Peroxyacetic acid

Description

Since the early 1900s, chlorine has been used as a water disinfectant. It was favored by water and wastewater industries for disinfection until several harmful disinfection by-products were discovered in chlorinated water. Studies were done to find and eliminate disinfection byproduct precursors and look for an alternative disinfectant, which turned out to be peracetic acid, or PAA. Peracetic acid is a chemical product belonging to peroxide compounds such as hydrogen peroxide. However, unlike hydrogen peroxide, it is a more potent antimicrobial agent. Peracetic acid has high germicidal efficiency and sterilizing capability, and its degradation residuals are not dangerous to the environment or toxic to human health. Until 1960, peracetic acid was of special interest to the food processing industry and actually was considered the only agent able to replace glutaraldehyde in the sterilization of surgical, medical, and odontoiatry instruments. The actual core medical applications of peracetic acid are its potent antimicrobial action, also at low temperatures, and the total absence of toxic residuals.

Chemical properties

colourless liquid with an acrid odour

The Uses of Peroxyacetic acid

Environmentally friendly biocide; disinfectant in the food and beverage industry; bleaching agent for textiles and paper. Oxidizing agent in organic synthesis.

The Uses of Peroxyacetic acid

Peroxyacetic acid is used as an epoxidizingagent, for bleaching, as a germicide and fungicide, and in the synthesis of pharmaceuticals.Its solution Dialox is used as a cleansing andsterilizing agent in the reuse of highly permeable dialyzers. Turcic et al. (1997) have reported the efficacy of peroxyacetic acid asa local antiseptic in healing war wounds.Oxidative degradation of polynuclear aromatic hydrocarbons by peroxy acid in contaminated soils has been effectively achieved(N’Guessan et al. 2004).

The Uses of Peroxyacetic acid

This microprocessor-controlled, low-temperature sterilization agent is a strong oxidizing disinfectant against a wide spectrum of antimicrobial activity. Peracetic acid is active against many microorganisms, such as gram-positive and -negative bacteria, fungi, spores, and yeast. This ideal antimicrobial agent is primarily used in food processing and handling as a sanitizer for food contact surfaces. Peracetic acid is also used to disinfect medical supplies and prevent biofilm formation in pulp industries. It can be applied during water purification as a disinfectant and for plumbing disinfection. Peracetic acid is suitable for disinfecting cooling tower water and effectively prevents biofilm formation and controls Legionella bacteria.

Definition

ChEBI: Peracetic acid is a peroxy acid that is acetic acid in which the OH group is substituted by a hydroperoxy group. It is a versatile oxidising agent that is used as a disinfectant. It has a role as an oxidising agent and a disinfectant. It is functionally related to an acetic acid.

Production Methods

Peracetic acid (PAA) is a mixture of acetic acid (CH3COOH) and hydrogen peroxide (H2O2) in an aqueous solution. It is a very strong oxidizing agent and has stronger oxidation potential than chlorine or chlorine dioxide. Liquid, clear, and colorless with no foaming capability. It has a strong pungent acetic acid odor, and the pH is acid . Peracetic acid is produced by reacting acetic acid and hydrogen peroxide. The reaction is allowed to continue for up to 10 days in order to achieve high yields of product. Additional methods of preparation involve the oxidation of acetaldehyde or alternatively as an end product of the reaction of acetic anhydride, hydrogen peroxide, and sulfuric acid. Another method involves the reaction of tetraacetylethylenediamine (TAED) in the presence of an alkaline hydrogen peroxide solution.

General Description

Colorless liquid with a strong, pungent acrid odor. Used as a bactericide and fungicide, especially in food processing; as a reagent in making caprolactam and glycerol; as an oxidant for preparing epoxy compounds; as a bleaching agent; a sterilizing agent; and as a polymerization catalyst for polyester resins.

Air & Water Reactions

Soluble in water

Reactivity Profile

Self-reactive. Peracids should be handled only in small quantities and with extreme care when pure or very concentrated. Organic peracids, such as Peroxyacetic acid, are so unstable that they may explode during distillation, even under reduced pressure [NFPA 1991].

Health Hazard

This is a very toxic compound. The probable human oral lethal dose is 50-500 mg/kg, or between 1 teaspoon and 1 ounce for a 150 pound person.

Health Hazard

The acute toxicity of peracetic acid is low. However, peracids are extremely irritating to the skin, eyes, and respiratory tract. Skin or eye contact with the 40% solution in acetic acid can cause serious burns. Inhalation of high concentrations of mists of peracetic acid solutions can lead to burning sensations, coughing, wheezing, and shortness of breath.
Peracetic acid has not been found to be carcinogenic or to show reproductive or developmental toxicity in humans. There is some evidence that this compound is a weak carcinogen from animal studies (mice).
Data on other peracids suggest peracetic acid may show the worst chronic and acute toxicity of this class of compounds. Other commonly available peracids, such as perbenzoic acid and m-chloroperbenzoic acid (MCPBA) are less toxic, less volatile, and more easily handled than the parent substance.

Health Hazard

Peroxyacetic acid is a severe irritant to theskin and eyes. It can cause severe acid burns.Irritation from 1 mg was severe on rabbits’eyes. Its toxicity is low. The toxicologicalroutes of entry to the body are inhalation,ingestion, and skin contact. The toxicity dataare as follows (NIOSH 1986):LC50 inhalation (rats): 450 mg/m³
LD50 oral (mice): 210 mg/kg
LD50 oral (guinea pigs): 10 mg/kg
Its toxicity in humans should be very low,and a health hazard may arise only fromits severe irritant action. Studies on miceshowed that it caused skin tumors at the siteof application. Its carcinogenicity on humansis not reported. No exposure limit is set forperoxyacetic acid in air.

