title: Distribution and persistence of the anti sea-lice drug teflubenzuron in wild fauna and sediments around a salmon farm, following a standard treatment.
abstract: The salmon louse (Lepeoptheirus salmonis) is a challenge in the farming of Atlantic salmon (Salmo salar). To treat an infestation, different insecticides are used like the orally administered chitin synthetase inhibitor teflubenzuron. The concentrations and distribution of teflubenzuron were measured in water, organic particles, marine sediment and biota caught in the vicinity of a fish farm following a standard medication. Low concentrations were found in water samples whereas the organic waste from the farm, collected by sediment traps had concentrations higher than the medicated feed. Most of the organic waste was distributed to the bottom close to the farm but organic particles containing teflubenzuron were collected 1100 m from the farm. The sediment under the farm consisted of 5 to 10% organic material and therefore the concentration of teflubenzuron was much lower than in the organic waste. Teflubenzuron was persistent in the sediment with a stipulated halflife of 170 days. Sediment consuming polychaetes had high but decreasing concentrations of teflubenzuron throughout the experimental period, reflecting the decrease of teflubenzuron in the sediment. During medication most wild fauna contained teflubenzuron residues and where polychaetes and saith had highest concentrations. Eight months later only polychaetes and some crustaceans contained drug residues. What dosages that induce mortality in various crustaceans following short or long-term exposure is not known but the results indicate that the concentrations in defined individuals of king crab, shrimp, squat lobster and Norway lobster were high enough shortly after medication to induce mortality if moulting was imminent. Considering food safety, saith and the brown meat of crustaceans contained at first sampling concentrations of teflubenzuron higher than the MRL-value set for Atlantic salmon. The concentrations were, however, moderate and the amount of saith fillet or brown meat of crustaceans to be consumed in order to exceed ADI is relatively large.
authors.affiliation: Institute of Marine Research, P.O. Box 1870 Nordnes, N-5817 Bergen, Norway.
authors.forename: Ole B
authors.initials: OB
authors.lastname: Samuelsen
authors.affiliation: National Institute of Nutrition and Seafood Research, P.O. Box 2029 Nordnes, N-5817 Bergen, Norway.
authors.forename: Bjørn T
authors.initials: BT
authors.lastname: Lunestad
authors.affiliation: National Institute of Nutrition and Seafood Research, P.O. Box 2029 Nordnes, N-5817 Bergen, Norway.
authors.forename: Rita
authors.initials: R
authors.lastname: Hannisdal
authors.affiliation: Institute of Marine Research, P.O. Box 1870 Nordnes, N-5817 Bergen, Norway.
authors.forename: Raymond
authors.initials: R
authors.lastname: Bannister
authors.affiliation: Institute of Marine Research, P.O. Box 1870 Nordnes, N-5817 Bergen, Norway.
authors.forename: Siri
authors.initials: S
authors.lastname: Olsen
authors.affiliation: National Institute of Nutrition and Seafood Research, P.O. Box 2029 Nordnes, N-5817 Bergen, Norway.
authors.forename: Tore
authors.initials: T
authors.lastname: Tjensvoll
authors.affiliation: Institute of Marine Research, P.O. Box 1870 Nordnes, N-5817 Bergen, Norway.
authors.forename: Eva
authors.initials: E
authors.lastname: Farestveit
authors.affiliation: Institute of Marine Research, P.O. Box 1870 Nordnes, N-5817 Bergen, Norway.
authors.forename: Arne
authors.initials: A
authors.lastname: Ervik
mesh_terms: D000818:Animals; D017756:Aquaculture; D001549:Benzamides / Q000032:analysis*; D033342:Copepoda; D004202:Disinfectants / Q000032:analysis*; D004784:Environmental Monitoring; D019015:Geologic Sediments; D020317:Salmo salar; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D001549:Benzamides; D004202:Disinfectants; D014874:Water Pollutants, Chemical; C052595:teflubenzuron
keywords: Aquaculture; Crustaceans; Environmental distribution; Fish; Food safety; Sediment; Teflubenzuron