Packing for Mars: The Curious Science of Life in the Void

by Mary Roach

  Soviet space biologist V. N. Chernigovsky, in 1969, carried out a restricted-bathing experiment of his own, this one including bacteria colony counts. The bacteria populations in subjects’ armpits and groins plateaued somewhere between the second and third weeks. At which point there were roughly three times as many colonies as on freshly washed skin. (Except on the feet* and buttocks, where there were seven to twelve times as many.) A Navy study turned up similar findings; here some subjects’ bacteria counts even began to drop after two weeks.

  The other explanation for the odor plateau is that the men’s body odor had become so strong that it was impossible for whoever was judging it to detect incremental changes. Weber’s Law provides the explanation. The detection threshold for changes in a particular smell (or sound or sensation) varies according to the intensity of the background smell (or sound or sensation). Say you are in a noisy restaurant. If the noise level rises a few decibels, you can’t tell. Had the room been quiet, you could easily tell. If someone’s armpits have been shouting for a few days, it’s hard to tell when they’re shouting a little louder. Jim Leyden gives the example of his son, who was a rower in college. One year the team decided they were going to wear the same rowing outfits until they lost. “Well, they became national champions that year. You could not get near that boat. The smell may have plateaued, but as far as I was concerned, it was just constantly horrible.”

  Eventually the mind stops registering the body’s smell. In Leyden’s words, “It’s going, ‘I don’t need to bother telling you this anymore.’” Unfortunately for a group of AMRL subjects in a twenty-day no-bathing Apollo simulation, this point didn’t arrive until day eight.

  NASA would have done well to add body odor anosmia to its list of desired astronaut traits. Some people* are genetically unable to smell (i.e., they’re anosmic to) one or both of the two BO heavies: 3-methyl-2-hexanoic acid and androstenone. “Have you ever been on an elevator with someone and wondered, ‘How can he come on here smelling like that?’ Well, he may be anosmic to his odor,” Leyden says. “And those of you who have never experienced that, you may be one of those people on the elevator that everyone’s wondering about.”

  Aside from body odor, the most common contributor to what one researcher called “perceptions of personal dirtiness” is not dirt per se, but bodily emanations that have built up on the skin: grease, sweat, and scurf,† to be specific. Where you have hair, you have sebaceous glands; that is to say, everywhere but your palms and the soles of your feet, where greasiness is a slip, trip, and fall hazard and thus a survival liability.

  The 1969 Soviet restricted-hygiene experiments monitored the build-up of oils, or sebum, in male volunteers. (Here, in addition to not bathing, the subjects had to spend “most of their time sitting in an armchair.” The simulated astronaut of the sixties was a stinky guy watching TV in a dirty undershirt.) For the first week without bathing, the skin’s oiliness remained constant. Why didn’t it increase? Because clothes are surprisingly effective absorbers of sebum and sweat. The Soviet researchers collected wash water from the subjects’ skin in one basin, and wash water from their clothes in another. They compared the amounts of grease, sweat, and dander in the two tubs. Eighty-six to 93 percent of the skin’s emanations were in the water where the clothing had been. In other words, all but 7 to 14 percent of the men’s filth had been absorbed by the fabric of their clothing. This was true of cotton, cotton-rayon blend, and, to a lesser extent, wool.

  The Soviet findings help explain the lackadaisical hygiene practices of the sixteenth and seventeenth centuries. Renaissance doctors discouraged washing with water. Removing the protective layer of oil from the skin, they believed, left the bather vulnerable to plagues, tuberculosis, and a host of other ills then believed to spread via “miasmas” that seeped into the body through the pores. Queen Elizabeth I, her era’s version of a clean freak, famously wrote, “I bathe once a month, whether I need it or not.” Many let it go a year.

