Date: Fri, 23 Nov 2007 17:57:57 -0500
Reply-To: List Moderator <ecgrants**At_Symbol_Here**UVM.EDU>
Sender: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
From: List Moderator <ecgrants**At_Symbol_Here**UVM.EDU>
Subject: Re: mercury- final questions
Comments: cc: rpschoon**At_Symbol_Here**

From: 	ahalltoxic**At_Symbol_Here**
Subject: 	Re: [DCHAS-L] mercury- final questions
Date: 	November 23, 2007 12:35:12 PM EST (CA)


I'd suggest that the teacher who has concerns be evaluated by a  
physician who knows about mercury poisoning.  Such physicians would be  
either Occupational/Environmental Medicine Physicians or Medical  
Toxicologists.  To find a Medical Toxicologist in the appropriate  
region, go to and choose "Find a Toxicologist".  We are  
few and far between, but this is the site (all Members are Board- 
Certified Medical Toxicologists).  If this is not an option,  ask the  
evaluating physician to contact your Regional Poison Center (national  
toll-free number 1-800-222-1222 which will automatically switch you to  
the PC in your area/state) for advice on testing and (only if  
appropriate) treatment.  There was a famous case of workers in a  
mercury thermometer manufacturing facility in Vermont dragging home  
significant amounts of mercury on clothes and shoes.  The Vermont  
State Health or Environmental Departments may very well have some good  
advice about testing and clean-up (if needed).

According the manufacturers' website, the Lumex 915 is also known as  
the Zeeman Mercury Analyzer RA-915, and is used to detect mercury  
vapor (one of the more toxic forms of metallic mercury) in air, water,  
natural and stack gases, oil, in solids and sediments, foodstuff, and  
so on.  The method is by atomic absorption spectrometry.  The  
instrument is said to have a detection limit of 2 ng/m3 in air.  (for  
comparison, the ACGIH TLV -- Threshold Limit Value -- for Mercury in  
air is 0.05 mg/m3 Time Weighted Average, Skin Notation although the  
National Research Council's EGLs or AEGLs might be better for  
comparison as they are designed for the general public as opposed to  
healthy workers).  Much more information on this instrument is  
available by either "Googling" Lumex 915 or at 

A very good reference for the evaluating physician:

Yip L, Dart RC, Sullivan JB:  Mercury, in:  Sullivan JB, Krieger GR  
(eds), Clinical Environmental Health and Toxic Exposures, 2nd ed.   
Lippincott Williams & Wilkins, Philadelphia, 2001, pp. 867-879.

Hopefully, this helps.  My daughter teaches high school science on a  
Native American Reservation in Montana and her much neglected  
storeroom has been fun to deal with.

To attempt to answer your questions:

1.  The teacher is correct to have concerns about having inadvertently  
brought some mercury home and mercury is a neurotoxicant that can  
affect young children.

2.  If the mercury exposure was mainly to vapor and he hasn't been in  
the potentially contaminated area for a year or so, blood or 24-hour  
urine testing for mercury might indeed not be elevated at this time.   
Therefore, a "normal" level would not rule out prior exposure, but an  
elevated level certainly would confirm such an exposure.

3.  Yes, I would test the area of the rolling table and the general  
air level in the room.  The Lumex 915 is a direct reading instrument,  
so this should not involve much additional cost.

4.  It makes you the "Bad Guy - Black Hat" in terms of costing the  
school district some money, but it makes you the "Good Guy - White  
Hat" in terms of using your knowledge of science to perhaps correct a  
hazardous work setting for the teachers and, perhaps more important,  
for the students.  Kudos!

5.  As an old US Army Vietnam Era Veteran and a retired United States  
Air Force Reserves Flight Surgeon, I'd do all the CYA you can.   
Anything that disturbs the status quo of the "Powers-that-Be" or costs  
them money (and we all know how schools are underfunded in the best of  
circumstances) can get them upset and looking for someone to blame.  I  
remember very well nearly being deported from Kyrgystan at gunpoint a  
few years back because I told the Minister of Public Health and the  
Minister of Security how their government had messed up dealing with a  
20-ton sodium cyanide spill into a river upstream from 2 villages.

Best wishes and keep up the good work.  Just don't let some "Clinical  
Ecologist" or their ilk anywhere near the potentially exposed folks.   
Much more harm than good from these folks.

Alan H. Hall, M.D.
President and Chief Medical Toxicologist
Toxicology Consulting and Medical Translating Services, Inc.
Laramie, WY
Clinical Assistant Professor of Preventive Medicine and Biometrics
University of Colorado Health Sciences Center
Denver, CO

Telephone:  (307) 745-0600
Cell Phone (preferred):  (307) 399-1564
FAX:  (307) 745-0605
email:  ahalltoxic**At_Symbol_Here**

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