Agreed. A number of studies found that in marine sediments, Cr was
almost always in the Cr(III) form, even in the proximity of Cr(VI)
groundwater plumes.
Becker DS, Long ER, Proctor DM, Ginn TC (2006) Evaluation of Potential
Toxicity and Bioavailability of Chromium in Sediments Associated With
Chromite Ore Processing Residue. Environmental Toxicology and Chemistry
25, 2576-2583.
Berry WJ, Boothman WS, Serbst JR, Edwards PA (2004) Predicting the
toxicity of chromium in sediments. Environmental Toxicology and
Chemistry 23, 2981-2992.
Graham AM, Wadhawan AR, Bouwer EJ (2009) Chromium occurrence and
speciation in Baltimore Harbor sediments and porewater, Baltimore,
Maryland, USA. Environmental Toxicology and Chemistry 28, 471-480.
Martello L, Fuchsman P, Sorensen M, Magar V, Wenning R (2007) Chromium
Geochemistry and Bioaccumulation in Sediments from the Lower Hackensack
River, New Jersey. Archives of Environmental Contamination and
Toxicology 53, 337-350.
Warren S. Boothman, Research Chemist
U.S. Environmental Protection Agency
National Health and Environmental Effects Research Laboratory
Atlantic Ecology Division
27 Tarzwell Drive
Narragansett, RI 02882
Phone: 401-782-3161
Fax: 401-782-3030
email: [log in to unmask]
From: "Johnson, Thomas Martin" <[log in to unmask]>
To: [log in to unmask]
Date: 09/16/2011 02:54 PM
Subject: Re: Cr in marine sediment
Sent by: "PLASMACHEM-L: Analytical Chem.(ICP's, DCP's, MIP's)."
<[log in to unmask]>
Chromium goes to Cr(VI) only in highly oxidized, and usually alkaline,
environments. If those sediment are anoxic, then almost certainly the
Cr is all Cr(III).
-Tom Johnson
__________________________________
Thomas M. Johnson
University of Illinois at Urbana-Champaign
Associate Professor and Department Head
Department of Geology, MC-102
208 Natural History Building
1301 West Green Street
Urbana, IL 61801
http://www.geology.uiuc.edu/
Phone (217) 244-2002
__________________________________
On Sep 16, 2011, at 1:27 PM, Thomas J. Manning wrote:
Anyone care to guess the oxidation state of chromium in marine sediment
- next to an old stainless steel wall. Green Color suggests CrO3
(neutral = +6 charge) but we have no experience with this species in
this environment. Thanks - have a good weekend! Tm
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