U.S. Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan.
Korea Biochar Research Center & Division of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, South Korea.
Chemosphere. 2019 Apr;220:651-657. doi: 10.1016/j.chemosphere.2018.12.102. Epub 2018 Dec 17.
The assessment of benzene, toluene, ethyl-benzene, and xylene (BTEX)-contaminated soil toxicity was performed using a sulfur-oxidizing bacteria (SOB) assay. The experiments were set up using an individual pollutant in a 25-mL bottle sealed with a rubber stopper and aluminum cap since BTEX are volatile. A large headspace volume (14 mL) was kept in the reactors to provide enough oxygen for the SOB. Soil samples were spiked with BTEX compounds in the concentration range of 1-1000 mg/kg. In reactors without BTEX compounds, approximately 85% of the theoretically required oxygen was consumed. Whereas, the reactors with benzene consumed in the range of 82-64% (5-100 mg/kg), those with toluene consumed 76-53% (1-50 mg/kg), those with ethyl-benzene consumed 44-71% (5-100 mg/kg), and those with xylene consumed 64-71% (1-10 mg/kg) of the theoretically required oxygen. The effective concentrations responsible for 50% growth inhibition (EC) for benzene, toluene, ethyl-benzene, and xylene detection were 130.2, 1.2, 15.2, and 0.7 mg/kg, respectively. These results suggest that this SOB-based bioassay can detect BTEX pollutants in soils.
采用硫氧化细菌（SOB）测定法对苯、甲苯、乙苯和二甲苯（BTEX）污染土壤的毒性进行了评估。由于 BTEX 具有挥发性，因此在实验中使用 25mL 瓶，通过橡胶塞和铝盖密封，将单个污染物单独置于瓶中。在反应器中保持较大的顶空体积（14mL），为 SOB 提供足够的氧气。土壤样品中 BTEX 化合物的浓度范围为 1-1000mg/kg。在没有 BTEX 化合物的反应器中，大约消耗了 85%理论上所需的氧气。而苯的反应器消耗了 82-64%（5-100mg/kg），甲苯的反应器消耗了 76-53%（1-50mg/kg），乙苯的反应器消耗了 44-71%（5-100mg/kg），二甲苯的反应器消耗了 64-71%（1-10mg/kg）的理论需氧量。苯、甲苯、乙苯和二甲苯的 50%生长抑制有效浓度（EC）分别为 130.2、1.2、15.2 和 0.7mg/kg。这些结果表明，这种基于 SOB 的生物测定法可用于检测土壤中的 BTEX 污染物。
