Thanks for the explanation, and it now makes sense as to what is suspension
and what is a colloidal.  

I was groping obviously for a meaning, or proper discription of lipids in
formalin. 

Gayle Callis 

At 02:38 PM 9/10/02 -0400, you wrote:
>Sorry guys,  just as in the old days when milk came with cream on the top,
>the cream was NOT a colloid when it was separated like that.  The
>'colloidal' WHOLE milk that we drink today consists of a suspension of
>micro-droplets of cream dispersed in a continuous, aqueous protein sol
>(i.e., the milk!).  the cream on top was never a colloid until it was
>dispersed - somewhat permanently.  In order to be a colliid, you must first
>be dispersed in a continuous phase.  Dry Jello is NOT a colloid until it is
>dissolved in hot water, and unless you do something really wrong, the
>dispersion persists until the gel forms.  Add back some heat and the gel
>becomes a sol, again a colloidal dispersion.
>
>I think I have that essentially right.
>
>Fred
>
>> ----------
>> From: 	Vinnie Della Speranza
>> Sent: 	Tuesday, September 10, 2002 2:08 PM
>> To: 	HornHV@archildrens.org; gcallis@montana.edu;
>> histonet@pathology.swmed.edu
>> Subject: 	Re: Interesting point! formalin separation from tissues for
>> disposal
>> 
>> Gayle,
>> You and I are in agreement. I, like you.consider the lipid in the formalin
>> to be a colloid for lack of any better term.it is commonly found floating
>> on the surface of the waste formalin. this is where I'm at now. the Safety
>> people want it (lipid) out but can't offer any advice on how to do just
>> that and of course, I will consider any method that creates additional
>> safety concerns for staff and another full time job to accomplish,
>> undesirable.
>> re: Carrie's suggestion, neutralization followed by drain disposal would
>> not be acceptable at my facility. in fact, this would probably cause me
>> greater headaches as I would have to prove that no formaldehyde remained
>> in the waste before disposal could occur.
>>  
>> I'm hoping someone will have a reasonable suggestion for what has quickly
>> becoming a crisis as they are not allowing me to do any additional
>> disposal of tissues or waste formalin until a solution is found. we don't
>> have the space to permit this stuff to accumulate.
>>  
>> Vinnie
>> 
>> >>> Gayle Callis  09/10/02 11:59AM >>>
>> Vinnie, 
>> 
>> Hazel brings up a good point.  Next question, is what do you do with the
>> separate blood and lipid waste? Has your safety people thought of that?
>> or
>> do you have a way to dispose of these in another manner?  
>> 
>> Maybe looking into formalin recycling would be a good choice, since you
>> have to do so much work to satisfy the safety people.  Then the only waste
>> you have to dispose of is what is left in bottom of recycling unit, small
>> by comparison to volumes of formalin.  Personally, I don't think one can
>> separate lipid out totally, it makes a colloidal solution (hope I am
>> thinking correctly here) and I am sure everyone has seen cloudy formalin
>> from very fatty tissue - and if you can't get it all out, what does your
>> safety people make you do then?? 
>> 
>> Good luck
>> 
>> 
>> At 09:02 AM 9/10/02 -0500, you wrote:
>> >I don't know if I can offer a reasonable solution, but wouldn't these
>> >elements be harmless as they are fixed?   I don't understand their
>> reasoning
>> >for this.   Is the waste company that hauls the spent formalin away
>> >suggesting this?    We have to pour ours off as well.
>> >I sure hope this isn't something that will come my way.    I'll be
>> >interested in replies to this thread.
>> >Hazel
>> >
>> >> -----Original Message-----
>> >> From:    Vinnie Della Speranza [SMTP:dellav@musc.edu]
>> >> Sent:    Tuesday, September 10, 2002 8:43 AM
>> >> To:    histonet@pathology.swmed.edu
>> >> Subject:    formalin separation from tissues for disposal
>> >> 
>> >> I know that this topic has been discussed on the list numerous times
>> >> before however we are being faced with a slightly different slant that
>> I
>> >> would welcome your input on.
>> >>  
>> >> Our Safety dept. has become conerned that our waste formalin contains
>> >> blood and lipid that they feel must be separated from the formalin
>> before
>> >> it can be carted away. 
>> >> We currently use a filtering funnel when pouring off the waste formalin
>> >> but this won't extract the lipid and blood which are in liquid
>> suspension
>> >> in the formalin.
>> >>  
>> >> Has anyone else been required to address this issue? I'm hoping someone
>> >> can offer a reasonable solution that will satisfy our Safety folks.
>> >>  
>> >> thanks
>> >>  
>> >>  
>> >>  
>> >> Vinnie Della Speranza
>> >> Manager for Anatomic Pathology Services
>> >> Medical University of South Carolina
>> >> 165 Ashley Avenue  Suite 309
>> >> Charleston, SC 29425
>> >> Ph: 843-792-6353
>> >> fax: 843-792-8974
>> >
>> >
>> >
>> Gayle Callis
>> MT,HT,HTL(ASCP)
>> Research Histopathology Supervisor
>> Veterinary Molecular Biology - Marsh Lab
>> Montana State University - Bozeman
>> 19th and Lincoln St
>> Bozeman MT 59717-3610
>> 
>> 406 994-6367 (lab with voice mail)
>> 406 994-4303 (FAX)
>> 
>> email: gcallis@montana.edu
>> 
>> 
>> 
>> 
>
>
>
Gayle Callis
MT,HT,HTL(ASCP)
Research Histopathology Supervisor
Veterinary Molecular Biology - Marsh Lab
Montana State University - Bozeman
19th and Lincoln St
Bozeman MT 59717-3610

406 994-6367 (lab with voice mail)
406 994-4303 (FAX)

email: gcallis@montana.edu