Arsenic accumulation in livers of pinnipeds, seabirds and sea turtles: subcellular distribution and interaction between arsenobetaine and glycine betaine.
Concentrations of total arsenic and individual arsenic compounds were determined in liver samples of pinnipeds (northern fur seal Callorhinus ursinus and ringed seal Pusa hispida), seabirds (black-footed albatross Diomedea nigripes and black-tailed gull Larus crassirostris) and sea turtles (hawksbill turtle Eretmochelys imbricata and green turtle Chelonia mydas). Among these species, the black-footed albatross contained the highest hepatic arsenic concentration (5.8+/-3.7 microg/g wet mass). Arsenobetaine was the major arsenic species found in the liver of all these higher tropic marine animals. To investigate the cause of high accumulation of arsenobetaine, subcellular distribution of arsenic and relationship between arsenobetaine and glycine betaine concentrations were examined in the livers of these animals. There was no relationship between total arsenic concentration and its subcellular distribution in liver tissues. However, a significant negative correlation was found between arsenobetaine and glycine betaine concentrations in the liver of six species examined. This result may indicate that arsenobetaine is accumulated in these marine animals as an osmolyte along with glycine betaine, which is a predominant osmolyte in marine animals because the chemical structure and properties of arsenobetaine are similar to those of glycine betaine.
Fujihara
Junko
J
Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan.
Kunito
Takashi
T
Kubota
Reiji
R
Tanabe
Shinsuke
S
D000818:Animals; D001151:Arsenic / Q000032:analysis* / Q000737:chemistry / Q000493:pharmacokinetics; D001152:Arsenicals / Q000378:metabolism*; D001622:Betaine / Q000378:metabolism*; D001717:Birds / Q000378:metabolism*; D002458:Cell Fractionation; D002467:Cell Nucleus / Q000737:chemistry; D003600:Cytosol / Q000737:chemistry; D008099:Liver / Q000737:chemistry*; D008862:Microsomes, Liver / Q000737:chemistry; D008930:Mitochondria, Liver / Q000737:chemistry; D046048:Seals, Earless / Q000378:metabolism*; D014018:Tissue Distribution; D014426:Turtles / Q000378:metabolism*
D001152:Arsenicals; D001622:Betaine; D001151:Arsenic; C038992:arsenobetaine