Mees' lines are characteristic of poisoning with which metal?

• A. Arsenic
• B. Mercury
• C. Zinc
• D. Silver

Answer: (A)

Mees' lines appear when arsenic interferes with the nail matrix during periods of exposure. They show up as transverse white bands across the nail plate, indicating a temporary halt in nail growth. As the nail continues to grow, these lines move outward and can be seen weeks to months after the arsenic exposure started. This pattern is a classic clue pointing to arsenic poisoning and can help confirm past exposure. Other metals don’t produce this nail-band sign in the same characteristic way.