Beyond visual phytotoxicity: A standardized in vivo evaluation of cumulative systemic damage from potentially toxic elements (PTEs) in sewage irrigated crops.

Wastewater irrigation facilitates the entry of potentially toxic elements (PTEs) into the food chain, often posing significant health risks even when crops appear visually healthy and phytotoxicity symptoms are absent. This study investigated the sub-chronic toxicological impacts of consuming heavy metal-contaminated spinach and cabbage grown in sewage-irrigated soils from three industrial districts in Pakistan (Chiniot, Faisalabad, and Kasur) using a Wistar rat model. Rats were fed a diet containing 20% contamination-derived crops for 90 days. Results indicated a dose-dependent increase in Bioaccumulation Index (BAI) and tissue-specific toxicity, with Cadmium levels following the descending order: liver > kidney > lungs > brain > heart. Consumption of contaminated produce caused significant (P < 0.05) physiological impairment, including an average reduction in body weight of 110g in the highest contamination group (Kasur) compared to the control. Hematological profiles showed an anemic condition, characterized by reduced red blood cells (RBC), hemoglobin (HGB), and hematocrit (HCT), alongside leucocytosis. Biochemical analyses revealed hepatotoxicity and nephrotoxicity, evidenced by elevated Aspartate aminotransferase (AST), Alanine amino transferase (ALT), Alkaline Phosphatase (ALP), and Creatinine (CRE), and decreased serum total protein (TP) and albumin (ALB). Furthermore, the brain exhibited the highest susceptibility to Pb attack, while bone tissues acted as the primary long-term sink for lead deposition. These findings demonstrate that visual inspection of crops is insufficient for assessing safety. The study provides a robust toxicological framework linking environmental contamination to biological endpoints, suggesting a high risk of chronic systemic collapse in human populations consuming similar produce.