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Abstract: Veterinary antibiotics reach the soil environment by manure application, where they accumulate or are prone to vertical translocation. We assumed that a high pH value at slightly calcareous soil properties should retain tetracyclines and fluoroquinolones even at high manure loads, whereas it should facilitate leaching of sulfonamides. Hence, we investigated the transport of manure-added antibiotics in a soil developed from calcareous parent material on a farm in peri-urban Beijing, China. Leachate was collected from zero-tension samplers, installed at 40cm depth under undisturbed soil, which was treated according to (i) routine farm practice and (ii) worst-case conditions (high antibiotic concentrations, irrigation imitating heavy rainfall). Additionally, the soil depth distribution of pharmaceuticals at the end of the leaching experiment was analysed. Under routine farm practice, sulfamethazine was repeatedly detected in the leachate with a maximum concentration of 0.12μgL−1. All applied substances were still detected in soil after 53days, suggesting that there was no overall rapid and complete dissipation. Worst-case conditions enhanced vertical translocation; all leachate samples contained sulfonamides (up to 653μgL−1 sulfamethazine), and even tetracyclines were found in the leachate once, with doxycycline reaching the highest concentration (0.19μgL−1). The concentrated simultaneous occurrence of sulfonamides with the bromide tracer in leachate samples pointed to preferential flow as underlying transport process. The high pH values did not prevent the single leaching event for tetracyclines and hardly affected overall leaching behaviour. The applied fluoroquinolones were not significantly translocated below 4cm depth, irrespective of irrigation and high manure addition. [Copyright &y& Elsevier]

Copper is used as a growth promoter in animal husbandry, resulting in high Cu concentrations in animal manure. We tested whether Cu would be mobilized in soils receiving excessive loads of manure, both from recently added and from aged fractions. To discriminate between these Cu sources, manure was labeled with 65Cu. After soil application of 0, 15, and 30 Mg manure ha-1, leachate was collected in free-draining lysimeters (40 cm depth) under undisturbed soil over a 53 day period. Determining the total amounts of Cu and the fractions of 65Cu in leachate and the soil profile enabled us to trace the translocation of Cu derived from labeled manure. More than 84% of the applied Cu was retained in the top 2 cm of soil. Less than 0.01% of the applied Cu was detected overall in the leachate. Of this amount, however, 38% (±8.9 SE) was leached within 8 days after application. The total Cu concentration in leachates (32-164 μg L-1) frequently exceeded the Chinese groundwater quality standard of 50 μg L-1. The added 65Cu, however, accounted for less than 3.6% of the total Cu leaching load, suggesting that Cu from older sources and/or geological background controls contamination, regardless of current land management. [ABSTRACT FROM AUTHOR]