Sciencemadness Discussion Board

Would you feel comfortable using aniline and n,n-dimethylaniline (possible carcinogens) in a home lab?

Cou - 28-7-2020 at 17:35

I just received 500 mL of n,n-dimethylaniline for use as a base in the reaction of tertiary alcohols with acid chlorides to form esters. It required hazmat special packaging. Seems to be pretty unhealthy, from looking at MSDS.

It came as a glass bottle wrapped inside a metal can. Even with all the layers of packaging, I immediately noticed the amine smell when I cracked open the metal can. I believe our noses are very sensitive to amines, so we notice their smell even in safe concentration.

Would you feel comfortable using this? I don't have a fume hood, but I use a heavy duty fan outdoors.

[Edited on 7-29-2020 by Cou]

draculic acid69 - 28-7-2020 at 18:32

Heavy-duty fan outside should be ok.wear a mask, disposable nitriles gloves and cover yourself up.

karlos³ - 28-7-2020 at 19:29

Yes I would.

B(a)P - 28-7-2020 at 19:34

With respiratory protection and the usual laboratory practices n,n-dimethylaniline is quite safe to handle. I believe it is double packed because it is a bit of an escape artist as you have discovered. By example it is far less toxic than its evil cousin 2,4 dimethylaniline.
The short term exposure limit (STEL) is a limit derived by your local EPA or equivalent that if not exceeded affords reasonable protection to the hobby chemist. It is generally a bit meaningless because the hobby chemist would rarely have the means to monitor air quality. However, it can help to give you an understanding of relative toxicity to compounds you are more familiar with. Be aware the STEL will change from one jurisdiction to the other depending on the adopted method for quantifying risk. I have provided a few below for you to get an idea of the relative toxicity of n,n-dimethylaniline (including the authority that derived the exposure limit).
n,n-dimethylaniline - 50 mg/m3 (NIOSH)
benzene - 3.2 mg/m3 (ACGIH)
toluene - 560 mg/m3 (NIOSH)
ethyl ether - 1500 mg/m3 (OSHA)
ethyl bromide - 1100 mg/m3 (OSHA)

unionised - 29-7-2020 at 04:55

I'm fairly happy using* alcohol- a known human carcinogen.

*Either Use of the word.

Metacelsus - 29-7-2020 at 05:10

I made toluidine in a home lab in the past. As long as you have good ventilation (fume hood or outside) it should be reasonable safe.

Syn the Sizer - 29-7-2020 at 06:59

I would and do plan on using it in the future. I am interested in synthesizing they methyl family of indicator dyes and N,N-dimethylanaline is the main reagent used in all of the.

For methyl red it's N,N-dimethylanaline, sodium nitrite, and anthranilic acid.

Dr.Bob - 5-8-2020 at 17:23

While many anilines are toxic, only a few are highly toxic, so as long as you are careful, you should be OK. The dianilines and biphenyl ones are much worse, as they are so carcinogenic. But simple anilines are not so bad. They also turn dark quickly, but that can be from as little as 1 ppm of oxidation products, like N-oxides. But if you want to clean after anilines, just wash with mild acid and then bleach, to remove any traces.

For years I have seen people worry about anilines being so bad, but there are anilines in the structures of many of the most common and useful drugs. Not to safe they are all safe, but not all are bad. There are some that are quite safe to use, and others that are truely dangerous, but most fo those are not common or easy to buy or make now.

zed - 10-8-2020 at 00:31

Umm. Something I think about. Some are just fine, while others may be quite toxic.

Gotta check, and consider on a case by case basis.





Might expect acetanilide to be about as toxic as Aniline. But, probably not.

Crotamine, is OK to slather on your skin.

PABA, no problem.

Paracetamol, aka Tylenol, not too toxic.

Try being flamboyant with some other members of the family, and you will sicken and turn Blue.

Sigh, so many possibilities to ponder.

Build a fume hood.

[Edited on 10-8-2020 by zed]

[Edited on 10-8-2020 by zed]

fdnjj6 - 10-8-2020 at 21:48

Idk. I just made nitrotoluene and treated it like liquid cancer. Still, I ended up catching a few whiffs of it. Granted it was only 1-4 seconds each time but it happened probably max of 10 times. I had a respirator on during the separation as well as most of the cleaning but it's damn near inevitable. The only reason I felt okay using it was because its odor threshold is very low. 0.05mg/L and the odor is very distinct. I went through 10 pairs of nitrile gloves, had a boiler suit on that covered me almost completely, and a proper respirator for the actual cleanup and synthesis. When I washed and bagged up the gloves that were used and threw them in the trash (I only did this since it's a minimal amount of the nitrotoluene) the trash can ended up smelling like it if you were throwing something away. I let it air out with the top open and double bagged it. That should take care of it. Still shows that even when you least expect it you'll still get exposed at some point. So I guess that's the risk you'll just have to take. I just wish it'd be easy to know if such a small exposure is actually worth worrying over.

fdnjj6 - 10-8-2020 at 23:38

Quote: Originally posted by draculic acid69  
Heavy-duty fan outside should be ok.wear a mask, disposable nitriles gloves and cover yourself up.

