PCBs, or polychlorinated biphenyls, are a group of synthetic chemicals that were widely used in industrial applications, such as electrical equipment, hydraulic fluids, and plasticizers. They are known for their chemical stability and resistance to heat, which made them popular in various manufacturing processes. However, their use was banned in many countries due to environmental and health concerns. PCBs can accumulate in the environment and in living organisms, leading to potential health risks, including cancer and immune system issues. They can enter the food chain through contaminated soil and water, affecting wildlife and humans alike. Cleanup and management of PCB contamination remain significant challenges for environmental protection efforts.