What acute effects does radiation have?
People exposed to a high dose of radiation over a short period show acute effects. These are to be distinguished from so-called late effects, such as tumours or genetic mutations, which often only appear decades later. A dose greater than 0.5 sievert (Sv) is considered to be a high dose of radiation. Above this threshold, adverse effects become apparent immediately or after a few days at most. The immune system is weakened, changes in blood count occur, and the digestive tract, lungs, other internal organs and the central nervous system are all damaged. With absorbed doses of 1 to 2 Sv and above, mortality is expected to be about 20%, according to radiation medicine specialists. Above a dose of 7 Sv the survival rate is zero. Of the 600 power station personnel and fire-fighters that were in the vicinity of the burning reactor directly after the accident, 134 received doses of 0.7 to 13 Sv. These include the 31 people who died in the first 3 months after the accident despite intensive t
