Date: Fri, 30 Oct 2009 13:30:40 -0400
Reply-To: rphifer**At_Symbol_Here**
Sender: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
From: Russ Phifer <rphifer**At_Symbol_Here**WCENVIRONMENTAL.COM>
Organization: WC Environmental, LLC
Subject: Re: Osmium tetroxide storage, use and disposal
In-Reply-To: <A15AF8D2-5221-4FA3-AB13-0D97E46E5136**At_Symbol_Here**>

Osmium tetroxide is sold pretty much exclusively in sealed vials, either as crystals or in a 4% solution.  It is primarily used as a fixative for electronic microscopy, in solution.  While extremely toxic (by ingestion, inhalation, or skin contact), unused containers should not pose a storage problem as long as they are secured.  Store in a cool, dry, ventilated area.  It should always be used in a hood!  Disposal is interesting, in that it is not theoretically regulated as a hazardous waste (you could look it up!).  The osmium itself is quite valuable and rare (only about 1000 lbs are produced annually, worldwide); it can be recycled to various suppliers and refiners.  However, once used, you need to know which buffers it was used with.  There are six possible buffers for EM use; the two most common are phosphates and cacodylic acid.  The phosphate buffer addition doesn’t make it hazardous, but cacodylic acid is an arsenic compound and the resulting solution would be regulated as D005 EPA waste type.  Many clinical facilities are not aware of this and don’t properly label and describe for disposal.  Check to see which buffers are being used by your EM lab.

Once facility that will accept osmium for recycling is Colonial Metals, in Elkton, MD.  You need a decent quantity, however, to make it amenable for recycling.

Hope this helps….

Russ Phifer

Russ Phifer

WC Environmental, LLC

1085C Andrew Drive

West Chester, PA  19380

610-696-9220x12/ fax 610-344-7519



P Please consider your environmental responsibility before printing this e-mail or any other document

-----Original Message-----
From: DCHAS-L Discussion List [mailto:DCHAS-L**At_Symbol_Here**LIST.UVM.EDU] On Behalf Of List Moderator
Sent: Friday, October 30, 2009 12:02 PM
To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU
Subject: [DCHAS-L] Osmium tetroxide storage, use and disposal

From: "Rengarajan, Kalpana" <krengar**At_Symbol_Here**>

Date: October 30, 2009 11:57:32 AM EDT

Subject: Osmium tetroxide storage, use and disposal

Does anyone have specific guidelines on Osmium tetroxide storage, use 

and disposal. Can you please share?

Thank you


Kalpana Rengarajan, Ph.D., RBP

Assistant Director, Biosafety Officer

Environmental Health and Safety Office

1762 Clifton Road NE, Suite 1200

Atlanta, GA 30322

Phone: (404)727-8863

FAX: (404) 727-9778

You may visit for updated information.


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