RefDoc
Haut

Faire une nouvelle recherche
Make a new search
Lancer la recherche


Titre du document / Document title

Ecotoxicology of arsenic in the marine environment

Auteur(s) / Author(s)

NEFF J. M. (1) ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

(1) Battelle Ocean Sciences Laboratory, 397 Washington Street, Duxbury, Massachusetts 02332, ETATS-UNIS

Résumé / Abstract

Arsenic has a complex marine biogeochemistry that has important implications for its toxicity to marine organisms and their consumers, including humans. The average concentration of total arsenic in the ocean is about 1.7 μg/L, about two orders of magnitude higher than the U.S Environmental Protection Agency's human health criterion (fish consumption) value of 0.0175 μg/L. The dominant form of arsenic in oxygenated marine and brackish waters is arsenate (As V). The more toxic and potentially carcinogenic arsenite (As III) rarely accounts for more than 20% of total arsenic in seawater. Uncontaminated marine sediments contain from 5 to about 40 μg/g dry weight total arsenic. Arsenate dominates in oxidized sediments and is associated primarily with iron oxyhydroxides. In reducing marine sediments, arsenate is reduced to arsenite and is associated primarily with sulfide minerals. Marine algae accumulate arsenate from seawater. reduce it to arsenite, and then oxidize the arsenite to a large number of organoarsenic compounds. The algae release arsenite, methylarsonic acid, and dimethylarsinic acid to seawater. Dissolved arsenite and arsenate are more toxic to marine phytoplankton than to marine invertebrates and fish. This may be due to the fact that marine animals have a limited ability to bioconcentrate inorganic arsenic from seawater but can hioaccumulate organoarsenic compounds from their food. Tissues of marine invertebrates and fish contain high concentrations of arsenic, usually in the range of about I to 100 μg/g dry weight, most of it in the form of organoarsenic compounds, particularly arsenohetaine. Organoarsenic compounds are bioaccumulated by human consumers of seafood products, but the arsenic is excreted rapidly, mostly as organoarsenic compounds. Arsenohetaine, the most abundant organoarsenic compound in seafoods, is not toxic or carcinogenic to mammals. Little of the organoarsenic accumulated by humans from seafood is converted to toxic inorganic arsenite. Therefore, marine arsenic represents a low risk to human consumers of fishery products.

Revue / Journal Title

Environmental toxicology and chemistry    ISSN  0730-7268   CODEN ETOCDK 

Source / Source

1997, vol. 16, no5, pp. 917-927 (137 ref.)

Langue / Language

Anglais

Editeur / Publisher

SETAC, Pensacola, FL, ETATS-UNIS  (1982) (Revue)

Mots-clés anglais / English Keywords

Arsenic

;

Pollutant

;

Biological accumulation

;

Water pollution

;

Marine environment

;

Review

;

Mots-clés français / French Keywords

Arsenic

;

Polluant

;

Accumulation biologique

;

Pollution eau

;

Milieu marin

;

Article synthèse

;

Mots-clés espagnols / Spanish Keywords

Arsénico

;

Contaminante

;

Acumulación biológica

;

Contaminación agua

;

Medio marino

;

Artículo síntesis

;

Localisation / Location

INIST-CNRS, Cote INIST : 19956, 35400006534128.0110

Nº notice refdoc (ud4) : 2688781



Faire une nouvelle recherche
Make a new search
Lancer la recherche
Bas