We rinse according to size of the bone, A bone biopsy will not take long,
maybe 15 minutes or so, larger bones anywhere from 30 min to a few hours.
Long rinsing can swell tissues (overnight). RDO contains a high HCl
concentration. One of bad things about not rinsing is the first stations in
processing cycle are contaminated with decalcifier, altering pH. If you run
a huge number of RDO decalcified samples, this could be a problem. HCL +
formalin will form a toxic, carcingenic compound (Carson, JOH publication).
I know people who simply rinsed a needle biopsy off with tap water and some
don't bother, just put in processor without problems. CAL-X is a formic
acid solution and is compatible with formalin.
I am a proponent of rinsing and do so for all decalcifying solutions based
on size of bone.
Gayle M. Callis
Bozeman MT 59715
----- Original Message -----
From: "Rena Fail"
To: "'Fischer, R. B'" ;
Sent: Tuesday, May 06, 2008 11:37 AM
Subject: RE: [Histonet] RINSING IN TAP WATER AFTER DECAL
> The rinse step is necessary between formalin and RDO, the two chemicals
> should not be combined
> -----Original Message-----
> From: email@example.com
> [mailto:firstname.lastname@example.org] On Behalf Of Fischer,
> R. B
> Sent: Tuesday, May 06, 2008 12:22 PM
> To: email@example.com
> Cc: Delcambre, Linda V
> Subject: [Histonet] RINSING IN TAP WATER AFTER DECAL
> We have been using "RDO" and "CAL-X" decal solutions for some time now.
> After the specified times in the decal solutions, the specimens are
> rinsed in running tap water for about 10 minutes before being placed
> back in 10%NBF for routine processing. We were rinsing to get rid of the
> nitric acid. My questions are (1) Is this rinse step necessary? If it
> is, (2) How long is an adequate time for rinsing?(3) How are other labs
> handling the specimen post decal, and before processing?
> R.Brian Fischer
> Histology Lead Tech
> Community Hospital of the Monterey Peninsula
> PO Box HH Monterey Ca. 93942
> Fax: 831-6583683
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