The alcohol must be diluted with water for the optimum effect, as proteins are not denatured as readily with straight alcohol. Alcohol is also effective in inhibiting spore germination by affecting the enzymes necessary for germination. Chlorine is a very common disinfectant used in a wide variety of cleaning solutions and applications — even in drinking water — because, even in very small amounts, it exhibits fast bactericidal action.
Chlorine works by oxidizing proteins, lipids and carbohydrates. Hypochlorous acid, which is a weak acid that forms when chlorine is dissolved in water, has the most effect on the bacterial cell, targeting some key metabolic enzymes and destroying the organism. Chlorine compounds have also been shown to affect surface antigen in enveloped viruses and deoxyribonucleic acid DNA as well as structural alterations in non-enveloped viruses. Very few chemicals are considered sporicidal; however, chlorine compounds in higher concentrations have been shown to kill bacterial spores such as Clostridium difficile C.
Both hydrogen peroxide and peracetic acid are peroxygen compounds of great importance in infection control because, unlike like most disinfectants, they are unaffected by the addition of organic matter and salts. In addition, the formation of the hydroxyl radical, a highly reactive ion that occurs as peroxygen compounds encounter air, is lethal to many species of bacteria because it is a strong oxidant.
Being highly reactive, the hydroxyl radical attacks essential cell components and cell membranes, causing them to collapse. Peroxygen compounds also kill spores by removing proteins from the spore coat, exposing its core to the lethal disinfectant. Phenol and its derivatives exhibit several types of bactericidal action. At higher concentrations, the compounds penetrate and disrupt the cell wall and make the cell proteins fall out of suspension.
One of the first things to occur is stopping essential enzymes. The mucin-loop test is a severe test developed to produce long survival times. Thus, these figures should not be extrapolated to the exposure times needed when these germicides are used on medical or surgical material Alcohols are not recommended for sterilizing medical and surgical materials principally because they lack sporicidal action and they cannot penetrate protein-rich materials. Fatal postoperative wound infections with Clostridium have occurred when alcohols were used to sterilize surgical instruments contaminated with bacterial spores Alcohols have been used effectively to disinfect oral and rectal thermometers , , hospital pagers , scissors , and stethoscopes Alcohols have been used to disinfect fiberoptic endoscopes , but failure of this disinfectant have lead to infection , Alcohol towelettes have been used for years to disinfect small surfaces such as rubber stoppers of multiple-dose medication vials or vaccine bottles.
Furthermore, alcohol occasionally is used to disinfect external surfaces of equipment e. In contrast, three bloodstream infection outbreaks have been described when alcohol was used to disinfect transducer heads in an intensive-care setting The documented shortcomings of alcohols on equipment are that they damage the shellac mountings of lensed instruments, tend to swell and harden rubber and certain plastic tubing after prolonged and repeated use, bleach rubber and plastic tiles and damage tonometer tips by deterioration of the glue after the equivalent of 1 working year of routine use Tonometer biprisms soaked in alcohol for 4 days developed rough front surfaces that potentially could cause corneal damage; this appeared to be caused by weakening of the cementing substances used to fabricate the biprisms Corneal opacification has been reported when tonometer tips were swabbed with alcohol immediately before measurement of intraocular pressure Alcohols are flammable and consequently must be stored in a cool, well-ventilated area.
They also evaporate rapidly, making extended exposure time difficult to achieve unless the items are immersed. Hypochlorites, the most widely used of the chlorine disinfectants, are available as liquid e. The most prevalent chlorine products in the United States are aqueous solutions of 5. They have a broad spectrum of antimicrobial activity, do not leave toxic residues, are unaffected by water hardness, are inexpensive and fast acting , remove dried or fixed organisms and biofilms from surfaces , and have a low incidence of serious toxicity Sodium hypochlorite at the concentration used in household bleach 5.
The microbicidal activity of chlorine is attributed largely to undissociated hypochlorous acid HOCl. A potential hazard is production of the carcinogen bis chloromethyl ether when hypochlorite solutions contact formaldehyde and the production of the animal carcinogen trihalomethane when hot water is hyperchlorinated After reviewing environmental fate and ecologic data, EPA has determined the currently registered uses of hypochlorites will not result in unreasonable adverse effects to the environment Alternative compounds that release chlorine and are used in the health-care setting include demand-release chlorine dioxide, sodium dichloroisocyanurate, and chloramine-T.
