A 45-year-old man presents with hyperpigmentation of the palms, keratosis of the feet, and peripheral neuropathy. He has been drinking tube-well water in an endemic belt for 15 years. Which investigation is the gold standard for confirming the suspected toxicity?

• A Blood lead level
• B Urinary fluoride level
• C Water arsenic estimation
• D Hair and nail arsenic estimation ✓

Explanation

The triad of hyperpigmentation, keratosis, and peripheral neuropathy with chronic tube-well water exposure is classic chronic arsenicosis. While water testing identifies the source, the gold standard for biological confirmation of chronic exposure is arsenic estimation in hair and nails, which reflects cumulative deposition. Blood lead would be for lead poisoning. Water estimation confirms exposure source but not body burden.

Reference: Park's Textbook of Preventive and Social Medicine, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.