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Author: Subject: H2S intoxication
kmno4
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[*] posted on 11-5-2008 at 11:38


I work in a factory, where is H2S in industrially produced and I saw only one case of H2S poisoning. It was caused by leaking sluice valve and man standing close to it took a deep breath.
He made few steps (propably he wanted to run) and fell down, loosing consciousness.
Fortunately, after ~10 seconds he awoke, got up... and it is all story. The most scaring thing for me were his eyes opened during
those 10 seconds ( I was holding his head and screaming his name, heh). People are afraid of HCN, but often forget that H2S has the same "power".
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[*] posted on 11-5-2008 at 12:45


This is a fairly good description of what H2S does and does not do (be aware, this details brain damage in a Rhesus monkey resulting from non-lethal exposure, which is kinda scary: the article - http://www.euro.who.int/document/aiq/6_6hydrogensulfide.pdf):

Quote:
Effects on humans
In its acute form, hydrogen sulfide intoxication is mainly the result of action on the nervous system. At concentrations of 15 mg/m3 and above, hydrogen sulfide causes conjunctival irritation, because sulfide and hydrogen sulfide anions are strong bases (11). Hydrogen sulfide affects the sensory nerves in the conjunctivae, so that pain is diminished rapidly and the tissue damage is greater (11). Serious eye damage is caused by a concentration of 70 mg/m3. At higher concentrations (above 225 mg/m3, or 150 ppm), hydrogen sulfide has a
paralysing effect on the olfactory perception (2), so that the odour can no longer be recognized as a warning signal. At higher concentrations, respiratory irritation is the predominant symptom, and at a concentration of around 400 mg/m3 there is a risk of pulmonary oedema. At even higher concentrations there is strong stimulation of the central nervous system (CNS) (2), with hyperpnoea leading to apnoea, convulsions, unconsciousness, and death. At concentrations of over 1400 mg/m3 there is immediate collapse. In fatal human intoxication cases, brain oedema, degeneration and necrosis of the cerebral cortex and the basal ganglia have been observed (11).

If respiration can be maintained, the prognosis in a case of acute hydrogen sulfide intoxication, even a severe one, is fairly good. There are reports of neurasthenic symptoms after severe acute intoxication, such as amnesia, fatigue, dizziness, headache, irritability, and lack of initiative (11). A decrease of delta-aminolaevulinic acid dehydrase (ALAD) synthase and haem synthase activity in reticulocytes one week after hydrogen sulfide intoxication has been reported (12), together with low levels of erythrocyte protoporphyrin. The ALAD and haem synthase activities returned to normal two months after the accident, erythrocyte protoporphyrin remaining low. Changes in the electrocardiogram have been reported after acute hydrogen sulfide intoxication, these changes being reversible (11). No tolerance to the acute effects of hydrogen sulfide has been reported to develop (11). The mortality in acute hydrogen sulfide intoxications seems to be lower than that reported in 1977; according to a recent Canadian report it is now 2.8% (13), whereas formerly it was 6% (2). This may be a result of improved first-aid procedures and increased awareness of the dangers of hydrogen sulfide.

Information about longer-term exposures to hydrogen sulfide is scanty. Eighty-one Finnish pulp mill workers who were exposed to hydrogen sulfide concentrations of less than 30 mg/m3 (20 ppm) and to methyl mercaptan concentrations of less than 29.6 mg/m3 (15 ppm), displayed loss of concentration capacity and chronic or recurrent headache more often than a nonexposed control group of 81 workers. Restlessness and lack of vigour also appeared more often, but the findings were not statistically significant. There was also a tendency towards more frequent sick leave among the exposed group (6). One report cites decreased activity of haem synthesizing enzymes in reticulocytes of pulp mill workers exposed for years to organic and inorganic sulfides, with hydrogen sulfide concentrations of between 0.075 mg/m3 and 7.8 mg/m3 (12). No information is available as to whether the observed effect was related to peak concentrations or average concentrations. It can, however, be assumed that average exposure was considerably higher than 0.075 mg/m3 (around 1.5-3 mg/m3). Furthermore, there is no firm proof that hydrogen sulfide was the causative agent, as there may be confounding factors (other substances).

