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Marker residue depletion from the skin-on fillet tissue of rainbow trout exposed to AQUI S 20E: Data


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Jeff Meinertz, and Theresa Schreier, 20150929, Marker residue depletion from the skin-on fillet tissue of rainbow trout exposed to AQUI S 20E: Data: USGS: La Crosse, WI,


Among the data required by the U.S. Food and Drug Administration (FDA) for approval of an aquaculture drug are the data that characterize the depletion of a drugs marker residue from the edible fillet tissue of fish after exposure. Eugenol is the marker residue for AQUI-S 20E, a product proposed for use as a sedative for fish.Rainbow trout (Onchorynchus mykiss; a representative cold water fish species) was exposed to AQUI-S 20E in water at a temperature of 9 C, a temperature that is representative of the lower range of temperatures where rainbow trout would be sedated. Eighty fish were exposed to a nominal AQUI-S 20E concentration of 100 mg/L for 60 min. Groups of 16 fish were sampled immediately after 60 min of exposure (the 0 min [...]


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Jeff Meinertz
Metadata Contact :
Theresa M Schreier

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Concentration.csv 2.15 KB
Tissue.csv 2 KB
WQ.csv 424 Bytes


There is a critical need in U.S. public aquaculture and fishery management programs for the use of an immediate-release sedative, i.e., a compound that would safely and effectively sedate fish allowing for their release immediately after regaining normal swimming activity. An immediate-release sedative could be used during any field procedures involving the handling of fish (e.g., spawning and tagging). Such a sedative would have applications for nearly all freshwater fish species.Currently, Finquel (tricane methanesulphonate or MS-222) is the only fish sedative approved by the FDA. Use of this sedative is constrained by a 21-day withdrawal period, meaning fish exposed to MS-222 cannot be made available for human consumption for at least 21 days following exposure. This restriction was established by the FDA because of a lack of mammalian toxicological information concerning MS-222 residues residing in the fillet tissue after an exposure. The 21-day withdrawal period was established to allow the MS-222 residues to deplete from the fish, ensuring the fillet tissue could be safely consumed by humans. AQUI-S 20E (active ingredient and marker residue, eugenol; AQUI-S New Zealand Ltd., Lower Hut, New Zealand) is being pursued for U.S. approval as an immediate-release sedative for fish. As part of the approval process, a marker residue depletion study was needed to characterize the depletion of AQUI-S 20E residues in fillet tissue. Characterizing depletion of the marker residue will allow the FDA to establish a withdrawal time for AQUI-S 20E, ensuring that all AQUI-S 20E residues reach safe concentrations before fish become available for human consumption. When the potential exists for a drug to be used in a relatively wide range of water temperatures, depletion of the drug from the edible tissues of exposed fish should be determined at several temperatures or at the lower limit of the temperature range where the drug would be used. In this case, fish were exposed to AQUI-S 20E in water at a temperature of 9 C, a temperature that is representative of the lower range of water temperatures where fish would be sedated for management purposes. Rainbow trout served as the test species. Rainbow trout, a representative of cold water fish species, are commonly cultured, managed, and consumed throughout the U.S.An AQUI-S 20E total residue depletion study was completed at the Upper Midwest Environmental Sciences Center (UMESC; Meinertz et al. 2014b). Based on data from that study, the FDA declared that eugenol was the marker residue for AQUI-S 20E. Because of the lack of information concerning eugenol concentrations in freshwater fish fillet tissue, preliminary work was conducted to determine an exposure concentration and duration that would maximize eugenol residue concentrations in rainbow trout skin-on fillet tissue (Meinertz et al., 2014a). Results from that work indicated that an exposure to 100 mg/L AQUI-S 20E for 60 min maximized eugenol residues in rainbow trout fillet tissue. In addition, results indicated that sample times through 4 h after exposure would adequately characterize depletion of AQUI-S 20E residues from the fillet tissue. Therefore, those exposure and sampling parameters were incorporated into the current study.


  • Upper Midwest Environmental Sciences Center (UMESC)



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DOI 10.5066/F7BV7DPX

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