Environmental Science Research Laboratory, Department of Environmental Science, Faculty of Science, University of Zanjan, Zanjan, 45371-38791, Iran.
Department of Chemistry, Faculty of Science, Guilan University-University Campus, Rasht, Iran.
Environ Sci Pollut Res Int. 2018 Aug;25(24):23725-23735. doi: 10.1007/s11356-018-2455-7. Epub 2018 Jun 6.
Due to the importance of pollution monitoring in marine ecosystems and lack of a coherent and systematic investigation of heavy metal ions along the southern shores of the Caspian Sea, in the present study, the amount of these metals and As ions in coastal waters along its 780-km-long coast in Iran have been studied. Heavy metals (cobalt, nickel, copper, zinc, cadmium, mercury, lead) and a poisonous metalloid (arsenic) were selected in 59 sampling stations and determined using differential pulse polarography method. The multivariate statistical tools were applied to describe and interpret the experimental data. The overall mean concentrations of studied metals (in microgram per liter; μg L) in the samples were found in the order Zn (10.9) > Ni (7.4) > Cu (5.5) > Pb (1.9) > Hg (1.4) > As (1.3) > Co (1.1) > Cd (0.2). The results when compared with reported international standards confirmed that the sampled waters do contain some of these elements above the suggested maximum permissible limits. Hg and Cu were detected in 54.2 and 72.9% of the samples, almost all above the permissible limits. Ni, Zn, Pb, and Co were detected in 100, 96.6, 93.2, and 88.1%, respectively, while 8.5, 22.0, 3.4, and 1.7% were above the permissible limits. Cd and As were present in 61 and 93% of the samples, and their concentrations were higher than the rate presented by Russian System of Management Chemicals (RSMC). In addition, spatial distribution of heavy metal concentrations showed that Gorgan Bay is an ecosystem serving as a filter, trapping natural and anthropogenic materials that are brought from industrial, commercial, and urbanized areas. The multivariate data analysis reveals that Caspian Sea is contaminated by both anthropogenic as well as pedo-geochemical sources.
由于污染监测在海洋生态系统中的重要性，以及对里海南海岸沿海水域重金属离子缺乏一致和系统的调查，本研究对伊朗长达 780 公里的海岸线上这些金属和砷离子的含量进行了研究。在 59 个采样点选择了重金属（钴、镍、铜、锌、镉、汞、铅）和一种有毒类金属（砷），并使用差分脉冲极谱法进行了测定。应用多元统计工具来描述和解释实验数据。在所研究的金属（微克/升；μg/L）的总体平均浓度中，在样品中的顺序为 Zn（10.9）>Ni（7.4）>Cu（5.5）>Pb（1.9）>Hg（1.4）>As（1.3）>Co（1.1）>Cd（0.2）。与国际报道的标准相比，结果证实采样水域确实含有这些元素中的一些，超过了建议的最大允许限制。汞和铜在 54.2%和 72.9%的样品中被检出，几乎都超过了允许的限度。镍、锌、铅和钴分别在 100%、96.6%、93.2%和 88.1%的样品中被检出，而 8.5%、22.0%、3.4%和 1.7%超过了允许的限度。镉和砷在 61%和 93%的样品中存在，其浓度高于俄罗斯化学品管理系统（RSMC）的含量。此外，重金属浓度的空间分布表明，戈尔甘湾是一个充当过滤器的生态系统，捕获了从工业、商业和城市化地区带来的自然和人为物质。多元数据分析表明，里海受到人为和土壤地球化学源的污染。