Epidemiological data concerning longer-term exposures are limited. Seventy per cent of workers exposed to hydrogen sulfide daily, often at 30 mg/m3 or more, complained of such symptoms as fatigue, somnolence, headache, irritability, poor memory, anxiety, dizziness, and eye irritation (14). In a Finnish mortality study workers in a sulfate pulp mill showed excess mortality from cardiovascular diseases (standardized mortality rate 140), and especially from heart infarction (standardized mortality rate 142). The findings were statistically significant. In the same study population, cancer incidence was not significantly different from, that of the general Finnish population (15).


Brain oedema and increased risk of heart/lung condition(s) appear to be the more disturbing long-term effects, while pulmonary oedema in the short-medium term would suggest that a visit to the doctor is mandatory. The good news is the lack of increase in risk of cancer(s) (which is associated with both phosgene and mustards).

What about a strong ammonia solution as the scrubber?




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[*] posted on 11-5-2008 at 14:17


I think there was a certain numbing effect, as today I have a slight chest pain and irrated sinus, that i didn't feel yesterday.
Also, the symptoms during lest night seem to correspond pretty well to Paroxysmal nocturnal dyspnea, so I am definatively going to see a doctor tomorow, even though apparently nothing much can be done to cure it. I will try to use a extra pillow or two and see if it helps or not..

Well keep you guys updated with the doctor's advise.... Hope I will be able to get some sleep tonight.




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[*] posted on 11-5-2008 at 22:00


Quote:
Originally posted by Klute
Also, the symptoms during lest night seem to correspond pretty well to Paroxysmal nocturnal dyspnea


This sounds similar to 'Cheyne-Stokes' breathing which affects people at high altitude. Sometimes people wake up with a feeling of suffocation.

According to 'Medicine for Mountaineering', 4th ed, Wilkerson ed:

Quote:

Acetazolamide (159- I think this is 'Diamox' http://en.wikipedia.org/wiki/Acetazolamide ) relieves the periodic breathing seen at altitude. Sedatives are harmful in such situations and should be avoided. An aminophylline rectal suppository at bedtime may help if respiratory irregularity prevents adequate rest.


I wonder if Diamox would help? (Does sound better than the last bit.) Hope you are ok..
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[*] posted on 12-5-2008 at 00:36


Ooooohh... Yeah, those suppositories are always so much fun! :( I have gone to sleep before after taking 50-75mg of diphenhydramine HCl and have woken up because I stopped breathing. It's a terrible sensation to wake up and feel like you've been underwater for a few minutes and then have to catch your breath. I would have to say definitely avoid depressants. Especially alcohol and opiates!



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[*] posted on 12-5-2008 at 05:50


I have a medical treatment that must worsen things. This night wasn't as bad as last night, but i still woke up several times with the impression my heart had stop beating and I was not far from passing out. Sitting upright and walkign a bit made things better, I used sevral pillows and slept with a 45° angle, which must had improved things as I didn't wake afterwards.
No coughing up though, and the chest pains have disappeared, so I guess things are improving. I completly forgot this is a non-working day in France, so my doctor isn't working, I will wait for tomorow to go there.




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[*] posted on 12-5-2008 at 12:13


Yeah, that was the absolute worst part for me. I couldn't sleep for weeks because I kept waking up and finding that I stopped breathing :( Sleeping with a whole bunch of pillows so that you're almost sitting up helps.



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[*] posted on 12-5-2008 at 12:28


Klute, do you mean your heat skips a beat? Mine does that every now and then and it always scares the shit out of me. Just 2 days ago I was eating at a restuarant and my heart stopping beating for what felt like a 3 seconds or so. I almost passed out just from being so startled.

My heart skips a beat maybe twice a week. Does anyone else get that sensation that often?




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[*] posted on 12-5-2008 at 12:47


Funny you mention that, I used to have that problem a while back, at one point i couldn't go to sleep correctly because of it and suffered from pretty severe sleep deprivation... it haunted me.. and i was so scared of it happening again i would look out for it and never be able to peacefully dozz off...

It stops roughly at the same time i stopped smoking (i was smoking nearly 2 packs a day, and maanged to stop one day and never started since), and haven't been bothered with it since, so i simply considered it to come from smoking.

