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Author: Subject: H2S intoxication
IrC
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[*] posted on 5-11-2011 at 00:23


What about building a detector based on the Figaro gas sensor TGS825 Hydrogen sulfide (5-100ppm)? I did using the little Pic PIC12F683-I/P, a TGS825, and a programmer development setup I have. I just like to know these things. Mostly because as madscientist said it was likely more panic attack. It happened to me once. I for work related reasons reversed engineered the 'enemy' electronics and I typically had a bucket of methylene chloride sitting around with some board or other in it all the time and I never worried about things. Several years of doing this later I studied up on the depotting solvent and learned it was flooding my blood with monoxide. A few months later I started having severe panic attacks which actually forced me to stop using the chemical. I never have had it since. I know in my mind for years I had no trouble being most cavalier with the stuff but after too much study of how breathing it results in nasty things in your blood I just could not use it anymore. Not only that but on a trip taking an old International truck from Phoenix to Billings with an exhaust leak so severe I was too sick, dizzy, and nauseated to drive halfway through Idaho. I went to an emergency room and all they did was stick a red laser sensor on my finger and say 'gee your blood O2 looks really high'. Stupid doctor I thought. I asked him since all their device was doing was shining a laser through my finger to measure how red my blood was how the hell would they know it I was dying or not? I actually had to explain to the doctor how his equipment worked and relate this to the fact that CO binds the blood making it even redder than normal. So the closer to death you are the better they think you are! I explained to him that only by testing arterial blood gasses could they know. This guy had a medical degree and neither him or his nurses understood how or why their equipment worked nor did they understand they were in error on the side of killing their patients. Needless to say after breathing fresh air for 3 hours I felt better anyway so I left and slept in the truck with the motor off until morning when I went around getting the parts to fix the exhaust system myself allowing me to finish my trip with no further illness.

About a month later I started having similar panic experiences with CO in general. At home even thinking about my furnace started being a problem. I started researching gas sensors (at the time there were none at Walmart or similar places for sale) and came upon Figaro. I ordered a CO sensor and when it came in the mail completed my first warning alarm device the same day. I designed it to either plug in the wall or use a cig lighter plug so I could take it on cross country driving trips. Still have it. I designed in a sensitivity control to where it will even detect someone smoking in the room from the monoxide. I will say it was surprising to learn in the winter you have more CO floating around than you might realize, but it did explain some of the red I see in peoples faces in the winter.

No mind over fear approached worked for me. Science over fear did. This was around 91 or 92 and Figaro was just starting so CO was about the only sensor they had. Today they have many covering a large number of various gasses. Nothing beats the calming effect of actually measuring and knowing for sure the types and amounts of gasses around you.

Right now they list sensors for:

LP-Gas/Propane (500-10000ppm)
Natural gas/Methane (500-10000ppm)
General combustible gas (500-10000ppm)
Hydrogen (50-1000ppm)
Carbon monoxide (50-1000ppm)
Ammonia (30-300ppm)
Hydrogen sulfide (5-100ppm)
Methane and Carbon monoxide
Alcohol, toluene, xylene (50-5000ppm)
CFCs (HCFCs and HFCs)
R-22, R-113 (100-3000ppm)
R-21-R-22 (100-3000ppm)
R-134a,R-22 (100-3000ppm)
Other refrigerant gases
Indoor Pollutants
Carbon dioxide
Air contaminants (<10ppm)
Automobile Ventilation
Gasoline exhaust
Gasoline and diesel exhaust
Volatile vapors from food (alcohol)
Water vapors from food
Oxygen

Something to think about. As cheap as these sensors are now and considering how simple an alarm circuit is to build I think it makes sense to have such a capability in your mad science lab.

But that is just me.

Edit: I guess a link would help.

http://www.figarosensor.com/gaslist.html


[Edited on 11-5-2011 by IrC]




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[*] posted on 5-11-2011 at 03:15


Klute wrote that he used "50mg in 1mL" of sodium nitrite. Did he use 1 mL shot containing 50 mg? That's 4.76% solution (0.05 g of the salt in 1.05 g of the solution), and the appropriate percentage is 3%, used as IV push of 0.35 ml/kg.
Na-nitrite is usually given as prepared 10 mL 3% shots during 3 minutes, and it has to be pure salt, not this 90% he mentioned.

