Why does skunk spray have such a strong and long-lasting smell?

The potent and persistent odor of skunk spray is primarily due to its chemical composition, which includes sulfur compounds known as thiols and thioacetates.12

Thiols are organic compounds structurally similar to alcohols but containing a sulfur atom in place of oxygen; they are well-known for their characteristically foul and powerful smells. Specifically, striped skunks utilize a liquid spray containing 3-methyl-1-butanethiol to deter predators. These compounds are highly offensive to humans and other animals, and their chemical nature ensures the odor remains strong and long-lasting.31

Because this spray serves as a critical defense mechanism, skunks use it with precision, aiming the liquid from specialized anal glands. They typically engage in warning behaviors—such as stamping their paws or performing a handstand—before resorting to spraying, as the glands require approximately 10 days to replenish once emptied.12