No need to punch them; if someone has been exposed to enough dimethylcadmium to describe its odor as "characteristic" they probably don't have long to live...

So older scientific literature is full of all sorts of knowledge that was obtained in ways that are shockingly unsafe by modern standards, including gems like the taste of all sorts of poisons and how large quantities of plutonium are warm to the touch.

My favorite is there are old manuals that recommend smoking while working with cyanide. Allegedly it produces a very disagreeable flavor when you inhale the cyanide through the cigarette, so you get warning to get out of the area*

This was before fume hoods were common, when you would most likely be doing this outside or next to a window

* I have not tested this, and I don't know of anyone who has, so don't rely on what could be an old telephone game for chemical safety

"After venting to release the vacuum, Gerlach removed the detector flange. But he could see no trace of the silver atom beam and handed the flange to me. With Gerlach looking over my shoulder as I peered closely at the plate, we were surprised to see gradually emerge the trace of the beam…. Finally we realized what [had happened]. I was then the equivalent of an assistant professor. My salary was too low to afford good cigars, so I smoked bad cigars. These had a lot of sulfur in them, so my breath on the plate turned the silver into silver sulfide, which is jet black, so easily visible. It was like developing a photographic film."

It's typically only the most toxic that you’d use such equipment to not be exposed at all (but then we tend to avoid those anyways).

You start to recognize the smell of ethers like diethyl ether or tetrahydrofuran (which I love the smell of). Sulfides are obvious (smell terrible).

I made a mistake a couple times smelling things I shouldn’t.

Once was diazomethane gas - a potent akylating agent and explosive. I instinctively put the roundbottom flask to my nose to smell, but realized after how dumb it was. No idea if i heavily alkylated my nasal passage epithelial cells or not, but no side effects.

The other time was a brominated aryl compound similar to tear gas. That was amazingly painful and felt like getting wasabi up my nose despite there being almost nothing left in the flask.

One time which wasn't intention was smelling CbzCl (benzyl chloroformate, a reagent used to add a protecting group to nitrogens). I didn't intentionall smell it, but measured it outside the fume hood in a syringe. It smells pretty awful, but what I realize is that the molecule must bind to your nasal passages (proteins have lots of nitrogens) because I could smell it for the next 24 hours. After smelling it that long, the smell now makes me nauseous pretty quickly.

Mistake!

Only a few years later in chem class did a teacher show how to use your hand to waft fumes from an open beaker or flask so that you can catch a tiny whiff.

It's a low boiling point oxygenated hydrocarbon solvent, so it smells like you'd expect - think things like rubbing alcohol, ethanol (vodka), paint thinner (the ones that have alcohols in them).

Diethyl ether smells very "heavy", for lack of a better word, and pungent. It's almost overpowering, and can become unpleasant after a while.

Tetrahydrofuran (which is just diethyl ether with both ends of the ethyl groups bonded to form a ring) has a "lighter" smell, isn't overpowering and smells "clean" to me. It's still a oxygenated solvent, so it's not pleasant like the smell of flowers or spices, but to me it's more similar to ethanol which is relatively pleasant.

I am left wondering if anything approaching a "standard" exists for smells ...

That would be one hard thing to provide standardized descriptions for - both qualitatively and quantifiably ...

PS. I seem to recall someone somewhere had developed an "electronic nose" ...

... maybe that might be way in.-

You can buy tasting kits for whiskey or wine. They include individual scents like peaty, smokey, oaky, blackberry even some weird ones like band-aid. You can use them to train your nose to deconstruct the smell of whiskey or wine.

It's really eye opening (or nose opening if you will). Since you might even find you suddenly agree with the tasting notes on the bottle.

ie. so called "super-noses" vs. "scent deaf" people.-

As a side note, ether is a lovely smell diluted but inhaled concentrated (for recreational purposes – it's a bit like alcohol in effect) it's bloody brutal, burning your nose & lungs.

(They used to be sweets in the UK called Victory V's which contained a very small amount of ether, and they were just lush. Bought some recently and found whatever additives that was had been removed, oh woe :) )

The task was to say what each of n substances given were in a short enough amount of time, filling out a report. I’m not sure if they still give cyanide to students during exams. That was communist Poland.

100µg is the usual standard of measurement, as in a drop from a vial or a square of blotter, and plenty of enthusiasts like three of those when they partake. So more like 2.5X of a 'standard dose', and well within the typical range.

I'm certain it was a remarkable experience for someone who had no idea whatsoever what they were getting into, though.

> I'm saddened to report that the chemical literature contains descriptions of dimethylcadmium's smell. Whoever provided these reports was surely exposed to far more of the vapor than common sense would allow, because common sense would tell you to stay about a half mile upwind at all times.

As someone that has built and managed clinical laboratories for human samples, I find this article from consumer reports extremely misleading. The describe results as a percentage of a theoretically acceptable level. For example, for cadmium, they are saying an acceptable level is 4.1 ug/day . Then they seem to imply that "TJ The Dark Chocolate Lover's Chocolate 85% Cacao" has 229% of the 4.1ug/day if a consumer ate a 30g piece.

