A radio active isotope of P32(t1/2= 14.3 days) used in bio tracer studies of phosphorous metabolism accumulates in waste material having activity 1 milli curie. If it is unsafe to dispose of this waste material until the activity falls to 0.01 micro curie, how long must be stored the waste in led container before it is safe to dispose it.

J Ravi Kiran , 15 Years ago

Grade 11