Cadmium is used primarily in rechargeable nickel‑cadmium batteries, electroplating for corrosion protection, pigments for plastics and ceramics, and PVC stabilizers. It serves in alloys, neutron‑absorbing control rods and shielding in nuclear reactors, and in semiconductors (cadmium telluride solar cells) and catalysts. Many applications have declined due to cadmium’s toxicity and environmental persistence.

Yes, cadmium is toxic and harmful to humans. It accumulates in kidneys and bones, causing kidney damage, proteinuria, bone demineralization and increased fracture risk. Inhaled cadmium damages lungs and is linked to lung cancer; chronic low-level exposure from contaminated food, water or tobacco smoke raises long-term risk. Occupational exposures are higher; prevention focuses on reducing environmental and workplace contact.

Cadmium appears in chocolate because cocoa plants absorb cadmium naturally present in soil, especially in regions with metal-rich geology, phosphate fertilizers, or industrial contamination. Cocoa beans tend to accumulate cadmium more than many crops, and processing doesn’t remove it fully. Chronic high cadmium intake can harm kidneys and bones, so regulators and manufacturers monitor and limit cadmium in cocoa and chocolate products.

Itai-itai disease is the classic illness caused by chronic cadmium exposure. It presents with severe bone pain, osteomalacia and multiple fractures, along with renal tubular dysfunction leading to proteinuria and impaired calcium handling. High cadmium intake from contaminated food or industrial exposure can also cause anemia and increased cancer risk. Preventing exposure and chelation/renal support are key to management.

Cadmium concentrates in certain foods: shellfish (oysters, mussels), some fish (tuna), organ meats (liver, kidney), cereals and rice, leafy and root vegetables, mushrooms, and seeds/nuts (sunflower seeds, Brazil nuts) and cocoa products. Levels vary with soil/water contamination and farming practices; frequent consumption of high‑cadmium items can raise body burden, so balance and source awareness matter.

Briefly: intact skin contact with elemental cadmium is unlikely to cause significant systemic poisoning because dermal absorption is low, but it can irritate skin and stain it. Soluble cadmium compounds and contact with broken skin increase risk. The main health hazards are inhalation or ingestion, causing kidney damage, bone loss and cancer. Wash exposed skin, avoid prolonged contact, and seek medical or occupational advice.