New Delhi: The leak of radioactive material today at Delhi's international airport was of sodium iodide 131, an official at India's Atomic Energy Regulatory Board (AERB) told sources.

"It's a localized leak," said AERB Vice-Chairman R. Bhattacharya. Sodium iodide 131 is used in so-called nuclear medicine, and is used for treatment of hyperthyroidism and thyroid cancers. It emits radiation and must be handled with care to minimise inadvertent exposure to health workers and patients.

Bhattarcharya said that the AERB was part of an emergency response team at the scene of the incident. He said that one of four consignments of sodium iodide had leaked. It had been "separated" and the area cordoned off, he said.