Veterinary pharmaceuticals and antibiotics in manure and slurry and their fate in amended agricultural soils: Findings from an experimental field site (Baix Empordà, NE Catalonia)

Abstract

The fate and transport of 34 veterinary pharmaceuticals (PhACs) is investigated in swine slurry and dairy cattle manure-amended agricultural soils, from an experimental field site, by using both analytical and modelled data. Potential differences on PhACs fate, attributed to the application of distinct swine slurry fractions (total, solid, and liquid), are herein assessed for the first time. Surface and deep soil layers, up to a depth of 120 cm, were analyzed at different periods after an annual fertilization event. Using input data representing typical agricultural soil conditions and the PhACs concentration measured in organic fertilizers the transport of these pollutants was modelled for a period of 10 years, including the monitored annual fertilization event. Fluoroquinolone, tetracycline and pleuromutilin antibiotics, together with anti-helmintics and analgesic and anti-inflammatories, were detected in manure-amended soils, at average concentrations ranging from 0.078 to 150 μg/kg dw in surface layers, with the highest levels found in the fields fertilized with the swine slurry solid fraction. Even though severe disagreements were observed between experimental and simulated PhACs concentrations along the soil column, both approaches pointed out that target compounds strongly adsorb onto surface layers, showing limited mobility along the soil profile. Thus, repeated manure and slurry fertilizations will contribute in building up persistent PhACs residues in the uppermost layers of the soil, while leaching will be a minor process governing their fate towards the subsurface. The ecotoxicological risks posed by the occurrence of PhACs in soils were estimated to be low for terrestrial organisms. Nevertheless the antibiotic enrofloxacin showed some potential to induce negative effects to crops

This work has been supported by the Secretary of Universities and Research of the Counsel of Economy and Knowledge of the Catalan Government (AGAUR) and the COFUND Program of the Marie Curie Actions of the 7th R&D EU Program. It has also been supported by the projects PERSIST (EU Water Joint Programming Initiative, JPIW2013-118) and REMEDIATION (CGL2014-57215-C4-2-R), and the University of Girona funds MPCUdG2016/061. Authors also acknowledge the support from the Economy and Knowledge Department of the Catalan Government through Consolidated Research Group (ICRA-ENV 2017 SGR 1124)