12,000

We have over 12,000 students, from over 100 countries, within one of the safest campuses in the UK

93%

93% of Lancaster students go into work or further study within six months of graduating

Home > Research > Publications & Outputs > Impact of black carbon in the extraction and mi...
View graph of relations

« Back

Impact of black carbon in the extraction and mineralization of phenanthrene in soil.

Research output: Contribution to journalJournal article

Published

Journal publication date02/2008
JournalEnvironmental Science and Technology
Journal number3
Volume42
Number of pages6
Pages740-745
Original languageEnglish

Abstract

During the past century, increased biomass burning and fossil fuel consumption have drastically increased the input of black carbon (BC) into the environment, and that has been shown to influence the behavior of organic contaminants in soil. A study was conducted to investigate the effects of BC on the relationship between aqueous hydroxypropyl-beta-cyclodextrin (HPCD) extraction and microbial mineralization (bioaccessibility) of C-14-phenanthrene (10 mg kg(-1)) in four soils amended with 0, 0.1, 0.5, 1, 2.5, and 5% (% dry wt soil) activated charcoal, a type of BC. Mineralisation was monitored over 20 d incubation, within respirometric assays, using an inoculum containing a phenanthrene-degrading pseudomonad and compared to HPCD extraction (24 h) using 50 mM aqueous solution; analyses were conducted after 1, 25, 50, and 100 d soil-phenanthrene contact time. Statistical analyses revealed that for each soil the addition of BC led to significant (P < 0.001) reductions in both HPCD extractability and microbial mineralization. Linear correlations for BC concentrations of 0% (r(2) = 0.95; slope = 0.89) and 0.1% (r(2) = 0.67; slope = 0.95) revealed a highly significant (P < 0.01) relationship between HPCD extractability and total mineralization (20 d), indicating a direct prediction of phenanthrene bioaccessibility by HPCD. However, in soils amended with 0.5, 1, 2.5, and 5% BC exhibited r(2) values ranging 0.51-0.13 and slopes of 2.19-12.73. This study has shown that BC strongly sorbs phenanthrene causing reductions in extractability and,to a lesser extent, bioaccessibility to degrading microorganisms.