What i felt these two last nights was similar, but much more alarming, it "felt" more dangerous. I'll tell the doctor of the previous beat disorders, maybe it could be connected, like having an undergoing problem that has been re-awaken by the exposition.
Smoking possibly worsened things in the past, and when i stopped things went better to the point were it didn't disturb me anymore, the gas possibly did the same thing that cigaret smoke did but in a much shorten period.




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[*] posted on 13-5-2008 at 02:56


Quote:
Originally posted by MagicJigPipe
Ooooohh... Yeah, those suppositories are always so much fun! :(


Don't like it? Shove it up your arse:D




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[*] posted on 13-5-2008 at 08:53


That has to be it. I smoke a little less than a pack a day (lights, every 24hrs) and have been smoking for about 3 years. At one point I got up to two packs a day (full flavor) while I was delivering pizzas (I chain smoke while driving). I'm actually taking it slow and smoking 1 less cigarette per week. I started out at 20 a few weeks ago (1 pack) and now I'm at 17.

I could have sworn I got this sensation before I started smoking, though. It just didn't scare me as much until a bad episode I had with a certain drug about 3.5 years ago.

I think you're right about the cigarette smoke doing basically the same thing over a longer period of time. And certainly cigarette smoke contains some H2S.




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[*] posted on 14-5-2008 at 05:01


This maybe slightly OT, or possibly even getting us back on topic, depending on how you look at it.

Rats. I have them living under a shed in my garden but because the little b*stards only come out at night it's tricky to take the air rifle to them. And because the shed was build on concrete and sand it's not exactly practical to lift or move it, yet they're under there as I can see gnawed holes in the sides and stuff.

Anyway..I was thinking about an easy way to get rid of them and I thought 'gas them'. OK...so which gas? It would have to be toxic, easy and cheap to produce and heavier than air so that it would sink into the foundations and rat holes. So my first thought was Chorine. But then I thought 'nope, that's a WW1 chemical weapon...plus the fact that it makes strong acids when exposed to water which are not the kind of thing you want eating away at your foundations'. Then I considered CO<sub>2</sub> (probably not toxic enough), NH<sub>3</sub> (lighter than air and would float away), SO<sub>2</sub> (produces strong acids with water)...none of them were suitable for reasons provided. So then I thought H<sub>2</sub>S - easy to make, toxic and heavier than air.

What do you think? Make some FeS and pop it in a bowl or container of some kind. Place this container(s) into one (or more) of the hole as far in / down as I can, and then pour some dilute acid onto it. Place a bit of wood over the hole for added cover and then leave the gas to sink down into the rat den. Because of the stink, any other animals (like cats) should leave it well alone and the rats should all die. Or they run out and I'm waiting with my air rifle.

Appreciate any comments

Thanks


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[*] posted on 14-5-2008 at 10:04


Why not use rat poison? It effective, selective, and it's not going to kill you unless you eat it (in which case...).

H2S isn't controlable, and will kill much more than rats. Imagine your little sister comming to play around while you realize the wind just died down and you smell rotten eggs.. ARe you going to inject here some sodium nitrite? Plus it reacts with water leaving toxic/basic sulfides. Just avoid the stuff IMHO.

I did a reaction with it because the target compound can't easily be obtained by other means. I would not do a reaction with it if i had other means to do so, and I will certainly not use it to kill rats while a whole bunch of stuff can kill them. Damn even alkali cyanides would be safer IMHO.

[Edited on 14-5-2008 by Klute]




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[*] posted on 14-5-2008 at 10:27


I tried to get a racoon out from underneath my house (crawlspace, I have a wooden foundation suspended above the ground) at one point by "gassing" it with a small bucket of heated, household ammonia. For some reason it does not seem to affect animals the same way. It was pretty uncomfortable to stay in there.

By the way, joedick, thanks for cluttering up and hijacking the thread with your random comments. Try using the edit feature next time. Triple posting is frowned upon.

[Edited on 5-14-2008 by MagicJigPipe]




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[*] posted on 14-5-2008 at 13:23


Quote:
Originally posted by MagicJigPipe
I tried to get a racoon out from underneath my house (crawlspace, I have a wooden foundation suspended above the ground) at one point by "gassing" it with NH3. For some reason it does not seem to affect animals the same way. Even though just walking within a few feet of the entrance caused me to recoil in horror while my nose and eyes leaked like crazy, the damn thing didn't come running out. Eventually it got so concentrated that I thought I was going to kill it (or get the police called on me. To the average person in my area any chemical smell means METH).