They never actually spell out what they mean or what the actual results they found were, or what the limit of detection of the methodology was or the error range of their tests. I guess they are saying that that chocolate has 9.3ug of cadmium in a 30g sample but it's impossible to say from what they wrote.

The FDA states that the maximum daily consumption of cadmium should be limited to 0.21-0.36ug per kg of body mass. For an avg american male that would mean a threshold of 17.64-30.24ug/day. A typical salad containing 250g of romaine lettuce has 2-14ug of cadmium in it. Lettuce and cereal grains are the most common sources of cadmium in american diets.

The amounts we are talking about are extraordinarily small and difficult to measure. We are talking 5-100 quadrillion individual atoms of cadmium.

https://article.images.consumerreports.org/image/upload/v167... https://www.fda.gov/food/environmental-contaminants-food/cad....

Lettuce has cadmium. TIL.-

> threshold of 17.64-30.24ug/day.

So; it I am not mistaken; by these measurements the amount claimed to be contained in the article, for chocolate; would be within bounds ...

(It's just you then could not go ahead and have a salad :)

It would be really hard to find totally pristine land for a range of crops. Some of the contamination is naturally occurring.

Not sure it matters to monarchs if it’s in the soil verses on plants.

I would be worried about ingesting aerogels until it was proven safe, but it’s an interesting idea.

My immediate rear neighbor behind my house is the organic farm, which is 55-acres, and then the river - so we have a bunch of critters, and that we just have too much attack-on-natural... plus I was born a hippy. I like the bugs.

There is some flimsy evidence that it might affect insects (as in: we drenched the insects in it, and noticed some effect).

And finally, it'll be completely gone within a year or so. Its half-life is around 50 days.

Anything quicker is likely to be orders of magnitude more difficult to pull off, and have unexpected side effects.

I am attempting to do so be (studious) - im open to suggestions if you have any? Did I just stumble into Kindergarten Analysis? (Im not familiar with the field in a professional sense, so I cant determine if what I am saying is stupid)

In this case, however ...

> With this as your discernment lattice

... I wonder if the infrequency of the expression "discernment lattice" would influence the effectiveness of your instructions?

Also I wonder if - as is often reported - the addition of physical, "embodied" activities would not make the results improve even more (ie. "you have a top-of-the field chemistry lab at your disposal with which you conduct all manner of useful experiments" or "based on your hundreds and hundreds of hours of interviews of the subject and other research" or even just (as reported) "breathe deeply and ..."

In short you're saying that the CR numbers are suspicious because they're near the limits of what labs can detect? Is there some source you can provide for this?

I get what you’re saying but I think it’s kind of funny how impossible it is for a layperson to have any clue if that number is a lot or a little.

Then there are[2] multiple orders’ of magnitude worth of chasm that are considered[3] varying degrees of OK if you’re a particle physics experimentalist or radiochemist, nuclear reactor technician, or—worst of all—astronaut. At the high end of that, it starts to matter if you’ve received the dose all at once and in which place of your body and which kind of radiation it was. (I mean the units are supposed to take the last two points into account always, but here those correction factors can start to matter.)

Finally, there are a couple of orders of magnitude where you inevitably and gruesomely die at varying speeds, and after that nobody lived long enough to report.

The chasm is where you get single-percentage-point increases in multi-decade incidence of cancer and such, which is what you probably care about. (Don’t get me wrong, that can amount to a lot of dead people in the wrong circumstances, not to mention infertility.) Fortunately for humanity but unfortunately for your particular question, AFAIK we don’t have enough data to tell with any degree of certainty just how bad any particular point of that chasm is, and there’s no straightforward way to acquire that data.

As far as dramatic death, though, tens of nanograms of polonium inside your body (which is an especially nasty thing to have there) will absolutely kill you dead. That's on the order of 0.1 quadrillion atoms. Of course, those atoms are exceptionally easy to detect, comparatively speaking. As another point of reference, lethal doses of nerve agents are on the order of a milligram and up.

[1] https://xkcd.com/radiation/

[2] https://www.energy.gov/sites/prod/files/2018/01/f46/doe-ioni...

[3] https://en.wikipedia.org/wiki/WP:WEASEL

Food will always taste bland to foul without them, we will suffer from "lifestyle" disorders, and nature will keep dying, until they are returned.

We don't need to know exactly where this person got their degree to understand this.

It's flax. Harvest it before it goes to seed, ret it, break it, scutch it, spin it, weave it, make it into expensive garments. Unless you eat your shirt it's going to be perfectly safe.

I have heard of gallows humour, but its the gallows sarcasm that gets me :-)

To take mercury for example, you can stick your hand in a vat of elemental mercury and be fine. A few drops of dimethylmercury on your skin can be fatal.

On Aug. 14, 1996, Karen Wetterhahn was exposed to dimethylmercury while making a standard for nuclear magnetic resonance studies related to DNA damage.

(...)

