Phosgene is a colorless gas with a musty odor, primarily used in the production of chemicals, particularly in the manufacture of isocyanates and polycarbonate plastics. It is highly toxic and can cause severe respiratory damage if inhaled, making it a dangerous substance in industrial settings. Discovered in the 19th century, phosgene was also used as a chemical weapon during World War I. Due to its hazardous nature, strict safety regulations are in place for its handling and storage, ensuring that workers are protected from its harmful effects.