Used primarily as a reference standard in environmental testing laboratories to detect and quantify polychlorinated biphenyl (PCB) contamination in soil, water, and biological samples. Its well-defined structure allows for accurate calibration of analytical instruments such as gas chromatographs and mass spectrometers. Due to its persistence and toxicity profile, it also serves in research studying the fate, transport, and degradation of chlorinated organic pollutants in ecosystems. Additionally, it is employed in toxicological studies to assess the health impacts of long-term exposure to PCBs, particularly regarding endocrine disruption and bioaccumulation in food chains.