Used primarily in industrial settings as a flame retardant and insulator in electrical equipment due to its chemical stability and resistance to heat. It has been applied in the manufacturing of capacitors, transformers, and other electrical components to enhance safety and performance. However, its use has significantly declined due to environmental and health concerns, as it is a persistent organic pollutant. In research, it serves as a reference compound for studying the environmental impact and toxicology of polychlorinated biphenyls (PCBs).