It was 5 full months before the consequences of that spill became apparent. Wetterhahn developed stomach problems, then began having trouble walking and speaking clearly. A friend, nurse Cathy Johnson, recalls a lunch date in early January 1997 when she urged Wetterhahn to see a doctor.

Within a few weeks, Wetterhahn was in a coma. On June 8, 1997, she died. She was 48 years old.

I always imagined all such nasty chemicals kill you in a matter of minutes to hours, days at the most. I never imagined they could turn you into a walking corpse. It's up there with Rabies.

Depending on the compound, skipping this step may cause the compound to be relatively inert. This is why, for example, calcium carbonate is a poor source of calcium as a nutritional supplement, but calcium citrate is readily absorbed- the citrate itself is an organic compound, so the body more readily takes it up out of the digestive system and the calcium can be used.

Calcium carbonate will react with stomach acid to form calcium chloride (along with CO2 and water). When given intravenously, calcium chloride is perfectly bioavailable. However, within the small intestines, it has very poor uptake, both through the intestines' active and passive mechanisms. Any remaining calcium carbonate has no uptake at all.

> The general rule is, if you're looking for the worst organic derivatives of any metal, you should hop right on down to the methyl compounds.

I wonder if the dimethyl plays the same role here. Allowing it to cross the blood brain barrier faster

“Drug use in the German military during World War II was actively encouraged and widespread, especially during the war's later stages as the Wehrmacht became depleted and increasingly dependent on youth as opposed to experience.[4]”

A lot of things make more sense about WW2 if you realize most major combatants were on heavy duty drugs during large portions of it.

Just curious: why did Derek Lowe stop writing these ?

Chemistry is complex. Biology, even more so. You can't just say "oh, it contains cadmium", and assume that it's bad.

But of course, even for definitively "toxic" things, one must differentiate between exposure channels. I wouldn't care if I handled a piece of Greenrockite [1], but I wouldn't want to breathe the stuff in powdered form. Same with Cadmium glazes: orange pottery doesn't concern me, but I'd want to be careful if I were handling Cd-containing powdered glazes. You don't want your dry cleaner dumping used methylene chloride in the river, but it's commonly used in decaffeinating coffee.

The reason the author won't work with this particular compound isn't the fact that it contains Cadmium, but rather, that this particular compound has nasty tendencies, in addition to being toxic, that make it particularly dangerous.

[1] https://en.wikipedia.org/wiki/Greenockite

Particularly, wood is fairly recognizable, and almost certainly not liable to spontaneously implode into a cloud of dust. Plus, I'm fairly confident it is biodegradable (even in dust form).

Not sure the same can be said for most other materials, such as cadmium, or the parent mentioned naturally occuring compound.

Lunar regolith or Arean regoliths are quite different. You were presumably talking about lunar regolith.

> Cadmium is bad news. Lead and mercury get all the press, but cadmium is just as foul, even if far fewer people encounter it. Never in my career have I had any occasion to use any, and I like it that way.

It seems clear that he doesn’t want to work with cadmium, regardless of the compound.

I can't speak for the guy, but lots of things are "bad news", colloquially, and yet we work with them in the laboratory as an accepted everyday risk. I am not an inorganic chemist, but I'm pretty certain that they work with far riskier things than inorganic Cadmium on a regular basis.

Where was it that folks found that decaf coffee was eating into their styrofoam cups (decaf alone), so they concluded that the solvents used during the decaffeination process must have been seeping into the coffee ...

I think this is a mistake, though.

I mean, yes, exposure "channels" are absolutely important, but its the (false) assumption that one "safe channel" lowers the general risk of the other channels being an issue.

Your particular example mentions powder - what happens to the substance after it is crushed in a landfill? Or involved in a high speed collision, exposed to high heat, uv rays, microwaved, etc.

Potential harm should include the risk posed by all channels as a function how likely they are to be in that state. If the likelyhood is at 100% over any "reasonable" period of time, then you don't get to ignore the effects of that "channel".

Worse, if any of the channels are difficult to detect, then the risk should be compounded - I know about wood dust and can both easily see it and am amply aware when it is an issue and can take precautions. I'm not sure I can even identify the material you mention nor would be able to distinguish it from just "normal" dust.

A decade ago or so there was an application for RoHS exemption for the use of cadmium in displays, and their argument was that because coal plants emit cadmium, and because Oled screens with cadmium quantum dots are so much more efficient than backlit screens, that in practice allowing the use of cadmium in screens would reduce total cadmium release into the environment. It didn't pass.

They were pretty common.-

Its probably a good idea to avoid drilling, sanding, or filing things that may have Cadmium in them if you're dismantaling old electronics, lets you inhale it.

"et alia" is used to refer to "the others (people)" whereas "et cetera" is used to refer to "the others (things)". So you'd use "et cetera" to refer to the other posts. But if you were writing a list of authors you might end with "et al." to indicate that there are more.

I know correcting somebody's Latin usage is really pedantic even by HN's standards. I'm only saying it cause I find it interesting and want to share, not because I want to correct you :)

https://en.m.wikipedia.org/wiki/Et_cetera