Determining the lethal concentration of formalin to zebra fish (Danio rerio)

Formalin is an effective solution for surface and equipment disinfection and also for several aquaculture industry challenge. Since various aquatics have different sensitivity to this substance, determination of a precise concentration for cultured fish is important. Because of diversity in aquarium fish species, this topic more highlights. In this study, the method of The Organisation for Economic Co-operation and Development (OECD) were used for LC50 of formalin solution (%37) in Zebrafish. Six concentrations of this solution; 200, 213.98, 228.94, 244.99 and 262.07 mg/l plus a control group and three repeats for each group were applied. Mortality was recorded daily and at the end of 96 hours, LC10, LC50, and LC90 and the results were calculated (Probit Analysis method) 199.21, 255.57 and 327.89 mg/l respectively. Maximum safe concentration, MIC and ineffective concentration of formalin were obtained 25.56, 199.21 and 25.26 respectively for zebrafish. In order to the results, zebrafish has a good resistance to formalin solution.