Environmental Ecological Risk Assessment Research Articles

Prediction study on the distribution of polycyclic aromatic hydrocarbons and their halogenated derivatives in the atmospheric particulate phase

Polycyclic aromatic hydrocarbons (PAHs) and their halogenated derivatives (X-PAHs), which generally produced from photochemical and thermal reactions of parent PAHs, widely exist in the environment. They are semi-volatile organic chemicals (SVOCs) and the partitioning between gas/particulate phases affects their environmental migration, transformation and fate, which further impacts their toxicity and health risk to human. However, there is a large data missing of the experimental distribution ratio in the atmospheric particulate phase (f), especially for X-PAHs. In this study, we first checked the correlation between experimental f values of 53 PAH derivatives and their octanol-air partitioning coefficients (log KOA), which is frequently used to characterize the distribution of chemicals in organic phase, and yielded R2 = 0.803. Then, quantum chemical descriptors derived from molecular structural optimization by M06–2X/6–311 +G (d,p) method were further employed to develop Quantitative Structure-Property Relationship (QSPR) model. The model contains two descriptors, the average molecular polarizability (α) and the equilibrium parameter of molecular electrostatic potential (τ), and yields better performance with R2 = 0.846 and RMSE = 0.122. The mechanism analysis and validation results by different strategies prove that the model can reveal the molecular properties that dominate the distribution between gas and particulate phases and it can be used to predict f values of other PAHs/X-PAHs, providing basic data for their environmental ecological risk assessment.

An environmental risk assessment framework for enhanced oil recovery solutions from offshore oil and gas industry

Environmental risk assessments are necessary to understand the risk associated with enhanced oil recovery (EOR) solutions and to provide decision support for choosing the best technology and implementing risk-reducing measures. This study presents a review of potentially relevant environmental/ecological risk assessment (ERA) guidelines and, based on this review, proposes an initial suggestion of an ERA framework for understanding the environmental impacts from EOR solutions. We first shortlist the important elements necessary for conducting an ERA of EOR solutions from the selected guidelines. These elements are then used to build the suggested ERA framework for produced water discharges, drilling discharges and emissions to air from EOR solutions, which is the primary objective of the present study. Furthermore, the emphasis is placed on identifying the knowledge gaps that exist for conducting ERA of EOR processes. In order to link the framework with the current best environmental practices, a review of environmental policies applicable to the marine environment around the European Union (EU) was conducted. Finally, some major challenges in the application of ERA methods for novel EOR technologies, i.e. uncertainties in the ERA due to lack of data and aggregation of risk from different environmental impacts, are discussed in detail. The frameworks suggested in this study should be possible to use by relevant stakeholders to assess environmental risk from enhanced oil recovery solutions.

CSChE chemical spill environmental/ecological risk assessment guideline development

AbstractThe Canadian Society for Chemical Engineering (CSChE) Process Safety Management (PSM) Division, with representation from the chemical and oil industry, government, and some other interested parties, concluded that there is no guideline commonly recognized by the chemical industries in Canada for conducting environmental/ecological risk assessments (ERA) involving postulated acute chemical/energy product spills from facilities of interest. These facilities would include those that produce, process, store, distribute, handle, or transport chemicals or energy products. This paper explains the need for this type of guideline in Canada. It will also describe the expertise and stakeholder representation involved in order to optimize credibility and acceptance. Furthermore, it will include information on a proposed scope, objectives, and content for a prospective environmental risk assessment guideline, with an exclusive focus on acute chemical spill events involving fixed and transportation sources. This guideline will also support elements of the proposed CSA Standard on Process Safety Management (PSM).

Toxicity assays of marine sediments from western Venezuela

Refineries are one of the main sources of coastal marine pollution worldwide. In this study, the toxicity of sediments potentially impacted by the Paraguaná Refinery Complex on the west coast of Venezuela was evaluated using chronic toxicity assays. This toxicity was determined by exposing larvae of the shrimp Litopenaeus vannamei and the polychaete Scolelepis texana to bioassays during 28 and 10 days, respectively. Both bioassays indicated that the sediments surrounding the refinery are highly toxic, compared to sediments from the same region farther from the refinery and sediments from a control zone. The sediments surrounding the refinery had relatively high concentrations of total petroleum hydrocarbons (>10,000 ppm); of heavy metals such as chrome, nickel, and zinc; and of polycyclic aromatic hydrocarbons (ΣPAHs > 1000 ppb). This study forms part of the first environmental ecological risk assessment done in Venezuela. The high toxicity of the sediments close to one of the largest refinery complexes in the world should serve as a warning of the possible impacts on benthic and planktonic communities that live in the environs of refineries in coastal marine environments.