superficial cutaneous stain from chem lab

[zhelfer0306]

After leaving my university chemistry lab yesterday, I noticed a ~1cm yellow stain on the pad of my left thumb. I'm sure it was due to a chemical we were using. After a day of intense washing, it is just as dark as before. The only chemicals that I know came in any contact with my bare hands were a 6M solution of hydrochloric acid (it strangely did not hurt) and some amount of liquid (possibly dehydrated?) potassium ferrocyanide. I'm just worried that I could have some chemical burn or possibly carcinogenic substance exposure going on. There were other chemicals in lab, too, if a full list would be helpful. Any insight would be appreciated. Thanks for the time and feedback.

[Bhupinder Kaur, MD]

Hello,
It can be due to contact dermatitis. Avoid using any lotions and creams for the meantime. Wash the area with a mild cleanser with moisturizing properties like Cetaphil. Then apply a good hypoallergenic moisturizer over the area and see if this improves. If the symptoms still persist then you can apply mild steroid like dermacort and take anti allergic medicine like Benadryl.

If the symptoms persist then get it evaluated from a dermatologist.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.

[zhelfer0306]

It was a lab for credit (with a lecture), not a private research lab, so gloves were not even an option sadly. Any chemical splashes resulted in direct exposure. (which is why I found it strange that such a strongly concentrated HCl wouldn't burn or anything). This is the 5th day of having the stain and it still hasn't even faded a bit.

[Caryopteris]

Did your gloves tear there?