Liu Minxia, Han Zhiqiang, Yang Yuyi
College of Forestry, Shanxi Agricultural University Taigu 030801 China.
Periodical Press of Shanxi Agricultural University Taigu 030801 China.
RSC Adv. 2019 Jul 15;9(38):21893-21902. doi: 10.1039/c9ra03479j. eCollection 2019 Jul 11.
The Fenhe River basin is the main agricultural and industrial developed area in Shanxi province, China. In recent years, agricultural non-point source pollution in the Fenhe River basin intensified, threatening soil quality and safety in the area. Accumulation of eight heavy metals (HMs) including chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) has been detected in soil samples from 50 agricultural sites (0-20 cm) from the middle reaches of the Fenhe River basin. The ecological and human health risk and potential sources of the eight HMs were investigated. In addition, the human health and ecological risks imposed by the possible sources of the eight HMs were quantitatively apportioned. The enrichment factor (EF) values of Cr, Ni, Cu, Pb and Zn were lower than 2, indicating minimal enrichment, while values for As, Cd and Hg were between 2 and 5, exhibiting moderate enrichment. Temporal variation analysis suggested that most HMs in the study area exhibited low concentrations after 2015, except As. The potential ecological risk index was 174.09, indicating low ecological risk. The total hazard index and cancer risk values were 0.395 and 5.35 × 10 for adults and 2.75 and 3.63 × 10 for children, indicating the accepted standard levels were exceeded for non-carcinogenic risk for children and carcinogenic risks for both adults and children. Four potential sources were identified: (1) natural sources, (2) farming activities, (3) coal combustion, and (4) exhaust emissions. Natural sources represented the largest contributor to ecological risk, accounting for 57.42% of the total. Coal combustion was the major contributor to human health risks, accounting for 43.27% and 43.73% of the total non-carcinogenic risk and carcinogenic risk for adults, respectively, and 42.72% and 43.88% for children, respectively.
汾河流域是中国山西省主要的农业和工业发达地区。近年来，汾河流域农业面源污染加剧，威胁着该地区的土壤质量和安全。在汾河流域中游50个农业站点（0 - 20厘米）的土壤样本中检测到了包括铬（Cr）、镍（Ni）、铜（Cu）、锌（Zn）、砷（As）、镉（Cd）、铅（Pb）和汞（Hg）在内的8种重金属的积累。对这8种重金属的生态和人类健康风险以及潜在来源进行了调查。此外，还对这8种重金属可能来源所带来的人类健康和生态风险进行了定量分配。铬、镍、铜、铅和锌的富集因子（EF）值低于2，表明富集程度最低，而砷、镉和汞的值在2至5之间，呈现中等富集。时间变化分析表明，除砷外，研究区域内大多数重金属在2015年后浓度较低。潜在生态风险指数为174.09，表明生态风险较低。成人的总危害指数和癌症风险值分别为0.395和5.35×10，儿童的分别为2.75和3.63×10，表明儿童的非致癌风险以及成人和儿童的致癌风险均超过了可接受标准水平。确定了四个潜在来源：（1）自然来源，（2）农业活动，（3）煤炭燃烧，（4）废气排放。自然来源是生态风险的最大贡献者，占总量的57.42%。煤炭燃烧是人类健康风险的主要贡献者，分别占成人总非致癌风险和致癌风险的43.27%和43.73%，儿童的分别占42.72%和43.88%。