  But here’s the thing: Instead of showering once or twice a day, Renaissance men and women would change their undersmocks and chemises. The men of Gemini VII and the AMRL chamber, on the other hand, couldn’t change their underthings. The authors of the AMRL chamber study noted that the subjects’ clothes eventually began “sticking to the…groin and other body fold areas and were very odorous and starting to decompose,” a condition described as “very troublesome.” Lovell told me the Gemini VII long johns were in bad shape by the end of the mission. “They were,” he allowed, “pretty smudged around the crotch area”—even more so than those of the average person who didn’t bathe or change his underwear for two weeks, because the average person wasn’t testing a new NASA urine management system that “leaked considerably sometimes.” For instance, on the second day of the flight, when Lovell, reporting to Mission Control that he was ejecting urine from the spacecraft, noted, “Not too much of it; most of it’s in my underwear.”

  At a certain point, clothes reach their saturation point, and sebum begins to accumulate on the skin. According to the Soviet researchers, who monitored oil levels on subjects’ chests and backs, it takes five to seven days for a cotton garment to reach this point. It is difficult to pinpoint the day when the Gemini VII astronauts began to notice the buildup on their skin. By day ten, they were “starting to itch” and “getting a little crummy” in the scalp and crotch. Here they are on day twelve:

  MISSION CONTROL: Gemini VII, this is Surgeon. Frank, do you have any lotion remaining?

  BORMAN: Any lotion?

  MISSION CONTROL: Roger.

  BORMAN: We have some but we sure don’t need it, Jack. We are as greasy as can be.

  It is unusual to come across the word lotion in a NASA mission transcript. Borman seemed nettled by NASA’s preoccupation with skin care, as though it were compromising the overall manliness of the mission. At one point, the flight surgeon comes on the microphone to ask, “And how are your skins?” Earlier, he’d accosted Borman out of the blue with the inquiry, “Are you having any difficulty with drying of your lips?” “Say again please?” answers Borman. You get the sense he heard him fine. On the fourth day, Mission Control fixated on how much Borman was perspiring. Borman, like his epidermis, had reached the saturation point. He refused to answer, forcing Mission Control to try to enlist Lovell’s help.

  MISSION CONTROL: Do you notice in looking at him that his skin is moist?

  LOVELL: I’ll let him answer that.

  BORMAN: [silence]

  MISSION CONTROL: Have you been sweating at all, Frank?

  BORMAN: [silence]

  MISSION CONTROL: Gemini VII, this is Carnarvon. Did you copy?

  BORMAN: About sweating? I’d say, yes, I’m perspiring a little.

  MISSION CONTROL: Very well. Thank you.

  Once a set of clothes becomes saturated and oil starts to build up on the skin, what’s the end point? Does uncleansed skin grow ever greasier as the days pass? It does not. According to the Soviet research, the skin halts its production of sebum* after five to seven days of not bathing and not changing one’s increasingly well-greased clothing. Only when the person changes his shirt or takes a shower do the sebaceous glands get back to work. Skin seems happiest with a five-day buildup of oils. Listen to Professor Elaine Larson, editor of the American Journal of Infection Control, talking about the stratum corneum, the outermost layer of human skin: “This horny layer has been compared to a wall of bricks (corneocytes) and mortar (lipids)” and helps “maintain the hydration, pliability, and barrier effectiveness of the skin.”

  Do we compromise our skin’s health by constantly scrubbing off the mortar? Does our skin want us to bathe every five days? Hard to say. It’s true that especially zealous hand washers—hospital personnel and certain obsessive-compulsives—often develop irritation and eczema. Twenty-five percent of the nurses in one study, writes Larson, had dry, damaged skin. Ironically, the nurses may be exacerbating the very thing that hand-washing seeks to prevent: the sprea
d of infectious bacteria. Larson says healthy skin sheds 10 million particles a day, and 10 percent of those harbor bacteria. Dry, damaged skin flakes off more readily than healthy, lubricated skin and thus disperses more bacteria. Damaged skin also harbors more pathogens than healthy skin. As Larson says, “Perhaps sometimes clean is too clean.” Most Americans don’t wash often enough to cause skin problems, but they certainly wash more than necessary. In the words of some academic I can’t name because I’ve lost the first page of his paper, “Personal hygiene as practiced in the U.S. today is largely a cultural fetish, actively promoted by those with commercial interests.”

