Lead poisoning is classically associated with accumulation in bones and metaphyseal endplate changes visible on X-ray. Which metal is responsible?

Lead poisoning is classically associated with accumulation in bones and metaphyseal endplate changes visible on X-ray. Which metal is responsible?

• A. Arsenic
• B. Lead
• C. Mercury
• D. Cyanide

Answer: (B)

Lead poisoning is characterized by its accumulation in bone, especially in growing children, where lead deposits at the growth plates create dense transverse lines seen on X-ray, known as lead lines. This radiographic finding reflects lead’s affinity for the mineralizing matrix in the metaphysis and its long bone half-life, so the lines are a classic clue in the diagnosis. Lead also causes Burton lines in the gums and a range of systemic effects from microcytic anemia to neurodevelopmental issues, all tied to its interference with heme synthesis and other enzymes. The other metals listed produce different toxic signatures—arsenic may cause Mees lines on nails, mercury-related symptoms like erethism, and cyanide causes rapid cellular hypoxia—so they don’t explain the metaphyseal endplate changes.

Lead poisoning is characterized by its accumulation in bone, especially in growing children, where lead deposits at the growth plates create dense transverse lines seen on X-ray, known as lead lines. This radiographic finding reflects lead’s affinity for the mineralizing matrix in the metaphysis and its long bone half-life, so the lines are a classic clue in the diagnosis. Lead also causes Burton lines in the gums and a range of systemic effects from microcytic anemia to neurodevelopmental issues, all tied to its interference with heme synthesis and other enzymes. The other metals listed produce different toxic signatures—arsenic may cause Mees lines on nails, mercury-related symptoms like erethism, and cyanide causes rapid cellular hypoxia—so they don’t explain the metaphyseal endplate changes.