Abstract
The dinitrotoluene isomers 2,4 and 2,6-dinitrotoluene (DNT) represent highly toxic, mutagenic, and carcinogenic compounds used in explosive manufacturing and in commercial production of polyurethane foam. Bioremediation, the use of microbes to degrade residual DNT in industry wastewaters, represents a promising, low cost and environmentally friendly alternative technology to landfilling. In the present study, the effect of different bioremediation strategies on the degradation of DNT in a microcosm-based study was evaluated. Biostimulation of the indigenous microbial community with sulphur phosphate (2.3 g/kg sludge) enhanced DNT transformation (82% transformation, from 300 g/L at Day 0 to 55 g/L in week 6) compared to natural attenuation over the same period at 25 °C. The indigenous microbial activity was found to be capable of transforming the contaminant, with around 70% transformation of DNT occurring over the microcosm study. 16S rDNA sequence analysis revealed that while the original bacterial community was dominated by Gammaproteobacteria (30%), the addition of sulphur phosphate significantly increased the abundance of Betaproteobacteria by the end of the biostimulation treatment, with the bacterial community dominated by Burkholderia (46%) followed by Rhodanobacter, Acidovorax and Pseudomonas. In summary, the results suggest biostimulation as a treatment choice for the remediation of dinitrotoluenes and explosives waste.
Highlights
IntroductionExplosives are a global term that refers to specific energetic materials containing energy stored (e.g., trinitrotoluene, TNT) in one form or another (chemical, nuclear or pressurised gas) that can readily be exploded
Explosives are a global term that refers to specific energetic materials containing energy stored in one form or another that can readily be exploded
The results indicated that total bacterial numbers increased in each of the treatments compared to the control; for the bioaugmentation treatment, this resulted in a 40-fold increase
Summary
Explosives are a global term that refers to specific energetic materials containing energy stored (e.g., trinitrotoluene, TNT) in one form or another (chemical, nuclear or pressurised gas) that can readily be exploded. Explosive materials are required for a wide range of applications, including mining, construction, quarrying, space exploration and rockets, missiles and gun propellants [1]. In Germany, 2340 sites are listed as contaminated with residues of explosives [2]. Nitroaromatic compounds, such as TNT, are recalcitrant and persist in the environment (as a liquid or solid) for years; aerobic biodegradation is prevented due to the compounds electron-withdrawing characteristic resulting from the presence of multiple nitro groups (-NO2 ). Explosive materials (such as TNT and DNTs) can cause adverse health, ecotoxicological, cytotoxic, teratogenic and carcinogenic effects on a wide range of ecological receptors including microorganisms, algae, invertebrates, animals, 4.0/)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
