Hi, Eric

I know a little bit about this topic.  We only do 13C and 15N of DOC and POC in the stream water.  All bottles need to be acid (10% HCl) washed before sampling.  The water samples are kept in ice immediately after they are collected. We filter water samples within at most 12hrs.  Filters (for poc) and filtrates (for DOC) are preserved in the freezer until analysis.  

It is not much of hlep. I am intrested in this topic too.  If you get any comments or inputs from others, I would appreciate if you can share with me.  Thanks,

Yuehan
Yuehan Lu, Ph.D.
Mellon Postdoctoral Researcher
Keck Environmental Research Laboratory
College of William and Mary
Virginia Institute of Marine Sciences


---- Original message ----
>Date: Thu, 11 Dec 2008 12:16:58 -0800
>From: Eric Huber <[log in to unmask]>  
>Subject: [ISOGEOCHEM] stream and estuary water storage  
>To: [log in to unmask]
>
>Dear ISOGEOCHEM,
>  I am an aquatic ecologist who will be performing LA-MC-ICPMS on fish
>otoliths. I am interested in learning about the best ways to store
>stream water and estuary water for isotopic analysis of 18O & 87Sr, and
>possibly 13C & 35S.  I'd also like to be able to analyze the water for
>elemental concentrations of Sr, Ba, and Ca.  How much water will I need?
>Can I get away with using 20 ml scintillation vials or do I need to use
>bigger bottles? Do I need to acid wash my vials or bottles?  If so, what
>is the best technique?  What is the best way to cap the vials or bottles
>to prevent fractionation?  Do I have to filter my samples in the field
>or can I wait until I get back to the lab?  Should I keep my samples in
>the dark and on ice while I'm out in the field? Must I add HgCl2 to my
>samples or can I add a less poisonous substance?  If so, how much do I
>need to add and does it have to be done in the field or can it wait
>until I get back to the lab?  Once back at the lab, should I keep my
>samples at room temperature, in the refrigerator, or in the freezer? 
>Chances are that it will be a few months to a year before we analyze the
>water if that is ok.  Any input is greatly appreciated!
>Thanks,
>Eric Huber
>-- 
>Eric R. Huber
>Staff Research Associate II
>Carlson Lab
>University of California, Berkeley
>Dept. of Environmental Science, Policy, and Management
>140 Mulford Hall #3114
>Berkeley, CA 94720
>510-643-9688 (office)
>508-446-5433 (cell)
>510-643-5438 (fax)
>Office: 304 Mulford Hall