Chemistry 2010-2011

Radiation sickness is damage to your body caused by a very large dose of radiation often received over a short period of time (acute). The amount of radiation absorbed by the body — the absorbed dose — determines how sick you'll be.

Although radiation sickness is serious and often fatal, it's rare. Since the atomic bombings of Hiroshima and Nagasaki, Japan, during World War II, most cases of radiation sickness have happened after nuclear industrial accidents, such as the 1986 nuclear reactor accident at a power station in Chernobyl, Ukraine

Radiation may come from either an external source, such as an x-ray machine, or an internal source, such as an injected radioisotope. The impact of radiation on living tissue is complicated by the type of radiation and the variety of tissues.

Altering chemical bonds may change composition or structure. Ionizing radiation is powerful enough to do this. For example, a typical ionization releases six to seven times the energy needed to break the chemical bond between two carbon atoms.

It takes much longer for the biological effects to become apparent. If the damage is sufficient to kill the cell, the effect may become noticeable in hours or days.

When working properly, nuclear reactors produce large amounts of heat via nuclear fission reactions. The heat converts the surrounding water into steam, which turns turbines and generates electricity. But if you remove the water, you also remove the most important cooling element in a nuclear reactor and open up the possibility for nuclear meltdown.