Related Experiment Video
Updated: Jun 28, 2026
20:28
A Toolkit to Enable Hydrocarbon Conversion in Aqueous Environments
Published on: October 2, 2012
Geology and Geomorphology Drive Polycyclic Aromatic Compound Concentrations and Composition in Rivers Draining the
Brandon R Hill1, Colin A Cooke1,2, Alberto V Reyes1
1Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada.
Environmental Science & Technology
|March 27, 2025
Summary
Riverine polycyclic aromatic compounds (PACs) in Alberta are mainly from natural bitumen erosion, not mining. This study clarifies contaminant sources in watersheds impacted by oil sands operations.
Area of Science:
- Environmental Chemistry
- Geochemistry
- Ecotoxicology
Background:
- Large-scale open-pit bitumen mining in Alberta raises concerns about polycyclic aromatic compounds (PACs) contamination.
- Bitumen-rich McMurray Formation erosion complicates distinguishing natural from industrial PAC sources in rivers.
Purpose of the Study:
- Quantify PAC concentrations, loads, and yields in rivers draining mining-impacted watersheds.
- Differentiate between natural and anthropogenic PAC inputs in riverine systems.
- Identify primary drivers of PAC transport in affected watersheds.
Main Methods:
- Collected 998 water quality samples upstream and downstream of mining operations.
- Analyzed samples for 48 unsubstituted and alkylated PAC homologues.
- Compared PAC compositional fingerprints to potential natural and industrial sources.
Main Results:
- PAC input and riverine transport are primarily driven by erosion of bituminous outcrops.
- Watershed PAC loads and yields varied with industrial development and outcrop distribution.
- PAC relative abundances shifted, indicating natural sources dominate.
Conclusions:
- Eroding bitumen-rich outcrops, not industrial pollution, are the main source of riverine PACs.
- PAC concentrations are controlled by outcrop presence and river hydrography.
- Study clarifies contaminant sources in bitumen-mining impacted ecosystems.
Related Concept Videos
00:54What are Biogeochemical Cycles?
The most common elements in organic molecules, carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus, are only available in the ecosystem in limited amounts. Therefore, these nutrients must be recycled through both biotic and abiotic components of the ecosystem, in processes generally called biogeochemical cycles.
00:46Bioremediation
Bioremediation is the use of prokaryotes, fungi, or plants to remove pollutants from the environment. This process has been used to remove harmful toxins in groundwater as a byproduct of agricultural run-off and also to clean up oil spills.
01:21Green Algae
Green algae, also referred to as chlorophytes, are different from red algae in having the chloroplasts containing chlorophylls a and b, which give them their distinct green hue. However, they lack phycobiliproteins, preventing them from developing the red or blue-green pigmentation seen in red algae. In terms of photosynthetic pigment composition, green algae closely resemble plants and share a close evolutionary relationship with them. Taxonomically Green algae belong to Phylum Chlorophyta in...
01:25Microbial Bioremediation of Uranium
Microorganisms play a critical role in the transformation and immobilization of uranium in contaminated environments through four main pathways: bioreduction, biosorption, bioaccumulation, and biomineralization. These mechanisms reduce uranium’s toxicity and prevent its migration through groundwater systems, offering sustainable approaches for in situ bioremediation.Bioreduction of UraniumBioreduction is driven by anaerobic bacteria such as certain strains of Geobacter and Shewanella, which use...
01:26Microbial Bioremediation of Hydrocarbons
Bioremediation is an environmentally sustainable process that employs living organisms—primarily microorganisms—to degrade or neutralize pollutants from contaminated environments. In oil spills and hydrocarbon pollution, bioremediation involves the use of hydrocarbon-degrading bacteria to transform toxic compounds into less harmful substances. This approach leverages natural microbial metabolic processes and is considered both cost-effective and ecologically favorable compared to physical or...
01:19Acid Mine Drainage
Mining activities that disturb sulfide-rich rocks, particularly those containing pyrite (FeS₂), initiate a cascade of geochemical and microbiological processes with serious environmental implications. When exposed to air and water, pyrite undergoes oxidation, releasing sulfate, ultimately forming sulfuric acid and mobilizing heavy metals into surrounding water systems. This phenomenon, known as acid mine drainage (AMD), results in low pH waters laden with toxic elements that threaten aquatic...