Abstract
BACKGROUND: Longitudinal studies investigating air pollution from livestock farms and respiratory health effects in neighboring residents are lacking. The aim of this study was to assess the relationship between residential livestock farm exposures and lung function decline over a 7-year period in people living in livestock-dense rural areas in the Netherlands. METHODS: Spirometry was performed in 2014/2015 and 2021/2022 for 847 adults (28-80 years of age at follow-up). We analyzed the annual rate of change in forced expiratory volume in 1 second (FEV(1)), forced vital capacity (FVC), tiffeneau index (FEV(1)/FVC) , peak expiratory flow, and maximal mid-expiratory flow in relation to long-term exposure to livestock farming-emitted endotoxin and particulate matter <10 µm (PM(10)) at the home address, which was predicted by dispersion modeling at baseline. Data analysis was performed using generalized additive models with nonlinear terms for exposure, adjusting for potential confounders. RESULTS: No associations were identified between residential exposure to livestock-related endotoxin or PM(10) and the annual rate of change in lung function (P > 0.05). Adjusted models showed that participants with a farm childhood had larger annual decreases in FEV(1) (-5.63 ml/year, P = 0.018) and maximal mid-expiratory flow (-11.15 ml/second per year, P = 0.032), compared with those without a farm childhood. However, average baseline spirometry was higher in participants with a farm childhood compared with those without. CONCLUSION: Our longitudinal study did not find evidence for a relationship between air pollution from livestock farms and lung function decline in neighboring residents. Longitudinal studies with a greater number of observations across the life course are needed to gain deeper insights into lung function trajectories and to assess the impact of livestock-related air pollution in rural populations.