I thought for sure that the horrible sensation would cause the damn thing to run out as quickly as possible. My guess is that it's natural reaction is to run away from what appears to be the source of the chemical so it might have just huddled in a corner, scared shitless. Maybe it thought it would only get worse if it went towards the door... I don't know...


And we wonder why chemistry as a hobby is frowned upon.

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[*] posted on 14-5-2008 at 15:15


Quote:
Originally posted by MagicJigPipe
What are you, one of those crazy PETA people? What's the difference between what I did and what AngleEyes is trying to do except for not trying to kill the animal? You may like rats, racoons and other annoying animals inhabiting your dwelling but I don't. What does it matter how I get rid of it? Would you rather I shot and killed it? Oh, yeah, that would have been better, just kill it, right?

All you ever do on this forum is talk about legal issues and shit. Where's all your interest in chemistry that makes you so worried? I can't believe you would have the nerve to come to this thread and say some bullshit like that out of nowhere. Why don't you try contributing to some chemistry discussions for a change?

Stop talking out of your ass like you always do and FOD.

[Edited on 5-14-2008 by MagicJigPipe]


I think you should takes Klute's advice. I could care less what you think about me.

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[*] posted on 14-5-2008 at 15:29


Quote:
Originally posted by MagicJigPipe
Klute didn't give me any advice. Nor did he give any advice to anyone that has anything to do with me. That being said, what the hell are you talking about?

Once again, talking out of your ass.

If you delete your posts I will delete mine. Next time you should keep your presumptive and instigative comments to yourself.


I see no reason to delete my posts.

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[*] posted on 14-5-2008 at 16:24


Well, there goes another interesting thread...

But, before then, I am glad to hear your OK, Klute. The skipped heartbeats are likely premature ventricular contractions (PVCs, jokes aside). The electrical signals in the heart become borked and the heart "resets". The result is a skipped beat followed by a really hard one (almost a s freaky as the skipped beat).

I quit smoking (after 19 yr) one year ago and they have decreased, but not gone away. I was "clocked" (with a Holter monitor) at 1300+ PVCs/d!

Anoxia is a major cause (of PVCs) and cigarette smoke actually contains a fair amount of HCN (which causes anoxia). This was manifest by my red-cell count being much higher than normal despite living at or below sea level. It seems to me that The H2S can could a similar situation (only the dose was larger so the effect is more pronounced).

If it is, indeed like this (and the common antidote suggests this) it should improve over time.

Cheers,

O3

[Edited on 14-5-2008 by Ozone]




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[*] posted on 14-5-2008 at 18:20


I work in an industrial setting where H2S is generated often. Even with all the safeguards like wall mounted monitors, its possible to get a whiff that will start to deaden the sense of smell. I have experienced the change in odor from "rotten egg" to "sickeningly sweet" which presumably occur before total loss of smell and finally unconsciousness.

We have pager sized H2S monitors that vibrate/flash/beep when exposed to 10ppm H2S. These units can be bought for a few hundred dollars, and if you must play with H2S they are worth it. It's important to remember that humans can detect H2S odor in parts per billion when the toxicity range is in the parts per million. Humans probably developed this trait through natural selection - those who were not averse to the odor of H2S likely died off long ago.

The company's policy for dealing with gas is to carry the personal detectors and have a gas mask on hand for escape only when the detector goes off. The gas masks are the full face type with a carbon style filter, about the size of a large Spam can. For people who must work in the gas - operations crew going back in to close valves etc, must wear full SCBA dress and work in pairs.

Anyways, H2S can be scary stuff to work with even if you have all the necessary supplies to mange the risk.
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[*] posted on 14-5-2008 at 19:01


Quote:

The result is a skipped beat followed by a really hard one (almost a s freaky as the skipped beat).


I know exactly what you mean here. I became subject to arythmia when I was 36 years old. I quit an overly stressful job and it greatly subsided. I have lived with it for decades. I usually get it now only when overstressed by physical exertion, too much caffeine, or not enough sleep. I understand that some forms of arythmia can kill you.

Quote:

Anyways, H2S can be scary stuff to work with even if you have all the necessary supplies to mange the risk.


