Sub-lethal Effects of Imidacloprid on Nile Tilapia (Oreochromis niloticus)

• Published in: Water, air, and soil pollution Vol. 231; no. 1
• Main Authors: Günal, Aysel Çağlan, Erkmen, Belda, Paçal, Elif, Arslan, Pınar, Yildirim, Zuhal, Erkoç, Figen
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 2020; Springer; Springer Nature B.V
• Subjects: Agrochemicals; Antioxidants; Aquariums; Aquatic ecosystems; Atmospheric Protection/Air Quality Control/Air Pollution; Climate Change/Climate Change Impacts; Drinking water; Earth and Environmental Science; Ecosystems; Environment; Environmental monitoring; Enzymes; Fishes; Freshwater fishes; Histochemistry; Histopathology; Hydrogeology; Hyperemia; Imidacloprid; Insecticides; Lethal effects; Lipid peroxidation; Liver; Marine fishes; Oreochromis niloticus; Oxidative stress; Peroxidation; Ponds; Soil Science & Conservation; Soil treatment; Tilapia; Tissues; Water Quality/Water Pollution; Lipid peroxidation; Histopathology; Oxidative stress biomarkers; Antioxidant system biomarkers
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1007/s11270-019-4366-8

Imidacloprid (1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine (CAS No: 138261–41-3), neonicotinoid insecticide, and agricultural plant protectants were applied as seed and soil treatments. The aim of the present study is to determine the effects of sub-lethal imidacloprid concentrations on the histopathology and oxidative stress parameters with lipid peroxidation (LPO) to standard non-target test organism, tilapia (
Oreochromis niloticus
). 50 and 100 mgL
−1
imidacloprid concentrations were chosen for experimental groups with control group. Fish were stocked in 60 L glass aquaria, maintained in aerated and dechlorinated tap water. The mean weight and length of tilapia were 37.78 ± 2.19 g and 12.98 ± 0.22 cm, respectively. After 24 and 96 h exposure to sub-lethal imidacloprid concentrations, the fish were sacrificed; tissue samples of gill and liver were snap frozen in liquid nitrogen for oxidative stress parameters and LPO assays, fixed (buffered 10% formalin) for histopathology. After exposure to sub-lethal imidacloprid, LPO was induced in both tissues. MDA levels were increased in both tissues, while GSH levels were reduced at the high concentration of imidacloprid in the gill tissues after 96 h and both concentrations in the liver tissues (
P
 < 0.05). There were no significant differences for antioxidant enzymes CAT, SOD and GPx between exposed and control groups (
P
 > 0.05). Gill tissues revealed hyperaemia, epithelial lifting, fusion of secondary lamellae and telangiectasia, whereas hyperaemia, mononuclear cell infiltration vacuolization of hepatocytes and hydropic degeneration were observed in liver tissues. Imidacloprid is very toxic to the non-target species in the aquatic ecosystem even at sub-lethal concentrations.