The urban/rural divide in head and neck cancer--the effect of atmospheric pollution.

Inter-district variations in the incidence of head and neck squamous carcinoma in the period 1978-1987 have been identified from records at the West Midlands Cancer Registry, England. Analysis of the records reflect the national and international trend of higher urban cancer rates compared with neighbouring rural communities. Atmospheric pollution data (mean sulphur dioxide and smoke concentrations) from a national survey are positively correlated with squamous cancer of the larynx and pharynx. The correlation is most significant between laryngeal cancer rates and atmospheric sulphur dioxide levels. The periods 1950-1970 and 1970-1990 have been analysed separately to reflect the reduction in atmospheric pollution that has occurred over these years and thus avoid missing a latent effect that this might have on cancer rates.