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Characterization, Quantification and Compound-specific Isotopic Analysis of Pyrogenic Carbon Using Benzene Polycarboxylic Acids BPCA
Published on: May 16, 2016
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Polyaromatic hydrocarbons and elements in sediments associated with a suburban railway
Jeffrey M Levengood1, Edward J Heske, Patrick M Wilkins
1Illinois Natural History Survey, Prairie Research Institute, University of Illinois at Urbana-Champaign, 1816 S. Oak St., Champaign, IL, 61820, USA, levengoo@illinois.edu.
Environmental Monitoring and Assessment
|July 30, 2015
Summary
Railroad operations contaminate nearby waterways with polycyclic aromatic hydrocarbons (PAHs) and metals. Contaminant levels were higher downstream and closer to tracks, posing potential risks to aquatic ecosystems.
Area of Science:
- Environmental Science
- Ecotoxicology
- Geochemistry
Background:
- Aquatic ecosystems are vulnerable to contamination from industrial activities.
- Railroad operations can introduce pollutants into adjacent water bodies.
Purpose of the Study:
- To assess polycyclic aromatic hydrocarbon (PAH) and selected elemental concentrations in sediments near a former railroad line.
- To determine the association between railroad proximity and contaminant levels in aquatic sediments.
- To evaluate potential risks to aquatic life posed by identified contaminants.
Main Methods:
- Sediment samples were collected from streams, ditches, and ponds bisected or bordered by the Elgin, Joliet, and Eastern rail line (2009-2011).
- Concentrations of PAHs and elements (including chromium, nickel, mercury, vanadium, lead, and arsenic) were measured.
- Statistical analyses examined relationships between contaminant levels, proximity to the railroad, and location (upstream/downstream).
Main Results:
- Summed PAH concentrations were higher downstream and decreased with distance from the tracks (within 500m).
- Certain PAHs (phenanthrene, dibenzo[a,h]anthracene) exceeded probable effect thresholds.
- Lead and arsenic concentrations were elevated near the railroad but below concern thresholds.
- Nickel and mercury exceeded lower effect levels; vanadium exceeded chronic toxicity thresholds, without clear association to the railroad.
- Chromium levels were below concern thresholds, but valence state was undetermined, limiting risk assessment.
Conclusions:
- Railroad activities contribute environmental contaminants to nearby waterways, particularly downstream.
- Observed contaminant levels suggest potential risks to aquatic life, possibly underestimated due to synergistic effects in complex mixtures.
- Further investigation into chromium valence states and combined contaminant effects is warranted for a comprehensive risk evaluation.
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