<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 15 (filtered medium)"><!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style><![endif]--><style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:Verdana;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p
{mso-style-priority:99;
margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
p.msochpdefault, li.msochpdefault, div.msochpdefault
{mso-style-name:msochpdefault;
mso-style-priority:99;
margin:0cm;
margin-bottom:.0001pt;
font-size:10.0pt;
font-family:"Times New Roman","serif";}
span.emailstyle18
{mso-style-name:emailstyle18;
font-family:"Calibri","sans-serif";
color:#1F497D;}
span.EmailStyle20
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Agree with Dries. How effective a buffer is depends on the buffer, the salt concentrations you are using (which could also has issues around osmotic balances) and what organisms you are preserving. Plus, as recent papers have demonstrated the actual storage vessel can have a significant effect e.g. soda glass versus the superior borosilicate. Ultimately the buffering effect plateaus out which can only be established by good pH monitoring. As previously mentioned by Dries I also think DMDMH / glycerol mix is potentially a viable option here but we do need more data to be confident of this approach.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Regards<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Jules<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=CY style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Prif Gadwraethydd, Gwyddorau Naturiol <o:p></o:p></span></p><p class=MsoNormal><span lang=CY style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Principle Conservator Natural Sciences<o:p></o:p></span></p><p class=MsoNormal><span lang=CY style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="mailto:julian.carter@amgueddfacymru.ac.uk"><span style='color:#0563C1'>julian.carter@amgueddfacymru.ac.uk</span></a><o:p></o:p></span></p><p class=MsoNormal><span lang=CY style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="mailto:julian.carter@museumwales.ac.uk"><span style='color:#0563C1'>julian.carter@museumwales.ac.uk</span></a><o:p></o:p></span></p><p class=MsoNormal><span lang=CY style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>029 20573230<o:p></o:p></span></p><p class=MsoNormal><span lang=CY style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>07870448074</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> nhcoll-l-bounces@mailman.yale.edu [mailto:nhcoll-l-bounces@mailman.yale.edu] <b>On Behalf Of </b>A.J.van_Dam@lumc.nl<br><b>Sent:</b> 03 July 2014 08:26<br><b>To:</b> rw@protectheritage.com; simmons.johne@gmail.com; gregory.watkins-colwell@yale.edu<br><b>Cc:</b> cahaas@vt.edu; nhcoll-l@mailman.yale.edu<br><b>Subject:</b> Re: [Nhcoll-l] long-term storage of amphibian larvae in formalin<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'>Just to add to Rob's comments, of course change of fluid should be decided on pH monitoring, not on the collection example I mentioned where indeed several variables can be of influence (temp./specimen/container/seal/buffer molarity etc.). Still I would recommend when acidity has significantly lowered (more than one pH, coming close to pH 5) to change the fluid.<br><br>Regards,<br><br>Dries.<o:p></o:p></span></p><div><p class=MsoNormal><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'><o:p> </o:p></span></p><div><div><div><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'>Andries J. van Dam, </span><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#FF8000'>conservator</span><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'><br><br>Museum of Anatomy<br>Leiden University Medical Center <br>Building 3 (V3-32)<br>P.O.Box 9600 <br>2300 RC Leiden <br>The Netherlands <br>tel: +31 (0)71 52 68356<br>E-mail: </span><a href="mailto:A.J.van_Dam@lumc.nl"><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif"'>A.J.van_Dam@lumc.nl</span></a><u><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#0000FE'><br></span></u><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'>Visiting address: Hippocratespad 21 </span><span lang=EN-US style='color:black'> </span><span lang=EN-CA style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#FF8000'>Scientific associate</span><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'> Natural History Museum London<br></span><a href="http://www.nhm.ac.uk/" target="_blank"><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif"'>http://www.nhm.ac.uk</span></a><span lang=EN-CA style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#FF8000'>Directory Board member</span><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'> ICOM-CC<br></span><a href="http://www.icom-cc.org/" target="_blank" title="http://www.icom-cc.org/"><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif"'>http://www.icom-cc.org</span></a><u><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'> <br><br></span></u><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#FF8000'>Director</span><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'> Alcomon