Stink-off: Quantifying and comparing foul odors

This article attempts to quantify the human smell, and compare it to the smells of other smelly creatures -- namely stink bugs and skunks. A selection from this piece appears on page 238 of The Cactus Eaters, but some of you asked to see the article in full.

WHO SMELLS THE WORST? A skunk, a stinkbug, or a Pacific Crest Trail Through Hiker

SKUNK (yes, I drew this field sketch. What can I say? Skunks are hard to draw.)





MEPHITIS MEPHITIS

POTENCY Noxious spray can render dogs temporarily blind

There's a compelling reason why Pepé Le Pew is condemned to a life of celibacy. The chemicals in a skunk's spray are so potent that one of them-3-methyl-1-butane-thiol-is on the EPA's hazardous substances list. A natural-born sharpshooter, the skunk can nail predators-or you-from an anal gland with surprising accuracy from 10 feet away. Similar to tear gas, skunk spray is one of the most effective defense systems in the animal kingdom; only the great horned owl is savage enough to prey on the stinky polecat once it unleashes its pungent potion. Bobcats, coyotes, and pumas hunt this nocturnal animal only if other prey is scarce. Even in death, the skunk's vile, sewerlike odor doesn't let up. Its gas sac often leaks fumes postmortem, creating-for the unwitting taxidermist-the mother of all occupational hazards.

STINK BUG

PENTATOMIDAE FAMILY

POTENCY Bitter ooze can leave humans nauseous




This diminutive insect recently made the Discovery Channel's short list of the foulest-smelling animals on the planet, beating out such also-rans as the beaver. Like the skunk, this shield-shaped insect defends itself by excreting a noxious liquid from slits under its body that repels snakes, birds, and other insects. If a predator somehow gets past the sharp, acidic smell and eats a stink bug, it immediately spits it out because the nasty liquid tastes as foul as it smells. If a spider finds a stink bug in its web, it will cut it free instead of eating it. No wonder. Chemically speaking, the stink bug's spew contains tridecane, a compound found in gases and some cigarettes. What's worse, the stink bug is everywhere-more than 300 species are found in the front and backcountry across the United States .

TYPICAL SMELLY THRU-HIKER

PACIFIC CREST TRAIL











POTENCY Ripe odor can clear a coffee shop

He climbs in the front seat beside you. Politeness stops you from turning away and pinching your nose. Yet you momentarily consider using that tree-shaped air freshener as a gas mask. What possessed you to give this thru-hiker a ride? After 3 weeks in the chaparral foothills of California , he now smells like the rhino enclosure at the San Diego Zoo. His suffocating reek comes not from sweat itself but from the bacteria that feed on the amino acids, fats, and oils found in human perspiration. The bacteria emit a putrid blend of chemical compounds including ammonia and methylbutanoic acid that cling to the clothes and body-and multiply with each passing day. Opening the car windows will only help so much, but at least it spreads the misery. Depending on wind conditions, someone could pick up this hiker's aroma from 100 feet away.

THE VERDICT

A shower and a load of laundry will quickly freshen up the thru-hiker. And a stink bug's nasty odor lasts a mere 60 seconds-nothing compared to the multiple days a skunk's stench could cling to your clothes if you don't wash them with bleach (the surest cure we've found). Smelliest goes to the skunk.