Occupational risk prevention - Biological hazards

Microorganisms (bacteria, viruses, fungi, etc.) are found naturally in the environment (water, soil), where they form the basis of all food chains, and in living beings (in the intestine, skin, nose, etc.). Their wide distribution is explained by the diversity of their metabolisms, metabolism being the set of chemical reactions that take place in a living organism.

Most micro-organisms are harmless to humans, but some - pathogens - can cause disease. Conversely, others are of interest to man and are used industrially in biotechnologies [1] [2] [3].

• Certain micro-organisms have been used for thousands of years in food processing (alcoholic beverages, bread, cheese). More recently, processes exploiting the ability of certain micro-organisms to degrade numerous organic or mineral molecules have been developed to clean up soil, water and air.

• Some micro-organisms produce molecules that can be used in healthcare (antibiotics, vitamins...) or industry (surfactants...).

• Genetically modified micro-organisms contain one or more foreign genes, providing a new trait that can be passed on to subsequent generations. These genes can control the synthesis of an unusual or modified molecule, or modify the level of synthesis of the molecule (it is possible to obtain cultures in which 30% of the weight consists of the desired molecule). This technique enables the industrial production of molecules such as insulin or growth hormone.

• Some micro-organisms have insecticidal properties.