Biocide
Encyclopedia
A biocide is a chemical substance
or microorganism
which can deter, render harmless, or exert a controlling effect on any harmful organism by chemical or biological means. Biocides are commonly used in medicine
, agriculture
, forestry
, and industry
. Biocidal substances and products are also employed as anti-fouling agents or disinfectants under other circumstances: chlorine, for example, is used as a short-life biocide in industrial water treatment but as a disinfectant in swimming pools. Many biocides are synthetic, but a class of natural biocides, derived from e.g. bacteria and plants, includes brassica oleracea, brassica oleracea gemmifera, and clostridium botulinum bacteria.
A biocide can be:
s) to protect them against biological infestation and growth. For example, certain types of quaternary ammonium compounds (quat
s) are added to pool
water
or industrial water systems to act as an algicide, protecting the water from infestation and growth of algae
. It is often impractical to store and use poisonous chlorine gas for water treatment, so alternative methods of adding chlorine are used. These include hypochlorite
solutions, which gradually release chlorine into the water, and compounds like sodium dichloro-s-triazinetrione (dihydrate or anhydrous), sometimes referred to as "dichlor", and trichloro-s-triazinetrione, sometimes referred to as "trichlor". These compounds are stable while solids 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, and so on. Halogenated hydantoin
compounds are also used as biocides.
A new innovation is the use of copper and its alloys (brass
es, bronze
s, cupronickel
, copper-nickel-zinc, and others) as biocidal surfaces to destroy a wide range of microorganisms (E. coli
O157:H7, methicillin
-resistant Staphylococcus aureus
(MRSA), Staphylococcus
, Clostridium difficile
, influenza A virus, adenovirus
, and fungi
).
The United States Environmental Protection Agency
has approved the registration of 355 different antimicrobial copper alloys that kill E. coli
O157:H7, methicillin
-resistant Staphylococcus aureus
(MRSA), Staphylococcus
, Enterobacter aerogenes, and Pseudomonas aeruginosa in less than 2 hours of contact. As a public hygienic measure in addition to regular cleaning, antimicrobial copper alloys are being installed in healthcare facilities and in a subway transit system.
compounds such as TBT
, have been shown to have severe and long-lasting impacts on marine eco-systems and such materials are now banned in many countries for commercial and recreational vessels (though sometimes still used for naval
vessels).
Disposal of used or unwanted biocides must be undertaken carefully to avoid serious and potentially long-lasting damage to the environment.
MAIN GROUP 1: Disinfectants and general biocidal products
MAIN GROUP 2: Preservatives
MAIN GROUP 3: Pest control
MAIN GROUP 4: Other biocidal products
Chemical substance
In chemistry, a chemical substance is a form of matter that has constant chemical composition and characteristic properties. It cannot be separated into components by physical separation methods, i.e. without breaking chemical bonds. They can be solids, liquids or gases.Chemical substances are...
or microorganism
Microorganism
A microorganism or microbe is a microscopic organism that comprises either a single cell , cell clusters, or no cell at all...
which can deter, render harmless, or exert a controlling effect on any harmful organism by chemical or biological means. Biocides are commonly used in medicine
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
, agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
, forestry
Forestry
Forestry is the interdisciplinary profession embracing the science, art, and craft of creating, managing, using, and conserving forests and associated resources in a sustainable manner to meet desired goals, needs, and values for human benefit. Forestry is practiced in plantations and natural stands...
, and industry
Industry
Industry refers to the production of an economic good or service within an economy.-Industrial sectors:There are four key industrial economic sectors: the primary sector, largely raw material extraction industries such as mining and farming; the secondary sector, involving refining, construction,...
. Biocidal substances and products are also employed as anti-fouling agents or disinfectants under other circumstances: chlorine, for example, is used as a short-life biocide in industrial water treatment but as a disinfectant in swimming pools. Many biocides are synthetic, but a class of natural biocides, derived from e.g. bacteria and plants, includes brassica oleracea, brassica oleracea gemmifera, and clostridium botulinum bacteria.
A biocide can be:
- A pesticidePesticidePesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.A pesticide may be a chemical unicycle, biological agent , antimicrobial, disinfectant or device used against any pest...
: this includes fungicideFungicideFungicides are chemical compounds or biological organisms used to kill or inhibit fungi or fungal spores. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality and profit. Fungicides are used both in agriculture and to fight fungal infections in animals...
s, herbicideHerbicideHerbicides, also commonly known as weedkillers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic "imitations" of plant...
s, insecticideInsecticideAn insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
s, algicides, molluscicideMolluscicideMolluscicides, also known as snail baits and snail pellets, are pesticides against molluscs, which are usually used in agriculture or gardening to control gastropod pests like slugs and snails that can damage crops by feeding on them....
s, miticideMiticideAcaricides are pesticides that kill members of the Acari group, which includes ticks and mites.Acaricides are used both in medicine and agriculture, although the desired selective toxicity differs between the two fields.-Terminology:...
s and rodenticides. - An antimicrobialAntimicrobialAn anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...
