No abstract

The qualitative and quantitative analysis of the different arsenic species in Korean oyster samples was performed to provide the vital information of food safety of the marine sample in terms of the arsenic species. Korean marine samples, oysters, were obtained from nine sites in the western and southern areas of South Korea. Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure the total arsenic. The different arsenic species in the oyster were separated by ion chromatography (IC), and then detected by ICP-MS. Extraction of arsenic species was performed with the mixed solvent of the methanol:water (3:1). The extraction efficiency of arsenic species (the ratio of total amount of the different arsenic species to the total arsenic in the oyster) for nine oysters was approximately 73-81%. The major arsenic species in the oyster was arsenobetaine, and its concentration in the samples was in the range of 7-16 mg/kg that was more than 90% of the total organic arsenic in the oyster. As(III) was not generally detected while the trace As(V) was detected in most oysters.Keywords: Arsenic speciation, Korean marine sample, Oyster, Ion chromatography, Inductively coupled plasma-mass spectrometry IntroductionArsenic has been known as a carcinogenic element that might be accumulated and biologically toxic in human body. [1][2][3][4][5] The element exists in various chemical forms, including trivalent and pentavalent states, inorganic and organic compounds, and about 30 different chemical species has been reported ( Table 1). In general, arsenic species are classified as inorganic arsenic and organic arsenic species. Inorganic arsenic species were formed with oxygen, sodium, chlorine, and sulfur. Organic arsenic species were formed with carbon, hydrogen, and oxygen existed in the animal and plant. 4 Even though the toxicological mechanism was not revealed, the inorganic arsenic species have been reported to be more toxic than organic arsenic species. 6,7 In particular, arsenite (As(III)) is more toxic than arsenate (As(V)). As a small amount of inorganic arsenic species have been known to be fatal to human being, it had been used as an assassination chemical and deadly drug in the middle ages. But arsenobetaine (AsB) and arsenocholine (AsC) of organic arsenic species have been known to be nontoxic species. [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] In general, sea water includes 3 μg/kg of arsenic, and the arsenic can be accumulated and transformed to the different chemical forms in a marine life. 23 Arsenics are abundant in fishes, crustacean (lobster, shrimp, and crab), clam, and seaweed, and the chemical forms of arsenic are organic species that be easily excreted from the human body. In addition, inorganic arsenic could not be formed in a metabolism of organic arsenic in a mammal due to the strong bond of arsenic and carbon. Methylarsonic acid (MMA) and dimethylarsinic acid (DMA) could be restrictively metabolized, and excreted in a urine without changes of the chemical forms. Accordingly...