Ascorbic Acid as a Dual Therapeutic and Preventive Agent against Lead and Cadmium Toxicity: Evidence from Controlled...

Lead (Pb) and cadmium (Cd) are pervasive toxicants that bioaccumulate and cause multisystem injury. Two controlled experiments were conducted in quails, subdivided into co‑exposure (ascorbic acid (AA) given concurrently with Pb or Cd for four weeks) and post‑exposure (AA administered for three weeks after one week of metal exposure). Birds received Pb acetate or Cd chloride (500 ppm) with AA (1000 ppm). In the Pb experiment, co‑exposure with AA significantly reduced tissue burdens compared with Pb alone: liver (16.7 ± 0.8 vs. 29.0 ± 1.3 ppb), thigh (3.2 ± 0.6 vs. 10.6 ± 1.3 ppb), brisket (2.4 ± 0.4 vs. 13.7 ± 0.5 ppb), brain (21.7 ± 3.3 vs. 36.0 ± 3.9 ppb), bone (567.2 ± 81.6 vs. 1411.2 ± 9.8 ppb), and blood (15.1 ± 1.4 vs. 36.9 ± 3.7 ppb; all p < 0.001). Post‑exposure AA also lowered concentrations: liver (3.9 ± 1.4 vs. 12.3 ± 0.3 ppb), thigh (1.9 ± 0.3 vs. 11.3 ± 1.0 ppb), brisket (1.2 ± 0.1 vs. 6.4 ± 0.5 ppb), brain (5.7 ± 0.2 vs. 25.4 ± 1.4 ppb), bone (109.9 ± 23.6 vs. 384.5 ± 35.7 ppb), and blood (9.2 ± 0.9 vs. 19.9 ± 1.7 ppb; all p < 0.001). In the Cd experiment, co‑exposure with AA reduced tissue levels: liver (4381.5 ± 281.2 vs. 9291.1 ± 278.3 ppb), thigh (47.2 ± 1.0 vs. 116.6 ± 1.7 ppb), brisket (50.6 ± 3.6 vs. 82.8 ± 2.3 ppb), brain (31.4 ± 1.1 vs. 66.1 ± 2.7 ppb), bone (416.7 ± 11.0 vs. 562.3 ± 10.9 ppb), and blood (174.1 ± 7.9 vs. 298.5 ± 6.6 ppb; all p < 0.001). Post‑exposure AA likewise lowered burdens: liver (1109.5 ± 156.8 vs. 3200.6 ± 324.4 ppb), thigh (5.3 ± 0.5 vs. 32.6 ± 4.1 ppb), brisket (3.8 ± 0.7 vs. 30.4 ± 2.3 ppb), brain (6.5 ± 0.9 vs. 44.5 ± 5.8 ppb), bone (43.5 ± 3.1 vs. 187.6 ± 14.6 ppb), and blood (63.3 ± 1.1 vs. 143.5 ± 15.4 ppb; all p < 0.001). Across both paradigms, co‑exposure with AA generally produced larger relative reductions in tissue burdens compared with post‑exposure treatment, although both approaches were effective. Given its safety, availability, and low cost, AA may be incorporated into strategies for populations at risk of heavy metal exposure.