What amazes me is that I remember H2S being available from a valved supply hose in a hood when I took general chemistry in college (1960's). What if some clueless freshman had just left that valve open? I don't remember any safeguards, or warnings from the instructor. Now, I believe that for the qualitative analysis tests sulfide is generated in situ using a small amount of thioacetamide.

Klute, I'm glad to hear that you are feeling better and wish you a full recovery. I have played with H2S in my home fume hood. I certainly will think long and hard before doing that again.

[Edited on 14-5-2008 by Magpie]
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[*] posted on 14-5-2008 at 22:26


Thank you all for your concern! I am feeling much better, although i still havea little breathing disconfort, and I pay much more attention to my heartbeat. Curiously, i seem to notice these skips in the evening/night rather than during the day. I guess I'm too busy/occupied at daytime to notice. I still haven't been able to see my doctor, but will do so tomorow.

Magpie, how well did your fume hood handle the gas? Did you get any smell? How much gas was generated/handled? It would be interesting to see how well a good (I insist, a good, as yours :) ) fume hood can handle H2S, as the reference I inspired myself simply states that copious amounts of H2S and H2 are liberated. They simply continu and extract three times with ether. I know publications rarely state the safety conditions or precautions needed, and rely on the readers training/logic sense to do the reactions: ie publications suing BuLi won't advise you do not add water to it or take a sip out of it :). But i suppose they must have worked in conventional conditions, under a good hood with the sash well down, as i can't imagine how else they could have extracted and handled the extracts and the sludge without been exposed.

I'm setting plans for my fume hood, and hopefully will start building it in a month or two when things calm down at work.




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[*] posted on 15-5-2008 at 10:29


Klute, I generated the H2S for the purpose of making CdS. See this thread:

http://sciencemadness.org/talk/viewthread.php?tid=4676&p...

One of the problems with H2S is that even though we know it is deadly we tend to get careless due to familiarity. I used it in several chemistry classes. At one place I worked they had a tertiary waste treatment process using a rotating biosurface. It was housed in a building with strong forced ventilation. When you walked in the building you could smell the H2S. In fact it could be smelled throughout the surrounding residential neigborhood! This was a public relations problem, and the odor was eventuatally eliminated by adding ppm levels of FeCl3 to the waste stream.

At times I have contemplated making a small amount of KF and KCN. Probababy due to unfamiliarity I fear them more than H2S.
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[*] posted on 15-5-2008 at 10:40


Why do you fear KF? Apparently, it is no more toxic than KBr and not much more than KI. Are you afraid of it's hygroscopy that forms semi-corrosive solutions?

[Edited on 5-15-2008 by MagicJigPipe]




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[*] posted on 15-5-2008 at 10:51


How well do the symptoms in the original poster's experience tally with a panic attack. Here's a description from wiki.
"Descriptions
Many who suffer panic attacks state they are the most frightening experiences of their lives. Sufferers of panic attacks report a fear or sense of dying, "going crazy", and/or experiencing a heart attack, feeling faint, nauseous, "flashing vision", or losing control of themselves. These feelings may provoke a strong urge to escape or flee the place where the attack began (a consequence of the sympathetic "fight or flight" response).

A panic attack is a response of the sympathetic nervous system (SNS). The most common symptoms may include trembling, dyspnea (shortness of breath), heart palpitations, chest pain (or chest tightness), hot flashes, cold flashes, burning sensations (particularly in the facial or neck area), sweating, nausea, dizziness (or slight vertigo), light-headedness, hyperventilation, paresthesias (tingling sensations), sensations of choking or smothering or derealization, or the feeling that nothing is real. These physical symptoms are interpreted with alarm in people prone to panic attacks. This results in increased anxiety, and forms a positive feedback loop.[4]
"

And how well do they tally with the observation made about someone who was affected by H2S?

"I saw only one case of H2S poisoning. It was caused by leaking sluice valve and man standing close to it took a deep breath.
He made few steps (propably he wanted to run) and fell down, loosing consciousness.
Fortunately, after ~10 seconds he awoke, got up... and it is all story. "
(from earlier in this thread)

I'm not certain this post is about a case of H2S poisoning.


[Edited on 15-5-08 by unionised]
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MagicJigPipe
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[*] posted on 15-5-2008 at 10:54


That has certainly happened to me after I thought I had been overexposed to something. However, the symptoms of the "panic attack" disappear within an hour. His symptoms did not.



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