Company<br></span><a href="http://www.alcomon.com/" target="_blank" title="http://www.alcomon.com/"><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif"'>http://www.alcomon.com</span></a><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'> <span lang=EN-CA><o:p></o:p></span></span></p><div><p class=MsoNormal><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'><o:p> </o:p></span></p></div></div></div></div></div><div><div class=MsoNormal align=center style='text-align:center'><span lang=EN-CA style='color:black'><hr size=2 width="100%" align=center></span></div><div id=divRpF46273><p class=MsoNormal style='margin-bottom:12.0pt'><b><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'>Van:</span></b><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'> Robert Waller [rw@protectheritage.com]<br><b>Verzonden:</b> donderdag 3 juli 2014 9:05<br><b>Aan:</b> Dam, A.J. van (DOO); </span><a href="mailto:simmons.johne@gmail.com"><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>simmons.johne@gmail.com</span></a><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'>; </span><a href="mailto:gregory.watkins-colwell@yale.edu"><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>gregory.watkins-colwell@yale.edu</span></a><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'><br><b>CC:</b> </span><a href="mailto:cahaas@vt.edu"><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>cahaas@vt.edu</span></a><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'>; </span><a href="mailto:nhcoll-l@mailman.yale.edu"><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>nhcoll-l@mailman.yale.edu</span></a><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'><br><b>Onderwerp:</b> RE: [Nhcoll-l] long-term storage of amphibian larvae in formalin</span><span lang=EN-CA style='color:black'><o:p></o:p></span></p></div><div><div><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Just to clarify, formalin is stable with respect to spontaneous decomposition but not stable with respect to oxidation. A buffer system, by definition, will slow but not eliminate drift in pH levels. Different containers and closures will lead to different rates of pH decline. I would hesitate to adopt a fluid change schedule based on a different collection unless that collection uses the same containers and the same buffer formulation.</span><span lang=EN-CA style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Robert Waller</span><span lang=EN-CA style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><span lang=EN-CA style='color:black'><o:p></o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'> </span><a href="mailto:nhcoll-l-bounces@mailman.yale.edu"><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>nhcoll-l-bounces@mailman.yale.edu</span></a><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'> [</span><a href="mailto:nhcoll-l-bounces@mailman.yale.edu"><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>mailto:nhcoll-l-bounces@mailman.yale.edu</span></a><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>] <b>On Behalf Of </b></span><a href="mailto:A.J.van_Dam@lumc.nl"><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>A.J.van_Dam@lumc.nl</span></a><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'><br><b>Sent:</b> July-03-14 6:46 AM<br><b>To:</b> </span><a href="mailto:simmons.johne@gmail.com"><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>simmons.johne@gmail.com</span></a><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>; </span><a href="mailto:gregory.watkins-colwell@yale.edu"><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>gregory.watkins-colwell@yale.edu</span></a><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'><br><b>Cc:</b> </span><a href="mailto:cahaas@vt.edu"><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>cahaas@vt.edu</span></a><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>; </span><a href="mailto:nhcoll-l@mailman.yale.edu"><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>nhcoll-l@mailman.yale.edu</span></a><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'><br><b>Subject:</b> Re: [Nhcoll-l] long-term storage of amphibian larvae in formalin</span><span lang=EN-CA style='color:black'><o:p></o:p></span></p></div></div><p class=MsoNormal><span lang=EN-CA style='color:black'> <o:p></o:p></span></p><div><p class=MsoNormal><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'>Formalin is not stable! We noticed in our fetus collection stored on phosphate buffered formalin (pH 7.3) that after ten years pH is around 6, after 20 years around 5, and after 30 years around 4 (close to unbuffered formalin). Therefore, when using buffered formalin as a preservation fluid, I recommend to change the fluid every 10 years.