Investigation of Malachite green existence in Rainbow trout (Oncorhynchus mykiss) and common Carp (Cyprinus carpio) flesh in the area of North and South of Iran, Haraz and Shahr e Kord

Malachite green is a very effective disinfectant that usually uses for fungal invasive and parasite treatments in fish, but is very dangerous for human health. The present study evaluated the existence of Malachite green in rainbow trout and common Carp, flesh. Eight treatments which included two mean weights (0.5 and 1 kg) at the four of (Haraz, Shahrekord, north of Iran and south of Iran) with triplicates were used. The fish flesh samples were taken from under dorsal fin. Malachite green was measured by ELISA method after sample preparation. Results showed that malachite green amounts in Rainbow trout of Shahrekord samples were 0.139 – 0.391 mg/kg and 0.367 – 0.477 mg/kg for 0.5 kg fish and 0.367 – 0.477 mg/kg for 1 kg fish. These amounts in Haraz zone fish were 0.468 – 0.680 and 0.281 – 0.529 mg/kg for 0.5 and 1 kg fish, respectively. There was no significant difference in Malachite green concentrations between 0.5 and 1 kg weights in each zone, but significant difference was observed between 0.5 kg fish from Haraz and 1 kg fish form Shahrekord zone (p0.05). The Malachite green amounts in Carp North of Iran samples were 0.32-0.48 mg/kg and 0.330-0.393 mg/kg for 0.5 kg fish and 0.329-0.484 mg/kg for 1 kg fish. These amounts in south of Iran zone fish were 0.29-0.41 and 0.318-0.414 mg/kg for 0.5 and 0.298 -0.334 for 1 kg fish, respectively. There was no significant difference in malachite green concentrations between 0.5 and 1 kg weights in each zone (p>0.05).