Analysis and dissipation of the antiparasitic agent ivermectin in cattle dung under different field conditions.
Cattle treated with the veterinary parasiticide ivermectin fecally excrete residues. The authors report the exposition and dissipation characteristics of these residues in dung of ivermectin-treated cattle and in soil beneath this dung on pastures in Canada, France, Switzerland, and The Netherlands. Residues were quantified for dung collected from cattle after 3 d, 7 d, 14 d, and 28 d posttreatment and subsequently exposed in the field for up to 13 mo. The authors optimized a high-performance liquid chromatography-fluorescence detection method to detect ivermectin residues in dung and soil matrices. They showed that a solid phase extraction and purification step generally can be eliminated to reduce the time and cost of these analyses. They also found that the addition of water to relatively dry samples improves the extraction efficiency of residues. They then analyzed the field samples to document differences in ivermectin dissipation in cattle dung among sites, with 50% dissipation times of up to 32 d and 90% dissipation times >396 d. They further showed that the dissipation characteristics of residues are comparable between dung of ivermectin-treated cattle and dung to which ivermectin has been added directly. Lastly, they report the first use of a desorption electrospray ionization-high-resolution-mass spectrometric method to detect residues of metabolites in a dung matrix. Environ Toxicol Chem 2016;35:1924-1933. © 2016 SETAC.
Institute of Soil Science and Soil Conservation, Justus Liebig University, Giessen, Germany.
Manuel
M
Wohde
Evolutionary Biology & Environmental Studies, University of Zurich, Zurich, Switzerland.
Wolf U
WU
Blanckenhorn
Agriculture and Agri-Food Canada, Lethbridge, Alberta, Canada.
Kevin D
KD
Floate
Alterra, Wageningen University and Research Centre, Wageningen, The Netherlands.
Joost
J
Lahr
Centre for Evolutionary & Functional Ecology, Université Paul-Valéry, Montpellier, France.
Jean-Pierre
JP
Lumaret
ECT Oekotoxikologie, Flörsheim, Germany.
Jörg
J
Römbke
ECT Oekotoxikologie, Flörsheim, Germany.
Adam
A
Scheffczyk
Centre for Evolutionary & Functional Ecology, Université Paul-Valéry, Montpellier, France.
Thomas
T
Tixier
Institute of Soil Science and Soil Conservation, Justus Liebig University, Giessen, Germany.
Rolf-Alexander
RA
Düring
D000818:Animals; D000977:Antiparasitic Agents / Q000032:analysis*; D002170:Canada; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004784:Environmental Monitoring / Q000379:methods*; D005243:Feces / Q000737:chemistry*; D005602:France; D007559:Ivermectin / Q000032:analysis*; D009426:Netherlands; D018570:Risk Assessment; D012987:Soil / Q000737:chemistry*; D013557:Switzerland
D000977:Antiparasitic Agents; D012987:Soil; D007559:Ivermectin
Cattle dung; Environmental chemistry; Fate and transport; Ivermectin; Pharmaceutical