<br><br>Regards,</span><span lang=EN-CA style='color:black'><o:p></o:p></span></p><div><p class=MsoNormal><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'> </span><span lang=EN-CA style='color:black'><o:p></o:p></span></p><div><div><div><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'>Andries J. van Dam, </span><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#FF8000'>conservator</span><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'><br><br>Museum of Anatomy<br>Leiden University Medical Center <br>Building 3 (V3-32)<br>P.O.Box 9600 <br>2300 RC Leiden <br>The Netherlands <br>tel: +31 (0)71 52 68356<br>E-mail: </span><a href="mailto:A.J.van_Dam@lumc.nl" target="_blank"><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif"'>A.J.van_Dam@lumc.nl</span></a><u><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#0000FE'><br></span></u><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'>Visiting address: Hippocratespad 21 </span><span lang=EN-US style='color:black'> </span><span lang=EN-CA style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#FF8000'>Scientific associate</span><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'> Natural History Museum London<br></span><a href="http://www.nhm.ac.uk/" target="_blank"><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif"'>http://www.nhm.ac.uk</span></a><span lang=EN-CA style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#FF8000'>Directory Board member</span><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'> ICOM-CC<br></span><a href="http://www.icom-cc.org/" target="_blank" title="http://www.icom-cc.org/"><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif"'>http://www.icom-cc.org</span></a><u><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'> <br><br></span></u><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#FF8000'>Director</span><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:black'> Alcomon Company<br></span><a href="http://www.alcomon.com/" target="_blank" title="http://www.alcomon.com/"><span lang=EN-US style='font-size:8.0pt;font-family:"Verdana","sans-serif"'>http://www.alcomon.com</span></a><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'> </span><span lang=EN-CA style='color:black'><o:p></o:p></span></p><div><p class=MsoNormal><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'> </span><span lang=EN-CA style='color:black'><o:p></o:p></span></p></div></div></div></div></div><div><div class=MsoNormal align=center style='text-align:center'><span lang=EN-CA style='color:black'><hr size=2 width="100%" align=center></span></div><div id=divRpF447714><p class=MsoNormal style='margin-bottom:12.0pt'><b><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'>Van:</span></b><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'> </span><a href="mailto:nhcoll-l-bounces@mailman.yale.edu" target="_blank"><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>nhcoll-l-bounces@mailman.yale.edu</span></a><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'> <span lang=EN-CA>[nhcoll-l-bounces@mailman.yale.edu] namens John E Simmons [simmons.johne@gmail.com]<br><b>Verzonden:</b> donderdag 3 juli 2014 5:50<br><b>Aan:</b> Watkins-Colwell, Gregory<br><b>CC:</b> Carola Haas; </span></span><a href="mailto:nhcoll-l@mailman.yale.edu" target="_blank"><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>nhcoll-l@mailman.yale.edu</span></a><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'><br><b>Onderwerp:</b> Re: [Nhcoll-l] long-term storage of amphibian larvae in formalin</span><span lang=EN-CA style='color:black'><o:p></o:p></span></p></div><div><div><p class=MsoNormal><span lang=EN-CA style='color:black'>On Wed, Jul 2, 2014 at 11:36 AM, Watkins-Colwell, Gregory <</span><a href="mailto:gregory.watkins-colwell@yale.edu" target="_blank"><span lang=EN-CA>gregory.watkins-colwell@yale.edu</span></a><span lang=EN-CA style='color:black'>> wrote:<o:p></o:p></span></p><div><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><div><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>...I have, however, found it difficult to maintain the pH properly and even the best of formalin solutions can result in some specimen clearing long-term. </span><span lang=EN-CA style='color:black'><o:p></o:p></span></p></div></div></blockquote><div><p class=MsoNormal><span lang=EN-CA style='color:black'>If buffer the solution with 4 g monohydrated acid sodium phosphate + 6.5 g anhydrous disodium phosphate per liter of one part commercial formaldehyde with nine parts deionized or distilled water, that should be a very stable buffered system. The sources of error that can produce clearing include failure to rinse out field buffers, using tap water to dilute the formaldehyde, and not measuring carefully. You can purchase pre-buffered formaldehyde but personally, I would not trust it for use with scientific specimens. I have never seen clearing when this buffer system is used properly.<o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-CA style='color:black'> <o:p></o:p></span></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><div><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I do not keep reptile eggs in formalin. I fix them in formalin and then transfer them to ethanol. Long-term exposure to formalin can damage the eggshell and cause issues with histology. I treat reptile eggs as I would a whole reptile specimen and transfer them to 70% ethanol for long-term storage.