The advantage of these compounds over the hypochlorites is that they retain chlorine longer and so exert a more prolonged bactericidal effect. Sodium dichloroisocyanurate tablets are stable, and for two reasons, the microbicidal activity of solutions prepared from sodium dichloroisocyanurate tablets might be greater than that of sodium hypochlorite solutions containing the same total available chlorine.
Second, solutions of sodium dichloroisocyanurate are acidic, whereas sodium hypochlorite solutions are alkaline, and the more microbicidal type of chlorine HOCl is believed to predominate Chlorine dioxide-based disinfectants are prepared fresh as required by mixing the two components base solution [citric acid with preservatives and corrosion inhibitors] and the activator solution [sodium chlorite].
In vitro suspension tests showed that solutions containing about ppm chlorine dioxide achieved a reduction factor exceeding 10 6 of S. The potential for damaging equipment requires consideration because long-term use can damage the outer plastic coat of the insertion tube In another study, chlorine dioxide solutions at either ppm or 30 ppm killed Mycobacterium avium-intracellulare within 60 seconds after contact but contamination by organic material significantly affected the microbicidal properties The main products of this water are hypochlorous acid e.
As with any germicide, the antimicrobial activity of superoxidized water is strongly affected by the concentration of the active ingredient available free chlorine One manufacturer generates the disinfectant at the point of use by passing a saline solution over coated titanium electrodes at 9 amps.
The product generated has a pH of 5. Although superoxidized water is intended to be generated fresh at the point of use, when tested under clean conditions the disinfectant was effective within 5 minutes when 48 hours old Unfortunately, the equipment required to produce the product can be expensive because parameters such as pH, current, and redox potential must be closely monitored. The solution is nontoxic to biologic tissues. Although the United Kingdom manufacturer claims the solution is noncorrosive and nondamaging to endoscopes and processing equipment, one flexible endoscope manufacturer Olympus Key-Med, United Kingdom has voided the warranty on the endoscopes if superoxidized water is used to disinfect them As with any germicide formulation, the user should check with the device manufacturer for compatibility with the germicide.
Additional studies are needed to determine whether this solution could be used as an alternative to other disinfectants or antiseptics for hand washing, skin antisepsis, room cleaning, or equipment disinfection e. The exact mechanism by which free chlorine destroys microorganisms has not been elucidated. Inactivation by chlorine can result from a number of factors: oxidation of sulfhydryl enzymes and amino acids; ring chlorination of amino acids; loss of intracellular contents; decreased uptake of nutrients; inhibition of protein synthesis; decreased oxygen uptake; oxidation of respiratory components; decreased adenosine triphosphate production; breaks in DNA; and depressed DNA synthesis , The actual microbicidal mechanism of chlorine might involve a combination of these factors or the effect of chlorine on critical sites Low concentrations of free available chlorine e.
Higher concentrations 1, ppm of chlorine are required to kill M. One study reported that 25 different viruses were inactivated in 10 minutes with ppm available chlorine Several studies have demonstrated the effectiveness of diluted sodium hypochlorite and other disinfectants to inactivate HIV Chlorine ppm showed inhibition of Candida after 30 seconds of exposure Because household bleach contains 5.
A chlorine dioxide generator has been shown effective for decontaminating flexible endoscopes but it is not currently FDA-cleared for use as a high-level disinfectant Chlorine dioxide can be produced by mixing solutions, such as a solution of chlorine with a solution of sodium chlorite In , a chlorine dioxide product was voluntarily removed from the market when its use caused leakage of cellulose-based dialyzer membranes, which allowed bacteria to migrate from the dialysis fluid side of the dialyzer to the blood side However, the biocidal activity of this disinfectant decreased substantially in the presence of organic material e.
No bacteria or viruses were detected on artificially contaminated endoscopes after a 5-minute exposure to superoxidized water and HBV-DNA was not detected from any endoscope experimentally contaminated with HBV-positive mixed sera after a disinfectant exposure time of 7 minutes Hypochlorites are widely used in healthcare facilities in a variety of settings. A — dilution of 5. For small spills of blood i. Because hypochlorites and other germicides are substantially inactivated in the presence of blood 63, , , , large spills of blood require that the surface be cleaned before an EPA-registered disinfectant or a final concentration solution of household bleach is applied If a sharps injury is possible, the surface initially should be decontaminated 69, , then cleaned and disinfected final concentration Extreme care always should be taken to prevent percutaneous injury.
