Background: Up to now potential health effects of environmental exposure to intensive livestock production facilities have not been thoroughly studied. The aim of the Lower Saxony Lung Study (NiLS) was to assess the prevalence of respiratory symptoms and disease in an area with intensive animal production facilities taking into account environmental exposure to emissions from these large-scale farms.
Methods: All 10 864 inhabitants (age 18 to 44 years) of four towns with a large number of intensive animal production facilities in the area were invited to answer a mail-in questionnaire. Of these, 6416 subjects were randomly selected for the clinical part of the study (specific IgE, lung function measurements, bronchial provocation with methacholine). Overall, 6937 subjects answered the questionnaire (68 %), 60 % took part in the clinical tests.
Results: The prevalence of allergic disease in the study population was lower than in urban citizens. Subjects with more than 12 animal houses within 500 m of their home had an increased odds ratio for wheezing without a cold (odds ratio 2.7; 95 % confidence interval 1.4 - 5.4). They also showed a significantly decreased FEV (1) (mean 0.26 l; 0.04 l - 0.48 l) as well as a trend for a lower Tiffeneau-Index.
Conclusions: In result, a large number of intensive animal production facilities might be associated with decreased lung function results in the immediate neighbours. Further studies are necessary to confirm our findings.