3,4,5,6-Tetrabromo-o-cresol is primarily used as an antimicrobial agent and preservative in various products due to its strong bactericidal and fungicidal properties. It is commonly employed in cosmetics and skincare formulations to control the growth of acne-causing bacteria and prevent microbial contamination. Additionally, it is utilized in industrial applications such as paints, wood treatments, plastics, and textiles to protect against mold, fungi, bacteria, and odors, thereby extending the service life of materials and preventing degradation.