At least ppm available chlorine for 10 minutes is recommended for decontaminating CPR training manikins Full-strength bleach has been recommended for self-disinfection of needles and syringes used for illicit-drug injection when needle-exchange programs are not available. The difference in the recommended concentrations of bleach reflects the difficulty of cleaning the interior of needles and syringes and the use of needles and syringes for parenteral injection Clinicians should not alter their use of chlorine on environmental surfaces on the basis of testing methodologies that do not simulate actual disinfection practices , Other uses in healthcare include as an irrigating agent in endodontic treatment and as a disinfectant for manikins, laundry, dental appliances, hydrotherapy tanks 23, 41 , regulated medical waste before disposal , and the water distribution system in hemodialysis centers and hemodialysis machines Chlorine long has been used as the disinfectant in water treatment.
Water disinfection with monochloramine by municipal water-treatment plants substantially reduced the risk for healthcare—associated Legionnaires disease , Chlorine dioxide also has been used to control Legionella in a hospital water supply. Thus, if a user wished to have a solution containing ppm of available chlorine at day 30, he or she should prepare a solution containing 1, ppm of chlorine at time 0. Sodium hypochlorite solution does not decompose after 30 days when stored in a closed brown bottle The use of powders, composed of a mixture of a chlorine-releasing agent with highly absorbent resin, for disinfecting spills of body fluids has been evaluated by laboratory tests and hospital ward trials.
The inclusion of acrylic resin particles in formulations markedly increases the volume of fluid that can be soaked up because the resin can absorb — times its own weight of fluid, depending on the fluid consistency.
One problem with chlorine-releasing granules is that they can generate chlorine fumes when applied to urine Formaldehyde is used as a disinfectant and sterilant in both its liquid and gaseous states. Liquid formaldehyde will be considered briefly in this section, and the gaseous form is reviewed elsewhere In-depth knowledge of disinfection and sterilization is a key component of infection control.
Sterilization completely removes a spore, whereas disinfection cannot. Disinfectants are classified as oxidants and non-oxidants. The decision regarding which method to apply is based on Spaulding's classification. In this article, disinfection and sterilization are thoroughly reviewed, and extensive information from basic to practical points is discussed.
The main purpose of infection control can be briefly summarized as blocking the transmission of microorganisms or pathogens [ 1 ]. Blocking should be performed in two directions. The first is prevention of vertical transmission, and the other is prevention of horizontal or lateral transmission.
Vertical transmission is the propagation of pathogens from generation to generation. Proper use and regulation of antibiotics is essential to prevent vertical transmission, requiring antibiotic stewardship. Lateral transmission is the transfer of resistance of a pathogen to other pathogens of the same generation, or propagation and expansion of the pathogen into its surroundings [ 2 ]. Preventing this lateral transmission to the greatest extent possible is a practical point in terms of infection control.
Knowledge of disinfection or antisepsis and sterilization is required for these measures [ 3 , 4 , 5 , 6 , 7 ]. Doctors specializing in infection control who serve as medical directors have a solid knowledge of pathogens or antibiotics, but less knowledge of or interest in disinfection or sterilization. Therefore, the purpose of this paper is to investigate in detail sterilization and disinfection techniques to which less attention has been paid, starting with the basic knowledge.
Both disinfection and sterilization remove pathogens. The key to distinguishing the two techniques is the endospore. Removing pathogens but leaving endospores is considered disinfection, while completely destroying both endospores and pathogens is considered sterilization [ 3 ]. Therefore, it is necessary to understand when it is appropriate to apply disinfection or sterilization. What is this basic knowledge for?
Disinfection and sterilization occur at the molecular level. Disinfection and sterilization require electrons for oxidation, acidification, and coagulation. Therefore, basic knowledge of atomic number and electrons is required.
Atoms have protons with a positive charge and neutrons in the nucleus, and the same number of electrons with a negative charge as that of protons orbit in the outer shell. Electrons, however, do not have a fixed orbit.
Electrons are located somewhere in a cloudy space, with a possibility of being located within the space surrounding the nucleus of the particular atom.
An atom possessing the same number of electrons as that of protons is based on the premise that the atoms are not ionized. The number of protons is the atomic number.
