A NEW study has uncovered significant associations between the use of certain pesticides and an elevated risk of rheumatoid arthritis (RA) among older farmers. The research, part of the Agricultural Health Study, analysed data from 22,642 licensed pesticide applicators aged 67 and older from North Carolina and Iowa. It offers critical insights into how specific chemicals commonly used in farming may contribute to the development of RA.
The study identified 161 new RA cases among participants between 1999 and 2016. Analysis revealed a higher risk of RA linked to lifetime use of nine pesticides, including four insecticides (malathion, phorate, carbaryl, carbofuran), four herbicides (alachlor, metolachlor, S-Ethyl dipropylthiocarbamate, metribuzin), and one fungicide (benomyl). Notably, the use of malathion, a widely approved insecticide, was associated with a 77% increased risk of RA, while exposure to carbaryl showed a 65% higher risk. Some of these pesticides are still in use today across agricultural, public health, and residential settings.
The study also found evidence of exposure-response relationships for malathion and carbofuran, meaning that increased lifetime exposure to these chemicals corresponded to a higher risk of developing RA. These findings suggest that the intensity and frequency of pesticide use are critical factors in the potential development of RA among farmers.
While previous research has suggested a general link between farming and RA, this study is among the first to pinpoint specific pesticides associated with heightened risk. The findings raise concerns about the ongoing use of these chemicals and underscore the importance of protective measures for individuals in agricultural occupations.
Healthcare professionals are encouraged to consider pesticide exposure when assessing RA risk in farming populations. The study also calls for policymakers to review current pesticide approvals, particularly for those linked to chronic health conditions, to ensure safety for both agricultural workers and the general public.
Aleksandra Zurowska, EMJ
Reference
Parks CG et al. Associations between pesticide use and rheumatoid arthritis among older farmers in the Agricultural Health Study. Sci Rep. 2024;DOI: 10.1038/s41598-024-76179-2.