  In space, as in the military, bathing is more an issue of morale than of health. Space agencies, recognizing what one researcher called “the psychological inadequacy of sponge baths,” devoted a lot of time and money in the 1960s trying to develop a zero-gravity shower for space stations. One of the earliest prototypes tested was a “shower suit.” The technical report I read included the following less-than-encouraging summary: “Results leave much to be desired in the showering, rinse, and drying procedures.” The usual arrangement doesn’t work; the water sprays from the shower head for a few inches and then collects in an expanding blob: fascinating, but of little ablutionary help. If you hold the shower head close enough to forestall the big blob, then the water ricochets off your skin, forming floating drops that you then have to spend ten minutes chasing down to keep them from floating out into the station. “It turned out to be easier just to forget the whole thing,” said astronaut Alan Bean, of the collapsible Skylab shower.

  The shower on the Soviet space station Salyut used air flow to try to draw the water down toward the cosmonauts’ feet. It was minimally successful. Blobs formed, and blobs tend to cling to the body’s concavities, including the mouth and nostrils. To keep from choking, cosmonaut Valentin Lebedev and his crewmate Tolia Berezovoy wore snorkeling gear. “What an exotic sight it was,” wrote Lebedev in his diary. “A naked man [flying] across the station,…with snorkel in his mouth, goggles over his eyes, a clip on his nose.” Understandably, the crew of Salyut 7, like Elizabeth I, showered just once a month. These days there are no space showers. Astronauts wipe themselves with moistened towels and rinseless shampoo.

  Bathing is more important on the space stations, because the missions are longer and they include daily exercise regimens that ratchet up the sweat level. As an adjunct to body wiping, Japanese astronauts on the ISS have been wearing “J-Wear,” developed at Women’s University in Tokyo out of fabric “with the function of dissolving foulness and body odor by photocatalyst and prevention of the rotten smell of sweat by the antibacterial nano-matrix finishing technique.” Astronaut Wakata Koichi (pronounced, perhaps aptly, co-itchy) wore the same J-Wear underpants for twenty-eight days without complaint.

  The astronauts of Gemini VII could only dream of “comfortable everyday clothes for life in a spaceship,” as one press release calls J-Wear. They wore hot, heavy, bulky spacesuits for pajamas. The subjects in the Air Force Gemini VII simulation were plagued by “chafing and much irritation in groin.” In case you have ever questioned the value of thorough wiping and regular changes of underwear, here’s a reason. In people with poor bathroom habits or 1960s Air Force hygiene restrictions, fecal bacteria migrate. Wright-Patterson researchers sampled thirteen sites on the men’s bodies to check for E. coli. It was a remarkable Diaspora. Fecal bacteria had made its way to the men’s eyes, ears, and, in two cases, toes. Five out of six of the Soviet subjects who sat in armchairs for thirty days developed folliculitis—bacterial infection in the hair follicles on the skin. Three developed boils—especially bad, swollen, painful, infected follicles. (The Soviet paper uses the old-timey term “furuncle.” You almost want one just to be able to go around saying “furuncle.”)

  Lovell doesn’t recall any skin problems. “The difference is zero G,” he told me. “That’s the key to the whole deal.” When a man floats a few inches above his chair, when his arms hover out away from his sides, he has less of the chafing and irritation normally caused by damp, filthy clothes rubbing sweaty, unwashed skin. The astronauts’ underwear didn’t get plastered to their buttocks. Whatever bacteria lurked in their sweat, it wasn’t getting ground into their follicles. There is a condition called hot-tub folliculitis, which often appears on hot tubbers’ buttocks and the backs of their thighs—just where the friction and pressure is. (The water in a hot tub is hot, but not hot enough to kill bacteria. An undertreated hot tub is essentially, quoting University of Arizona microbiologist Chuck Gerba, “E. coli soup.”)

  DAY SIX OF GEMINI VII. Frank Borman is on the mic. The exchange is proceeding in the macho, jargony manner of pilot-to-ground communications. Until:

  MISSION CONTROL: Stand by for the Surgeon, Gemini VII.