The mass number is the sum of the number of protons and the number of neutrons. The number of protons and the number of neutrons is not always the same. An element with a different number of protons and neutrons is an isotope. For example, C has an atomic number of 12 12 C , which is common, but it also has an atomic number of 14 14 C , with two more neutrons. It is necessary to know how each atom acts in disinfection and sterilization.
The ion is a state in which the number of electrons is not equal to the number of protons in an element. This phenomenon occurs because the valence shell of the atom is only stabilized at the energy level in which it is filled with eight electrons octet rule. Therefore, the atom releases the remaining electrons or takes the missing electrons to fill the valence shell with eight electrons. When an atom loses one of the outermost electrons, the number of protons becomes greater than that of electrons.
Therefore, the net charge becomes positive, and the element is called a cation. In the periodic table, atoms belonging to group 1 are representative examples. Na and K have only one outer shell electron; thus, for these elements, it is much more natural to lose one electron rather than to take seven electrons.
On the other hand, when an element takes one outer shell electron, the number of electrons becomes greater than that of protons. Therefore, the net charge becomes negative, and the element is called an anion. A representative example is a halogen belonging to group 17 in the periodic table, which is described below.
Oxidation refers to the action of taking electrons. Substances that take electrons from an element are oxidants. Reduction refers to the opposite action. Oxidation and reduction are two important mechanisms in disinfectants and sterilants, and details of each formulation are discussed later in the sections on classification and mechanisms of disinfectants and sterilants.
A considerable number of disinfectants contain halogens, especially chlorine Cl. As halogens comprise a large proportion of disinfectants, it is worthwhile to know the nature of these elements. It is also to understand the mechanisms of disinfection and sterilization by oxidation. In the term halogen, hal means sea water or salt, and gen means production.
That is, halogen denotes substances that produce salts. Fluorine F , chlorine Cl , and iodine I are the main halogens in the disinfection category. Fluorine means fluere in Latin and flow in English. Chlorine means greenish-yellow color in Greek, and this name is given because the color of the chlorine gas is yellow. Iodine means violet color in Greek. Because halogens belong to the periodic table group 17, seven of the eight outer shell electron positions in halogen are occupied, and only one remains.
Therefore, taking only one electron from another element and filing the remaining space leads to compliance with the octet rule. To accomplish this, halogens select one of two methods:. The easiest elements from which halogens can take electrons are metals belonging to group 1, such as Na and K, which have only one electron in the outer shell. Therefore, when halogens encounter these metals, they immediately take the electrons to make salts such as NaCl and KI.
How do halogens appear in our eyes? The locations where halogens are in contact crackle into fire. For example, if an unfortunate situation is caused by an individual breathing in chlorine gas, the palate, airway, esophagus, and lower respiratory mucus are instantly eroded and destroyed.
In other words, halogens are poison gases. The first chemical weapon in history of war was the chlorine gas used by France and Germany in the First World War. When chlorine becomes an anion, it is chloride Cl - , and it is inactive because it has become a stable element conforming to the octet rule by taking a single electron.
Halogens are very strong oxidizing substances that indiscriminately destroy the cellular protein, nucleic acid, and cell wall or membrane of microorganisms.
Halogens perform disinfection through disruption of oxidative phosphorylation, which is the most important process in cell survival. It is necessary to understand the mechanism of disinfection by oxidation. However, contrary to this common perception, oxygen is not a very favorable element in nature for living organisms.
Oxygen did not exist on Earth from the beginning. Thus, following the initial appearance of oxygen on Earth, almost all living organisms performing anaerobic metabolism became extinct, and living organisms that benefited from oxygen survived.
Those that survived were aerobic bacteria, some of which moved into other eukaryotes and became mitochondria or chloroplasts. When oxygen enters the mitochondria, it is processed there instead of in the host cell, turned by the mitochondria into water, with simultaneous production of adenosine triphosphate ATP in large quantities.
This procedure is known as respiration or oxidative phosphorylation. However, reduction of oxygen does not happen at once, but requires several steps, with acceptance of one electron at a time.
Correspondingly, electrons are not paired and are left alone several times. When the electrons do not pair, they become very unstable at the energy level, and as a result, the molecules become very violent, radically moving for pairing.
