Benzalkonium chloride
[CAS# 8001-54-5]

Identification

• Classification: Surfactant >> Cationic surfactant >> Quaternary ammonium salt type
• Name: Benzalkonium chloride
• Synonyms: Benzalkonium (C8-C16) chloride
• CAS Registry Number: 8001-54-5 (8045-21-4)
• EC Number: 616-786-9
• SMILES: CCCCCCCCCCCC[N+](C)(C)CC1=CC=CC=C1.[Cl-]

Properties

• Density: 0.98

Safety Data

• Hazard Symbols: GHS05;GHS07;GHS09 Danger
• Risk Statements: H302+H332-H302-H312-H314-H318-H400-H410
• Safety Statements: P260-P264-P264+P265-P270-P273-P280-P301+P317-P301+P330+P331-P302+P352-P302+P361+P354-P304+P340-P305+P354+P338-P316-P317-P321-P330-P362+P364-P363-P391-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin corrosion	Skin Corr.	1B	H314
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H302
Serious eye damage	Eye Dam.	1	H318
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Acute toxicity	Acute Tox.	4	H332
Acute toxicity	Acute Tox.	3	H311
Acute toxicity	Acute Tox.	3	H301
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Acute toxicity	Acute Tox.	2	H330
Skin corrosion	Skin Corr.	1	H314
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Acute toxicity	Acute Tox.	1	H301
Skin corrosion	Skin Corr.	1A	H314
Skin irritation	Skin Irrit.	2	H315

Discovery and Applications

Benzalkonium chloride, a quaternary ammonium compound, is widely recognized for its antimicrobial properties and versatility as a disinfectant and preservative. Its discovery dates back to the early 20th century, around the 1930s, when it was first synthesized as a component of various disinfecting formulations. The compound is produced through the reaction of benzyl chloride with a mixture of long-chain alkyl amines, resulting in a product with both hydrophobic and hydrophilic characteristics, making it effective in a variety of applications.

One of the primary applications of benzalkonium chloride is in the field of healthcare as a disinfectant and antiseptic. It is used in hospitals and clinical settings to sanitize surfaces, medical equipment, and instruments due to its efficacy against a broad spectrum of bacteria, viruses, and fungi. Its ability to disrupt microbial cell membranes makes it a potent agent in preventing infections, particularly in settings where hygiene is critical.

In addition to its use in healthcare, benzalkonium chloride is commonly found in personal care products, including cosmetics, shampoos, and lotions. It serves as a preservative, helping to extend the shelf life of these products by preventing the growth of microorganisms. Its emulsifying properties also contribute to the stability and texture of formulations, enhancing the overall consumer experience.

Benzalkonium chloride is also utilized in industrial applications, including as a biocide in water treatment systems. It effectively controls microbial growth in cooling towers, swimming pools, and other water systems, ensuring safe and clean water for various uses. Moreover, it is incorporated into formulations for disinfecting wipes and sprays, offering convenience and effectiveness in household cleaning.

Despite its widespread use, the safety of benzalkonium chloride has been a topic of discussion. While it is generally regarded as safe when used as directed, concerns have arisen regarding potential skin irritation and allergic reactions in some individuals. Regulatory agencies have established guidelines to ensure safe concentrations in consumer products, thereby mitigating risks.

Research continues to explore the potential of benzalkonium chloride in various fields, including its application in drug delivery systems and as a component in antimicrobial coatings. The compound's unique properties position it as a valuable agent in the ongoing development of effective antimicrobial solutions.

In summary, benzalkonium chloride is a versatile quaternary ammonium compound with significant applications in healthcare, personal care products, and industrial settings. Its discovery marked a pivotal advancement in antimicrobial agents, contributing to improved hygiene and safety in various environments.

References

2024. Microbial biofilm metabolization of benzalkonium compounds (benzyl dimethyl dodecyl ammonium & benzyl dimethyl tetradecyl ammonium chloride). Journal of Hazardous Materials, 463.
DOI: 10.1016/j.jhazmat.2023.132834

2023. Determination of 25 quaternary ammonium compounds in sludge by liquid chromatography-mass spectrometry. Analytical Sciences, 39(8).
DOI: 10.1007/s44211-023-00354-0