A lot of animals have an unpleasant odor. It often plays a role in discouraging predators from thinking they've cornered a tasty meal. But skunks seem to have perfected the art of odor-as-defense, blasting adversaries with a smell so pungent it can cause the eyes to water, or temporary blindness and even vomiting. What's the skunk's secret?
Smithsonian explains, "Skunk spray is a thiol, an organic compound with sulfur as a principal component. Sulfur has that classic rotten egg smell, and it’s what gives thiol its gag-inducing power. For detection purposes, thiols are added to otherwise smell-free natural gas, so that it will have a noticeable odor. In the case of skunk spray, the thiol is so potent that it can be smelled a half-mile away."
N-butyl mercaptan, as the spray is formally known, isn't just bad on its own. It also has a chemical reaction with water that makes the smell even worse. That's why a dog that's been sprayed by a skunk, even if she is thoroughly treated to diffuse the smell, will have a skunky odor every time she gets wet, even months after the incident.
And as for treating a sprayed pet, many people think a bath of tomato juice is the solution. But that's really just a long-standing notion that doesn't have much effect.
io9 provides an answer for getting rid of the skunk smell: "What you need is a chemical that will change the composition of the thiol group. Fortunately, baking soda and hydrogen peroxide are cheap, mild, and will do the job. They are oxidizing agents, meaning they will attach oxygen atoms to the sulfur atom in the thiol pairing, and take away its ability to stink."