Department of Earth Sciences, Shiraz University, Shiraz, Iran.
Health and Environment Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Environ Monit Assess. 2023 Feb 16;195(3):403. doi: 10.1007/s10661-023-10946-y.
Urmia Lake, in the northwest of Iran, is the largest body of saline water in the Middle East, which has been desiccated in recent decades. To investigate the pollution status and ecological-health risks of heavy metals and metalloids in the surface sediments of this lake, 26 sediment samples were collected along the salt marshes of the lake and were analyzed for heavy metals and metalloid concentrations. The potential ecological risk assessment was carried out using enrichment factor (EF), geo-accumulation index (I), contamination factor (CF), and potential ecological risk (E) standard indices. The average concentrations (mg kg) of heavy metals and metalloids were as follows: Fe (11,714) > Sr (320.8) > Mn (274.3) > V (28.5) > Cu (24.7) > Zn (21.2) > As (17.3) > Ni (14.8) > Cr (12.6) > Pb (11) > Co (4.0) > U (1.7), Hg (0.6) > Mo (0.36). The concentrations of As, Hg, and Sr in lake sediments were higher than geochemical background values. The non-carcinogenic risks caused by heavy metals and metalloids were insignificant regarding health risks. Levels of carcinogenic risk for metal(loid)s were in the acceptable ranges (10-10). The ecological risk was low, except for As, Sr, and Hg which showed moderate to significant EF, I, and CF values. Arsenic and Sr were enriched in the surface sediments in desiccated parts of the lake due to complete lake water evaporation. It seems that further drying of the lake increases the potential ecological risk of heavy metals and metalloids in the surface sediments of Urmia Lake.
乌鲁米耶湖位于伊朗西北部，是中东地区最大的盐水体，近几十年来已经干涸。为了调查该湖盐沼地区表层沉积物中重金属和类金属的污染状况和生态健康风险，采集了 26 个沉积物样品进行重金属和类金属浓度分析。采用富集因子（EF）、地积累指数（I）、污染因子（CF）和潜在生态风险（E）标准指数对潜在生态风险进行了评估。重金属和类金属的平均浓度（mg/kg）如下：Fe（11714）>Sr（320.8）>Mn（274.3）>V（28.5）>Cu（24.7）>Zn（21.2）>As（17.3）>Ni（14.8）>Cr（12.6）>Pb（11）>Co（4.0）>U（1.7），Hg（0.6）>Mo（0.36）。湖泊沉积物中 As、Hg 和 Sr 的浓度高于地球化学背景值。重金属和类金属对健康风险造成的非致癌风险可忽略不计。金属（类）的致癌风险水平处于可接受范围（10-10）。除了 As、Sr 和 Hg 具有中等至高的 EF、I 和 CF 值外，生态风险较低。由于湖水完全蒸发，湖泊干涸地区的表层沉积物中砷和锶得到了富集。看来，湖泊进一步干涸会增加乌鲁米耶湖表层沉积物中重金属和类金属的潜在生态风险。
