Arsenic was speciated in 46 seaweed samples purchased from the U.S. market, i.e., brown (arame, hijiki, kombu, knotted wrack, oarweed, wakame), green (sea lettuce), and red (dulse, Irish moss, laver, nori) macroalgae. The total arsenic (tAs) concentrations varied from 3000 to 105 000 ng/g (dry weight). Speciation analysis based on the extraction of water-soluble and nonpolar arsenic showed that, among the variety of arsenicals identified, arsenosugars were dominant in most seaweeds. Inorganic arsenic (iAs) did not exceed 350 ng/g except for knotted wrack (1760 ng/g), oarweed (8900–16 000 ng/g), and hijiki (50 800–56 900 ng/g). While arsenate (As⁵⁺) was the predominant form of iAs, arsenite (As³⁺) was also detected in some samples such as oarweed and hijiki. Nonpolar arsenic accounted for 2–59% of the tAs; the highest percentages were in sea lettuce and wakame. Unknown arsenic species were found representing 0.1–12% of the tAs in the seaweeds. Reference materials and spike recovery tests were used for quality control. While the regulations are not applicable to products in the U.S., the iAs concentrations in the seaweeds (except hijiki and oarweed) are lower than the guidance levels established by several countries.

中文翻译：

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海藻中的砷物种可在美国购买

砷是从美国市场购买的46种海藻样品中指定的，即棕色（阿拉木，hijiki，海带，打结残骸，草藻，裙带菜），绿色（海莴苣）和红色（杜勒斯，爱尔兰苔，紫菜，紫菜）大藻。总砷（tAs）浓度在3000至105000 ng / g（干重）之间变化。根据水溶性和非极性砷的提取进行的形态分析表明，在鉴定出的多种砷中，砷糖在大多数海藻中占主导地位。无机砷（iAs）含量不超过350 ng / g，除了打结残骸（1760 ng / g），草浆（8900–16 000 ng / g）和hijiki（50 800–56 900 ng / g）以外。砷（As ⁵⁺）是iAs的主要形式，而砷（As ³⁺）在一些样品中也被检出，如草和hijiki。非极性砷占tAs的2–59％；比例最高的是海生菜和裙带菜。发现未知的砷物种占海藻中tAs的0.1–12％。参考材料和加标回收率测试用于质量控制。尽管该法规不适用于美国的产品，但海藻中的iAs浓度（hijiki和oarweed除外）低于几个国家制定的指导水平。