[Occupational hazardous substance exposure and nutrition. Risk factors for mouth, pharyngeal and laryngeal...

A case-control study was conducted to investigate occupational and other risk factors for squamous cell carcinoma of the oral cavity, the pharynx and the larynx. The study included 209 male cancer patients and 110 male control persons without known malignant disease, matched for age, alcohol consumption and tobacco consumption.

Cases and controls were interviewed using a standardized questionnaire which has been used before in the Heidelberg case-control studies.

The educational level in the cancer group was significantly lower (p < 0.001). 17.2% of the cancer patients and 7.3% of the control persons had not completed their professional training. The percentage of so-called "blue-collar workers" was significantly higher in the cancer group (20.9% vs. 7.3%; p < 0.002). An increased cancer risk was observed for workers exposed to asbestos (OR = 8.7; p = 0.004) and cement dust (OR = 12.9; p < 0.001). A frequent consumption of various vegetable food like carrots (OR = 0.17; p < 0.001), fruits (OR = 0.38; p < 0.001) or green salad (OR = 0.25; p < 0.001) was associated with a significant reduction of cancer risk.