Am I mistaken to feel like he could've done less harm to his veins or his heart/brain if he just went outside, breathing deep and calm?
If a person is conscious enough to prepare a solution and administer it intravenously, I'd say the intoxication is not great, and fresh air is enough.
Sodium nitrite shots are typically given by ER personell upon finding someone lying on the floor unconscious or twitching, and there's a stink of H<sub>2</sub>S or similar blood poison (HCN). Or when there's evidence to support cyanide salt intoxication, etc.

I think he just had panicked and that could've killed him.
If one can prepare a nitrite shot, one can build a freaking fume hood, too.

[Edited on 5-11-2011 by Endimion17]




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[*] posted on 5-11-2011 at 08:13


That's quite an accident. I've worked with H2S before as well, small quantities though. I wondered if I should handle it in a fume hood or outside. I decided to handle it outside, because I was working with very small quantities.

I made an H2S generator that could be loaded in less than 10 seconds to limit exposure to the gas.

The problem came when I had to open up the generator, and when I had to collect the product when the synthesis was over. Some gas was still in the generator and some un-popped bubbles floated above the product.

The smell was atrocious, but the concentration was low enough not to knock out my sense of smell (I thought). The whole time I carried around a vial of vinegar to be sure my sense of smell was not knocked out.

Then I smelled the vinegar I brought along, and smell was only half as strong. That's when I knew I had to get the hell out of there. Then my hands started shaking, more from fright than from anything else.

I'm curious though, how long did it take for your sense of smell to recover? It took me an entire day before I could smell anything properly.

I would also advise anyone even THINKING about doing this, to reconsider.

@ Endimion17, having worked with this before, I can assure you that "fresh air" is hard to come by when you lose control of H2S. It hugs the floor, so you'd have to climb a tree (if you're outside) to get away from it. If you did this in a building you'd have to find a safe place upstairs, or on the roof. Even worse, it hugs the bottom of you lungs, so you need to do a handstand against a wall to get every last bit of gas out of your lungs. Then again, it's hard to do a handstand when your hands are shaking.




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[*] posted on 6-11-2011 at 11:31
H2S for suicide


A few months ago, before I knew about this forum, I read an article in the New York Times about a recent fad in Japan of committing suicide. I'm not sure I remember exactly what was in the article and what I learned about it after some internet research, but the article made it clear that there had been some suicides using some kind of gas, that sometimes there were worries that neighboring apartments and houses would be affected by the gas, and that the author of the article didn't want to reveal the recipe for fear of facilitating more suicides. Then I took some clues from the article and googled on suicide methods and put the pieces together, which made it clear that it was H2S that was being used, and that it was being produced by mixing toilet bowl cleaner (for the HCl content) with some kind of sulfur compound. I was thinking to myself, if they only knew how easy it is to make FeS. I also found it creepy looking at one of the suicide web sites, there were people who were so depressed they were begging for help in doing it cleanly.

I'm not sure I would use H2S if I wanted to kill myself, I always assumed CO would be the most painless.




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[*] posted on 6-11-2011 at 12:44


Quote: Originally posted by annaandherdad  
I'm not sure I would use H2S if I wanted to kill myself, I always assumed CO would be the most painless.


It's also scary how easily CO can be generated. The dehydration of formic acid via H2SO4 will yield appreciable amounts of CO. There are a million ways to die, H2S is just a smelly one.

A simple google search can turn up more info than a suicidal person should know. These people are stubborn, the author's efforts were in vain.

I have a friend who has an old dog in pain, but he does not want to put him to sleep because it's outrageously expensive >$500.
I told him that formic acid with H2SO4 yields CO, so he can put out his dog without paying someone else to do it.




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[*] posted on 6-11-2011 at 13:03


Yes, a guy associated with one of the research groups where I work was recently killed by CO from a faulty heater. I don't think it was at home, I think it was out at some research station.



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[*] posted on 6-11-2011 at 15:10


Quote: Originally posted by White Yeti  
@ Endimion17, having worked with this before, I can assure you that "fresh air" is hard to come by when you lose control of H2S. It hugs the floor, so you'd have to climb a tree (if you're outside) to get away from it. If you did this in a building you'd have to find a safe place upstairs, or on the roof. Even worse, it hugs the bottom of you lungs, so you need to do a handstand against a wall to get every last bit of gas out of your lungs. Then again, it's hard to do a handstand when your hands are shaking.


No, you don't have to climb a tree. There's always a breeze.
I'm curious how is it possible to create so much hydrogen sulphide. I always had trouble with that and my apparatuses were neat and tight. No wasting, and if I need to open something, I did it outside.
I simply don't understand how can these things happen unless someone has a faulty gas cylinder. Where do you people get so much acid soluble sulphides?

