what happens with frequent exposure to methanol?

[alexi_x3]

i have a part-time job at a lab where i have to clean glassware with methanol. i work with it for about 3 hours a day, 2-3 days a week. i do wear gloves, goggles, and a lab coat but oftentimes it splashes onto my skin. i also feel like i inhale a good amount of it. is this much exposure dangerous to my health?

[crazybrain68]

I would think as long as you don't actually drink the methanol you should probably be fine. If you do drink it, it will blind you if it doesnt kill you.

[hermanntrude]

if you use it that frequently, you should have read the MSDS which would explain the hazards involved.

[GDG]

According to the Merck Index (12th ed., 1996):

Poisoning may occur from ingestion, inhalation or percutaneous absorption. Acute Effects: Headache, fatigue, nausea, visual impairment or complete blindness (may be pemanent), acidosis, convulsions, mydriasis, circulatory collapse, respiratory failure, death. Death from ingestion of less than 30 ml has been reported. Usual fatal dose 100-250 ml. Chronic: visual impairment.

 

See also Wikipedia on Methanol toxicity.

 

Try to avoid breathing it: I would do all handling in a fume hood, to the extent possible.

[Justonium]

Do not touch methanol, ever, and make sure you are in a well ventilated area! Methanol is very poisonous and small amounts can lead to blindness!

[jdurg]

Do not touch methanol, ever, and make sure you are in a well ventilated area! Methanol is very poisonous and small amounts can lead to blindness!

 

Okay, you're blowing things a bit out of proportion here. Internally, CH3OH is very nasty as your liver metabolizes the methanol into formaldehyde in the same manner that it converts ethanol into acetaldehyde. However, CH3OH that you spill on your skin will not be absorbed at nearly the same rate into your bloodstream as it will if you drink it, and even then the amount that gets absorbed into your bloodstream is going to be miniscule. Not enough to damage you.

 

When you drink a fermented beverage, you drink small amounts of methanol. The fermentation process doesn't produce only ethanol. A small amount of methanol and other alcohols are produced too. If methanol was as toxic as you make it out to be, then drinking one hard-liquor based beverage would blind you.

 

So yes, methanol is a dangerous substance but it is not nearly as bad as you have made it out to be. We appreciate your willingness to help out others and make them aware of a danger, but your post was akin to screaming out that the building is on fire when someone had just lit a candle in the living room.

[Justonium]

Oh, sorry if I've made a mountain out of a particularly large mole hill, but I read the MSDS and it said all these things. I guess they just have to tell the maximum amount of precautions that they can for legal reasons. You probably know more about methanol though, and if you're saying it's ok to touch, I'll take your word for it.

[UC]

Oh, sorry if I've made a mountain out of a particularly large mole hill, but I read the MSDS and it said all these things. I guess they just have to tell the maximum amount of precautions that they can for legal reasons. You probably know more about methanol though, and if you're saying it's ok to touch, I'll take your word for it.

 

MSDS are generally severely blown out of proportion for legal reasons, as you said. For example, read this one about table salt:

 

http://www.jtbaker.com/msds/englishhtml/s3338.htm

 

It suggests goggles, gloves, and having an eyewash station nearby when handling it.

[jdurg]

Oh, sorry if I've made a mountain out of a particularly large mole hill, but I read the MSDS and it said all these things. I guess they just have to tell the maximum amount of precautions that they can for legal reasons. You probably know more about methanol though, and if you're saying it's ok to touch, I'll take your word for it.

 

Exactly. We like to have participation in the forums and appreciate your input, we just don't want to blow things way out of proportion. The MSDS sheets will state what "COULD" happen, but they don't state the likelyhood of that occurence happening. If one was to follow all of the guidelines of the MSDS sheets to a tee, then yes, you wouldn't have any unexpected incidents ever. But the amount of money and time spent adhering to those guidelines would be quite consuming.

[CaptainPanic]

MSDS are generally severely blown out of proportion for legal reasons, as you said. For example, read this one about table salt:

 

http://www.jtbaker.com/msds/englishhtml/s3338.htm

It suggests goggles, gloves, and having an eyewash station nearby when handling it.

That makes sense for salt:

Goggles are standard in a lab. Salt will eventually dry your skin: therefore gloves are needed. Perhaps not if you are making an omelet, but if you work with salt for 8 hrs/day, I really suggest gloves... And if you ever had any sweat in your eyes, you know you want to be able to wash your eyes. If an eyewash station is suggested, and you work with salt, you might also read that as: have the possibility to wash your eyes at a toilet. "Eyewash station" is simply the over-powered emergency version of the toilet sink.

 

However, it does not suggest use of a fume hood because table salt does not evaporate at all... MSDS suggest all safety precautions that might make sense, but will never suggest anything useless.

 

Therefore, reading a MSDS will give you an insight into all the possible dangers, and the effects that these can have on you and others around you.

 

Regarding methanol:

Search for the TLV value (Threshold limit value)

See whether the TLV value for 15 minutes, or for 8 hrs will be applicable (you have to decide that for your own safety)

Then check the vapor pressure of methanol at room temperature.

Do a simple calculation to turn the vapor pressure into a concentration, and compare it to the TLV value.

 

If the TLV value is significantly lower than the vapor pressure, it's best to work with methanol in a well ventilated room, or better: in a fume hood.

 

If methanol enters the body through the skin, this will be specifically mentioned in the MSDS.

 

If you splash the methanol on your hands, you can do 2 things:

- wear gloves

- or better: change your equipment so that it doesn't splash anymore!

Edited May 29, 2009 by Mokele
Switching from dutch to US term at user's request.

[CaptainPanic]

I believe it is your right as a worker that you should raise the issue with your boss and management in order to request for either a fumehood or a room with better ventilation. As an employer they should provide you with such facilities.

 

I think it's your right as a worker to have it investigated, and if the conclusion is that you need more protection, then it's your right to get more protection (as defined by rules and regulations)..

 

It's the right of your employer to refuse additional protection if there is limited risk (as defined by rules and regulations).