What with one thing and another, I’ve spent a lot of time in public restrooms. And, having been a scientist in my previous professional incarnation, I can’t help observing things, and drawing statistical inferences. Which is why I am in a position to inform you that roughly half the female population of the US suffer from the twin delusions that 1) butt-cooties exist, and 2) they will, given half a chance, leap several inches from a toilet seat and burrow into the skin of an unsuspecting buttock, resulting in scrofula, assorted STD’s, herpes, and probably leprosy.

I draw these conclusions from the fact that roughly half the time I enter a public restroom cubicle, I observe that the previous user has peed on the seat. Ladies…

I can only guess that at some point in an impressionable youth, these women were told by some female authority figure that One Must Never SIT On A Public Toilet, “because you might catch something.” Firmly indoctrinated with this policy, they do not sit on public toilets. They hover. Ladies, ladies…

Look. The skin of the buttocks is actually pretty germ-free, owing to the fact that we normally keep them covered and don’t (usually) touch other people, animals, etc. with them. Your butt is much cleaner—microbially-speaking—than are your hands.

Various studies of the bacterial content of public restrooms indicate that there are a LOT more germs on the door of said restroom than there are on any toilet seat therein. You acquire millions more microbes by shaking hands with someone than you would if our social system involved mutual butt-rubbing. (To say nothing of the teeming worlds of microorganisms you acquire every time you accept change from the counter-guy at Burger King. How many of you race to the bathroom and scrub your hands after ordering the meal, but before eating it?)

In order actually to catch one of the communicable diseases with which excrement or other bodily fluids are associated, two things would have to occur: 1) the bodily fluid of an infected person would have to be applied to the toilet seat (which would not happen, if said person would sit her bottom on the potty where it belongs and not spray the thing like a hippopotamus), and 2) an uninfected person’s mucous membranes must come in contact with said fluids, within the few seconds that most bacteria and virii can survive outside the human body. You don’t have mucous membranes on your buttocks.

Now, by and large, urine really doesn’t contain all that many bacteria (Male urine contains almost none, owing to the fact that its exit is, um, less impeded by surrounding tissue. A good many alchemical and medical recipes up through the early 19^th century require “urine of a newborn male child” as an ingredient—this being the most sterile water available). Feces…well, yes. And I have in fact encountered the Really Nasty evidence that there are not only seat-pee-ers, but also seat-poopers (to say nothing of the occasional person who is so afraid of physically encountering a public toilet that they actually don’t hit it at all, and leave the evidence of their mental derangement on the floor of the facility), but this is fortunately rare.

All right. In periods of heavy traffic, one might possibly encounter a live bacterium or virus present in the urine that some inconsiderate idiot has left on a toilet seat. Not likely, but faintly possible. Are you going to encounter it with your mucous membranes? Not unless your excretory habits are both Highly Athletic and Dang Unusual.

OK. So if the risk of catching a bacterial or viral disease by sitting on a dry toilet seat is negligible, then plainly, the Thing to Fear must be…Butt-cooties!

Traveling as much as I do, I am in a position to collect international data, albeit in an anecdotal and unstandardized manner. On the basis of such casual observation, though, I hypothesize that while butt-cooties presently have a fairly wide global distribution, they probably originated in the United States. Speaking generally, at least fifty percent of all public toilets in US airports, convenience stores, museums, and restaurants indicate evidence of infestation (judging from the aversive techniques employed by the patrons). European toilets have a much lower incidence—perhaps 10-15%.

(Point of etiquette: ought one to meet the eyes of, and/or nod to, a person emerging from a toilet cubicle that one proposes to enter? Common politeness would argue for such cordial acknowledgement—but if the next few seconds reveal that the departing patron was possessed of butt-cooties, this might lead one to think harsh and unchristian thoughts of said person, and surely it’s worse to think unchristian thoughts (WWJD? I’m pretty sure He wouldn’t pee on a public toilet seat, and if He did, He would certainly wipe it off. Ditto the Buddha, and doubtless any other religious figure you care to name) about someone whose face is imprinted in your short-term memory, than of an unknown quantity.)

In fact, we might hypothesize the geographical origin of butt-cooties as having occurred in or near Chicago. On what basis? Well, of all the airports I’ve been in (and I’ve been in a lot of airports, from New Zealand to Saskatchewan), only O’Hare International has public toilets equipped with a sliding cylinder of plastic sheeting that encases the seats; you wave your hand in front of a magic button, and voila! The plastic slides round the seat, and you are presented with a pristine surface on which to park your booty. Such is the prevailing fear of butt-cooties, though, that people pee on these toilet seats, too.

Well, there’s no arguing with psychological aberration, and thus I make no attempt to persuade Those Who See Butt-Cooties away from their convictions. I would, though, urge them—in the most kindly manner—to address the results of their antisocial psychosis, and thus leave them with this classic advice:

“If you sprinkle when you tinkle—

Please be neat, and wipe the seat.”