: this includes germicides, antibioticAntibioticAn antibacterial is a compound or substance that kills or slows down the growth of bacteria.The term is often used synonymously with the term antibiotic; today, however, with increased knowledge of the causative agents of various infectious diseases, antibiotic has come to denote a broader range of...
s, antibacterials, antiviralsAntiviral drugAntiviral drugs are a class of medication used specifically for treating viral infections. Like antibiotics for bacteria, specific antivirals are used for specific viruses...
, antifungals, antiprotozoalAntiprotozoal agentAntiprotozoal agents is a class of pharmaceuticals used in treatment of protozoan infection.Protozoans have little in common with each other and so agents effective against one pathogen may not be effective against another...
s and antiparasites. See also spermicideSpermicideSpermicide is a contraceptive substance that eradicates sperm, inserted vaginally prior to intercourse to prevent pregnancy. As a contraceptive, spermicide may be used alone. However, the pregnancy rate experienced by couples using only spermicide is higher than that of couples using other methods...
.
Uses
Biocides can be added to other materials (typically liquidLiquid
Liquid is one of the three classical states of matter . Like a gas, a liquid is able to flow and take the shape of a container. Some liquids resist compression, while others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly...
s) to protect them against biological infestation and growth. For example, certain types of quaternary ammonium compounds (quat
Quat
Quat may refer to:* Quaternary ammonium cation, a class of chemical molecules* Quaternion, a non-commutative extension of the complex numbers* Khat, an African plant whose leaves are chewed as a stimulant...
s) are added to pool
Swimming pool
A swimming pool, swimming bath, wading pool, or simply a pool, is a container filled with water intended for swimming or water-based recreation. There are many standard sizes; the largest is the Olympic-size swimming pool...
water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
or industrial water systems to act as an algicide, protecting the water from infestation and growth of algae
Algae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...
. It is often impractical to store and use poisonous chlorine gas for water treatment, so alternative methods of adding chlorine are used. These include hypochlorite
Hypochlorite
The hypochlorite ion, also known as chlorate anion is ClO−. A hypochlorite compound is a chemical compound containing this group, with chlorine in oxidation state +1.Hypochlorites are the salts of hypochlorous acid...
solutions, which gradually release chlorine into the water, and compounds like sodium dichloro-s-triazinetrione (dihydrate or anhydrous), sometimes referred to as "dichlor", and trichloro-s-triazinetrione, sometimes referred to as "trichlor". These compounds are stable while solids 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
Hypochlorous acid
Hypochlorous acid is a weak acid with the chemical formula HClO. It forms when chlorine dissolves in water. It cannot be isolated in pure form due to rapid equilibration with its precursor...
(HOCl) which acts as a general biocide killing germs, micro-organisms, algae, and so on. Halogenated hydantoin
Hydantoin
Hydantoin, which is also known as glycolylurea, is a heterocyclic organic compound that can be thought of as a cyclic "double-condensation reaction" product of glycolic acid and urea...
compounds are also used as biocides.
A new innovation is the use of copper and its alloys (brass
Brass
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin...
es, bronze
Bronze
Bronze is a metal alloy consisting primarily of copper, usually with tin as the main additive. It is hard and brittle, and it was particularly significant in antiquity, so much so that the Bronze Age was named after the metal...
s, cupronickel
Cupronickel
Cupronickel or copper-nickel or "cupernickel" is an alloy of copper that contains nickel and strengthening elements, such as iron and manganese. Cupronickel is highly resistant to corrosion in seawater, because its electrode potential is adjusted to be neutral with regard to seawater...
, copper-nickel-zinc, and others) as biocidal surfaces to destroy a wide range of microorganisms (E. coli
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
O157:H7, methicillin
Methicillin
Meticillin or methicillin is a narrow-spectrum beta-lactam antibiotic of the penicillin class. It should not be confused with the antibiotic metacycline.-History:Methicillin was developed by Beecham in 1959...
-resistant Staphylococcus aureus
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
(MRSA), Staphylococcus
Staphylococcus
Staphylococcus is a genus of Gram-positive bacteria. Under the microscope they appear round , and form in grape-like clusters....
, Clostridium difficile
Clostridium difficile
Clostridium difficile , also known as "CDF/cdf", or "C...
, influenza A virus, adenovirus
Adenoviridae
Adenoviruses are medium-sized , nonenveloped icosahedral viruses composed of a nucleocapsid and a double-stranded linear DNA genome...
, and fungi
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...
).