And no, it does not hug the bottom of the lungs. That's an annoying myth associated with breathing helium and sulfur hexafluoride.
Lungs are not empty bags to allow gases collecting inside. They're made of porous tissue and if they're filled with a foreigh gas, few generous breaths are enough to get rid of them.
The handstand thing is completely unneccessary.



Quote: Originally posted by annaandherdad  
A few months ago, before I knew about this forum, I read an article in the New York Times about a recent fad in Japan of committing suicide. I'm not sure I remember exactly what was in the article and what I learned about it after some internet research, but the article made it clear that there had been some suicides using some kind of gas, that sometimes there were worries that neighboring apartments and houses would be affected by the gas, and that the author of the article didn't want to reveal the recipe for fear of facilitating more suicides. Then I took some clues from the article and googled on suicide methods and put the pieces together, which made it clear that it was H2S that was being used, and that it was being produced by mixing toilet bowl cleaner (for the HCl content) with some kind of sulfur compound. I was thinking to myself, if they only knew how easy it is to make FeS. I also found it creepy looking at one of the suicide web sites, there were people who were so depressed they were begging for help in doing it cleanly.

I'm not sure I would use H2S if I wanted to kill myself, I always assumed CO would be the most painless.


Those are the infamous "detergent suicides" that became popular in Japan.
We had one case in Croatia almost exactly a year ago. A guy was found dead in car labeled with warnings in the middle of a field. The car was loaded with the gas produced by a mixture in buckets inside the car.
I sincerely doubt it was a clean suicide because his finger was found on a street in another city and one lady saw him wandering around with a bloody hand. He supposedly told her there's no sense living without a finger. :(
I don't have any updated information, but the whole case was extremely weird and upsetting. He was quite introverted, as I learned.

[Edited on 6-11-2011 by Endimion17]




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[*] posted on 6-11-2011 at 15:45


Quote: Originally posted by Endimion17  
There's always a breeze.
I'm curious how is it possible to create so much hydrogen sulphide...Where do you people get so much acid soluble sulphides?
[Edited on 6-11-2011 by Endimion17]


You'd be surprised with how long the rotten egg smell sticks around, even with a slight breeze. Stupid as I am, I chose one of the worst days to perform the synthesis, 0 wind. It took about half an hour for the smell to disappear.

To answer to your second question:
You can create VERY large quantities with Al2S3. I performed a synthesis with about a gram of Al2S3, which when reacted with water can generate about half a litre of H2S, enough to kill several people.

Most people opt for the classical FeS+HCl generator, I prefer the H2O+Al2S3 alternative.




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[*] posted on 24-7-2012 at 13:00


Wanted to share with every one, another (biological use) for H2S. Sorry link;

http://www.ted.com/talks/mark_roth_suspended_animation.html
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[*] posted on 24-7-2012 at 15:04


Yes, H2S can be used for inducing suspended animation. But the guy doesn't give much details about his liquid version of H2S that can be delivered to a patient intravenously.

Does anyone have any guesses as to how one would accomplish such a feat?




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[*] posted on 24-7-2012 at 16:50


If my memory serves me correct, it was a combination of inhaling low concentrations in air, accompanied by freezing of the body. Timing, order, and a number of variables were all important factors for success. There had been many failures in the past.
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[*] posted on 26-7-2012 at 16:05


Wait, isn't intraveinous sodium nitrite used to treat cyanide poisoning? I had no idea it also worked for H2S.
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[*] posted on 26-7-2012 at 16:40


Quote: Originally posted by liquidlightning  
Wait, isn't intraveinous sodium nitrite used to treat cyanide poisoning? I had no idea it also worked for H2S.


More elegantly, and more easily titratable. And also less risk of neoplasm, they use Amyl Nitrite, commonly known as poppers. Who said NaNO2 was used to treat CN- intoxication? I guess both substitute in RBC's, but different mechanism.

I don't think you are serious, but I may be wrong.
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[*] posted on 26-7-2012 at 16:42


Quote: Originally posted by White Yeti  
Quote: Originally posted by Endimion17  
There's always a breeze.
I'm curious how is it possible to create so much hydrogen sulphide...Where do you people get so much acid soluble sulphides?
[Edited on 6-11-2011 by Endimion17]


You'd be surprised with how long the rotten egg smell sticks around, even with a slight breeze. Stupid as I am, I chose one of the worst days to perform the synthesis, 0 wind. It took about half an hour for the smell to disappear.

