How Much Pee in a Pool is Too Much Pee?


Last week, a study by Chinese and American scientists revealed another reason to not pee in pools, which had more to do with chemistry than good manners. 

The researchers found that when urine and chlorine meet in the right quantities, they can create two byproducts, trichloramine and cyanogen chloride. The latter can be harmful to the lungs, heart, and nervous system. It’s nothing to get your bathing suit in a bunch over, though. Even with chlorine levels far beyond what’s used in the average swimming pool, the amounts of these chemicals produced in the study were still in the World Health Organization’s “safe” range. In other words, you’re probably not going to hurt yourself emptying your bladder during a swim. That said, the study still warned that the chemical could “adversely affect air and water quality” in and around the pool. Plus, it’s just gross. 

At Ars Technica, the research made editor Casey Johnston wonder just how much pee in a pool it would take to make a harmful amount of those chemicals. And after some number crunching, Johnston found that creating a death pool of pee is a pretty tall order.

To get enough chlorine and uric acid together to create a toxic level of cyanogen chloride in an Olympic-sized swimming pool, Johnston says you’d need three million people emptying an entire day’s worth of highly concentrated urine into water that’s more chlorinated than normal. 

“If you could get at that pool without dying of either suffocation or drowning in other people’s urine,” she writes, “you could probably pull off death by cyanogen chloride poisoning or at least a pretty good coma.”

Even in this pretty unrealistic situation, there’s a snag. Even at high concentrations, the researchers who did the study found that a lot of their chlorine was consumed by the uric acid. So really, you’d need an even higher chlorine concentration—a whopping half a liter of chlorine per liter of water—to create enough cyanogen chloride.

“In the end we need a pool that is two parts water to one part chlorine and would probably burn the eyeballs out of your sockets and make your skin peel away from your bones,” says Johnston. Get three million people to pee into that, without crushing each other or melting away like Nazis opening the Ark of the Covenant, and you’ve got enough cyanogen chloride to kill (also, the world’s worst pool party).

You can read Johnston’s whole thought experiment here

Why Are Mugshots Made Public Before a Suspect is Convicted by the Court?

Jennifer Ellis:

Several reasons.

1. Mugshots can help find people when they have absconded, or warn people when someone is out and dangerous. So there is a good reason to share some mugshots.

2. Our legal system requires openness as per the federal constitution, and I imagine most if not all state constitutions. As such, this sort of information is not considered private and can be shared. Any effort to keep mugshots private would result in lawsuits by the press and lay people. This would be under the First and Sixth Amendments as well as the various Freedom of Information Acts. However, in 2016 a federal court ruled [PDF] that federal mugshots are no longer routinely available under the federal FOIA.

This is partially in recognition of the damage that mugshots can do online. In its opinion, the court noted that “[a] disclosed booking photo casts a long, damaging shadow over the depicted individual.” The court specifically mentions websites that put mugshots online, in its analysis. “In fact, mugshot websites collect and display booking photos from decades-old arrests: BustedMugshots and JustMugshots, to name a couple.” Some states have passed or are looking to pass laws to prevent release of mugshots prior to conviction. New Jersey is one example.

a) As the federal court recognizes, and as we all know, the reality is that if your picture in a mugshot is out there, regardless of whether you were convicted, it can have an unfortunate impact on your life. In the old days, this wasn’t too much of a problem because it really wasn’t easy to find mugshots. Now, with companies allegedly seeking to extort people into paying to get their images off the web, it has become a serious problem. Those companies may get in trouble if it can be proved that they are working in concert, getting paid to take the picture off one site and then putting it on another. But that is rare. In most cases, the picture is just public data to which there is no right of privacy under the law.

b) The underlying purpose of publicity is to avoid the government charging people and abusing the authority to do so. It was believed that the publicity would help protect people. And it does when you have a country that likes to hide what it is up to. But, it also can cause harm in a modern society like ours, where such things end up on the web and can cause permanent damage. Unfortunately, it is a bit of a catch-22. We have the right to know issues and free speech rights smack up against privacy rights and serious damage of reputation for people who have not been convicted of a crime. The law will no doubt continue to shake out over the next few years as it struggles to catch up with the technology.

This post originally appeared on Quora. Click here to view.

What Happens When You Flush an Airplane Toilet?

For millions of people, summer means an opportunity to hop on a plane and experience new and exciting sights, cultures, and food. It also means getting packed into a giant commercial aircraft and then wondering if you can make it to your next layover without submitting to the anxiety of using the onboard bathroom.

Roughly the size of an apartment pantry, these narrow facilities barely accommodate your outstretched knees; turbulence can make expelling waste a harrowing nightmare. Once you’ve successfully managed to complete the task and flush, what happens next?

Unlike our home toilets, planes can’t rely on water tanks to create passive suction to draw waste from the bowl. In addition to the expense of hauling hundreds of gallons of water, it’s impractical to leave standing water in an environment that shakes its contents like a snow globe. Originally, planes used an electronic pump system that moved waste along with a deodorizing liquid called Anotec. That method worked, but carrying the Anotec was undesirable for the same reasons as storing water: It raised fuel costs and added weight to the aircraft that could have been allocated for passengers. (Not surprisingly, airlines prefer to transport paying customers over blobs of poop.)

Beginning in the 1980s, planes used a pneumatic vacuum to suck liquids and solids down and away from the fixture. Once you hit the flush button, a valve at the bottom of the toilet opens, allowing the vacuum to siphon the contents out. (A nonstick coating similar to Teflon reduces the odds of any residue.) It travels to a storage tank near the back of the plane at high speeds, ready for ground crews to drain it once the airplane lands. The tank is then flushed out using a disinfectant.

If you’re also curious about timing your bathroom visit to avoid people waiting in line while you void, flight attendants say the best time to go is right after the captain turns off the seat belt sign and before drink service begins.

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