Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uunet!aecom!werner
From: werner@aecom.yu.edu (Craig Werner)
Newsgroups: sci.bio
Subject: Re: The pH of saliva
Message-ID: <2635@aecom.yu.edu>
Date: 30 Nov 89 04:34:39 GMT
References: <18383@bellcore.bellcore.com>
Organization: Albert Einstein Coll. of Med., NY
Lines: 22

In article <18383@bellcore.bellcore.com>, ephs@roy..bellcore.com (Barbara Chalfonte) writes:
> 
> We have a _raging_ controversy here that standard sources of information have
> failed to resolve.  Is saliva basic or acidic?  I thought acidic, in keeping
> in line with the rest of the GI tract, my office-mate thought basic, being
> the exception to the GI tract.  So which is it?  
	
	Actually, yard for yard, most of the digestive tract is basic.
True, the stomach is pH 2, and the first third of duodenum is buffered
only by the food, which makes it about pH 4-5, but from the common bile
duct on, enough bicarbonate is pumped in to put the jejunem, ileum, and
colon on the basic side of neutral.
	Aside from discovering that pH paper tastes horrible, all I can
say is that saliva appears to have so little buffering capacity, and is so
close to neutral that I only tell that it's between 6.5 and 7.5. My
personal guess would be acidic, if only because of the dissolved carbonic
acid resulting from the CO2 being exhaled. 
-- 
	        Craig Werner   (future MD/PhD, 4.5 years down, 2.5 to go)
	     werner@aecom.YU.EDU -- Albert Einstein College of Medicine
              (1935-14E Eastchester Rd., Bronx NY 10461, 212-931-2517)
                   "Viruses do to cells what Groucho did to Freedonia."


Brought to you by Super Global Mega Corp .com