The use of chlorate, nitrate, and perchlorate to promote crude oil mineralization in salt marsh sediments

TitleThe use of chlorate, nitrate, and perchlorate to promote crude oil mineralization in salt marsh sediments
Publication TypeJournal Article
Year of Publication2015
AuthorsBrundrett M, Horita J, Anderson T, Pardue J, Reible D, W. Jackson A
JournalEnvironmental Science and Pollution Research
Date PublishedOct
ISBN Number0944-1344
Accession NumberWOS:000363966900016
KeywordsDeepwater Horizon Oil Spill
AbstractDue to the high volume of crude oil released by the Deepwater Horizon oil spill, the salt marshes along the gulf coast were contaminated with crude oil. Biodegradation of crude oil in salt marshes is primarily limited by oxygen availability due to the high organic carbon content of the soil, high flux rate of S2-, and saturated conditions. Chlorate, nitrate, and perchlorate were evaluated for use as electron acceptors in comparison to oxygen by comparing oil transformation and mineralization in mesocosms consisting of oiled salt marsh sediment from an area impacted by the BP Horizon oil spill. Mineralization rates were determined by measuring CO2 production and delta C-13 of the produced CO2 and compared to transformation evaluated by measuring the alkane/hopane ratios over a 4-month period. Total alkane/hopane ratios decreased (similar to 55-70 %) for all treatments in the following relative order: aerated approximate to chlorate > nitrate > perchlorate. Total CO2 produced was similar between treatments ranging from 550-700 mg CO2-C. The delta C-13-CO2 values generally ranged between the indigenous carbon and oil values (-17 and -27%, respectively). Oil mineralization was greatest for the aerated treatments and least for the perchlorate amended. Our results indicate that chlorate has a similar potential as oxygen to support oil mineralization in contaminated salt marshes, but nitrate and perchlorate were less effective. The use of chlorate as a means to promote oil mineralization in situ may be a promising means to remediate contaminated salt marshes while preventing unwanted secondary impacts related to nutrient management as in the case of nitrate amendments.