  BORMAN: [silence]

  MISSION CONTROL: Gemini VII, this is Surgeon. Have you had any dandruff problem up there, Frank?

  BORMAN: No.

  MISSION CONTROL: Say again.

  BORMAN: N. O. No, negative!

  Commander Borman did not wish to discuss skin care. But later, in his memoir, he would write about “our scalps” and about the case of “terminal dandruff” he had. Though it probably wasn’t, technically speaking, dandruff. Dandruff is caused by an inflammatory skin response to oleic acid, which the scalp fungus Malassezia globosa excretes after dining on your scalp oils. Either you’re sensitive to oleic acid or you’re not. If Borman didn’t have dandruff before he went into space, he didn’t have it afterward, says dermatologist Jim Leyden. Leyden once paid prisoners to not wash their hair for a month, specifically to see if they developed dandruff. They did not. The flakes on Borman’s head and skin were most likely the accumulation of millions of shed skin particles—particles normally washed away in the shower—mixing with sebum and clumping together.

  The atmosphere in Antarctic field camps is similarly dry and shower facilities similarly nonexistent or cumbersome, making the six-week Antarctic Search for Meteorites field season a good analog for space hygiene. “Six weeks of dead skin is like two whole layers,” says team leader Ralph Harvey. Sometimes it all comes off at once, in the first wash. Harvey admits to being fascinated by the spectacle. “I remember coming back and taking a shower and the whole end cap of my finger would just come off.”

  What makes the dander situation bearable in Antarctica is that you can step outside your domicile and shake out your long johns and sleeping bag. You can’t do this in space or simulated space. The description of the Navy space cabin simulator at the end of the experiment was like a ski report. “A fine layer of powdery scales was found to cover the floor of the chamber.”

  In zero gravity, the flakes never fall. I asked Lovell about this. I believe my exact words were, “Was it just like a snow globe in there?” He said he didn’t recall anything like that. Or not “of such magnitude that it would stick in my mind all these years.” (For the thing that did stick in his mind all these years, see chapter 14.)

  The head in general is a problem. The majority of our sebaceous glands are attached to hair follicles, thus the unwashed scalp quickly becomes a greasy thing. So much so that the bathphobic hordes of the sixteenth century would rub powder or bran into their scalps before retiring for the night, much as homeowners today sprinkle kitty litter on motor oil spills. Like sweat, sebum develops a distinctive aroma as bacteria break it down. “At least two of the Skylab astronauts reported that their heads developed offensive odors,” noted space psychologist Jack Stuster in a 1986 NASA report on space station habitability.

  BORMAN AND LOVELL did not stay in their suits the entire flight, as NASA had originally planned. On day two, flight surgeon Charles Berry began lobbying NASA management on their behalf. A compromise was struck: Only one man had to stay suited (in case of a depressurization emergency). Borman drew the short straw, and Lovell squirmed out of his suit. For years, Lovell recalls, his son would tell friends, “Dad orbited the Earth in his underwear!”

&nbs
p; By hour 55, Borman has his suit unzipped and halfway off. By hour 100, he petitions NASA management to let him take it all the way off. Five hours pass. Houston comes back on the line. Borman may take off his suit, but only if Lovell gets back in his. Lovell tries to resist (“I would prefer to leave it this way if you don’t mind”), but NASA stands firm. Hour 163: Lovell is in, and Borman is out. Eventually, Berry prevails, and both suits come off. Otherwise, Berry recalls in his oral history, “I don’t think we would have completed fourteen days in that spacecraft…. You’ve got two guys in spacesuits and they’re sitting like this, your leg over in the other guy’s lap. It’s a really difficult situation.”

  It could be worse. Try living in bed for three months.

  THE HORIZONTAL STUFF

  What If You Never Got Out of Bed?

  Leon M. doesn’t appear to have the “right stuff.” He has a messy past and lingering debts. His most recent job was as a security guard. These days, Leon spends entire weeks in bed, watching movies and playing video games. Beneath the sweatpants and tattoos, however, there’s an astronaut of sorts. Leon’s skeleton has been diminishing at about the same rate as an astronaut’s in space.