Yea use a respirator with proper filters for sure and don't just go with just a fan outside. Fan and respirator outside is the way to go. I made nitrotoluenes like this and even with the fan and outside, the fumes are everywhere and a respirator is required. It has a very low odor threshold of 0.05mg/L and so it's easy to smell it. I would not have done it without the respirator.

I ended up being exposed to it a few times during stuff like disposing of the gloves. I was able to smell it. Right away exhaled and walked away or put on filters. The stuff is oily too and while it is volatile, it's a PITA to clean off. I washed my glassware 6-8 times with water and acetone and I still was quite a bit skeptical. The lab stand had some spill on it and I tried washing it away with acetone but it still smelled like MNT. It with the glassware has been sitting outside for a full day now and I'll be checking on it probably tomorrow. I'll wash the glassware with water one more time, take apart the lab stand and wash it with lots of water and soap, and maybe another round of acetone, and that should be good.

When it comes to carcinogens, I am very paranoid. I already opted out of dichromates but nitrotoluenes are relatively potent as well. While my exposure was short and acute, I am still always left worrying if I just gave myself cancer. I always think I'm way more likely to get it from other crap in everyday life but who knows?

1 in 3 people will develop cancer in America, so the chances of getting it are pretty high. I'm not sure if I really should be worrying about a total combined exposure over 24 hours of 1 minute of medium amounts of MNT through inhalation where most of the time I never even deeply inhaled it and realized it right away and blew away. But sometimes I still do worry. The main scary part is the lack of testing on such chemicals. Most of the time we don't even freaking know if these things can actually cause cancer in humans. There are soooooo many factors involved and cancer is something that is so common naturally that it makes it just so difficult to fully comprehend/test the chemicals.

All I know is that I did not take the chemical lightly and that I will be using it up ASAP. While it is said that nitrotoluene isn't as bad as nitrobenze, it's still nothing laughable. A 3 for health on the NFPA diamond is often not something to scoff at.

So I guess long story short, full PPE, outside, fan, respirator, switch gloves out often/as soon as something spills on them, wash equipment thoroughly, store very well, and use things up ASAP.

I wish there'd be an easy table of chemical's cancer potential to differentiate between ethanol and analine. It'd take out so much guess work. No one would wear full PPE and a fan and do stuff outside for ethanol. As long as you don't abuse it, your chances of cancer are negligible. Nitrotoluenes, are classified as probably carcinogenic while ethanol is confirmed carcinogen. Yet, you can drink a lot of ethanol and be fine, but drink nitrotoluene now and then and you'll either die from acute poisoning or likely develop cancer.

I think the tests done on mice was where they put around 2000-5000 ppm of nitrotoluenes in their food for 13 weeks. Only the o isomer caused cancer in female mice or something like that. Carcinogens are so selective and have sooo many factors it's not even worth measuring. Although an Meh to OhShit scale would be nice.

BrainAmoeba - 11-8-2020 at 01:23

I would with proper safety equipment.

Sigmatropic - 11-8-2020 at 13:10

We are missing the point why some anilines are such potent carcinogens and others are not.

I've once understood, I'm sorry my toxicology book is out of reach and probably does not cover the subject thoroughly enough to go into this detail but here goes :

Some anilines, especially electron rich ones, undergo bioactivation. First being converted into the hydroxylamine then O-sulfonated or O-acetylated, typical two stage biotransformation. But then that hydroxylamine O-sulfate/ester can then go on to produce reactive quinone imines methides in the case of appropriately positioned alkyl groups (2,4-dimethyl aniline for example). Alternatively the hydroxyl amine can again be oxidized to the nitroso compound which is also carcinogenic.

It is for this reason there is no point in comparing acetanilide and other N-acyl anilines with free anilines. Those N-acyl anilines simply aren't transformed into the active carcinogenic compounds at levels high enough to matter.

zed - 13-8-2020 at 19:26

Carcinogens? I wasn't really thinking about that. More concerned about dropping dead on the spot.

fdnjj6 - 13-8-2020 at 20:03

I'd also like to revise my previous post, (I can't edit for some reason).

A fan outside is not enough to be working with very toxic things. I managed to expose a family member to nasty chemicals doing exactly this. I know for sure it was the chemical I was using because they had the exact symptoms. So I'd say if it's too toxic for you to handle without full PPE, don't do it.

chemist1243 - 21-10-2020 at 12:27

We are mad scientists. We handle dangerous chemicals, some of which cause cancer or are toxic in minute quantities.

The truth is, you probably are at higher risk of cancer when filling up your gas tank than your are handling aniline using gloves and safety goggles. Be smart. Dont eat any. Dispose of waste properly. Wear gloves. Pay attention to what your doing at all times. Have good ventilation. You will be FINE if you do these simple things.

Personally i have no use for aniline, so no, I wouldn’t use it in my home lab. But if i did I’d go ahead and strap on a pair of gloves and have fun, like i always do. Carcinogens are often some of the most useful and interesting chemicals you will ever work with, so dont get cold feet over a few carcinogen warnings that only pertain to those being irresponsible and not following basic rules of safety.