Van Hop Nguyen, Thi Quynh Dieu Hoang, Hai Phong Nguyen
Department of Chemistry, College of Sciences, Hue University, 77 Nguyen Hue Str., Hue City, Vietnam.
Environ Monit Assess. 2017 Jun;189(6):299. doi: 10.1007/s10661-017-5995-2. Epub 2017 May 29.
The concentrations of seven toxic metals (cadmium (Cd), nickel (Ni), chromium (Cr), arsenic (As), lead (Pb), copper (Cu), and zinc (Zn)) were determined in sediments and the soft tissues of a bivalve species (Meretrix lyrata) collected from the Tien Estuary in Tien Giang Province, South Vietnam. The total metal concentrations in sediments (mg/kg dry weight) increased as Cd (0.06) < Cu (5.0) < Pb (13.9) < As (16.3) < Ni (24) < Cr (50) < Zn (62). Speciation analysis revealed that these metals existed mainly in the residual fraction (43-94%), followed by the Fe-Mn oxide-bound (5-35%) and organic/sulfide-bound (0.6-9.2%) fractions. The metal concentrations in M. lyrata (mg/kg dry weight) were in the ranges of 1.3-1.9 (Cd), 1.5-2.8 (Ni), 1.8-3.4 (Cr), 11-16 (As), 0.3-0.6 (Pb), 6.9-8.7 (Cu), and 95-128 (Zn), which are safe for human consumption. The order of the mean biota-sediment accumulation factor (BSAF) of the metals in the non-residual fractions of the sediment for M. lyrata was Cd > Cu > As > Zn > Cr > Ni > Pb. The Risk Assessment Codes (RACs) suggest that the highest mobility of Cd (with RAC = 37%) poses greater environmental risk to aquatic biota. Correlation analysis results show that M. lyrata can be used as a biomonitor of Cd and Cu pollution in the exchangeable, acid-soluble, and non-residual sediment fractions.
测定了从越南南部同塔省天江的天河口采集的沉积物和一种双壳贝类（泥蚶）软组织中七种有毒金属（镉（Cd）、镍（Ni）、铬（Cr）、砷（As）、铅（Pb）、铜（Cu）和锌（Zn））的浓度。沉积物中金属的总浓度（毫克/千克干重）增加顺序为：镉（0.06）＜铜（5.0）＜铅（13.9）＜砷（16.3）＜镍（24）＜铬（50）＜锌（62）。形态分析表明，这些金属主要以残渣态（43 - 94%）存在，其次是铁锰氧化物结合态（5 - 35%）和有机/硫化物结合态（0.6 - 9.2%）。泥蚶中的金属浓度（毫克/千克干重）范围为：镉1.3 - 1.9、镍1.5 - 2.8、铬1.8 - 3.4、砷11 - 16、铅0.3 - 0.6、铜6.9 - 8.7、锌95 - 128，这些浓度对人类食用是安全的。泥蚶沉积物非残渣态中金属的平均生物群 - 沉积物积累因子（BSAF）顺序为：镉＞铜＞砷＞锌＞铬＞镍＞铅。风险评估代码（RACs）表明，镉的迁移率最高（RAC = 37%），对水生生物群构成更大的环境风险。相关性分析结果表明，泥蚶可作为可交换、酸溶性和非残渣态沉积物中镉和铜污染的生物监测器。
