Scientists have identified the material that led to a "very powerful" radiation in a west Delhi industrial area as Cobalt-60, the exposure to which left five people injured including a scrap dealer whose condition is serious.
Cobalt-60 is among other things used in radiography to treat cancer patients and the police suspect the radioactive material may have come from a hospital to the scrap dealer.
After scouring the Mayapuri scrapyard for two days, scientists from the department of atomic energy by Friday forenoon removed several pieces of radioactive material and packed it in shielded containers before giving the 'all clear' signal.
"The radiation level has come down to normal background level and cordoning of the road, which was done for preventing exposure to people around, has been removed. The situation is under control," S K Malhotra, head of the Public Awareness Division of DAE, said.
Panic was triggered in the locality last night after the news of radiation leak broke out with five people falling ill after coming in contact with a "mysterious shining object" in a scrap shop.
B B Bhattacharya, member of National Disaster Management Authority and former Director of Baba Atomic Research Centre, said the radiation was from a "very powerful source", as Deepak Jain, the scrap dealer undergoing treatment in Apollo Hospital, is in a serious condition.
"His bone marrow is significantly suppressed and his condition continues to be serious. Currently, he is in the ICU and a multi-disciplinary team of doctors is monitoring his progress," a medical bulletin issued by Apollo said.
"The experts have identified the material as Cobalt-60. They have identified six sources of Cobalt-60 from the scrap shop," Bhattacharya said.
Co-60 is a hard, lustrous and grey metal. Cobalt-based colours and pigments have been used since ancient times for jewellery and paints, and miners have long used the name kobold ore for some minerals.
Besides radiography, it is also used to measure thickness in nucleonic gauges and in medical applications.
Scientists from crisis management group of DAE and Atomic Energy Regulatory Board identified the source of radiation using a portable spectrometer.
Malhotra said the experts used radiation monitoring and detection equipment for prompt identification and recovery of the radioactive pieces and their safe disposal.
The experts searched the scrap shop and adjoining area from April seven soon after getting information about the incident. There are around 200 scrap shops in the market.
After the news came to light last night, police had cordoned off the area up to 1 km and barred people to enter the locality.
The incident came to light after Apollo hospital informed the government that Jain, the scrap dealer, had suffered serious injuries due to radiation.
Jain fell unconscious and his hands had turned black after coming into contact with the object, part of medical waste that was bought from a city hospital. Four workers employed by him also suffered injuries.
Jain's relative Rajesh said there were small black patches on the scrap dealer's body and it kept getting worse.
Locals also mentioned of a peculiar smell in the area.
"They were cleaning the object when one of the labourers started losing hair. His fingernails also broke. Others also then fell ill," Ajay, a local said.
"We are also probing whether the scrap material originated from abroad," a senior police official said.
"The shop, belonging to the person who had symptoms indicative of suspected radiation exposure, was found to have high radiation fields. Nearby four shops in the same area also indicated high radiation fields," Malhotra said.
Chief Minister Sheila Dikshit tonight asked people not to panic, saying all efforts will be made to ensure that such incidents do not recur.
"There is no need to panic. A team of scientists from the BARC has inspected the area and I hope they will suggest measures so that this does not happen again," she said.
Union Science and Technology Minister Prithviraj Chavan said the government is planning some mechanism to ensure that detection of such substances is brought to the notice of authorities.
"We should now plan some mechanism to ensure that scrap dealers report to authorities about detection of radioactive material found among scrap," he said.
A team from NDMA's emergency response centre rushed to the spot. They were joined by a six-member team, including a doctor, from the BARC later on Thursday evening besides 10 scientists from the Narora Atomic Power Plant.
According to a senior official, the substance was put in an almirah by the scrap dealer who was unaware of its radioactive contents.Asked how the material made it to scrap, he said, "Scrap dealers do not have requisite instruments to check whether any material they collect is radioactive or not."