Biocide
From Free net encyclopedia
A biocide is a chemical substance capable of killing different forms of living organisms used in fields such as medicine, agriculture, forestry, and mosquito control.
A biocide can be:
- A pesticide, which includes fungicides, herbicides, insecticides, algicides, moluscicides, miticides and rodenticides.
- An antimicrobial, which includes germicides, antibiotics, antibacterials, antivirals, antifungals, antiprotoas and antiparasites. See also spermicide.
Biocides can also be added to other materials (typically liquids) to protect the material from biological infestation and growth. For example, certain types of quaternary ammonium compounds (quats) can be added to pool water or industrial water systems to act as an algicide, protecting the water from infestation and growth of algae. Chlorine can be added in low concentrations to water as one of the final steps in wastewater treatment as a general biocide to kill micro-organisms, algae, etc. It is often impractical to store and use poisonous chlorine gas for water treatment, so alternative methods of effectively adding chlorine are used. Adding hypochlorite solutions to pools, etc. is one possible solution. Hypochlorite can gradually release chlorine into the water. Even more convenient for some users are compounds such as sodium dichloro-s-triazinetrione (dihydrate or anhydrous), sometimes referred to as dichlor, and sodium trichloro-s-triazinetrione, sometimes referred to as trichlor. These compounds are stable while solid and may be used in powdered, granular, or tablet form. When added in small amounts to pool water or industrial water systems, the chlorine atoms hydrolyze from the rest of the molecule forming hypochlorous acid (HOCl) which acts as a general biocide killing germs, micro-organisms, algae, etc. Halogenated hydantoin compounds are also used as biocides.