Used primarily as a dielectric fluid in electrical equipment such as transformers and capacitors due to its high thermal stability and insulating properties. Also found application in hydraulic systems, heat transfer systems, and as a plasticizer in paints and coatings. Its use has been largely discontinued due to environmental persistence and toxicity concerns, leading to widespread regulation and remediation efforts. Commonly encountered in environmental testing and analysis to monitor contamination in soil, water, and biological samples.