东山湾海马齿(Sesuvium portulacastrum)中15种常量和微量元素分析及其风险评价

Analysis and risk assessment for the 15 kinds of major or trace elements of Sesuvium portulacastrum grown in Dongshan Bay

为了解海马齿(Sesuvium portulacastrum)体内无机元素水平,为其再利用提供基础数据,研究测定了东山湾海域生长的海马齿中钾、钠、钙、镁、铜、锌、铅、镉等15种无机元素含量,并进行污染状况和健康风险评价。结果表明:海马齿富含多种矿物质元素,呈根>茎、叶的分布规律(钠和钾除外),钠在植株内的迁移能力最强,铁、锰最弱,各元素在叶和茎中的含量呈Na>K>Mg>Ca>Fe/Mn>Zn>Cu>As>Cr/Ni>Se>Pb>Cd>Hg的规律,在根中含量则呈Na/K>Mg/Mn/Fe/Ca>Zn>Cu>Cr/Ni/Pb>As>Se>Cd>Hg的趋势;海马齿叶和茎的钠钾比分别高达8.58和3.84,这是对盐生环境的应激结果,并使其具有天然咸味;海马齿重金属污染水平极低,单因子污染指数均小于0.2,无机砷和铅的暴露边界比MOE分别为545和48,元素膳食摄入总复合风险TTHQ为0.099,总非致癌风险Rn为0.14,致癌风险Rc为8.24×10^(-6),膳食暴露水平较低,被食用后人体健康风险较低,不会对暴露人群构成明显危害。

In order to understand the pollution status of Sesuvium portulacastrum grown by seawater in Dongshan Bay,and to provide basic data for its reutilization,15 kinds of inorganic elements such as K,Na,Cu,Zn,Pb,and Cd were detected.The result showed that Sesuvium portulacastrum was rich in mineral elements with the distribution as root>stem or leaf except Na and K.And it also seemed the contents of those elements in leave or stem with the distribution by Na>K>Mg>Ca>Fe/Mn>Zn>Cu>As>Cr/Ni>Se>Pb>Cd>Hg and the distribution in root was Na/K>Mg/Mn/Fe/Ca>Zn>Cu>Cr/Ni/Pb>As>Se>Cd>Hg.And the migration ability of Na was the strongest while the migration ability of Fe/Mn was the weakest.The Na/K ratio of stem and leaf was up to 8.58 and 3.84 respectively because of the stress on saline environment and it seemed to make S.portulacastrum tasted natural salty.Lastly,since the single factor pollution indexes were all less than 0.2,the MOE of inorganic arsenic and lead was 545 and 48 respectively,TTHQ was 0.099,Rn was 0.14 and Rc was 8.24×10^(-6).The populations exposed was harmless and the value for the level of the heavy metal pollution,the dietary exposure and the health risk of S.portulacastrum were relatively low.