PERSISTENCE OF RESIDUES OF MALACHITE GREEN IN EUROPEAN EEL (Anguilla anguilla) AFTER WATER-BORNE EXPOSURE OF JUVENILE EELS

• Main Authors: Raoul V. Kuiper, Peter Scherpenisse, Aldert A. Bergwerff
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Slaughter; Anguilla anguilla
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.494.9655; http://www.instrument.com.cn/bbs/images/upfile/20059295613.pdf

The depletion of malachite green and leuco-malachite green was followed on a long-term time-scale in glass eels 4.1 g of average weight. The eels were exposed to malachite green at 0.1 mg/L bath water for 24 h at a water temperature varying between 23 and 26.5 °C. After treatment, the juvenile fish were transferred into a malachite green-free tank integrated in a recirculation water-supply system of an eel farm. At regular time-intervals, ten fish were collected for HPLC analysis. The highest average concentration of malachite green was found at 0.4 mg/kg 6 h after the start of the treatment. The highest average residue level of the primary metabolite leuco-malachite green was determined in fish 3 h after the end of the treatment at 0.7 mg/kg. At 2,400 h after exposure, leuco-malachite green was still present at an average level of 15 µg/kg whereas malachite green was undetectable. These fish, however, did not grow during the study. Fast growing eels at 0.1 kg slaughter weight, which were treated at 0.15 mg/L malachite green at their glass eel stage (0.3 g body weight) eleven months before slaughter, contained non-detectable residues of malachite green as established by HPLC and LC/MS/MS analyses.