Things I won't work with: the higher states of bromine (2019)

My PhD supervisor would wash his teeth over the sink where we'd rinse all the gel preparation tools. He got throat cancer in his 50s and died soon after my PhD defense.

- "attaches itself to the DNA particles"

This is why it's a known mutagen with a long list of very specific, strident toxicity warnings. That's the organic cation, though; compared to that, the Br- anion is utterly benign. You're looking at the wrong hazard!

Br- is a standard counterion in human-approved drugs (those formulated as HBr salts).

https://www.google.com/search?q=hydrobromide+site:drugbank.c...

Add the EtBr after you microwave the agarose

I also had to prepare agarose gels with EtBr in the past, but now there are several alternatives for gel staining, such as SYBR Green.

The author actually has an article on that specific compound. https://www.science.org/content/blog-post/myth-ethidium-brom...

Not saying chronic exposure can never have adverse effects

Last night I somehow dreamed I had a hydrofluoric acid burn. Reading this thread I remembered there was this rust stain remover product on US Amazon that is 3% HF. https://www.amazon.com/product-reviews/B000LNQNM0/

It's got great reviews (and I'm inclined to believe that this product will do the job). There's one 1-star review that stands out though: "Simply put. It doesn’t work and it was shipped leaking." Yikes!

"Improved" fire suppression systems contain hydrofluorocarbon gases which when burned decompose into HF gas. What could possibly go wrong?

Do NOT stay in the server room (or armored personnel carrier) when the fire suppression system goes off. https://academic.oup.com/milmed/article/177/1/108/4345530

It's the first thing in the series: https://www.science.org/content/blog-post/things-i-won-t-tou...

HF has actually been used right out of the cylinder for a long time in Merrifield peptide synthesizers. It's the traditional way to cleave the peptide off the resin at the final step, so there are actually a lot of people who've used the stuff. But it's in a dedicated apparatus that is (that had better be) well sealed, and people treat it with due respect. At a former employer of mine, there was an accident with one of these machines right before I joined the company. The shout "HF LEAK!" went out into the halls, and I'm told that the whole area set a never-to-be-equaled evacuation record.

My dad had some interesting-acid stories, when he was a young chemist. They both involve cleaning glassware. The era is around 1970.

One was something he said resembled a wok full of the usual suspects of strong acids. Overnight, the mixture was hygroscopic, so they'd start it heating up in the morning to dehydrate it and increase the concentration. To test if it was ready, they'd throw in a small piece of wood, about the size of a match. If it disintegrated on contact, it was ready. Then you could dip your glassware to clean it.

But, in another lab, they would use a small bottle of hydrofluoric acid at the bench, taking a layer off the glass at the same time. While the dangers of large exposures were well known, he did mention the nerve damage and it being highly annoying and painful if trace amounts got under your fingernails, a somewhat common injury of the lab that everyone simply tolerated.

He thought the latter was a more convenient arrangement.

If you want to read an amazing book from someone who sails the other tack and lovingly creates rocket propellants: https://library.sciencemadness.org/library/books/ignition.pd...

I know nothing from chemistry apart from high school stuff decades ago (and wasnt very good at it), but oh boy Derek knows how to write interesting stuff for laymen, read whole series since it gets quite regular mentions here.

This is how you make people interested in more difficult topics

I love how many of those blog posts are triggered by German articles. German chemistry: the best outcome is setting grant money ablaze.

Ah yes the timeless classic which at the end calls out an idiot company for offering something that explodes at -180C in commercial quantities :D

Every clown that gets cavalier with safety rules should read the story of Karen Wetterhahn.

I don't understand what you are saying. Karen Wetterhahn meticulously observed all known precautions at the time. Her death was terrible, but as far as we know zero "clowning" was involved. Shouldn't someone who "gets cavalier with safety rules" study cases where someone gets hurt after they "gets cavalier with safety rules"? There is plenty of those.

The lesson of the Karen Wetterhahn incident is that "Do everything right and by the book? The gru can steal eat your face." Not really the thing clowns should focus on.

Wetterhahn

Who, just to be clear, was not being cavalier, but followed all the relevant precautions known at the time. They were just inadequate.

The very first day I showed up for grad school, the entire hospital was closed off by men in hazmat suits and a bunch of firefighters. I proceeded to the central office of my program, where more men with hazmat suits were wandering around, and a guy was being treated in my program's office for injuries.

It turned out they were doing "spring cleaning" and somebody accidentally jiggled an old bottle of ether in a fume hood, and unfortunately the old ether must have had some free radicals, which led to an explosion. It blew out all the windows in the room (which were 20-30 feet away) and the chemist was only saved because he was wearing safety equipment (he still had permanent scars on his face years later).

That room was later my office! The incident (as well as the investigation) is written up here: https://synapse.ucsf.edu/articles/2019/03/24/date-ucsf-histo...

My strongest memory of high school chemistry is inhaling bromine vapors (I'm sure we were doing various addition reaction common in organic chemistry). It's got a very specific smell, rarely if ever encountered in the regular world.

The same chemistry lab had a sign warning us not to "pipette by mouth", but I actually do that today to transfer tardigrades. It gives you remarkable control over the volume transferred.

That is a strong indictment of US teacher training. (One assumes that's the US, because teachers are remarkbly untrained over there.) Everyone knows you deactivate bromine and chlorine with thiosulfate or sulfite and only then chuck it down the drain.

Kind of like alchemy. Except alchemy would kill you very slowly with heavy metal poisoning, and this stuff would kill you very very fast in multiple ways.

That story is bonkers. I don't know how any student of chemistry mistakes a rocky crumbly cream-colored solid for an extremely hazardous red-orange liquid with a literal aura of evil wafting off of it.

Yep, that's it. A lot of links to other blog posts on older posts are broken, but you can usually change the "blogsdev" subdomain to "blogs" and it'll work.

Typo aside, that's one of the more clarifying similies I've ever read.

Or at least, for anyone who grew up on Jurassic Park: https://m.youtube.com/watch?v=WgQe68kF_8M&t=31s

Xenon difluoride is in fact not hard to make: mix xenon and fluorine and expose to sunlight (or an artificial UV source). It just wasn't done for the longest time because of preconceptions.