The combined effects of smoking and occupational or urban factors in relation to lung cancer

Our plain-English summary of The combined effects of smoking and occupational or urban factors in relation to lung cancer, by R.E. Waller (The Annals of Occupational Hygiene, 1972).

The study

• Author: R.E. Waller
• Journal: The Annals of Occupational Hygiene
• Published: 1972;15(1):67-73
• Cited by: 6 articles, as counted by NIH iCite
• Read it: PubMed · Publisher
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 003969).

Abstract

In this brief review, some of the published work on lung cancer mortality has been considered in relation to possible "interactions" between smoking and other factors. Although there is evidence to suggest that smoking enhances the lung cancer risk in certain occupational groups, studies on general populations show that the effect of smoking is large compared with that of "urban" factors and there is no indication of any interaction between smoking and air pollution.

PubMed has no abstract for this study. This is the authors' abstract, copied from the article.

In plain English

This 1972 article was a brief review of some published studies on lung cancer deaths. It asked whether smoking 'interacts' with job exposures or with 'urban' factors such as air pollution. It did not report new data of its own. One of the studies reviewed, by Selikoff and colleagues, followed insulation workers in New York and New Jersey who could be exposed to asbestos fibres. Between 1963 and 1970 that group had 33 lung cancer deaths among 283 smokers and one among 87 non-smokers. Those authors suggested an interaction between smoking and asbestos. This author noted that the small non-smoking group made its true rate difficult to establish at that stage. The review also covered studies of uranium, nickel and gas workers. In the general-population studies reviewed, lung cancer death rates rose roughly 10- to 20-fold from non-smokers to the heaviest smokers, while differences by area of residence were smaller and less consistent. The author concluded that there is evidence suggesting smoking enhances lung cancer risk in certain occupational groups, but that air pollution, alone or combined with smoking, may be only a minor factor.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Brief narrative review of published studies (no new data)
• Who was studied: Published studies reviewed: insulation workers in New York and New Jersey (Selikoff et al.), uranium workers in the United States, nickel workers, gas workers, and general-population surveys in North Wales and North West England, Northern Ireland, several international cities, and male doctors in the United Kingdom
• Exposure: Cigarette smoking in combination with occupational exposures (asbestos fibres in insulation work, radiation in uranium work, the nickel refining process, tarry fumes in gas retort houses) or with urban air pollution
• Main results:
  • In the reviewed study of insulation workers (Selikoff et al., 1968), there were 33 lung cancer deaths among 283 smokers but only one among 87 non-smokers between 1963 and 1970
  • The Selikoff authors suggested an interaction between smoking and asbestos, with a lung cancer death rate difference between smokers and non-smokers larger than expected from adding the two effects. This author noted that the small non-smoker group made the true rate difficult to establish at that stage.
  • In the reviewed study of gas workers, the lung cancer death rate of retort house workers was about 150 per cent of that expected in the general population. The author judged this moderate increase did not suggest a multiplicative effect of smoking and occupational exposure.
  • In the Stocks (1958) survey of North Wales and North West England, lung cancer mortality rose about 10-fold from non-smokers to the highest smoking category. Variation by area was less marked and less consistent, and among the heaviest smokers there was no difference by area of residence.
  • In the Northern Ireland survey (Wicken, 1966), lung cancer mortality rose 10- to 20-fold from non-smokers to the heaviest smokers. Apart from low rates in truly rural areas, variation by area of residence was small and inconsistent.
  • In the study of UK doctors (Doll and Hill, 1964), there was only a small difference in lung cancer death rates between doctors living in urban and rural areas, compared with a 10- to 20-fold difference between non-smokers and heavy cigarette smokers.
• The authors' conclusion: The author concluded that there is evidence suggesting smoking enhances lung cancer risk in certain occupational groups. The author also concluded that air pollution, alone or combined with smoking, may be only a minor factor in lung cancer, with no indication of an interaction between smoking and air pollution.
• Limitations the authors state:
  • Many occupational studies collected little information on smoking habits, and retrospective studies often had no smoking data for earlier periods.
  • In the uranium workers study, the non-smoking group was small (two lung cancer deaths), so the choice between additive and multiplicative models was uncertain.
  • Smoke concentrations had changed rapidly over the previous 10 to 15 years, making relevant exposures extremely difficult to assess.
  • The doctors' study population may not be the best for studying factors other than smoking.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Lung cancer.

Medical terms in this study, explained in our Lexicon: Lung Cancer.

Related studies

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• Combined effect of asbestos and smoking on mortality from lung cancer and mesothelioma in factory workers — G. Berry, M.L. Newhouse, et al. (1985)
• Cancer incidence in urban, rural, and densely populated districts close to core cities in Bavaria, Germany — M. Radespiel-Tröger, K. Geiss, et al. (2018)
• Alcohol, smoking, and occupational factors in cancer of the larynx: a case-control study — W. Ahrens, K.H. Jöckel, et al. (1991)
• Combined effect of asbestos exposure and smoking on mortality from lung cancer in factory workers — G. Berry, M.L. Newhouse, et al. (1972)
• Combined effect of asbestos exposure and tobacco smoking on Finnish anthophyllite miners and millers — L.O. Meurman, R. Kiviluoto, et al. (1979)

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