Used as a reference standard in environmental testing to identify and quantify polychlorinated biphenyl (PCB) contamination in soil, water, and air samples. Commonly employed in gas chromatography-mass spectrometry (GC-MS) and high-resolution analytical methods to ensure accurate detection of PCB congeners. Essential for monitoring industrial emissions, assessing hazardous waste sites, and verifying compliance with environmental regulations. Also used in research studies focused on persistent organic pollutants and their impact on ecosystems and human health.