These molecules are so-called radicals. If this definition is applied broadly, halogens can also be regarded as radicals. In the oxygen reduction process respiration , superoxide anions are produced in the first stage, peroxide is produced in the second stage, and hydroxyl radicals are produced in the third stage [ 8 , 9 ], all of which are very rampant. In other words, when any element comes near these, the radicals wildly take electrons from the element.
For example, if the subject is a microorganism, disinfection and sterilization occur immediately. Spore is not a precise term. Instead, endospore is the appropriate word. Endospore is the decisive factor that distinguishes disinfection from sterilization, because sterilization must kill the endospore [ 3 , 10 ].
In the s, scientists began experimenting with a variety of chemicals for disinfection. In the s, British surgeon Joseph Lister — began using carbolic acid, known as phenol , as a disinfectant for the treatment of surgical wounds see Foundations of Modern Cell Theory. Today, carbolic acid is no longer used as a surgical disinfectant because it is a skin irritant, but the chemical compounds found in antiseptic mouthwashes and throat lozenges are called phenolics.
Chemically, phenol consists of a benzene ring with an —OH group, and phenolics are compounds that have this group as part of their chemical structure. Phenolics such as thymol and eucalyptol occur naturally in plants. Other phenolics can be derived from creosote, a component of coal tar. Phenolics tend to be stable, persistent on surfaces, and less toxic than phenol.
They inhibit microbial growth by denaturing proteins and disrupting membranes. Figure 1. Phenol and phenolic compounds have been used to control microbial growth. Phenolics like cresols methylated phenols and o-phenylphenol were active ingredients in various formulations of Lysol since its invention in The bisphenol hexachlorophene , a disinfectant, is the active ingredient in pHisoHex, a topical cleansing detergent widely used for handwashing in hospital settings.
Triclosan is another bisphenol compound that has seen widespread application in antibacterial products over the last several decades. Initially used in toothpastes, triclosan is now commonly used in hand soaps and is frequently impregnated into a wide variety of other products, including cutting boards, knives, shower curtains, clothing, and concrete, to make them antimicrobial.
It is particularly effective against gram-positive bacteria on the skin, as well as certain gram-negative bacteria and yeasts. But are the antibacterial ingredients in these products really safe and effective? Although the use of triclosan in the home increased dramatically during the s, more than 40 years of research by the FDA have turned up no conclusive evidence that washing with triclosan-containing products provides increased health benefits compared with washing with traditional soap.
In short, soaps with triclosan may remove or kill a few more germs but not enough to reduce the spread of disease. Perhaps more disturbing, some clear risks associated with triclosan-based soaps have come to light. The widespread use of triclosan has led to an increase in triclosan-resistant bacterial strains, including those of clinical importance, such as Salmonella enterica ; this resistance may render triclosan useless as an antibacterial in the long run.
Other disinfectants with a less specific mode of action are much less prone to engendering resistance because it would take much more than a single genetic change. Use of triclosan over the last several decades has also led to a buildup of the chemical in the environment. Triclosan in hand soap is directly introduced into wastewater and sewage systems as a result of the handwashing process. There, its antibacterial properties can inhibit or kill bacteria responsible for the decomposition of sewage, causing septic systems to clog and back up.
Eventually, triclosan in wastewater finds its way into surface waters, streams, lakes, sediments, and soils, disrupting natural populations of bacteria that carry out important environmental functions, such as inhibiting algae.
Triclosan also finds its way into the bodies of amphibians and fish, where it can act as an endocrine disruptor. Detectable levels of triclosan have also been found in various human bodily fluids, including breast milk, plasma, and urine. In December , the FDA gave soap manufacturers until to prove that antibacterial soaps provide a significant benefit over traditional soaps; if unable to do so, manufacturers will be forced to remove these products from the market.
Figure 2. Triclosan is a common ingredient in antibacterial soaps despite evidence that it poses environmental and health risks and offers no significant health benefit compared to conventional soaps. Some of the first chemical disinfectants and antiseptics to be used were heavy metals. Heavy metals kill microbes by binding to proteins, thus inhibiting enzymatic activity. Heavy metals are oligodynamic, meaning that very small concentrations show significant antimicrobial activity.
Ions of heavy metals bind to sulfur-containing amino acids strongly and bioaccumulate within cells, allowing these metals to reach high localized concentrations.
