Hidalgo-Lasso Daniel, García-Villacís Karina, Urvina Ulloa Jeaneth, Marín Tapia Darwin, Gómez Ortega Patricio, Coulon Frederic
Centro de Investigación de Tecnologías Ambientales del Proyecto Amazonía Viva, Empresa Pública de Hidrocarburos EP PETROECUADOR, 4 1/2 km vía Joya de los Sachas-Coca, Joya de los Sachas, 2201010, Ecuador.
School of Water, Energy and Environment, Cranfield University, Cranfield, MK43 0AL, United Kingdom.
Heliyon. 2024 Apr 27;10(9):e30395. doi: 10.1016/j.heliyon.2024.e30395. eCollection 2024 May 15.
In Ecuador, the regulatory framework for the remediation of petroleum-contaminated soils is based on predefined concentration endpoints for a selected range of petroleum hydrocarbon compounds. However, such approach may lead to over or under-estimation of the environmental risk posed by contaminated soils. In this study, the end-point remediation criteria according to Ecuadorian Environmental legislation were evaluated using different approaches. The first one was based on Total Extractable Petroleum Hydrocarbons (TEPH) and the second one on Total Bioavailable Petroleum Hydrocarbons (TBPH). Both were compared with ecotoxicological determinations using EC -Microtox® bioassay at 5 and 15 min of exposure. The correlation (R) between EC values vs TEPH was of 0.2 and 0.25 for 5 and 15 min, respectively. Meanwhile, R between EC and TBPH was of 0.9 and 0.65 for 5 and 15 min, respectively, demonstrating a stronger correlation. Our results suggest that a contaminated site where the concentration of the TEPH is higher than the relevant regulatory concentrations may be deemed to present an acceptable risk even though their concentrations exceed the target values in soils. The results also challenge the notion that hormesis is associated with TEPH, contrary to some literature. This study is the first in Ecuador to propose incorporating bioavailability into environmental regulations, highlighting the need for further research to establish realistic and achievable remediation goals based on toxicity studies involving various trophic levels.
在厄瓜多尔，石油污染土壤修复的监管框架基于一系列选定的石油烃化合物的预定义浓度终点。然而，这种方法可能会导致对污染土壤所造成的环境风险的高估或低估。在本研究中，根据厄瓜多尔环境立法的终点修复标准使用不同方法进行了评估。第一种方法基于总可提取石油烃（TEPH），第二种方法基于总生物可利用石油烃（TBPH）。将两者与使用EC -Microtox®生物测定法在暴露5分钟和15分钟时的生态毒理学测定结果进行了比较。对于5分钟和15分钟，EC值与TEPH之间的相关性（R）分别为0.2和0.25。同时，对于5分钟和15分钟，EC与TBPH之间的R分别为0.9和0.65，表明相关性更强。我们的结果表明，即使总可提取石油烃的浓度超过土壤中的目标值，一个总可提取石油烃浓度高于相关监管浓度的污染场地仍可能被认为具有可接受的风险。结果还对与总可提取石油烃相关的兴奋效应这一观点提出了挑战，这与一些文献的观点相反。本研究是厄瓜多尔首次提出将生物可利用性纳入环境法规，强调需要进一步开展研究，以便基于涉及不同营养级的毒性研究来确立现实且可实现的修复目标。