Fire Hazard

Peracetic acid explodes when heated to 110 °C, and the pure compound is extremely shock sensitive. Virtually all peracids are strong oxidizing agents and decompose explosively on heating. Moreover, most peracids are highly flammable and can accelerate the combustion of other flammable materials if present in a fire. Fires involving peracetic acid can be fought with water, dry chemical, or halon extinguishers. Containers of peracetic acid heated in a fire may explode.

Fire Hazard

Decomposes violently at 230F. When heated to decomposition, Peroxyacetic acid emits acrid smoke and fumes. Runoff to sewer may create a fire or explosion hazard. Powerful oxidizer. Isolate from other stored material, particularly accelerators, oxidizers, and organic or flammable materials. Avoid shock and heat. Hazardous polymerization may not occur.

Flammability and Explosibility

Peracetic acid explodes when heated to 110 °C, and the pure compound is extremely shock sensitive. Virtually all peracids are strong oxidizing agents and decompose explosively on heating. Moreover, most peracids are highly flammable and can accelerate the combustion of other flammable materials if present in a fire. Fires involving peracetic acid can be fought with water, dry chemical, or halon extinguishers. Containers of peracetic acid heated in a fire may explode.

Agricultural Uses

Fungicide, Herbicide, Nematicide, Rodenticide, Microbiocide: This compound is used as bactericide and fungicide, especially in food processing, a reagent in making caprolactam and glycerol; an oxidant for preparing epoxy compounds; a bleaching agent; a sterilizing agent; and a polymerization catalyst for polyester resins. Not approved for use in EU countries. Registered for use in the U.S. and Canada.

Trade name

DESOXON 1®; ESTOSTERIL®; OSBON AC®; OXYMASTER®; PROXITANE®

Safety Profile

Poison by ingestion. Moderately toxic by inhalation and skin contact. A corrosive eye, sktn, and mucous membrane irritant. Questionable carcinogen with experimental tumorigenic data by skin contact. Flammable liquid. Severe explosion hazard when exposed to heat or by spontaneous chemical reaction. Explodes violently at 1 10°C. A powerful oxidizing agent. Explosive reaction with acetic anhydride, 5-p-chlorophenyl-2,2-dimethyl-3hexanone. Violent reaction with ether solvents (e.g., tetrahydrofuran, diethyl ether), metal chloride solutions (e.g., calcium chloride, potassium chloride, sodium chloride), olefins, organic matter. Dangerous; keep away from combustible materials. When heated to decomposition it emits acrid smoke and irritating fumes. To fight fire, use water, foam, CO2. Used as a polymerization initiator, curing agent, and cross-linhng agent. See also PEROXIDES, ORGANIC.

Environmental Fate

Routes and pathways, and relevant physicochemical properties (e.g., solubility, Pow, Henry constant,.)
Melting point ? 0.2 °C.
Log Kow ? 1.07.
Solubility: very soluble in ether, sulfuric acid, and ethanol; miscible with water 1.0 × 10⁶ mg l1 at 25 °C.
Henry’s law constant ? 2.14 × 106 atm-m3 mol1 at 25 °C
Environmental persistency (degradation/speciation)
Peracetic acid is formed naturally in the environment through a series of photochemical reactions involving formaldehyde and photo oxidant radicals. The pKa of peracetic acid is 8.2, indicating that this compound exists partially in anion form in the environment, and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts. It degrades in the environment very quickly but has no potential to bioaccumulate. Its ultimate fate in the environment is in the basic molecules of carbon dioxide, oxygen, and water.
Bioaccumulation and biomagnification
An estimated BCF of 3 was calculated in fish for peracetic acid, using an estimated log Kow of -1.07 and a regression-derived equation. The BCF suggests that the potential for bioconcentration in aquatic organisms is low.

storage

Reactions involving large quantities of peracids should be carried out behind a safety shield. Peracetic acid should be used only in areas free of ignition sources and should be stored in tightly sealed containers in areas separate from oxidizable compounds and flammable substances. Other commonly available peracids, such as perbenzoic acid and m-chloroperbenzoic acid (MCPBA), are less toxic, less volatile, and more easily handled than peracetic acid.

Toxicity evaluation

Peracetic acid kills microorganisms by oxidation and subsequent disruption of their cell membrane via the hydroxyl radical. Because diffusion is slower than the half-life of the radical, it will react with any oxidizable compound in its vicinity. Peracetic acid, also, is not deactivated by catalase and peroxidase enzymes produced by microorganisms. Therefore, it can damage virtually all types of macromolecules associated with a microorganism, such as carbohydrates, nucleic acids, lipids, and amino acids. The mechanism of oxidation is the transfer of electrons; therefore, the stronger the oxidizer will produce faster and ultimately leads to cell lyse and true microbial death.

Incompatibilities

Peracids such as peracetic acid are strong oxidizing agents and react exothermically with easily oxidized substrates. In some cases the heat of reaction can be sufficient to induce ignition, at which point combustion is accelerated by the presence of the peracid. Violent reactions may potentially occur, for example, with ethers, metal chloride solutions, olefins, and some alcohols and ketones. Shock-sensitive peroxides may be generated by the action of peracids on these substances as well as on carboxylic anhydrides. Some metal ions, including iron, copper, cobalt, chromium, and manganese, may cause runaway peroxide decomposition. Peracetic acid is also reportedly sensitive to light.

Waste Disposal

Excess peracetic acid and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines. Peracids may be incompatible with other flammable mixed chemical waste; for example, shock-sensitive peroxides can be generated by reaction with some ethers such as THF and diethyl ether.