Determination of Oxytetracycline Residues in Matrixes from a Freshwater Recirculating Aquaculture System

Abstract

This paper describes related procedures to determine the amount of oxytetracycline (OTC) present in trout tissue (muscle with skin attached), biofilter sand, sediment, and tank water from a recirculating aquaculture system. OTC was extracted from the matrixes by different techniques, depending on complexity of the matrix and desired OTC detection level in that matrix. Listed in order of increasing complexity, OTC was extracted from tank water by dilution with acidic buffer containing ethylenediaminetetraacetic acid (EDTA); from biofilter sand by shaking with 0.1N HCl; from sediment by homogenization and shaking with buffer/EDTA; and from ground trout by homogenization and shaking with buffer/EDTA (twice), with further cleanup and concentration of the extract on a polymeric solid-phase extraction cartridge. The 4 procedures all used the same reversed-phase gradient chromatography on a polymeric column with UV detection at 350 nm. The lower limit of detection (estimated) and upper limit of validation for each of these 4 matrixes were 0.04–4.0 μg/g (ppm; trout), 0.03–20 ppm (biofilter sand), 1–6000 ppm (sediment), and 0.003–10 ppm (water). Recoveries ranged from 82 to 108%, with relative standard deviation <20% over the applicable concentration ranges. These procedures were used to monitor OTC residues resulting from medicated feed administered to rainbow trout in a recirculating aquaculture system.

Persistent Oxytetracycline Exposure Induces an Inflammatory Process That Improves Regenerative Capacity in Zebrafish Larvae

“…Due to approximately 70 to 80% of the antibiotics administered are released into the aquatic environment, these chemicals must be considered potential environmental micropollutants [2] . Unfortunately, there are no reports about this problem and only limited information is available regarding the presence of antibiotics in the sediment surrounding the fish farms in a few countries [3] – [6] .…”

Temporal and Spatial Trends in the Occurrence of Human and Veterinary Antibiotics in Aqueous and River Sediment Matrices

“…Understanding the antibiotic occurrence in the different environmental compartments (e.g., surface water, sediments, and soil) could be used to evaluate the transport and ultimate fate of animal used antibiotics via surface runoff or leaching through the subsurface ( , ). Another pathway of antibiotic release to the environment is aquaculture and the occurrence of antibiotic residuals has been reported from these operations ( − ).…”

Nutrients Removal from Aquaculture Wastewater by Biofilter/Antibiotic-Resistant Bacteria Systems

“…In this paper, the bacterial biofilm retention efficiency for the six types of biofilters was evaluated gravimetrically by determining the amount of biofilm deposited on the support, both in the absence and presence of OTC (Table 3). OTC is a common antibiotic in aquaculture [47] and potentially has a harmful influence on bacterial species development with water purification potential. Therefore, bacterial strain choice with intrinsic resistance to OTC is essential for developing treatment solutions based on them.…”