[NHCOLL-L:400] Re: (no subject)

[Steve Halford]

Was it all the jars this happened in, or just the ones that had contained
formalin?

I had this happen to me a couple of times when transferring our invert
collection from 10% formalin to 70% EtOH.  I assumed it was
paraformaldehyde formation.  It didn't happen frequently enough (twice in
1000+ specimens) to be a problem or to see any particular cause -- I just
tipped out the cloudy alcohol and replaced it. If you're really concerned
about wasting EtOH you *could* try filtering it, but really you should be
thinking about 2-3 changes of alcohol to flush out the formalin anyway.

BTW, wouldn't it be simpler to make up carboys of 70% EtOH and do the
transfer in a single operation? 
HTH

Steve (halford at sfu.ca)
Museum Technician
Simon Fraser University
Burnaby, B.C., Canada



On 19 Jan 2000 agignac at canada.com wrote:

> I am currently working on the herpetology collection at
> the University of Victoria.  I have been changing the 
> fluid in already-preserved specimens, and have 
> recently run into a problem.   
>               
> For the last several weeks I have been emptying the 
> old fluid (either 40% EtOH, or 10% formalin), 
> then adding 95% EtOH, and diluting with distilled 
> water to make 70% EtOH.  On Monday, however, I had to
> leave the specimens in the jars 3/4 full with 95% EtOH,
> and then add the water to dilute today (Wednesday).  
> On adding the water, the entire solution turned 
> extremely milky.  It seems that the only way to remedy
> this is to replace the EtOH and start again, but I am 
> reluctant to do that for the cost.   
>               
> Has this been encountered before, and if so, does 
> anybody know why?  I assume it has something to do 
> with the stronger EtOH leaching something out of the 
> specimens, but am unsure what this would be.  Does 
> anybody know anything that can be done aside from 
> replacing the EtOH? 
>               
> Advice would be very welcome in the next couple of 
> days, after that I'll have to be finished the job.  
> However, any other examples or explanations would be 
> welcome at any time.   
>               
> Thank you for your time, 
>               
> Angie Gignac
> Herpetology Lab 
> Department of Biology 
> University of Victoria 
> (250) 721-7103 
> agignac at canada.com 
> 
> 
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