To answer to your second question:
You can create VERY large quantities with Al2S3. I performed a synthesis with about a gram of Al2S3, which when reacted with water can generate about half a litre of H2S, enough to kill several people.

Most people opt for the classical FeS+HCl generator, I prefer the H2O+Al2S3 alternative.


Had you reacted that with methanol, would you have made methyl mercaptan? Can you share your facile aluminum sulfide synth. thanks.
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[*] posted on 26-7-2012 at 17:18


Quote: Originally posted by Fennel Ass Ih Tone  
Quote: Originally posted by liquidlightning  
Wait, isn't intraveinous sodium nitrite used to treat cyanide poisoning? I had no idea it also worked for H2S.


More elegantly, and more easily titratable. And also less risk of neoplasm, they use Amyl Nitrite, commonly known as poppers. Who said NaNO2 was used to treat CN- intoxication? I guess both substitute in RBC's, but different mechanism.

I don't think you are serious, but I may be wrong.


Here's a link. I am serious. http://en.wikipedia.org/wiki/Cyanide_poisoning#Treatment_of_...
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[*] posted on 27-7-2012 at 05:55


wanted your synth for Al2S3, mainly. Is it potentially an explosive sulphide?
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[*] posted on 27-7-2012 at 08:33


Quote: Originally posted by Fennel Ass Ih Tone  
wanted your synth for Al2S3, mainly. Is it potentially an explosive sulphide?



Al2S3: direct union of elements in a crucible. Light stoichiom. mixture with Mg ribbon or such like. It’s quite spectacular. Al2S3 then solidifies into fairly soft material (much softer than Al2O3, quite smelly (H2S). With water, H2S is slowly generated, faster with dilute acids. It’s not at all explosive.

This reaction is also used as a heat booster for technical Si via silicon thermite.




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[*] posted on 27-7-2012 at 09:40


Quote: Originally posted by chief  
I have a rat-problem, _now_. And poison does not come into account, because of the stinking and rotting cadavers in the holes !
The rat(s ?) are under a 2-ton brickwall-waste, and their "home" has at least maybe 4-5 visible entrances. Now I heavily think of what to do ...
because it's also a indoor-problem !


First, I will state it is a bad (and dangerous) idea to concoct poisons yourself. But, if you nevertheless decide to do something on your own, I would point you (I have no professional background or experience in extermination) in the direction of Copper (II) Oxygen Chloride, 3Cu(OH)2.CuCl2, or Basic copper sulfate, CuSO4.3Cu(OH)2 H2O, or Copper ammonium carbonate, all of which are used in fungicides (after carefully formulation with dispersive and filler agents). FYI, here are some reactions between Hypochlorous acid and Copper forming 3Cu(OH)2.CuCl:

HOCl + 2 Cu --> Cu2O + HCl

2 HOCl +2 Cu --> Cu(OH)2.CuCl2

4 HOCl + 2 Cu2O --> 2 CuCl2.Cu(OH)2 + O2 (g)

An interesting route to preparation would be to add copper filings to a dilute solution of Sodium bisulfate and Bleach (NaClO) forming HOCl. Any Cu(OH)2.CuCl2 formed could be converted into Basic copper sulfate. Also, some comments from "Modern inorganic chemistry" by Joseph William Mellor:

"R. Chenevix notes the ready solubility of cupric oxide in chlorine water, and P. Grouvelle found that the soln. obtained by passing chlorine into water with cupric oxide in suspension possessed bleaching properties, and these were retained even after the soln. had been boiled for a quarter of an hour. A. J. Balard found that the distillation of P. Grouvelle's liquor furnished some hypochlorous acid and a green oxychloride, 3CuO.CuCl2.4H20, was formed in the retort. A. J. Balard prepared a soln. of cupric hypochlorite by dissolving cupric hydroxide in hypochlorous acid. It is also made by the action of cupric sulphate on calcium hypochlorite. A. J. Balard found that copper filings are partially dissolved by hypochlorous acid, the soln. after standing some time contains cupric chloride, and deposits a green pulverulent cupric oxychloride."

Here is a paper describing the preparation of Basic copper sulfate, "The Preparation and Effectiveness of Basic Copper Sulphates for Fungidical Purposes", Link: https://docs.google.com/viewer?a=v&q=cache:fsGty_h63WkJ:...