The United States Environmental Protection Agency
United States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...
has approved the registration of 355 different antimicrobial copper alloys that kill E. coli
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
O157:H7, methicillin
Methicillin
Meticillin or methicillin is a narrow-spectrum beta-lactam antibiotic of the penicillin class. It should not be confused with the antibiotic metacycline.-History:Methicillin was developed by Beecham in 1959...
-resistant Staphylococcus aureus
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
(MRSA), Staphylococcus
Staphylococcus
Staphylococcus is a genus of Gram-positive bacteria. Under the microscope they appear round , and form in grape-like clusters....
, Enterobacter aerogenes, and Pseudomonas aeruginosa in less than 2 hours of contact. As a public hygienic measure in addition to regular cleaning, antimicrobial copper alloys are being installed in healthcare facilities and in a subway transit system.
Hazards and environmental risks
Because biocides are intended to kill living organisms, many biocidal products pose significant risk to human health and welfare. Great care is required when handling biocides and appropriate protective clothing and equipment should be used. The use of biocides can also have significant adverse effects on the natural environment. Anti-fouling paints, especially those utilising organic tinTin
Tin is a chemical element with the symbol Sn and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to both neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4...
compounds such as TBT
Tributyltin
Tributyltin compounds are a group of compounds containing the 3Sn moiety, such as tributyltin hydride or tributyltin oxide. They are the main active ingredients in certain biocides used to control a broad spectrum of organisms...
, have been shown to have severe and long-lasting impacts on marine eco-systems and such materials are now banned in many countries for commercial and recreational vessels (though sometimes still used for naval
Navy
A navy is the branch of a nation's armed forces principally designated for naval and amphibious warfare; namely, lake- or ocean-borne combat operations and related functions...
vessels).
Disposal of used or unwanted biocides must be undertaken carefully to avoid serious and potentially long-lasting damage to the environment.
European Community Classification
The Biocidal Products Directive 98/8/EC (BPD), the classification of biocides, is broken down into 23 product types (i.e. application categories), with several comprising multiple subgroups:MAIN GROUP 1: Disinfectants and general biocidal products
- Product-type 1: Human hygiene biocidal products
- Product-type 2: Private area and public health area disinfectants and other biocidal products
- Product-type 3: Veterinary hygiene biocidal products
- Product-type 4: Food and feed area disinfectants
- Product-type 5: Drinking water disinfectants
MAIN GROUP 2: Preservatives
- Product-type 6: In-can preservatives
- Product-type 7: Film preservatives
- Product-type 8: Wood preservativesWood preservationAll measures that are taken to ensure a long life of wood fall under the definition wood preservation . Apart from structural wood preservation measures, there are a number of different preservatives and processes that can extend the life of wood, timber, wood structures or engineered wood...
- Product-type 9: Fibre, leather, rubber and polymerised materials preservatives
- Product-type 10: Masonry preservatives
- Product-type 11: Preservatives for liquid-cooling and processing systems
- Product-type 12: Slimicides
- Product-type 13: Metalworking-fluid preservatives
MAIN GROUP 3: Pest control
- Product-type 14: Rodenticides
- Product-type 15: AvicideAvicideAn avicide is any substance which can be used to kill birds.Commonly used avicides include strychnine, DRC-1339 and CPTH , and Avitrol . Chloralose is also used as an avicide...
s - Product-type 16: MolluscicideMolluscicideMolluscicides, also known as snail baits and snail pellets, are pesticides against molluscs, which are usually used in agriculture or gardening to control gastropod pests like slugs and snails that can damage crops by feeding on them....
s - Product-type 17: Piscicides
- Product-type 18: InsecticideInsecticideAn insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
s, acaricides and products to control other arthropods - Product-type 19: RepellentRepellentRepellent can refer to:* Insect repellent* Animal repellent...
s and attractants
MAIN GROUP 4: Other biocidal products
- Product-type 20: Preservatives for food or feedstocks
- Product-type 21: Antifouling products
- Product-type 22: EmbalmingEmbalmingEmbalming, in most modern cultures, is the art and science of temporarily preserving human remains to forestall decomposition and to make them suitable for public display at a funeral. The three goals of embalming are thus sanitization, presentation and preservation of a corpse to achieve this...
and taxidermist fluids - Product-type 23: Control of other vertebrates
Current market
The global demand on biocides for use in industrial and consumer goods was estimated at US$6.4 billion in 2008, roughly 3% up from the previous year. Affected by the global economic crisis, the market will remain quite sluggish by 2010. The industry overall is further burdened by ever stricter regulations. The market saw a wave of consolidation in 2008, as producers are looking for measures to control cost and to strengthen market position.Literature
- Wilfried Paulus: Directory of Microbicides for the Protection of Materials and Processes. Springer Netherland, Berlin 2006, ISBN 1-4020-4861-0.
- Danish EPA (2001): Inventory of Biocides used in Denmark