Atomic Energy Regulatory Board today slapped a notice on Delhi University to explain how safety rules were violated after the radiation exposure in a Delhi scrap market was traced to its Chemistry department.<br/><br/>Vice-Chancellor Prof Deepak Pental in the meantime said the university took moral responsibility and was very apologetic for what happened and the damages caused.<br/><br/>Panic had gripped Mayapuri in the first week of April when 11 people were admitted to hospitals after they were exposed to radiation in a scrap market. A worker in the scrap shop from where the Cobalt 60 was discovered had also died due to exposure to radiation whose origin was a mystery for days.<br/>