State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China.
State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; School of Architecture and Civil Engineering, Chengdu University, Chengdu 610106, Sichuan, China.
J Hazard Mater. 2023 Sep 15;458:132006. doi: 10.1016/j.jhazmat.2023.132006. Epub 2023 Jul 11.
Public awareness of the potential environmental risks of shale gas extraction has increased in recent years. However, the status and environmental risks of potentially toxic metals (PTMs) in shale gas field soil remain unclear. A total of 96 topsoil samples were collected from the first shale gas exploitation area in China. The sources of nine PTMs in the soils were identified using positive matrix factorization and correlation analysis, and the ecological and human health risks of toxic metals from different sources under the two land use types were calculated. The results showed that mean pollution load index (PLI) values for farmland (1.18) and woodland (1.40) indicated moderate pollution, As, Cd and Ni were the most serious contaminants among all nine PTMs. The following four sources were identified: shale gas extraction activities (43.90%), nature sources (31.90%), agricultural and traffic activities (17.55%) and industrial activities (6.55%). For ecological risk, the mean ecological risk index (RI) values for farmlands (161.95) and woodlands (185.27) reaching considerable risk. The contribution ratio of shale gas extraction activities for farmlands and woodlands were 5.70% and 8.90%, respectively. Regarding human health risk, noncarcinogenic risks for adults in farmlands and woodlands were negligible. Industrial activities, agricultural and traffic activities were estimated to be the important sources of health risks. Overall, shale gas extraction activities had little impact on the ecological and human health risk. This study provides scientific evidence regarding the soil contamination potential of shale gas development activities.
近年来，公众对页岩气开采潜在环境风险的认识有所提高。然而，页岩气田土壤中潜在有毒金属（PTMs）的状况和环境风险仍不清楚。本研究共采集了中国首个页岩气开发区 96 个表层土壤样品。采用正定矩阵因子分解和相关性分析，确定了土壤中 9 种 PTMs 的来源，并计算了两种土地利用类型下不同来源有毒金属的生态和人体健康风险。结果表明，农田（1.18）和林地（1.40）的平均污染负荷指数（PLI）值表明存在中度污染，砷（As）、镉（Cd）和镍（Ni）是所有 9 种 PTMs 中最严重的污染物。确定了以下四个来源：页岩气开采活动（43.90%）、自然源（31.90%）、农业和交通活动（17.55%）和工业活动（6.55%）。对于生态风险，农田（161.95）和林地（185.27）的平均生态风险指数（RI）值达到了较高的风险水平。页岩气开采活动对农田和林地的贡献率分别为 5.70%和 8.90%。关于人体健康风险，农田和林地成年人的非致癌风险可忽略不计。工业活动、农业和交通活动被认为是健康风险的重要来源。总体而言，页岩气开采活动对生态和人体健康风险的影响较小。本研究为页岩气开发活动的土壤污染潜力提供了科学依据。
