Natural estrogen emissions to subsurface tile drains from experimental grassland fields in Switzerland after application of livestock slurries and free compounds

Natural estrogens are present in high concentrations livestock slurries, which often applied to agricultural fields large quantities. As such, the export of slurry-derived natural from tile-drained is a potential source for estrogenic pollution surface waters. Yet despite abundance Central Europe, receiving slurries rarely studied this region. In an effort fill knowledge gap, here we Swiss experimental form cattle slurry, pig slurry or dissolved water, and quantified them flow-proportionally collected drainage water over 18 months. After applications, concentration maxima 73, 8, 37, 60 ng L?1 17?-estradiol (E2?), 17?-estradiol (E2?), estrone (E1), estriol (E3), respectively, were observed shortly after rain events. The exported fractions individual tile drains on average 0.26% (ranging 0.08 0.41%) cattle, 0.18% (0.03–0.40%) applications. Such numbers higher than expected leaching based substance properties, comparable those more mobile micropollutants previously same fields. mainly through preferential flow. Exported lower when aqueous solution pointing particle-facilitated transport slurry. Switzerland, estimated 6.3, 0.6, 7.4, 7.7 g E2?, E2?, E1, E3, area per year contribute little total estrogen load received by However, applications highly drained catchments, emissions can cause short term (i.e. less 1 week) exposure nearby streams.