Air Pollution from Livestock Farms is Associated with Airway Obstruction in Neighboring Residents

RATIONALE: Livestock farm emissions may not only affect respiratory health of farmers but also of neighboring residents. OBJECTIVES: To explore associations between both spatial and temporal variation in pollutant emissions from livestock farms and lung function in a general, non-farming, rural population in the Netherlands. METHODS: We conducted a cross-sectional study in 2,308 adults (age 20-72 years). A pulmonary function test was performed measuring pre- and post-bronchodilator FEV1, FVC, FEV1/FVC and MMEF. Spatial exposure was assessed as 1) number of farms within 500 m and 1,000 m of the home, 2) distance to the nearest farm, and 3) modelled annual average fine dust emissions from farms within 500 m and 1,000 m of the home address. Temporal exposure was assessed as week-average ambient PM10 and ammonia (NH3) concentrations prior to lung function measurements. Data were analyzed with generalized additive models (smoothing). RESULTS: A negative association was found between the number of livestock farms within a 1,000 m buffer from the home address and MMEF, which was more pronounced in non-atopic participants. No associations were found with other spatial exposure variables. Week-average PM10 and NH3 levels were negatively associated with FEV1, FEV1/FVC and MMEF. In a two-pollutant model, only NH3 remained associated. A 25 µg/m3 increase in NH3 was associated with a 2.22% lower FEV1 (95%CI -3.69 to -0.74), FEV1 /FVC: -1.12% (-1.96 to -0.28) and MMEF: -5.67% (-8.80 to -2.55). CONCLUSION: Both spatial and temporal variation in livestock air pollution emissions are associated with lung function deficits in non-farming residents