Copper salts cited above are not overly toxic to people (see http://pmep.cce.cornell.edu/profiles/index.html and search under CuSO4, or go directly to http://pmep.cce.cornell.edu/profiles/fung-nemat/aceticacid-e... ), but certainly use gloves and limit inhalation. Per Wiki at http://en.wikipedia.org/wiki/Copper_toxicity "With an LD50 of 30 mg/kg in rats, "gram quantities" of copper sulfate are potentially lethal in humans." However, Cu salts can apparently be deadly to fish, dogs and lower organisms including fungus. My attention to this fact occurred (on another website) when someone was asking how to cleanup a fish tank after an accidental copper poisoning that killed 'everything' in the tank. Source was a new brass fitting (a copper alloy) that reacted with an ammonia buildup in the fish tank's oxygen rich water attacking the brass and producing a soluble and apparently very toxic Copper compound (a guess, Copper ammonium carbonate).


[Edited on 28-7-2012 by AJKOER]
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[*] posted on 29-7-2012 at 12:27


Quote: Originally posted by blogfast25  
Quote: Originally posted by Fennel Ass Ih Tone  
wanted your synth for Al2S3, mainly. Is it potentially an explosive sulphide?



Al2S3: direct union of elements in a crucible. Light stoichiom. mixture with Mg ribbon or such like. It’s quite spectacular. Al2S3 then solidifies into fairly soft material (much softer than Al2O3, quite smelly (H2S). With water, H2S is slowly generated, faster with dilute acids. It’s not at all explosive.

This reaction is also used as a heat booster for technical Si via silicon thermite.


Thank you! So would Al2S3, or better yet, zinc sulphide, react w/ methanol to yield the primary mercaptan? zinc sulphide more robust? how's the synth go or recommended (ghetto). Please, and thanks mucho gracious.
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[*] posted on 29-7-2012 at 12:55


No idea about mercaptans, never really thought about it much. Al2S3 is definitely the more reactive of the three mostly in use in H2S generators (Al2S3 > ZnS > FeS).

With methanol H2S and Al methoxide should be formed, not MeSH:

Al2S3 + 3 MeOH ====> 3 H2S + Al(MeO)3.

I think.




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[*] posted on 29-7-2012 at 15:25


I imagine PS5 plus the alcohol would render a thiol. ?
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[*] posted on 30-7-2012 at 05:00


You mean P2S5? No idea...



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[*] posted on 30-7-2012 at 07:36


Quote: Originally posted by blogfast25  
You mean P2S5? No idea...




Yais. Not that just anyone would be able P2S5, but with methanol? Methyl Mercaptan?
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[*] posted on 30-7-2012 at 09:32


I used TFSE, and got many an insight, tnx.
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[*] posted on 30-7-2012 at 14:24


Yup, phosphorus pentasulfide gives mercaptans with alcohols.
I don't think this is a popular preparative route, though, probably because of the ubiquitous nature of thiourea. This is used to form isothiouronium salts (from alkyl halides) and then these are hydrolyzed.

Toxcity, toxicity...ahh yes. I was one of the generation whose chemistry career kicked off with the infamous "The Golden Book of Chemistry Experiments". For the uninitiated, this book was THE cookbook for grade school children who wanted to generate chlorine, taste diluted sulfuric acid, make iron sulfide, generate oxygen, burn iron in chlorine gas, generate hydrogen & ignite it and generally run amok throughout the periodic chart. I can't even recall the number of times I drove our entire family outdoors with H2S.

I guess this is the beauty of H2S. It's hard to get poisoned without a mask because the odor is generally intolerable. If it sneaks into you because of partial protection (carbon isn't protection against this gas) you can be on shaky ground.

Some pages back, I noticed someone wondering how we managed to do H2S in the lab. The answer is, with surprising ease. Even in antiquated, deficient fume hoods it wasn't a problem. We had one reaction on our way to dideoxyadenosine where we converted an amide substituted furanose to a thioamide in a 12 L flask filled with ethanol saturated with H2S. Workup started with filtration using 2 L filtering funnels and thus presented a large liquid interface to the atmosphere. Even with crappy hoods (I had OSHA visit them over this very issue...they were quite ruffled...oops...I mean maniacally incensed) we had no issues.

It's funny how effectively familiarity can breed contempt. I don't give toxins a second thought until they are way worse than cyanide or H2S. The scarriest lab toxin to me is bis(chloromethyl)ether (anybody who uses chloroacetyl chloride ought to pay attention). Perfect carcinogen. Easily made anywhere HCL meets HCHO, volatile, perfect "bite" size and window of hydrolytic instability to cross-link your DNA and dangerous at levels that most lab equipment can't even detect. If I recall corectly, a Ni63 detector fitted to a gc was the detector of choice.




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