Predicting the toxicity of chromium in sediments.
Environ Toxicol Chem
; 23(12): 2981-92, 2004 Dec.
Article
em En
| MEDLINE
| ID: mdl-15648774
ABSTRACT
Chromium exists in sediments in two oxidation states Cr(III), which is relatively insoluble and nontoxic, and Cr(VI), which is much more soluble and toxic. Chromium(VI) is thermodynamically unstable in anoxic sediments, and acid-volatile sulfide (AVS) is formed only in anoxic sediments; therefore sediments with measurable AVS concentrations should not contain toxic Cr(VI). If this hypothesis holds true, measuring AVS could form the basis for a theoretically based guideline for Cr in sediments. Ten-day water-only and spiked sediment toxicity tests with the amphipod Ampelisca abdita were performed with Cr(VI) and Cr(III), along with sediments collected from a site contaminated with high concentrations of Cr. In sediments where AVS exceeded analytical detection limits, Cr concentrations in interstitial water were very low (<100 microg/L) and no significant toxicity to A. abdita was observed. In sediments in which AVS was not significantly greater than zero, Cr concentrations in interstitial waters increased significantly, with greater than 90% of the Cr present as Cr(VI), and mortality of A. abdita was elevated. These results demonstrate that measurements of AVS and interstitial water chromium can be useful in predicting the absence of acute effects from Cr contamination in sediments.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sulfetos
/
Poluentes Químicos da Água
/
Carcinógenos Ambientais
/
Monitoramento Ambiental
/
Cromo
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Limite:
Animals
País/Região como assunto:
America do norte
Idioma:
En
Ano de publicação:
2004
Tipo de documento:
Article