Benzethonium chloride, a synthetic quaternary ammonium salt, is a versatile cationic surfactant and broad-spectrum antimicrobial agent widely used in pharmaceutical, cosmetic, personal care, and industrial fields. In pharmaceuticals, it serves as a key preservative in eye drops, nasal sprays, and topical formulations, preventing microbial contamination and maintaining product stability. It is also an active ingredient in first-aid antiseptics, wound care sprays, and antibacterial ointments, effectively inhibiting bacteria like MRSA, E. coli, and fungi on minor cuts, scrapes, and burns. In cosmetics and personal care, it acts as a preservative and disinfectant in soaps, mouthwashes, anti-itch creams, and antibacterial wipes, ensuring product safety and extending shelf life. Industrially, it functions as a hard-surface disinfectant in food processing plants, a biocide in water treatment, and a phase-transfer catalyst in organic synthesis. Additionally, it is used in electrochemical applications and as a drug delivery carrier due to its surface-active properties. With excellent solubility and stable antimicrobial activity, it remains an essential multifunctional additive across diverse industries.

This substance is classified as GHS05 (Danger) and GHS07 (Warning) with hazard statements H301 (Toxic if swallowed), H314 (Causes severe skin burns and eye damage), and H400 (Very toxic to aquatic life). Inhalation of dust or mist may irritate the respiratory tract, causing coughing, shortness of breath, or throat discomfort. Prolonged or repeated skin contact leads to severe irritation, chemical burns, or allergic dermatitis. Eye contact results in serious corneal injury, redness, pain, or permanent visual impairment. Accidental ingestion causes acute toxicity, including nausea, vomiting, abdominal pain, hypotension, or even respiratory paralysis in severe cases. Chronic exposure may damage the nervous system and internal organs. Handle in well-ventilated fume hoods; wear chemical-resistant gloves, safety goggles, and a dust respirator. In case of skin contact, rinse with plenty of running water for 15 minutes and remove contaminated clothing. If eyes are affected, flush continuously with clean water and seek immediate medical attention. If swallowed, do not induce vomiting; drink large amounts of water and send to hospital promptly. Store separately from strong acids, oxidizing agents, and food; avoid environmental release. Dispose of waste in accordance with local hazardous waste regulations.