Spatial analysis of health effects of large industrial incinerators in England, 1998-2008: a study using matched case-control areas

Abstract

Objectives: To assess whether residential proximity to industrial incinerators in England is associated with increased risk of cancer incidence and mortality.

Design: Retrospective study using matched case-control areas.

Setting: Five circular regions of radius 10 km near industrial incinerators in England (case regions) and five matched control regions, 1998-2008.

Participants: All cases of diseases of interest within the circular areas.

Primary and secondary outcome measures: Counts of childhood cancer incidence (<15 years); childhood leukaemia incidence (<15 years); leukaemia incidence; liver cancer incidence; lung cancer incidence; non-Hodgkin's lymphoma incidence; all-cause mortality; infant mortality (<1 year) and liver cancer mortality.

Results: The estimated relative risks for case circles versus control circles for the nine outcomes considered range from 0.94 to 1.14, and show neither elevated risk in case circles compared to control areas nor elevated risk with proximity to incinerators within case circles.

Conclusions: This study applies statistical methods for analysing spatially referenced health outcome data in regions with a hypothesised exposure relative to matched regions with no such exposure. There is no evidence of elevated risk of cancer incidence or mortality in the vicinity of large industrial incinerators in England.

Figure 1

Locations of case and control regions.

Figure 2

Estimated standardised mortality/incidence ratios (SMRs/SIRs) for each health outcome with respect to distance to the centre of the circle (case circles only). Line numbers correspond to case circles shown in figure 1. Vertical axis is plotted on logarithmic scale.

Figure 3

Estimated standardised mortality/incidence ratios (SMRs/SIRs) over time for each health outcome, averaged across case and control circles. Vertical axis is plotted on the logarithmic scale.