Toxic effects of tin(II) chloride on hematological parameters and histopathology of gills and intestines in common carp (Cyprinus carpio)

Background and Objectives: Tin(II) chloride (SnCl₂) was selected because of its industrial applications and the potential release of inorganic tin into aquatic environments, motivating an assessment of its toxic effects in freshwater fish. Therefore, the aim of this study was to investigate the toxic effects of sublethal concentrations of tin chloride (SnCl۲) on blood parameters and gill and intestinal tissues of common carp. Methods: For this purpose, the ۹۶-h median lethal concentration (LC₅₀) of SnCl₂ in common carp weighing ۴۰ ± ۳ g was determined through an acute toxicity test conducted according to OECD Test Guideline ۲۰۳. Then, ۱۰, ۲۵, and ۵۰% of the LC۵۰-۹۶h were selected as sublethal concentrations of SnCl۲. After the end of the experimental period (۲۸ days), hematological and histological examinations were performed. Results: The ۹۶-h LC₅₀ of SnCl₂ was ۱۳۱.۸۲ mg/L. Compared with the control, red blood cell (RBC) counts decreased significantly and white blood cell (WBC) counts increased significantly at ۲۵% and ۵۰% of the LC₅₀, whereas hematocrit (HCT) and hemoglobin (HGB) decreased significantly at ۵۰% of the LC₅₀ (p < ۰.۰۵). Gill lesions included shortening and curvature of secondary lamellae, oedema, and necrosis. Intestinal changes included increased goblet cell numbers, goblet cell swelling, increased blood cell presence, and expansion of villous structures.Conclusion: Under the experimental conditions, ۲۸-day exposure to SnCl₂ was associated with altered hematological parameters and histopathological damage in the gills and intestines of common carp.

کلیدواژه ها:

hematocrit ، Hemoglobin ، Median lethal concentration ، Necrosis ، Red blood cells ، white blood cells