I feel sorry for the airlines, who are flying through turbulent skies these days with the skyrocketing fuel costs. To cut their soaring bills for jet fuel, they’re trying to reach their perfect weight—quickly. American and Southwest say they’re washing their planes more often to reduce the drag caused by dirt and debris. Delta pilots may have just one pilot bring the heavy pilot manuals into the cockpit, which would save 15 pounds. American is replacing bulky drink carts with ones that weight 17 pounds less, and Delta is swapping heavier seats for models weighing five pounds less.

Since water weighs 8.3 pounds per gallon—more than a gallon of jet fuel at 6.8 pounds—bathroom faucets and toilets are being filled with less water. The bathrooms on airplanes have always been problematic, at least for me, because they are flying germ farms. San Diego State biology professor Scott Kelley took a small but scientific sampling of airline cleanliness several years ago when participants swabbed surfaces at ten different places aboard various flights. They took biological evidence not only from armrests and tray tables, but toilet seats and handles, sinks, floors, unused paper towels, and doorknobs coming in and out of the planes’ bathrooms.

The good professor said the results were what you’d expect from a fraternity house. He discovered opportunistic pathogens like Streptococcus, Staphylococcus, Cornybacterium, Proprionibacterium, and Kocuria. Kelley said the situation doesn’t warrant wearing surgical gloves the next time you board a flight, but he mentioned that whenever he flies and uses the facilities, he washes his hands well and uses a paper towel to open the lavatory door as he leaves.

I’ve opened more lavatory doors with a paper towel than I care to count, and you should, too. The bathroom knob was the nastiest part of the plane, Scott Kelley said.