[Histonet] Contaminated Alcohols from VIP processors

[Monfils, Paul]

I have noticed the same thing, and I don't think the cloudiness is due to
xylene.  I believe it is due to water-insoluble substances, particularly
lipids, which have leached out of the tissue samples into the stronger
alcohols. Because these substances are water-insoluble they don't tend to
dissolve in the formalin or the weaker alcohols where a lot of water is
present, but they do dissolve somewhat in the stronger alcohols.  Also,
because they are water-insoluble, they precipitate (become cloudy) when
water is added to the alcohol, as in flushing down the drain. 

Because I'm in a service research lab, I often run one kind of tissue per
processing run, and sometimes only one kind of tissue for several days.  I
have noticed that the degree of cloudiness relates not only to the number of
specimens I have run since the last solvent change, but also very much to
the kind of tissues that were processed.  I can run kidney or lung or
muscle specimens all week and there is minimal cloudiness when I discard the
alcohols.  But if I process a large number of skin or breast or colon or
other fatty samples, the alcohol turns milky white when it hits the water.


> ----------
> From: 	histonet-bounces <@t> lists.utsouthwestern.edu on behalf of
> bamoe <@t> gundluth.org
> Sent: 	Wednesday, March 22, 2006 12:58 PM
> To: 	histonet <@t> lists.utsouthwestern.edu
> Subject: 	[Histonet] Contaminated Alcohols from VIP processors
> 
> 
> 
> 
> 
> Hello all -
> 
> Has anyone had experience with contaminated alcohols coming off a
> Tissue-Tek VIP processor?
> 
> We have two processors - one is a Miles VIP 3000, purchased in 1993, the
> other is a Sakura VIP E300 purchased in 1996.
> We have started experiencing the problem on both machines.
> 
> Our processing schedule utilizes 2 stations each of formalin, 80% ETOH,
> recycled 95% ETOH, absolute ETOH (pure, not reagent grade), xylene, 3 or 4
> paraffin stations, 1 cleaning xylene, 1 cleaning absolute ETOH.
> 
> The formalins and 80% are not contaminated, however the 95% and absolutes
> show cloudiness when flushed with water down the drain. (We are assuming
> that it's xylene causing this, but have not done analysis to confirm.)
> 
> Preventative maintenance was just done last week on both machines (by our
> in-house biomed personnel) and we still have the cloudiness in the 95% and
> absolute alcohols.
> 
> We have ruled out any problems with our recycler and know that the
> alcohols
> are clean when they are put on the processor.
> 
> Any comments would be greatly appreciated!
> 
> Barb Moe
> Gundersen Lutheran Medical Center
> La Crosse WI
> bamoe <@t> gundluth.org
> 
> _______________________________________________
> Histonet mailing list
> Histonet <@t> lists.utsouthwestern.edu
> http://lists.utsouthwestern.edu/mailman/listinfo/histonet
> 
>