Geography of non-melanoma skin cancer and ecological associations with environmental risk factors in England

Abstract

Background: This study investigates the geography of non-melanoma skin cancer (NMSC) in England, and ecological associations with three widespread environmental hazards: radon, arsenic and ultraviolet radiation from the sun.

Methods: Age-/sex-standardised registration rates of NMSC were mapped for local authority (LA) areas (n=326), along with geographical data on bright sunshine, household radon and arsenic. Associations between NMSC and environmental variables, adjusted for socio-economic confounders, were investigated.

Results: There was a substantial geographical variation in NMSC rates across English local authorities and between cancer registration regions. Forty percent of variance in rates was at registry region level and 60% at LA level. No association was observed between environmental arsenic and NMSC rates. Rates were associated with area-mean bright sunshine hours. An association with area-mean radon concentration was suggested, although the strength of statistical evidence was sensitive to model specification.

Conclusion: The significant geographical variation across England in NMSC registration rate is likely to be partly, but not wholly, explained by registry differences. Findings tentatively support suggestions that environmental radon may be a risk factor for NMSC. Although NMSC is rarely fatal, it has significant implications for individuals and health services, and further research into NMSC geographical and environmental risk factors is warranted.

Figure 1

Histograms of the distribution of NMSC directly standardised registration rates (DSR) – registrations per 1 00 000 population per year, 2006–2008 across (A) all 311 study local authorities (LAs) and (B) 255 LAs, excluding those within Thames regional cancer registry.

Figure 2

Non-melanoma skin cancer directly age-/sex-standardised registration rates, registrations per 1 00 000 population per year, 2006–2008, English local authorities (LAs). Rates for Thames region excluded as described in the text. Cancer registry region names are labelled.