Potassium Chromate

Meaningful discussion outside of the potato gun realm. Projects, theories, current events. Non-productive discussion will be locked.
User avatar
spuzi14
Specialist
Specialist
Posts: 117
Joined: Sun Nov 06, 2005 9:11 pm
Location: Struthers Ohio

Fri Feb 01, 2008 3:29 pm

I think I came into contact with some Potassium Chromate in chem 2 towards the end of the day. I have like a brown stain on my hands. It's not burning or red but all the MSDS sheets say it's corrosive and all that. Am I alright if nothing is happening?
www.thehurl.org <---Join it!

Those who live by the spudgun, die on the way to the plumbing store <---I don't know.
User avatar
Ragnarok
Captain
Captain
Posts: 5401
Joined: Tue Dec 19, 2006 8:23 am
Location: The UK

Fri Feb 01, 2008 3:35 pm

I would have said this was more for Non Spudgun related, but never mind.

Potassium Dichromate is a bit nasty, it does stain skin very easily. However, if you scrub it properly and all that, you shouldn't come to too much harm.
However, if you do notice any burning or numbness, see a proper doctor about it as soon as possible.
Last edited by Ragnarok on Fri Feb 01, 2008 4:02 pm, edited 1 time in total.
Does that thing kinda look like a big cat to you?
User avatar
spuzi14
Specialist
Specialist
Posts: 117
Joined: Sun Nov 06, 2005 9:11 pm
Location: Struthers Ohio

Fri Feb 01, 2008 3:38 pm

I would have said this was more for Non Spudgun related, but never mind.

I was worried my hands were doomed! But I see your point. I washed my hands about 15 minutes after working with it and have done so at least 4 times since. I was trying to scrub off the stains. Thanks!
www.thehurl.org <---Join it!

Those who live by the spudgun, die on the way to the plumbing store <---I don't know.
User avatar
Ragnarok
Captain
Captain
Posts: 5401
Joined: Tue Dec 19, 2006 8:23 am
Location: The UK

Fri Feb 01, 2008 4:14 pm

I forgot to mention. I made the assumption you were talking about Potassium Dichromate - because it's quite a common mix-up, and it's the stuff more commonly used.
Potassium Chromate is the nastier of the two, IIRC, and I'm pretty sure it's not often used in school labs (at least, by students.)

But whichever it is, there should be no real adverse effects if it's cleaned as best as possible. Long term exposure to either would be a problem though.

In general, try to avoid getting any lab chemicals on your hands (or worse, in your eyes - use goggles!), and if you do get it on your mitts, wash it off - but if teachers are letting you work with it, it's not going to be seriously dangerous. If they see fit to give you a special warning about it, then use gloves, and be triply careful with it, but still - if it's really dangerous, and it has to be used, the teachers will handle it.

I had a weird chemistry teacher - one time he did a lesson's safety briefing in mime.
Does that thing kinda look like a big cat to you?
User avatar
jimmy101
Sergeant Major 2
Sergeant Major 2
United States of America
Posts: 3206
Joined: Wed Mar 28, 2007 9:48 am
Location: Greenwood, Indiana
Has thanked: 6 times
Been thanked: 18 times
Contact:

Fri Feb 01, 2008 4:57 pm

Ragnarok put it pretty well.

The first hazard of something like chromate / dichromate is that they are strong oxidizing agents. That means they will corrode skin and other biological materials. But this is a mass effect, small amout of chromate / dichromate corrodes a small amount of skin and then the process stops since you've consumed the oxidizing power of the oxidizer. Very rough estimate is 1mg Cr<sup>+6</sup> will corrode ~1mg of skin. Not a big deal as long as you are talking about small quantities. Roughly equivalent to a small burn.

When Cr<sup>+6</sup> acts as an oxidizer the result is Cr<sup>+3</sup>. Cr<sup>+3</sup> is much less toxic than Cr<sup>+6</sup>, indeed Cr<sup>+3</sup> is an essential trace element and is considered non-toxic in small amounts.

The second hazard is the long term affect of Cr<sup>+6</sup> compounds. Cr<sup>+6</sup> compounds are both toxic and carcinogenic. This should not really be a problem if the amount you came in contact with was small. Chronic exposure at moderate levels, or a pretty massive one time exposure, can be a problem. You certainly wouldn't want to swallow tablespoon amounts.

In other words, you'll be fine.

Some people think that chemists must have shortened life spans because of their exposure to a wide range of nasty chemical. Actually, chemists tend to live a bit longer than the average person.
Image
User avatar
spuzi14
Specialist
Specialist
Posts: 117
Joined: Sun Nov 06, 2005 9:11 pm
Location: Struthers Ohio

Fri Feb 01, 2008 11:31 pm

You guys were right, I seem to be ok.

Here's what I think happened (how I got it on me)...at the end of class I ended up cleaning up what was left and I simply grabbed a wet paper towel to soak the little tiny specs o' KCrO4 and I think that's when I got it on me. I only got worried and posted this thread when I couldn't wash it off. That brown stain worried me a lot.

I was mainly concerned about getting it in my eyes or blood stream. That's why I was flipping out so badly :( . We have to wear goggles and an apron. We get a zero on the lab if we don't. I try to be as careful as I can but my lab partner is an alcoholic/marijuana smoking muscle man and is dead set on "blowing some stuff up today!!" because he knows I know how to make stuff explode. I didn't choose this partner, he was assigned and I wish it would register that we're mixing solutions...we've got potential but basically there's not enough space in the lab to "blow some stuff up today!"

Looking back, I should have realized I was gonna live after it wasn't burning. Also, I don't think they would really give us anything incredibly harmful. Anyway, thanks for the help...I feel relieved now. Will the brown stains come off soon?
www.thehurl.org <---Join it!

Those who live by the spudgun, die on the way to the plumbing store <---I don't know.
Novacastrian
Staff Sergeant 2
Staff Sergeant 2
Posts: 1603
Joined: Sat Aug 11, 2007 6:59 pm
Been thanked: 1 time

Sat Feb 02, 2008 12:07 am

spuzi14 wrote: Will the brown stains come off soon?
You will have to talk to whoever does your laundry- Oh, you meant the stains on your hands.... :D
User avatar
spuzi14
Specialist
Specialist
Posts: 117
Joined: Sun Nov 06, 2005 9:11 pm
Location: Struthers Ohio

Sat Feb 02, 2008 12:48 am

I might have seen that coming. :lol:
www.thehurl.org <---Join it!

Those who live by the spudgun, die on the way to the plumbing store <---I don't know.
Post Reply