PeCB

PeCB, short for pentachlorobenzene, is a chlorinated aromatic hydrocarbon with the formula C6HCl5. It consists of a benzene ring bearing five chlorine substituents and belongs to the wider family of chlorobenzenes. PeCB is mainly produced as a byproduct in chlorination processes and during combustion of chlorinated organics; it has also been used in the past as an intermediate in chemical synthesis, though such uses are now limited or prohibited in many jurisdictions due to health and environmental concerns. It is a relatively persistent, lipophilic compound with low water solubility and low volatility, which leads it to accumulate in soils, sediments, and fatty tissues of organisms.

In the environment, PeCB is persistent and can be transported via air and water, leading to widespread distribution with detections in air, soil, sediment, and biota. It tends to sorb to organic matter and bioaccumulate, raising concerns for wildlife and humans exposed through diet and environmental media. Toxicological data are limited but indicate potential hepatotoxic, immunotoxic, and developmental effects in laboratory animals at sufficiently high exposures; human data are less clear, and risk assessments emphasize long-term exposure and bioaccumulation.

Regulatory and monitoring frameworks typically classify PeCB as a persistent organic pollutant and regulate its production, use, and release in many countries and international agreements. Analytical detection is commonly achieved by gas chromatography coupled with mass spectrometry or electron capture detection in environmental and biological samples. Ongoing surveillance aims to track environmental levels, identify sources, and minimize human and ecological exposure.