was an association between high emotional strain and increased levels of prolactin. The levels of cortisol, but none of the other four stress markers, increased slightly with emotional strain. CONCLUSIONS: Emotional strain experienced in human service work may cause psychological stress. The increase in prolactin was modest but consistent with findings in other published studies on stress-related endocrine alterations.

Adult↗