Processes strongly associated with occupational lung cancer: aluminum production, coke production, coal gasification, underground hematite mining (radon), iron and steel founding, nickel refining (nickel oxides and sulfides), painters, and passive smoking. Agents (IARC Group 1) strongly associated with occupational lung cancer: arsenic compounds, hexavalent chromium compounds, asbestos, beryllium, cadmium compounds, ionizing radiation, crystalline silica, soots, and talc containing asbestiform fibers. Bis(chloromethyl)ether and chloromethyl methyl ether (technical grade) were strongly associated with lung (oat cell) cancer. [Siemiatycki, p. 334] "There is sufficient evidence in humans for the carcinogenicity of coal-tar pitch as encountered in paving and roofing. Coal-tar pitch as encountered in paving and roofing causes cancer of the lung." [IARC 2012: Coal-tar pitch] Ionizing radiation was strongly associated with lung cancer in studies of Japanese A-bomb survivors, patients treated with radiation for Hodgkin's disease, underground miners, and Mayak workers with heavy exposure to plutonium. Negative associations were found in studies of radiologists, nuclear workers, uranium workers, and populations exposed to background radiation. [Boice, p. 261] "Workers with heavy exposure to asbestos have a similar risk of lung cancer as persons with low or no exposure 20 years after the exposure has ended." [
PMID 25479300]