Mortality among Swedish chimney sweeps (1952-2006): An extended cohort study

Unit of Occupational Medicine, Institute of Environmental Medicine, Karolinska Institutet, Norrbacka, Level 4, SE-171 76 Stockholm, Sweden.
Occupational and environmental medicine (Impact Factor: 3.27). 06/2011; 69(1):41-7. DOI: 10.1136/oem.2010.064246
Source: PubMed


We extended a cohort study of Swedish chimney sweeps and prolonged follow-up in order to increase power and study those first employed after 1950 when oil began to replace wood as a main fuel for heating in Sweden.
Male Swedish chimney sweeps who were members of the national trade union in 1981-2006 were identified (n=1087) and included to a previous cohort of those employed in 1918-1980 (n=5287). All employment histories were updated, and the total extended cohort (n=6374) was linked to the registers of Causes of Death and Total Population and followed for mortality from 1952 through 2006. Standardised mortality ratios (SMRs) were estimated using the Swedish male population as reference.
1841 observed deaths resulted in an SMR for all causes of deaths of 1.29 (95% CI 1.24 to 1.36). Mortality was significantly increased for all malignant tumours, oesophageal cancer, bowel cancer, liver cancer, lung cancer, alcoholism, ischaemic heart disease, non-malignant respiratory diseases, liver cirrhosis, external causes and suicides. The lung cancer SMR remained increased, although attenuated, after adjustment for group-level smoking data, SMR of 1.52 (95% CI 1.26 to 1.89). Duration of employment showed no consistent evidence of dose-response associations. Alcohol-related deaths (liver cirrhosis and alcoholism) were not increased among those employed >30 years. Mortality among those employed after 1950 was similar to that of the entire cohort.
Chimney sweeps are exposed to high levels of toxic substances in the occupation, but excess alcohol and smoking habits were also observed, and the results must be interpreted cautiously. However, group-level data on tobacco smoking indicated that the lung cancer excess only to some extent could be explained by smoking habits, and the increased mortality from oesophageal cancer and ischaemic heart disease among chimney sweeps employed >30 years is less likely to be caused by excess alcohol habits.

11 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: The quality of indoor and outdoor air is one of the most discussed topics nowadays, as it is an important parameter influencing human health. Exposure to various health–hazardous atmospheric pollutants may result in various adverse health effects. To understand the relationship between air quality and health, it is important to study pollutants that have the most hazardous effects on human health. In that regard, polycyclic aromatic hydrocarbons are one of the most important pollutants. Polycyclic aromatic hydrocarbons (PAHs) are the largest known group of carcinogens that are ubiquitously found in the environment (air, water, soils and sediments). The scientific evidence available up to this date indicates that exposure to PAHs in various occupational environments can lead to health burdens among exposed workers being considerably higher than those for general population. In particular, industrial processes that involve the pyrolysis or combustion of coal production and use of coal-derived products are the major sources of PAHs. Thus, this chapter is dedicated to occupational exposure to PAHs. A discussion on PAHs is given covering their major aspects. The work also focuses on exposures to PAHs in various PAH–related occupations and associated health effects.
    Air Pollution: Sources, Prevention and Health Effects, Edited by Rajat Sethi, 01/2013: chapter 13: pages 209-249; Nova Science Publishers., ISBN: 978-1-62417-746-0.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives: We examined cancer incidence in an expanded cohort of Swedish chimney sweeps. Methods: We added male chimney sweep trade union members (1981-2006) to an earlier cohort (employed 1918-1980) and linked them to nationwide registers of cancer, causes of deaths, and total population. The total cohort (n = 6320) was followed from 1958 through 2006. We estimated standardized incidence ratios (SIRs) using the male Swedish population as reference. We estimated exposure as years of employment and analyzed for exposure-response associations by Poisson regression. Results: A total of 813 primary cancers were observed versus 626 expected (SIR = 1.30; 95% confidence interval = 1.21, 1.39). As in a previous follow-up, SIRs were significantly increased for cancer of the esophagus, liver, lung, bladder, and all hematopoietic cancer. New findings included significantly elevated SIRs for cancer of the colon, pleura, adenocarcinoma of the lung, and at unspecified sites. Total cancer and bladder cancer demonstrated positive exposure-response associations. Conclusions: Exposure to soot and asbestos are likely causes of the observed cancer excesses, with contributions from adverse lifestyle factors. Preventive actions to control work exposures and promote healthier lifestyles are an important priority.
    American Journal of Public Health 01/2013; 103(9). DOI:10.2105/AJPH.2012.300860 · 4.55 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives: Previous studies of chimney sweeps have shown an excess mortality from cardiovascular diseases, although the extent of confounding from tobacco smoking is uncertain. The present study used referents of similar socioeconomic background as the chimney sweeps in order to reduce confounding, included both lethal and surviving cases of myocardial infarction, and investigated dose-response in terms of duration of employment. Methods: A cohort of 4436 male chimney sweeps was identified from nationwide trade union records from 1918 to 2006. Myocardial infarctions during 1991-2005 were identified from the Swedish nationwide register of first-time myocardial infarctions. Standardised incidence ratios (SIRs) were estimated using skilled manual workers in the service sector in Sweden to calculate expected numbers. Results: There was a strong and statistically significant excess of myocardial infarction among the chimney sweeps, SIR 1.39 (95% CI 1.24 to 1.55). The excess was observed among both short- and long-term employed. Conclusions: While the excess of myocardial infarction among the short-term employed may be due to tobacco and, possibly, alcohol use, it is likely that the excess noted among the long-term employed was caused by the high exposure to combustion products, particles or metals still occurring among chimney sweeps. Preventive measures to reduce hazardous occupational exposures as well as smoking and alcohol use among chimney sweeps are urgently needed.
    Occupational and environmental medicine 04/2013; 70(7). DOI:10.1136/oemed-2013-101371 · 3.27 Impact Factor
Show more

Similar Publications