There is some consensus that the risk of lung cancer posed by asbestos dust exposure is usually of the order RR = 5, that from smoking, RR= 10 and from the combination, RR = 50. This review paper suggests an alternative view, that the asbestos related risk is actually reduced by co-smoking.
Evidence from:
FD Liddell. Ann Occup Hyg. Jul (2001) Vol. 45(5) p 341-56.
The author introduces the term: relative asbestos effect, to account for the competition between smoke and asbestos to be the first to actually cause the cancer.
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