As I work with the Chemical Weapons destruction part of the Arsenal, not the production side of the house, I'm forwarding your email to the Industrial Hygienist on that side. She worked with us for many years before moving over there and I have hopes that she might be able to help a little bit.

I'd go ahead and send her email addres s to you, but I lost it and I'm waiting for one of my folks to send it to me so I can forward your email...confused yet?

Don A. Long
CAIH, CEAS I
Southwest Research Institute Laborat ory
Pine Bluff Chemical Agent Disposal Facility
PO Box 20130
White Hall, AR 71612
870-541-4930

From: DCHAS-L Discussion List [mailto:DCHAS-L**At_Symbol_Here**list.uvm.edu] On Behalf Of ACTSNYC**At_Symbol_Here**CS.COM
Sent: Tuesday, August 16, 20 11 8:46 AM
To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU
Subject: [DCHAS-L] CAS #s fo r allotropes of phosphorus

Is anyone out there, or does anyone know, an expert on the allotropes of phosphorus?
 
I'm working on the health effects for the chemicals listed in the next edit ion of the Dictionary of Pyrotechnics--a freebie for a pal I work with on NFPA 1126, the standard of pyro before a proximate audience.

My old Hawleys gives on CAS # 7723-14-0 to all forms and says elemental phosphorus can have allotropes that are "white (or yellow), red, and black."  Other references list a brown allotrope as well.  < br>
Here's the deal. ACGIH has two entries in their big exposure guide booklet:

* White phosphorus CAS# 7723-14-0 which has no TLV, but a DFG MAK 0.05 mg/m 3.

* Yellow phosphorus CAS# 12185-10-3 has a TLV-TWA 0.1 mg/m3; MAK 0.05 and a NIOSH REL of 0.1 mg/m3.

And there's no entry for red phosphorus or any other color.

Pyrotechs use white and red.  And their suppliers as well as other exp erts list the White as CAS 7723-14-0 and Red as 12185-10-3.  And if I googl e various sources I can get different CAS numbers almost at will. They all contradict each other.

Does anyone know if white and yellow are really different allotropes?   Does anyone know which CAS # goes with which?    Specifically is the CAS# 12185-10-3 for yellow or for red?  It's to look like ACGIH might be wrong on this one.

Thanks for thinking on this.

Monona