Benzalkonium chloride

Benzalkonium chloride (BAC) is a compound of the class of quaternary ammonium compounds (QAC) used as a cationic surfactant in personal hygiene, cosmetic and skin disinfection products. BAC is a mixture of alkylbenzyldimethylammonium chlorides [C6H5CH2N(CH3)2RCl], in which R = C12, C14, C16, C18 are the main compounds, and the antibacterial effects being given by the alkyl chain length and the quaternary ammonium groups.

Benzalkonium chloride is a quaternary ammonium antiseptic and disinfectant with actions and uses similar to those of other cationic surfactants. It is also used as an antimicrobial preservative for pharmaceutical products. For most multidose aqueous nasal, ophthalmic and otic products, benzalkonium chloride is the preservative of choice. It has been used in eye drops as a preservative since the 1950’s and it is still the most common preservative used in ophthalmic solutions at a concentration of 0.01–0.02%. It is an effective bactericidal and fungicidal agent that helps to minimise the growth of organisms in multidose containers.

Benzalkonium chloride is a cationic detergent, like other quaternary ammonium compounds, and is used as an antiseptic agent in ophthalmic preparations, skin disinfectants, cosmetics, deodorants, mouthwashes, lozenges and solutions for contact lenses. It is also used in medications for relief of burns, scalds, cuts and local inflammation of the skin and mouth. It may also be used for infant teething and in wipes for usage for irritations around the anus. Further research may identify additional product or industrial usages of this chemical.

benzalkonium chloride appears to be the main preservative in ophthalmic preparations on the EU market, approximately 74% of ophthalmic preparations contain benzalkonium chloride as a preservative. Benzalkonium chloride is further used as a preservative in more than 200 medicinal products for the nasal route of administration and about 10 preparations for inhalation use are authorised on EU markets based on the additional survey performed amongst a limited number of member states. Only a few medicinal products containing benzalkonium chloride are intended for other routes of administrations i.e. cutaneous, oral, oromucosal, rectal, vaginal and parenteral use.

Benzalkonium chloride is often used in non-alcohol-based hand sanitisers. It has some effectivity against bacteria and limited activity against viruses. It’s also slow to act, meaning that non-alcohol-based sanitisers are generally less effective than alcohol-based ones. The CDC states that the available evidence is that benzalkonium chloride is not as effective against coronavirus as alcohols. CDC does not have a recommended alternative to hand rub products with greater than 60% ethanol or 70% isopropanol as active ingredients.

Repeated dose oral toxicity studies have shown that within 2 days of dosing benzalkonium chloride is lethal in mice and rats at concentrations of approximately 500 mg/kg/day (dietary administration) and above due to local effects in the gastrointestinal (GI) tract. However, no organ-specific toxicity was observed in these two species at concentrations below those causing direct effects on the GI tract. Results of 90-day and chronic toxicity studies have only shown changes in body weight and other general responses.
Substantial literature data indicate that benzalkonium chloride may induce ocular damage. In vivo studies have been mainly performed in rabbits and, therefore, careful extrapolation to humans is required due to the differences between these two species. A recent study of the toxicity of ophthalmological solutions containing 0.005% and 0.01% of benzalkonium chloride applied twice daily in rabbits and monkeys for up to 52 weeks did not show ophthalmological changes of irritation or corneal damage.
In vitro studies have suggested that benzalkonium chloride (0.001–0.05%) may cause ciliary beat stasis as well as nasal lesions in rats when applied eight times daily.
Available experimental data indicate that benzalkonium chloride is neither genotoxic nor carcinogenic nor a reproductive toxicant.

Benzethonium chloride appears as odorless white crystals or powder with a very bitter taste. A 1% solution in water is slightly alkaline to litmus.

Benzalkonium chloride is a highly concentrated quaternary ammonium antimicrobial used in a broad number of applications.
Benzalkonium chloride (BAK) is a common preservative used in ophthalmic medications and is the active ingredient in some skin disinfectants and hand sanitizers. BAK is known to be effective in killing bacteria and enveloped viruses. However, its activity against non-enveloped viruses is unknown.
Benzalkonium chloride (as Roccal or Zephiran) was found to inactivate influenza, measles, canine distemper, rabies, fowl laryngotracheitis, vaccinia, Semliki Forest, feline pneumonitis, meningopneumonitis, and herpes simplex viruses after 10 min of exposure at 30 C or at room temperature. Poliovirus and encephalomyocarditis virus were not inactivated under the same conditions.
Benzalkonium chloride is also used as a topical anti-infective in medicine as well as a germicide for cleansing food and dairy utensils, and as a controlling agent for swimming pool algae. It is also an additive in deodorants and hairdressing preparations.

Benzalkonium chloride is a quaternary ammonium detergent that treats grampositive and gram-negative organisms. Strains of Mycobacterium tuberculosis and Pseudomonas aeruginosa are often resistant. It is not effective against spore-forming organisms. It is nonirritating to mucous membranes and may be used near the eyes. Drawbacks include lack of sustained activity and ease of contamination of this antimicrobial. It is inactivated by anionic compounds such as soap. A 0.1% solution takes 7 minutes to decrease the bacterial count by 50%. All traces of soap must be removed with 70% alcohol before use.

Benzalkonium chloride, a quaternary ammonium compound, is found as a preservative in contact lens cleaning solutions, soaps, and skin care products and is used as a disinfectant and impregnated on medical devices to prevent bacterial colonization. Localized Cou has been described to cutaneous contact with a toilet cleaner.Parenteral and mucosal exposure has been documented to result in a generalized urticaria, respiratory compromise, and anaphylaxis. It was used as a preservative in bronchodilator nebulizer solutions; however, it was proven to cause bronchoconstriction in some asthmatic patients and a call for its withdrawal from these products occurred in 2001.Whether these effects are related to an IgE-mediated mechanism has not been established.
Bernstein et al. describe a case of combined occupational asthma and localized and generalized Cou to contact with benzalkonium chloride in a toilet cleaner. They could not show benzalkonium chloride-specific IgE antibodies in the serum of this patient.
Benzalkonium chloride in nasal drops,eye drops,nebulizer solution,and a benzalkonium-coated central venous catheter have been documented to cause immediate generalized reactions and anaphylaxis.

This cationic surface-active disinfectant and preservative (FWlauryl-homologue = 340.00 g/mol; CAS 8001-54-5; Soluble in Ethanol and Acetone), also named alkyldimethylbenzyl-ammonium chloride, refers to several cationic detergents that are widely used in various pharmaceutical preparations, including eye, ear, and nasal drops as well as leave-on antiseptics. (See also specific agent) Benzalkonium chloride has also been used in the isolation and purification of proteins and as an antimicrobial agent. Commercial sources typically contain a mixture of alkyl homologues, predominantly with a dodecyl (lauryl) side-chain. Standard concentrates are manufactured as 50% and 80% w/w solutions, and sold under trade names such as BC50, BC80, BAC50, and BAC80. Target (s) : acetylcholinesterase, esterase activity; butyrylcholinesterase, esterase activity (but activates the aryl acylamidase activity); trypsin; chymotrypsin; histamine release; G proteins ; serralysin; chitosanase.