Determination and fate of oxytetracycline and related compounds in oxytetracycline production wastewater and the receiving river.
This study investigated the occurrence and fate of oxytetracycline (OTC) and its related substances, 4-epi-oxytetracycline (EOTC), alpha-apo-oxytetracycline (alpha-apo-OTC), and beta-apo-oxytetracycline (beta-apo-OTC), in a wastewater treatment plant (WWTP) treating OTC production wastewater and a river receiving the effluent from the WWTP using liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS). The percent removal of OTC in the WWTP was 38.0 +/- 10.5%, and the concentration of OTC was still up to 19.5 +/- 2.9 mg/L in the treated outflow. The concentration slightly decreased along the river, from 641 +/- 118 microg/L at site R2 (discharging point) to 377 +/- 142 microg/L at site R4 ( approximately 20 km from site R2), which was still higher than the minimal inhibition concentration of OTC reported ( approximately 250 microg/L). On the other hand, the total amount of its related substances in the treated effluent was less than 5% of OTC. Concentrations of alpha-apo-OTC and beta-apo-OTC increased along the river, from 5.76 +/- 0.63 and 2.08 +/- 0.30 microg/L at site R2 to 11.9 +/- 4.9 and 12.0 +/- 4.6 microg/L at R4, respectively, although EOTC decreased from 31.5 +/- 3.8 to 12.9 +/- 1.1 microg/L, respectively. The mean concentration of beta-apo-OTC in river sediments was 20.8 +/- 7.8 mg/kg, and its ratio to OTC was approximately 0.11, nearly twice the ratio of alpha-apo-OTC and EOTC to OTC (0.058 +/- 0.014 and 0.061 +/- 0.015, respectively).
Li
Dong
D
State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
Yang
Min
M
Hu
Jianying
J
Ren
Liren
L
Zhang
Yu
Y
Li
Kuiziao
K
D002853:Chromatography, Liquid; D007220:Industrial Waste / Q000032:analysis*; D010118:Oxytetracycline / Q000032:analysis*; D045483:Rivers; D021241:Spectrometry, Mass, Electrospray Ionization; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000032:analysis*
D007220:Industrial Waste; D014874:Water Pollutants, Chemical; D010118:Oxytetracycline