This causes proteins to denature. Heavy metals are not selectively toxic to microbial cells. They may bioaccumulate in human or animal cells, as well, and excessive concentrations can have toxic effects on humans.
If too much silver accumulates in the body, for example, it can result in a condition called argyria , in which the skin turns irreversibly blue-gray. One way to reduce the potential toxicity of heavy metals is by carefully controlling the duration of exposure and concentration of the heavy metal. Figure 3. Heavy metals denature proteins, impairing cell function and, thus, giving them strong antimicrobial properties.
Fred and Hendrik A. Mercury is an example of a heavy metal that has been used for many years to control microbial growth. It was used for many centuries to treat syphilis. Mercury compounds like mercuric chloride are mainly bacteriostatic and have a very broad spectrum of activity. Various forms of mercury bind to sulfur-containing amino acids within proteins, inhibiting their functions.
It is toxic to the central nervous, digestive, and renal systems at high concentrations, and has negative environmental effects, including bioaccumulation in fish. Topical antiseptics such as mercurochrome , which contains mercury in low concentrations, and merthiolate , a tincture a solution of mercury dissolved in alcohol were once commonly used.
However, because of concerns about using mercury compounds, these antiseptics are no longer sold in the United States. Silver has long been used as an antiseptic.
In ancient times, drinking water was stored in silver jugs. Silver nitrate drops were once routinely applied to the eyes of newborns to protect against ophthalmia neonatorum , eye infections that can occur due to exposure to pathogens in the birth canal, but antibiotic creams are more now commonly used. Silver is often combined with antibiotics, making the antibiotics thousands of times more effective. Several other heavy metals also exhibit antimicrobial activity.
Copper sulfate is a common algicide used to control algal growth in swimming pools and fish tanks. The use of metallic copper to minimize microbial growth is also becoming more widespread. Copper linings in incubators help reduce contamination of cell cultures. The use of copper pots for water storage in underdeveloped countries is being investigated as a way to combat diarrheal diseases. Copper coatings are also becoming popular for frequently handled objects such as doorknobs, cabinet hardware, and other fixtures in health-care facilities in an attempt to reduce the spread of microbes.
Nickel and zinc coatings are now being used in a similar way. Other forms of zinc, including zinc chloride and zinc oxide , are also used commercially. Zinc chloride is quite safe for humans and is commonly found in mouthwashes, substantially increasing their length of effectiveness. Zinc oxide is found in a variety of products, including topical antiseptic creams such as calamine lotion, diaper ointments, baby powder, and dandruff shampoos. Other chemicals commonly used for disinfection are the halogens iodine , chlorine , and fluorine.
Iodine works by oxidizing cellular components, including sulfur-containing amino acids, nucleotides, and fatty acids, and destabilizing the macromolecules that contain these molecules. It is often used as a topical tincture, but it may cause staining or skin irritation.
One common iodophor is povidone-iodine , which includes a wetting agent that releases iodine relatively slowly. Figure 4. Chlorine is another halogen commonly used for disinfection. When chlorine gas is mixed with water, it produces a strong oxidant called hypochlorous acid, which is uncharged and enters cells easily.
Chlorine gas is commonly used in municipal drinking water and wastewater treatment plants, with the resulting hypochlorous acid producing the actual antimicrobial effect. Those working at water treatment facilities need to take great care to minimize personal exposure to chlorine gas. Sodium hypochlorite is the chemical component of common household bleach , and it is also used for a wide variety of disinfecting purposes. Hypochlorite salts, including sodium and calcium hypochlorites, are used to disinfect swimming pools.
Chlorine gas, sodium hypochlorite, and calcium hypochlorite are also commonly used disinfectants in the food processing and restaurant industries to reduce the spread of foodborne diseases. Workers in these industries also need to take care to use these products correctly to ensure their own safety as well as the safety of consumers.
A recent joint statement published by the Food and Agriculture Organization FAO of the United Nations and WHO indicated that none of the many beneficial uses of chlorine products in food processing to reduce the spread of foodborne illness posed risks to consumers. Another class of chlorinated compounds called chloramines are widely used as disinfectants. Chloramines are relatively stable, releasing chlorine over long periods time. Chloramines are derivatives of ammonia by substitution of one, two, or all three hydrogen atoms with chlorine atoms.
Figure 5. Monochloroamine, one of the chloramines, is derived from ammonia by the replacement of one hydrogen atom with a chlorine atom.
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