Effect of lead and cadmium exposure on antioxidant defences in rock lizard Psammophilus blanfordanus

Heavy metals cause environmental pollution, and profoundly impact biological systems. This study investigates the toxic effects of cadmium (Cd) and lead (Pb) on the antioxidant defense system in Rock lizard, Psammophilus blanfordanus . The P. blanfordanus has a common occurrence in rocky and mining rich areas of Chota-Nagpur and Eastern India, exposed to heavy metals that are released as a process of weathering. Lizards were orally gavaged with CdCl₂ or Pb (NO₃)₂, to mimic the natural exposure condition and evaluated at 24, 48, and 72-hour intervals with respect to control. Results indicated that Cd-exposure significantly decreased liver protein content and catalase activity while increasing lipid peroxidation. Similarly, Pb-exposure led to significant reductions in catalase and ascorbic acid levels, with an initial increase followed by a decrease in superoxide dismutase and glutathione (GSH) levels over time. These findings underscore the oxidative stress and cellular damage induced by Cd and Pb, reflecting their detrimental impacts on reptilian physiology. The study also highlights the potential of Psammophilus blanfordanus as an indicator for monitoring environmental/heavy metal pollution in areas with mineral mining. Our study also emphasizes the need for stringent controls on heavy metal pollution in future to mitigate their ecological and health consequences.