Para-dichlorobenzene (PDCB) is a colorless, crystalline compound with a strong odor. It is a type of dichlorobenzene, which consists of a benzene ring with two chlorine atoms attached at opposite positions. PDCB is commonly used as a moth repellent and in air fresheners, as well as in some industrial applications. This chemical is produced through the chlorination of benzene and is known for its ability to sublimate, meaning it can transition from solid to gas without becoming liquid. While effective for pest control, exposure to PDCB can pose health risks, including respiratory issues and skin irritation.