[Nhcoll-l] Arsenic testing

[Carrlee, Ellen M (EED)]

I have arsenic tested several hundred speciens (mainly birds) in our collection, mainly using testing papers and using the methods recommended by Cathy Hawks:

http://ellencarrlee.wordpress.com/2009/01/14/arsenic-testing-step-by-step/

This method involves hydrochloric acid, potassium hydroxide, zinc powder, and mercury bromide test papers.

We recently acquired a Bruker Tracer XRF, and I use that now.

However, from what I am seeing from these postings, it looks like maybe folks are not using a methodology with a known negative and a known positive when doing testing?  Every time I set out to do this test, I run a known positive and a known negative to determine if the test is working, my reagents are OK, my equipment is fuctioning, there is not contamination etc.  The XRF has backed up the tests I have done with the test papers.  Also, with any of these methods, you can only say "arsenic not detected".  You cannot really say there is no arsenic.



Best wishes,

Ellen Carrlee

Conservator

Alaska State Museum

________________________________

From: nhcoll-l-bounces at mailman.yale.edu [nhcoll-l-bounces at mailman.yale.edu] on behalf of Lena Hernandez [LHernandez at themosh.org]
Sent: Tuesday, February 25, 2014 5:21 AM
To: nhcoll-l at mailman.yale.edu
Subject: [Nhcoll-l] Arsenic testing


Hi all,

Recently I attempted testing for arsenic in the mounted specimens of our collection. My issues, that I hope some of you can help with, is that I am getting a negative result on specimens that I am sure have arsenic. Has anyone else run into this problem? If so how did you solve it? I am following the protocol developed by NPS in their Conserve-o-Gram 2/3 and using Hach’s arsenic test kit, since the one recommended by NPS is no longer made. Any suggestions would be most welcome. Feel free to contact me off list if you would prefer.


Lena Hernandez
Collections Manager/Registrar

Museum of Science and History
1025 Museum Circle
Jacksonville, FL 32207
(904)396-6674 x212
lhernandez at themosh.org

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