04-29-2010, 01:11 AM
Quote:Radioactive source traced to DU lab
pioneer.com
Staff Reporter | New Delhi
Traders bought unutilised gamma irradiator from Chemistry Dept
A callous Delhi University administration has been found responsible for the exposure of eight persons to radiation from a Cobalt-60 source in Mayapuri. In a startling revelation, the Delhi Police on Wednesday claimed to have traced the origin of the radioactive Cobalt-60 that has left one dead and seven critically ill so far to Delhi Universityââ¬â¢s Chemistry Department.
The police said that Cobalt-60, contained in a gamma irradiator, was lying unused in the laboratory for the last 25 years. Joint Commissioner of Police (Southern Range) Ajay Kashyap said that the radioactive isotope was brought to the scrap market by the scrap dealers after the university sold the gamma irradiator through auction in February this year. ââ¬ÅThe gamma irradiator was purchased by the Chemistry Department in 1968 from Canada and was lying unused since 1985. The same irradiator was bought by the scrap dealers,ââ¬Â said Kashyap. The harmful radiation claimed a life on Monday while condition of two others is said to be serious.
The Joint Commissioner said that the scrap dealers in order to resell it, dismantled the equipment and in the process, the lead covering on the radioactive substance pealed off leading to radiation exposure. ââ¬ÅThe equipment was in use till 1985 and after that it was lying in a room unused. In February, a committee of the Chemistry Department decided to sell it and the Mayapuri scrap dealers bought it through auction,ââ¬Â he said, adding that the four workers who were admitted to city hospitals were shown photographs of the equipment and one of them identified it.
Notably, gamma irradiator is an instrument used for the irradiation of electromagnetic gamma rays for sterilisation or decontamination, especially those of medical equipment. According to experts, the most common source of gamma rays for irradiation processing comes from the radioactive isotope Cobalt-60. It is manufactured specifically for the gamma irradiation process.
Gamma rays are the most energetic form of electromagnetic radiation and also have significant effects on properties of polymers and polymer-containing composites.
Deputy Commissioner of Police (West) Sharad Aggarwal said that during investigation, it was found that the harmful substance was auctioned by the university authorities on February 26 this year. ââ¬ÅIt was bought by one Harcharan Singh Bhola having scrap shop at D2/80, Mayapuri, Phase-II. He removed the iron part from the cell and sold the lead part to one Giriraj Gupta. He got it dismantled and sold the lead to some other scrap dealers. However, the iron part found embedded in lead was kept by him,ââ¬Â he said. Apparently, part of the iron scrap of gamma cell removed by Haracharan Singh Bhola reached Deepak Jain through Rajinder, who suffered the maximum radioactive exposure and died.
Aggarwal said that on sustained interrogation of Giriraj from whose shop two sources were recovered, disclosed about purchasing the bulk quantity of lead from Harcharan Singh Bhola. Thereafter Bhola was thoroughly interrogated to know about the source of lead sold to Giriraj. ââ¬ÅBhola disclosed about purchasing a big machine having bulk quantity of lead in auction from the university. On verification, it was confirmed that the machine referred by Bhola was actually gamma cell which was sold in auction to Harcharan Singh Bhola,ââ¬Â the DCP said, adding that they would examine if the guidelines were properly followed while selling the equipment.
On April 8, Mayapuri came in the grip of Cobalt-60 radiation, when five persons were admitted to hospitals after they were exposed to the radioactive material. A worker in the scrap shop from where the Cobalt-60 was discovered has died due to exposure to radiation. At one stage of the investigation, it was suspected that the scrap material came from abroad. Some reports even suggested that the scrap originated from medical waste from a city hospital. Eleven sources of radiation were detected in the Mayapuri scrap market. Experts from Department of Atomic Energy (DAE) and Bhabha Atomic Research Centre (BARC) had scanned all the 800 shops in the scrap market and said that the locality was radiation-free.
Whatââ¬â¢s Gamma irradiator?
Gamma irradiation is a means of sterilisation or decontamination, especially those of medical equipment. In a gamma irradiator, the products or substances are exposed to gamma rays
It is also known as a ââ¬ËCold Processââ¬â¢ as the temperature of the processed product doesnââ¬â¢t significantly increase. It is not dependant on humidity, temperature, vacuum or pressure
The most common source of gamma rays for irradiation processing comes from the radioactive isotope Cobalt-60. It is manufactured specifically for the gamma irradiation process.