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Key research themes
1. What are the environmental and health impacts of hydrocarbon pollution from oil and gas extraction and processing operations?
This research theme investigates the multiple pathways through which hydrocarbon pollution arising from unconventional oil and gas (UOG) operations and conventional petroleum refining impact environmental quality and human health, focusing on air, water, and soil contamination. Emphasis is placed on the release of volatile organic compounds (VOCs), heavy metals, endocrine disrupting chemicals (EDCs), and their consequences for reproductive, developmental, and ecosystem health. This theme matters due to increasing UOG activity and the pernicious nature of related pollutants with proven toxicity and carcinogenicity, calling for rigorous exposure assessment and mitigation strategies.
Key finding: This study synthesizes evidence showing that chemicals released throughout UOG processes—including VOCs (such as benzene, toluene, ethylbenzene, xylene) and heavy metals (arsenic, cadmium, lead)—are linked to adverse... Read more
Key finding: This review documents that VOC and nitrogen oxide emissions from oil and gas production in the US have increased notably over the past decade, with certain "super-emitters" contributing disproportionately to pollution loads.... Read more
Key finding: This work explicates that VOC emissions occur across all stages of the oil and gas fuel cycle—production, processing, transportation, and storage—and that these hydrocarbons strongly contribute to tropospheric ozone formation... Read more
Key finding: By analyzing emissions data and ambient particulate matter (PM2.5) concentrations around a Ghanaian oil refinery, this study connects petroleum emissions—including VOCs, PAHs, and heavy metals—with environmental contamination... Read more
2. How do hydrocarbon pollutants affect soil and sediment microbial communities and biodegradation potential?
This theme explores the changes in microbial biomass, enzymatic activity, and biodegradation capacity of soils and sediments contaminated with different hydrocarbon types. It examines how soil texture, hydrocarbon composition, and pollutant concentration influence microbial community structure and function, which are critical for natural attenuation and bioremediation of hydrocarbon pollutants. Understanding these interactions informs remediation strategies and ecological risk assessments in petroleum-impacted environments.
Key finding: The study demonstrated that gasoline exerted the highest toxicity to microbial biomass and enzyme activities compared to diesel and crude petroleum, with greater effects observed in sandy soils than in clay soils. Hydrocarbon... Read more
Key finding: This comprehensive synthesis links heavy metal contaminants inherently present in crude oil with inhibited microbial degradation of hydrocarbons in soil, as heavy metals suppress microbial enzymatic activity. The paper also... Read more
Key finding: This experimental study isolated six Streptomyces actinomycetes strains from oil refinery-contaminated soil demonstrating significant degradation capacity of crude oil in mineral salt media. These findings provide specific... Read more
Key finding: The isolation of a Streptomyces cinereoruber strain producing extracellular antibacterial substances illustrates the dual role of actinomycetes in biodegradation and biocontrol within contaminated soils. While focused on... Read more
3. How can geophysical methods advance the detection and monitoring of hydrocarbon contamination in soil and groundwater?
The third research theme addresses the application of geophysical imaging—principally electrical resistivity tomography (ERT), vertical electrical sounding (VES), and ground penetrating radar (GPR)—to spatially characterize subsurface hydrocarbon contamination plumes. These noninvasive techniques enable delineation of contaminant extent, depth, and heterogeneity, improving monitoring capabilities and informing remediation design. Integrated geophysical approaches provide critical data for environmental assessments of polluted hydrocarbon exploration and spill sites.
Key finding: The study successfully used VES and ERT to detect high-resistivity anomalies associated with oil-contaminated plumes in aquifers near Romanian oil refineries. The resistivity pseudosections revealed spatial heterogeneity and... Read more
Key finding: This work presents long-term VES monitoring of saltwater intrusion and fault-related meteoric water infiltration affecting aquifers proximate to oil refining activities. Apparent resistivity data captured temporal changes in... Read more
Key finding: By integrating ERT, GPR, and VES datasets at a hydrocarbon spill site in Ogoniland, Nigeria, this investigation delineated contaminant plumes with significantly elevated resistivity (1000–10,000 Ωm), consistent with... Read more
Key finding: While not geophysical in a strict sense, this study contributes a low-cost optical sensor employing LEDs and photoreceptors to reliably detect hydrocarbons on water surfaces by differential light absorption. The white-light... Read more