Dissipation of oxytetracycline, chlortetracycline, tetracycline and doxycycline using HPLC-UV and LC/MS/MS under aquatic semi-field microcosm conditions.
A mixture of four tetracyclines; oxytetracycline (OTC), chlortetracycline (CTC), tetracycline (TC), and doxycycline (DC) was applied in fifteen 12000l outdoor microcosms at four treatment levels plus controls each with three replicates (n = 3). The dissipation times of parent compounds were monitored and half-lives (DT50) of 1-4 days, depending on treatment level were recorded. This is in accordance with half-lives from previous findings in bench-top experiments. Parent compound DT50, were determined using HPLC-UV. Furthermore, the samples were analyzed for ten different tetracycline products using LC/MS/MS. Two products were found for chlortetracycline; 4-epi-anh-chlortetracyline and the iso-chlortetracycline. Iso-forms were only found for CTC and only at the highest treatment (300 microg l(-1)). The half-lives, trajectories, and relative amounts of the products were analogous for all four tetracyclines. DT50 for products were less than 1.2 days. Formation of 4-epi-anh-tetracyclines, occurred at neutral to weak alkaline conditions.
Sanderson
Hans
H
University of Guelph, Centre for Toxicology, Bovey Building, Guelph, Ont., N1G 2W1, Canada. hsanderson@sdahq.org
Ingerslev
Flemming
F
Brain
Richard A
RA
Halling-Sørensen
Bent
B
Bestari
Jim K
JK
Wilson
Christian J
CJ
Johnson
David J
DJ
Solomon
Keith R
KR
D002851:Chromatography, High Pressure Liquid; D004784:Environmental Monitoring; D006207:Half-Life; D013754:Tetracyclines / Q000032:analysis* / Q000737:chemistry*; D014466:Ultraviolet Rays; D014873:Water Pollutants / Q000032:analysis*
D013754:Tetracyclines; D014873:Water Pollutants