</span><span lang=EN-CA style='color:black'><o:p></o:p></span></p></div></div></blockquote><div><p class=MsoNormal><span lang=EN-CA style='color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span lang=EN-CA style='color:black'>If the formaldehyde is properly buffered, it will not damage reptile eggs. However, I would not bother fixing reptile eggs in formaldehyde unless it is necessary in the field. Better to preserve them directly in 70% ethyl alcohol.<o:p></o:p></span></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><div><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>But, as for amphibian larvae, we’ve started transferring them to 70% ethanol for long-term storage. This also makes them easier to work with from a health and safety perspective, especially with a lot of student workers. </span><span lang=EN-CA style='color:black'><o:p></o:p></span></p></div></div></blockquote><div><p class=MsoNormal><span lang=EN-CA style='color:black'>Because formaldehyde solutions are essentially water ("10% buffered formaldehyde" is really about 96% water), amphibian larvae in 1:9 formaldehyde and water solutions can be safely transferred to deionized or distilled water when people use them, then returned to the buffered formaldehyde for storage. Unless you rinse the specimens very thoroughly when you transfer them to alcohol, you are still going to have trace amounts of formaldehyde in the alcohol solution that can pose a safety issue. Wear neoprene (nitrile) gloves when handling specimens in any case.<o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-CA style='color:black'> <o:p></o:p></span></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><div><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I think that no matter what you do, there will be a cost/benefit. Understand your institutional priorities and weigh those against the rarity of the specimen. This also might be a good reason to photograph examples of each taxon/developmental stage PRIOR to changing storage fluid. Even if you only change to new formalin, you should document. There’s a chance that your formalin isn’t buffered the same way as what was used in the past. That difference can cause some issues with the specimens. So, really, whatever you do there is a risk. </span><span lang=EN-CA style='color:black'><o:p></o:p></span></p></div></div></blockquote><div><p class=MsoNormal><span lang=EN-CA style='color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span lang=EN-CA style='color:black'>I agree with you here, Greg. No solution is perfect for everyone, and documentation of what is done to specimens is critical. However, you can greatly reduce risks to specimens and to workers by controlling which chemicals are used, how they are mixed, and how they are used with a set of enforced SOPs (Standard Operating Procedures).<o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-CA style='color:black'>--John<o:p></o:p></span></p></div></div></div></div></div></div></div></div></div></div></div></div>
<br><P></P>
<P>YMWADIAD<BR>Mae pob neges ebost a anfonir i neu gan Amgueddfa Cymru yn cael ei <BR>sganio gan systemau diogelwch awtomatig er mwyn rheoli negeseuon <BR>digymell a dileu cynnwys amhriodol neu beryglus. Cafodd y neges hon ei <BR>sganio am firysau cyn ei hanfon, ond dylech hefyd fodloni'ch hun bod y <BR>neges, a phob atodiad ynddi, yn rhydd o firysau cyn ei defnyddio gan <BR>nad yw'r Amgueddfa'n derbyn cyfrifoldeb am unrhyw golled neu ddifrod o <BR>ganlyniad i agor y neges neu unrhyw atodiadau. Gall y neges hon ac <BR>unrhyw ffeiliau a atodir ynddi gynnwys gwybodaeth gyfrinachol a <BR>fwriadwyd ar gyfer y derbynnydd yn unig. Os ydych chi wedi derbyn y <BR>neges trwy gamgymeriad, rhowch wybod i ni a chofiwch ddileu'r neges.<BR>Safbwyntiau personol yr awdur yw'r safbwyntiau a fynegir yn y neges <BR>hon, ac nid ydynt o reidrwydd yn cynrychioli safbwyntiau'r Amgueddfa. <BR>Nid yw'r Amgueddfa'n atebol am unrhyw wallau, llygredd neu esgeulustod <BR>a allai godi wrth drosglwyddo'r neges hon, felly na ddibynnwch ar y <BR>cynnwys heb geisio cadarnhad ysgrifenedig yn gyntaf .</P>
<P>DISCLAIMER<BR>Email to and from Amgueddfa Cymru - National Museum Wales is scanned <BR>by automated security systems to control unsolicited messages and <BR>eliminate inappropriate or dangerous content. This message was scanned <BR>for viruses before transmission, but you should also satisfy yourself <BR>that the message, and all attachments, are virus-free before use as <BR>the Museum accepts no responsibility for any loss or damage that might <BR>arise from opening the message or any attachments. This message and <BR>any files transmitted with it may contain confidential information <BR>intended only for the recipient. If you received it by mistake please <BR>inform us and delete the message. The views expressed in this message <BR>are the personal views of the author and may not necessarily represent <BR>those of the Museum. The Museum accepts no liability for any errors, <BR>corruption or omissions that might arise in transmission of this <BR>message, so please do not rely on the contents without seeking<BR>confirmation in writing.</P>
<P></P>
<P>
<HR>
<P></P>
<P><BR>Scanned by iCritical. </P>
<P></P>
<P></P>
<br></body></html>