Residential proximity to crops and agricultural pesticide use and cause-specific mortality: A prospective census-based cohort study in the Netherlands

Background There is continued concern about residential proximity to agricultural pesticide use and possible adverse health effects. Studies on this subject have been scarce with inconsistent results. We explored associations between residential proximity to specific crops, pesticide use and cause-specific mortality in a prospective census-based cohort study in The Netherlands. Methods Selecting inhabitants aged >30 living in less urbanized areas, at the same address for nine years up to baseline (2004) from a national register-based cohort, we followed ~3.1 million individuals for cause-specific mortality until 2012. We estimated the area of specific crop groups cultivated within buffers of 50 m, 100 m and 250 m around each individual's residence and the amount of fungicides, herbicides and insecticides used within the same buffers for the period 1995–2003. The association between these exposure proxies and 25 primary causes of death was investigated using Cox proportional hazards regression, adjusting for individual and area-level confounders. Results Residential proximity to crops was associated with decreased mortality risks overall. In contrast to the overall trend an increased risk was observed for chronic lower respiratory diseases and proximity to maize cultivation. We found no evidence of an association between the amount of pesticides used and cause-specific mortality. Conclusions In a large prospective census-based cohort study in The Netherlands we found evidence of an increased risk of chronic lower respiratory diseases in relation to maize cultivation which was not reflected in general pesticide use, hinting to specific pesticides or practices in maize cultivation that may lead to the observed increased risk.