Bioremediation Assessment of a BTEX‐Contaminated Soil

Abstract

SummaryThe elimination of BTEX (benzene, toluene, ethylbenzene, o-xylene) compounds from soil was studied. After 18 days at 20°C, 21% of the initial total BTEX contamination (400 mg/kg soil) was lost due to sorption onto soil. Biodegradation decreased in the order ethylbenzene > toluene > benzene > o-xylene. NPK fertilisation stimulated biodegradation, particularly that of benzene and toluene, significantly, and oleophilic fertilisation inhibited biodegradation. After 18 days, the residual contamination in the NPK-fertilised, unfertilised and with oleophilic nutrients amended soil was 96, 166 and 196 mg total BTEX/kg soil, respectively. The presence of BTEX initially inhibited the biological activity of the soil (fluorescein diacetate hydrolysis) considerably. This short-term, reversible inhibition was significantly higher in the unfertilised soil than in the fertilised soil.

Review: <i>BTEX compounds in water – future trends and directions for water treatment</i>

“…The study highlighted that the most abundant hydrocarbons present in the water were BTEX compounds (up to78 µg/L). These findings have been reiterated in various studies, such as Essaid et al (2003), Margesin et al (2003), and Das and Chandran (2011).…”

“…Bioremediation has gained a lot of research momentum due to the belief that it does not result in any undesirable consequences after the remediation process has been completed (Bowlen et al, 1995;Lovley, 1997;Chapelle, 1999;Margesin et al, 2003;Andreoni and Gianfreda, 2007). The ability of microbes to remediate BTEX compounds is dependent on their Drinking water < 0.1 -5 < 1 -27 < 1 -10 < 0.1 -12…”

“…The ability to degrade highly toxic pollutants such as BTEX compounds is occasionally dependent on the microbes' ability to produce secondary metabolites such as biosurfactants (Chirwa et al 2013). This has been reiterated by Margesin et al (2003) and Lu et al (2006), where synthesis of rhamnolipid biosurfactants has been reported to aid the uptake and degradation of BTEX compounds. The effective uptake and degradation of BTEX compounds, however, is due to certain environmental conditions, with some beneficial to the process, while others seem to impede it.…”

Remediating polluted soils

“…Margesin et al 2003), several studies (e.g. Sarkar et al 2005) have found that treatment rates converge with time, with no marked improvement in overall treatment outcome compared with natural attenuation.…”

Biodiversidad de actinomicetos aislados de plantas depuradoras de aguas residuales. Estudio de la capacidad de biodegradación de compuestos tóxicos

“…Su alto grado de solubilidad contribuye a su movilidad, permitiéndoles migrar al subsuelo y contaminar aguas subterráneas que abastecen a los seres humanos y a los animales (Margesin et al, 2003).…”