From: David Roberts <droberts**At_Symbol_Here**DEPAUW.EDU>
Subject: Re: [DCHAS-L] saturated picric acid solution
Date: May 22, 2013 12:03:50 PM EDT
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: <CAN0bzO5fUX=0YD_kwq1r4HVM0Lc36++Kq-=JsJv=R-s5Fvxg-g**At_Symbol_Here**>

I concur. Don't confuse a newer saturated solution of picric acid with old/dried out picric acid from the 60's. With that, the old dried out stuff often had a metal lid - which just made the situation worse.

Biology labs still use picric acid for histology - it's a great staining agent. It does have to be dispose of as hazardous, and you shouldn't blend it with anything as there are reaction possibilities, so just simply lab pack it and any company should take it for a nominal fee.

If you decide to keep it (we have some here), you just need to maintain it. Make sure water stays on top of it, and every now and then invert it to ensure it's still free flowing. I do it about once a year with ours. We only have one bottle, I know exactly where it is, and so we keep track of it, no worries.

Good luck


On 5/22/2013 10:55 AM, Allen Niemi wrote:
I fully agree with Stefan's reply. This would be no big deal and cost about $20.00 for disposal with my usual vendor, including transportation and other fees (as part of a regular pickup). Sure, don't contaminate the solution with metal ions, dry it out, then apply mechanical energy to the resulting dried material.


On Wed, May 22, 2013 at 9:00 AM, Wawzyniecki Jr, Stefan <stefan.w**At_Symbol_Here**> wrote:

Our waste vendor would Lab Pack it. This is not a high hazard item.

-Stefan Wawzyniecki, CIH, CHMM


From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of Ellen M. Sweet
Sent: Wednesday, May 22, 2013 7:29 AM

Subject: Re: [DCHAS-L] saturated picric acid solution


It has to be disposed of as hazardous waste and this is never inexpensive. But, being that it is in solution it'll be cheaper than if it was dried out!

Ellen Sweet
Laboratory Ventilation Specialist
Environmental Health and Safety
Cornell University

From: DCHAS-L Discussion List [dchas-l**At_Symbol_Here**MED.CORNELL.EDU] on behalf of Strode, Kyle [strode**At_Symbol_Here**CARROLL.EDU]
Sent: Tuesday, May 21, 2013 3:10 PM

Subject: [DCHAS-L] saturated picric acid solution

I discovered a bottle of saturated picric acid solution (opened in 1998) in a plastic-capped plastic bottle our chemical inventory. There is about 1-L of the solution left in the bottle. No-one needs it for staining, and I?d like to get rid of it.

It looked like there was some drippage around the neck and cap, so I rinsed it for about 30 minutes under a stream of DI water until all of the material was gone. Then I opened the cap and wiped with a sponge around the cap and rinsed thoroughly with DI water so that there was no apparent presence of material in the vicinity of the cap. After thoroughly cleaning the exterior of the bottle, I recapped it and put it back on the shelf until I can figure out what to do with it.

In the saturated solution form (I believe this means 1.2%), is there an inexpensive and acceptable way to dispose of it?

I have found dramatically conflicting reports of dangers associated with solutions of picric acid in my web searches.


Kyle Strode

Allen Niemi, PhD
Occupational Safety and Health Services
Room 322 Lakeshore Center
Michigan Technological University
Phone: 906-487-2118
Fax: 906-487-3048

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