Background

Heavy metal contamination via mining activity is a serious problem around the world. This study was conducted to evaluate the total non-cancer hazard quotient (THQ) and excess lifetime cancer risks of lead (Pb) and cadmium (Cd) to different population groups via soil, wheat and barley ingestion, soil-dermal contact, and inhalation soil particulates around Shahin mine located in Shazand County.

Methods

Soil and plants were sampled randomly from 60 agricultural fields around Shahin mine. The samples Pb and Cd concentrations were determined using atomic absorption spectroscopy (AAS). The THQ and the excess lifetime cancer risks of Pb and Cd were estimated using the formulas suggested by the U.S. Environmental Protection Agency (USEPA). The Pb non-cancer risk for children (<6 years old) was assessed using the integrated exposure uptake bio-kinetic (IEUBK) model.

Results

The mean contents of Pb (234.47 mg kg⁻¹) and Cd (1.89 mg kg⁻¹) in soil samples were higher than the background values. The mean Pb and Cd concentrations in wheat grains were 0.44 and 0.23 μg g⁻¹ respectively, which were about 6.5 and 5.8 times higher than that was observed in barley grains, respectively. The THQ of Pb and Cd for all groups were greater than 1. The excess lifetime cancer risks of Pb via wheat and barley consumption for all receptor groups were greater than 1 × 10⁻⁶.

Conclusions

Crop ingestion and soil inhalation had the greatest and lowest portions to increase the THQ and excess lifetime cancer risks of Pb and Cd in the study region, respectively.

中文翻译：

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伊朗中部沙赞德县土壤、小麦和大麦中铅和镉的健康风险评估。

背景

采矿活动造成的重金属污染是世界范围内的一个严重问题。本研究旨在评估铅 (Pb) 和镉 (Cd) 通过土壤、小麦和大麦摄入、土壤-皮肤接触和吸入对不同人群的总非癌症危害商 (THQ) 和超额终身癌症风险位于沙赞德县的沙欣矿周围的土壤颗粒。

方法

从沙欣矿周围的 60 个农田中随机抽取土壤和植物。使用原子吸收光谱法 (AAS) 测定样品的 Pb 和 Cd 浓度。使用美国环境保护署 (USEPA) 建议的公式估算 Pb 和 Cd 的 THQ 和超额终生癌症风险。使用综合暴露摄取生物动力学 (IEUBK) 模型评估儿童（<6 岁）的铅非癌症风险。

结果

土壤样品中Pb (234.47 mg kg ^-1 ) 和 Cd (1.89 mg kg ^-1 ) 的平均含量高于背景值。小麦籽粒中 Pb 和 Cd 的平均浓度分别为 0.44 和 0.23 μg g ^-1，分别是大麦籽粒中的 6.5 倍和 5.8 倍。所有组的 Pb 和 Cd 的 THQ 均大于 1。所有受体组通过小麦和大麦摄入 Pb 的超额终生癌症风险均大于 1 × 10 ^-6。

结论

在研究区域，作物摄入和土壤吸入分别增加了 Pb 和 Cd 的 THQ 和超额寿命癌症风险的最大和最低部分。