Uptake and depletion curve of Diflubenzuron in marine mussels (Mytilus chilensis) under controlled conditions

• A simple and fast HPLC method to detect DFB in mussel tissues was developed.
• The technique showed a good linearity, specificity, recovery and precision.
• The quantification limits was 100 ng g− 1 wet weight.
• Mussels showed to uptake DFB.
• The half-life of DFB in mussels was 1.2 days.

Caligus rogercresseyi is the main ectoparasite affecting farmed salmonid species in Southern Chile. Diflubenzuron (DFB) is one of the medications used to control this ectoparasite in salmon farming. Since the mussel production share the same ecosystem as salmon farming, mussels could be exposed to medicated uneaten feed and faeces from salmon farming.The aim of this study was to determine the anti-parasite uptake and depuration of Chilean mussel (Mytilus chilensis) facing a Diflubenzuron extreme exposure under controlled conditions. A simple detection and quantification method of DFB in mussel's soft tissues was developed and validated. The compound was extracted using the Quechers (Quick, Easy, Cheap Effective, Rugged and Safe) method, and quantified using HPLC (High Performance Liquid Chromatography) with a diode array detection. The presence of DFB in mussel's soft tissues was demonstrated. The maximum concentration of DFB in mussels reached 1000 ng g− 1. The calculated half-life for DFB in mussel's soft tissues is 1.2 days, suggesting that DFB is quickly eliminated.Statement of relevanceIt's unlikely that mussel's food security is affected by DFB.