Watchly Safety Review

Measuring How Much Pee Is In Your Pool

Mark Rober

10:30 · 46.0M views · August 22, 2017

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Minor FlagsReviewed June 2026

1Minor Flag

7No Issues

This video is safe for most school-age kids and is genuinely educational, using real science to answer a question kids already wonder about. The gross-out factor is the whole point, but it's handled with curiosity and humor rather than shock value, making it a surprisingly solid introduction to chemistry, measurement, and public health.

Content Breakdown · 8 Categories

Strong & Crude LanguageNot present

Realistic Violence, Threats & WeaponsNot present

No realistic violence or threats appear in this video; the sound effects at the end (bomb explosion, gun firing, glass breaking) appear to be comedic/stylized outro sound effects rather than any realistic depiction of violence.

See evidence (1)

“End-of-video sound effects: '(bomb explosion)', '(gun firing)', '(glass breaking)' — appear to be comedic sound effect montage, not realistic violence”~11:00 (end of video)

Parasocial & Emotional ManipulationNot present

Toxic Behavior ModelingNot present

No toxic behavior modeling is present; the video explicitly discourages peeing in pools ('be cool and don't pee in the pool') and frames the science as a reason to adopt better behavior.

See evidence (1)

“'So be cool and don't pee in the pool' — actively discourages the behavior being studied”~7:30

Low-Quality, Extreme & Stunt ContentNot present

Hidden Advertising & Sponsored ContentA little

No hidden or undisclosed sponsorships are present; the video references real scientists (Lindsay Blackstock, Professor Ernest Blatchley) and links to their published academic papers transparently, which constitutes legitimate citation rather than promotion.

See evidence (1)

“Links to Lindsay's Papers and Professor Blatchley's Papers in description — these are academic citations, not commercial promotions”

Sexual Education & Reproductive HealthNot present

Playful & Fantasy ViolenceNot present

The comedic sound-effect montage at the video's end (bomb, gun, glass breaking, cheering) appears to be a lighthearted stylized outro rather than any meaningful playful violence sequence, and no gameplay or fantasy combat is present.

See evidence (1)

“End-of-video sound effects montage: '(bomb explosion) (funky music) (glass breaking) (ball crashing) (group cheering and yelling) (gun firing)' — brief stylized comedic outro”~11:00

What Parents Need to Know

This Mark Rober-style science video investigates how much urine ends up in swimming pools using a clever real-world chemistry method developed by a university researcher. Kids will learn about mass spectrometry, chemical tracers, and how chlorine reacts with urine to form trichloramine — the actual source of that 'pool smell.' The subject matter is inherently potty-humor territory, but the tone stays scientific and informative throughout. There's a brief clip of someone on TV apparently drinking urine as a cultural reference, and the video ends with some sound effects (including a gunshot sound) that appear to be unrelated outro clips. The video actively encourages responsible behavior by telling viewers not to pee in the pool and explains the real health reasons why. There is no strong language, violence, or inappropriate content — just urine discussed in a clinical, educational context.

Talk to Your Kids About

1Why do you think scientists use artificial sweeteners to measure pee instead of just testing for urine directly? What does that tell us about how scientists solve tricky problems?
2The video says trichloramine — not chlorine — causes red eyes and that 'pool smell.' Did that surprise you? What else might you have assumed was true that turned out to be different?
3The video says pee is actually sterile and mostly water. Does knowing the science make you feel differently about swimming in a public pool? Why or why not?
4What do you think is the right thing to do when you need to use the bathroom while swimming, and why does it actually matter for other people's health?

Protected Viewing

What's This Video About?

Knowledge is power! Even if that knowledge causes you to rethink some of those lovely summer memories. Lindsay's Papers: https://www.dropbox.com/sh/5wvki0qeo1xl0e5/AACz2Lrn4BdTLXp7vFeYpfr2a?dl=0 Professor Blatchley's Papers: https://www.dropbox.com/sh/r8bikvavi1s1t32/AADNKIIZ_I6qlhNVG3fG-pbQa?dl=0 MUSIC- 0:11- Ceral Killa- Blue Wednesday - https://soundcloud.com/bluewednesday/ 2:53- Berlin- Andrew Applepie- http://andrewapplepie.com/ 3:40- Devil in Disguise- Danijel Zambo- https://soundcloud.com/danijel-zambo 9:01- Q- Blue Wednesday - https://soundcloud.com/bluewednesday/ 11:08- Too Happy to be cool by Notebreak- https://soundcloud.com/notebreak/dubstep-too-happy-to-be-cool Summary: I visited Lindsay Blackstock at the University of Alberta to learn about her ingenious method for measuring the amount of pee in a pool by looking at the concentration of an artificial sweetener called Acesulfame Potassium. We looked at some samples from some pools in my area to determine how much pee was in them and I conducted an experiment of my own to see what was the cause of that "classic pool smell". I also presented average amounts of pee in large pools as well as an equation to determine how much pee is in your own pool. PLEASE CONSIDER SUBSCRIBING: http://tinyurl.com/MarkRober-Sub **************************************** I make videos like this once a month all year long while supplies last: CHECK OUT MY CHANNEL: http://tinyurl.com/MarkRober-YouTube FACEBOOK: https://www.facebook.com/MarkRoberYouTube TWITTER: https://twitter.com/#!/MarkRober INSTAGRAM: https://www.instagram.com/markrober/

Frequently Asked Questions

What age is this video appropriate for?

We recommend this video for kids 8 and older. The content is educational and science-focused, but the subject matter — urine in pools, trichloramine, and a brief mention of drinking urine as a cultural practice — is best suited for kids who can engage with it in a mature, curious way rather than just as gross-out humor.

Is there any inappropriate language or content in this video?

No strong or crude language is used. The word 'pee' and 'urine' are used frequently in a clinical, scientific context. There is a very brief TV clip referencing drinking urine as a cultural practice, which some parents may want to address with younger children.

Is this video actually educational, or is it just gross-out content?

It's genuinely educational. The video collaborates with a real University of Alberta researcher and references published studies from Purdue University, explaining concepts like mass spectrometry, chemical tracers, and the chemistry of chlorine byproducts in an accessible way.

Does the video teach kids any bad behaviors?

Quite the opposite — the video explicitly and repeatedly encourages kids not to pee in the pool, and explains the real health reasons why (eye irritation, asthma risk from trichloramine). It models scientific curiosity and responsible behavior.

Are there any scary or violent moments in the video?

The video ends with a brief montage of sound effects including what sounds like a gunshot, glass breaking, and crowd noise, which appear to be unrelated outro clips. These are very brief and not graphic, but parents of sensitive younger children should be aware.

Does the video contain any advertising or sponsored content?

The video briefly shows several packaged food and drink products while explaining which foods contain artificial sweeteners, but this appears to be for educational illustration rather than paid promotion. There are no explicit sponsorship disclosures in the transcript.