Decontamination

In biology, decontamination is the removal of microbial life forms. An item is said to be sterilized when all microbial life forms have been removed.

The purpose of sterilization is to destroy every microbial life form on inanimate items, such as surgical instruments. It is done using means that are deadly to all known microbes, such as chemicals, radiation and heat. Sterilization is not done on humans because the agents that are deadly to microbes are also deadly to humans. Some microbes that live on humans are useful and protect against other harmful microbes.

Three forms of decontamination

Heat - The purpose of pasteurization is to destroy common heat sensitive pathogens without reduction in nutrient value or change in flavor. Food is being heated to 60-70 degrees celsius for 30min to 15sec. The higher the temperature, the less time it takes to kill the pathogens.

Chemical - Bactericides are a group of chemicals that kills all bacterias, except for those in endospore stage. This group of chemicals focus on bacteria, so they may or may not be harmful to other kinds of microbes.

Fungicides are a group of chemicals made to destroy fungal spores, hyphae, and yeast.

Virucides are a group of chemicals made to inactivate viruses, especially on living tissue, where their metabolism takes place.

Sporicides are a group of chemicals made to destroy bacterial endospores. Bacteria in their endospore stage are the hardened Spartans of the microbial world. The chemicals that kill endospores will surely kill all other microbes. That's why sporicides can also be regarded as sterilants.

Radiation - Gamma radiation is used as a sterilant by breaking chromosomes. An advantage of gamma radiation is that it can be applied in a factory as a part of an automated production line. The ratio of number of items sterilized above cost of purchasing and handling of the radioactive sterilant is larger than the ratio of other sterilants. However, radioactive material isn't cheap and is very hazardous to handle. Are not to be used on small quantities and on large