Research and Testing Results on the Ability of Certain Compounds to Reduce CS Gas Skin Irritation in Rabbits

Le Duc Thien, Ho Minh Trung, Nguyen Manh Hieu, Nguyen Thi Phuong, Tran Van Cong, Le Thi Ha Trang

CS gas, Dermal irritation, GHS 2025, In vivo testing.

This study employs in vivo testing on rabbit skin to evaluate the toxicity and detoxification efficacy of CS gas (o-chlorobenzylidene malononitrile) based on the GHS 2025 standards (Globally Harmonized System of Classification and Labelling of Chemicals, Eleventh revised edition). Test samples were applied via direct dermal permeation to monitor the progression of erythema and edema at fixed intervals of 24, 48, and 72 hours. The research combines experimental tear gas irritation models with simple irritation tests to accurately determine safety profiles and injury recovery capabilities. Results were determined through a standardized scoring system, allowing for the classification of chemical hazard levels according to international categories. The test samples demonstrated significant effectiveness in reducing acute irritation symptoms caused by CS gas in rabbit skin models. By monitoring erythema and edema indices, the irritation-reducing active ingredients significantly shortened epithelial recovery time compared to the control group. Observations at 24, 48, and 72 hours evidenced the ability to soothe the skin, prevent widespread inflammation, and limit deep lesions such as hyperkeratosis or alopecia. Comparison with GHS 2025 scales confirmed that these test samples could lower irritation levels from Category 2 to Category 3 or to a non-irritating status. This provides an important scientific basis for confirming the practical application of these compounds in the safe and effective treatment of lachrymatory agents. The research offers high practical value by establishing a scientific and objective evaluation process for irritation reduction in animal models. Strict application of the latest international standards from GHS 2025 not only ensures accuracy in irritation classification but also enhances the legal validity and reliability of testing results in Vietnam. The efficacy of the test samples was clearly proven through the rapid reduction of inflammatory reactions, erythema, and edema, opening great prospects for developing specialized medical support products. This serves as an important prerequisite for practical applications aimed at protecting human health against potent irritants.

Received: 05 Mar 2026, Received in revised form: 08 Apr 2026, Accepted: 11 Apr 2026, Available online: 14 Apr 2026

10.22161/ijaers.134.7