Graduated Student of Master of Science in Environmental Geology at Shahid Bahonar University of Kerman, Kerman, Iran.
Environ Sci Pollut Res Int. 2020 Jun;27(18):23094-23107. doi: 10.1007/s11356-020-08585-8. Epub 2020 Apr 24.
Urban dust contamination is becoming progressively noticeable, and heavy metals are primary pollutants in urban environments. The contamination of heavy metals in urban dust has been affecting the urban citizens due to their adverse effects on human health, and understanding their effects is a crucial stage for its management. This study is a review of the reports of heavy metal pollution in urban dust of 16 cities in Iran, aimed at determining pollution status and health risk calculation on the nationwide scale, using geo-accumulation index (Igeo), potential ecological risk index (PER), and health risk assessment model. Six toxic elements, namely cadmium, copper, chromium, nickel, lead, and zinc were evaluated in this study. The results presented that the total heavy metal concentrations in the studied cities decreased in the sequences of Zn > Cu > Pb > Ni > Cr > Cd. The average concentrations of Cd, Cu, Ni, Pb, and Zn in the studied cities exceeded the Iran Standard Soil limits for residential areas. The mean levels of studied heavy metals for cities was in the order of Kermanshah > Tehran > Tabriz > Rafsanjan > Hamedan > Isfahan > Mashhad > Ahvaz > Abadan > Kerman > Bushehr > Kashan > Shiraz > Zahedan > Masjed-e-Soleiman > Arak. The Results of Igeo revealed that the pollution levels of Cd, Cu, Pb, Ni, Cr, and Zn in the studied cities ranged from unpolluted to moderate pollution categorizations. The mean potential ecological risk factor (E) values were below (E < 40), showing a low ecological risk level. Also, E values for all cities showed that Cd, Pb, and Cr had the highest ecological risks than other heavy metals. However, the total potential ecological risk index (RI) values for studied cities were 172.1, showing a moderate ecological risk level. Human health risk assessment evaluation showed that in contrast to adults, children have more possible health risks (non-carcinogenic). Among the multiple pathways of exposure, the ingestion pathway was the most important exposure for both groups of population, followed by skin exposure and then breathing exposure. Total hazard index (HI) values among three exposure routes, were less than harmless level (HI < 1), displaying that there was not a non-carcinogenic risk for both groups of population. Cancer risk (CR) study exhibited that the potential risk of cancer decreases in the order of chromium > nickel > cadmium. The CR ranks of chromium, nickel, and cadmium were less than the maximum permissible level, presented an insignificant carcinogenic risk.
城市灰尘污染日益显著，重金属是城市环境中的主要污染物。由于重金属对人类健康的负面影响，城市灰尘中重金属的污染已对城市居民造成影响，了解其影响是管理的关键阶段。本研究综述了伊朗 16 个城市城市灰尘中重金属污染的报告，旨在确定全国范围内的污染状况和健康风险计算，使用地质累积指数（Igeo）、潜在生态风险指数（PER）和健康风险评估模型。本研究评估了镉、铜、铬、镍、铅和锌等六种有毒元素。结果表明，研究城市的重金属总浓度按 Zn > Cu > Pb > Ni > Cr > Cd 的顺序递减。研究城市中 Cd、Cu、Ni、Pb 和 Zn 的平均浓度超过了伊朗住宅区的标准土壤限值。研究城市中重金属的平均水平顺序为克尔曼沙阿>德黑兰>大不里士>拉夫桑詹>哈马丹>伊斯法罕>马什哈德>阿瓦士>阿巴丹> 克尔曼>布什尔>卡尚>设拉子>扎黑丹>马苏德·索莱曼>阿拉克。Igeo 的结果表明，研究城市中 Cd、Cu、Pb、Ni、Cr 和 Zn 的污染水平从无污染到中度污染不等。平均潜在生态风险因子（E）值低于（E<40），表明生态风险水平较低。此外，所有城市的 E 值表明，Cd、Pb 和 Cr 比其他重金属具有更高的生态风险。然而，研究城市的总潜在生态风险指数（RI）值为 172.1，表明生态风险处于中等水平。人类健康风险评估评估表明，与成年人相比，儿童面临更大的健康风险（非致癌性）。在多种暴露途径中，摄入途径是两组人群最重要的暴露途径，其次是皮肤暴露，然后是呼吸暴露。三种暴露途径的总危害指数（HI）值均低于无害水平（HI<1），表明两组人群均不存在非致癌风险。癌症风险（CR）研究表明，癌症风险按铬>镍>镉的顺序降低。铬、镍和镉的 CR 等级均低于最大允许水平，表明致癌风险较小。
