Gelatin derived from alum-tanned leather processed in tanneries often contains chromium levels far exceeding safety standards. So what is chromium, and what health risks does excessive exposure pose?
Experts explain that chromium is a blue-white, multivalent metal element, commonly found in trivalent, hexavalent, and divalent forms.Hard and brittle with corrosion resistance, it is widely used in stainless steel and similar products. Chromium is also an essential trace element for the human body. However, excessive chromium intake poses significant health risks, with toxicity varying by valence state. While divalent chromium is minimally toxic, trivalent chromium readily exhibits toxicity in the human body.
Long-term, high intake of trivalent chromium can impair the body's antioxidant system, increasing susceptibility to chronic oxidative diseases like diabetes and hypertension. Furthermore, damage to the antioxidant system may lead to abnormal proliferative diseases such as tumors.
Compared to trivalent chromium, hexavalent chromium exhibits significantly higher toxicity—approximately 100 times greater. Clinically, the harm caused by hexavalent chromium and its compounds typically manifests in three primary ways:First, it damages the skin, causing dermatitis, pharyngitis, and similar conditions. Second, it harms the respiratory system, triggering pneumonia, bronchitis, and related diseases. Third, it affects the digestive system; accidental ingestion or prolonged exposure to chromate salts can easily lead to gastritis, gastric ulcers, and intestinal ulcers.
Experts further emphasize that excessive intake of hexavalent chromium can severely impair kidney function and even cause cancer.
Prolonged exposure to high levels of chromium ions may damage renal tubular function, as observed in animal studies. Additionally, it is associated with tumor development, particularly malignant cancers like lung and esophageal cancer, linked to long-term chromium ion intake.