Funny thing happened. Received some chemicals yesterday, and inside the box a 1L container of potassium chromate had broken. The plastic container it was in was very dodgy looking and there was no plastic bag or other protection around it. This had resulted in everything getting a bit, well, yellow. While wearing gloves I removed all the other containers from the box, and cleaned them afterwards from any yellow dust I could see.

 

As some of you may know, potassium chromate is a compound of hexavalent chromium, which is a human carcinogen. During the handling and disposal of the box I could occasionally smell a rather distinct smell which I can only presume was due to the chromate. However I didn't see any visible "puffs" of dust at any point however and the chromate wasn't too finely powdered. I didn't experience any breathing difficulties or throat soreness which might indicate a high exposure. I wasn't in skin contact with the chromate either, and as of yet there are no signs of dermatitis.

 

So, what do you think of an exposure like this? Is a one-time exposure of little significance especially without symptoms?

Chromate or Dichromate?

 

I personaly don`t think there`s any Real cause for alarm there, although why you never did this Outside and with a dust mask on upon finding it in this state beats me!?

I did it outside, and don't own a dust mask. I've been planning to get one (guess that doesn't help now though) and after this I'll indeed get one before handling any stuff like this. And it was chromate, not dichromate.

 

By the way as I haven't completely disposed of the box in the normal sense of the word, how should I? Take it to a specific waste disposal facility? As it's harmful to the environment I don't think it's wise to just dump it in the trash bin. Currently I keep the box (cardboard) in a plastic bag, but IIRC the chromate can corrode organics when wet (formation of chromic acid?).

take it out the bag and just bury it then, it`ll break down quite nicely and safely .

Umm... As in reducing into an oxidation state that doesn't make it a horrid carcinogen?

 

Edit: And not going to the groundwater as hexavalent chromium?

soak it in a Lead nitrate then, it`ll make potassium nitrate and lead Chromate (the same compound used in the yellow lines on roads), then bury it.

No need to worry about your health with this one-time exposure, but next time please be more careful. A very good precaution for dust is to use a towel and bind it around your head (mouth and nose). Not really pleasant, but it works for dust (not for gases).

 

Getting rid of the chromate waste and contaminated material is not that hard. Put it in a bucket (yes, all, the complete cardboard), add water and add some hydrochloric acid and some sulfite. The hexavalent chromium is reduced to trivalent chromium. If it is just a small amount (not more than several grams), then you can flush it down the drain as trivalent chromium. Trivalent chromium hardly is toxic.

Woelen, That`s Boring!

 

the Lead Chromate is Much prettier