The 6 Dirtiest Places in Airplanes and Airports


It seems almost inevitable that when you fly on an airplane, you get sick shortly thereafter. Most blame the germs circulating in the air, but the cause might actually be the surfaces you're touching. To find out how dirty planes and airports are, Travelmath, an online trip calculator, performed an informal study, sending a microbiologist to swab areas at five airports and on four flights performed by two major carriers.

The scientist collected 26 samples, which were stored in sterile broth and sent to a lab to determine just how many illness-causing bacteria were present per square inch, measured in colony-forming units (CFUs). As Mashable reports, “Tests were performed on different items at each airport and on each plane, and then ranked by the median of the results."

According to Travelmath, the results showed that the surfaces in planes and airports are dirtier than some surfaces and objects in your home—and the dirtiest place of all is the tray table:

1. Tray table: 2155 CFU/sq. in.
2. Drinking fountain buttons: 1240 CFU/sq. in. (airport)
3. Overhead air vent: 285 CFU/sq. in.
4. Lavatory flush button: 265 CFU/sq. in.
5. Seatbelt buckle: 230 CFU/sq. in.
6. Bathroom stall locks: 70 CFU/sq. in. (airport)

Surprisingly, bathrooms were actually cleaner than many other places, probably because they’re regularly swabbed down. This might also be why no samples tested positive for E. Coli, a fecal coliform.

It's important to keep in mind that, though the results are interesting, this isn't a peer-reviewed study appearing in a scientific journal. It's not clear exactly what bacteria Travelmath was testing for, and, as Mashable points out, "the presence of bacteria does not necessarily mean that those exposed to it will get sick." Still, it can't hurt to take the commonsense approach to traveling that Travelmath recommends: Throw out any food that touches the tray, and make sure to carry hand sanitizer.

Here's a handy infographic that breaks all of Travelmath's findings down:

[h/t Mashable]

The Surprising Reason Why Pen Caps Have Tiny Holes at the Top

If you’re an avid pen chewer, or even just a diehard fan of writing by hand, you’re probably well acquainted with the small hole that tops off most ballpoint pen caps, particularly those classic Bic Cristal pens. The reason it’s there has nothing to do with pen function, it turns out. As Science Alert recently reported, it’s actually designed to counter human carelessness.

Though it’s arguably unwise—not to mention unhygienic—to chomp or suck on a plastic pen cap all day, plenty of people do it, especially kids. And inevitably, that means some people end up swallowing their pen caps. Companies like Bic know this well—so they make pen caps that won’t impede breathing if they’re accidentally swallowed.

This isn’t only a Bic requirement, though the company’s Cristal pens do have particularly obvious holes. The International Organization for Standardization, a federation that sets industrial standards for 161 countries, requires it. ISO 11540 specifies that if pens must have caps, they should be designed to reduce the risk of asphyxiation if they’re swallowed.

It applies to writing instruments “which in normal or foreseeable circumstances are likely to be used by children up to the age of 14 years.” Fancy fountain pens and other writing instruments that are clearly designed for adult use don’t need to have holes in them, nor do caps that are large enough that you can’t swallow them. Any pen that could conceivably make its way into the hands of a child needs to have an air hole in the cap that provides a minimum flow of 8 liters (about 2 gallons) of air per minute, according to the standard [PDF].

Pen cap inhalation is a real danger, albeit a rare one, especially for primary school kids. A 2012 study [PDF] reported that pen caps account for somewhere between 3 and 8 percent of “foreign body aspiration,” the official term for inhaling something you’re not supposed to. Another study found that of 1280 kids (ages 6 to 14) treated between 1997 and 2007 for foreign body inhalation in Beijing, 34 had inhaled pen caps.

But the standards help keep kids alive. In that Beijing study, none of the 34 kids died, and the caps were successfully removed by doctors. That wasn’t always the case. In the UK, nine children asphyxiated due to swallowing pen caps between 1970 and 1984. After the UK adopted the international standard for air holes in pen caps, the number of deaths dropped precipitously [PDF]. Unfortunately, it’s not foolproof; in 2007, a 13-year-old in the UK died after accidentally swallowing his pen cap.

Even if you can still breathe through that little air hole, getting a smooth plastic pen cap out of your throat is no easy task for doctors. The graspers they normally use to take foreign bodies out of airways don’t always work, as that 2012 case report found, and hospitals sometimes have to employ different tools to get the stubbornly slippery caps out (in that study, they used a catheter that could work through the hole in the cap, then inflated a small balloon at the end of the catheter to pull the cap out). The procedure doesn’t exactly sound pleasant. So maybe resist the urge to put your pen cap in your mouth.

[h/t Science Alert]

Carnivorous Hammerhead Flatworms Are Invading France

It’s no hammerhead shark, but the hammerhead flatworm has become a real menace in France. Or at least a menace to earthworms, as Earther reports.

Believed to be an invasive species from Asia, the hammerhead flatworm was only recently recorded in France, as is documented in a new study (titled "Giant worms chez moi!") published in the journal PeerJ. However, based on reports, photographs, and videos sent in by citizens across the country, scientists determined the pests have gone undetected for nearly 20 years. This came as a shock, especially because the worms can measure more than a foot in length.

In recent years, three species of the carnivorous worm have quietly taken over French gardens and have even been spotted in metropolitan areas. Some species immobolize their prey with tetrodotoxin, the same powerful neurotoxin that makes pufferfish so poisonous. The worms secrete digestive enzymes, allowing them to dissolve earthworms and slugs their size.

Jean-Lou Justine, co-author of the study, says their eating habits are a concern. "Earthworms are a major component of the soil biomass and a very important element in the ecology of soils," Justine tells Earther. "Any predator which can diminish the populations of earthworms is thus a threat to soil ecology."

Archie Murchie, an entomologist who was not involved in the study, told The Washington Post that the worms will continue to spread in step with global trade. The worms were also seen in overseas French territories, including one worm with a blue-green hue that is probably a newly detected species, Murchie tells the newspaper.

[h/t Earther]


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