Historical cancer incidence and mortality assessment in an Illinois community proximal to a former manufactured gas plant

OBJECTIVES Concern has been raised that the occurrence of cancer may be increased in neighbourhoods around a former manufactured gas plant in Champaign, Illinois, USA. Thus, we compared historical rates of cancer in this area to comparison communities as well as with nationally standardised rates. DESIGN Retrospective population-based community cancer assessment during 1990-2010. SETTING Champaign County, Illinois, USA, and zip codes encompassing the location of the former manufactured gas plant to counties that were similar demographically. PARTICIPANTS Residents of the counties and zip codes studied between 1990 and 2010. MAIN OUTCOME MEASURES The relative risk (RR) and 95% CI were used to compare cancer incidence and mortality in the areas near the gas compression site to the comparison counties. Standardised incidence ratios (SIRs) were calculated to compare rates in the areas near the gas compression site to expected rates based on overall US cancer rates. RESULTS Total cancer mortality (RR=0.91, 95% CI 0.88 to 0.94) and incidence (RR=0.95, 95% CI 0.94 to 0.97) were reduced significantly in Champaign County versus the comparison counties. Similarly, a reduced rate of total cancer was observed in analyses by zip code (proximal to the former gas plant) when compared with either similar counties (RR=0.89, 95% CI 0.86 to 0.93) or national standardised rates of cancer (SIR=0.88, 95% CI 0.85 to 0.91). CONCLUSIONS This historical cancer assessment did not find an increased risk of total cancer or specific cancer types in communities near a former manufactured gas plant site.