Journal of Forensic Pathology

Using Compost, Effective Bioremediation of Soil from the Burgan Oil Field in Kuwait was Studied thoroughly for Hydrocarbons and DNA Fingerprints

Jyoti Kumari^{* *}Correspondence: Jyoti Kumari, Department of Forensic, India, Email:

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Introduction

Petroleum hydrocarbons can pollute the environment in a number of ways, including spills and the use of petroleum-based products. In this regard, Kuwait likely experienced the largest oil spill on record during the Gulf War in 1991. In addition to the creation of several oil lakes and the partial volatilization of light chemicals, this spill seriously harmed the ecosystem. Large black smoke plumes were also produced by the oil field fires, and these finally settled as soot, tar mats and tarcrete deposits. The Greater Burgan field, the largest clastic oil field in the world with an area of 838 km2, is situated in southeast Kuwait and was one of the key locations impacted by this environmental catastrophe. The kind and concentration of oil fractions and other components involved, the qualities of the soil, the amount of time available for remediation measures, and the cost all play a role in the remediation technology that is chosen to address soil contamination by hydrocarbons. In this case, bioremediation may be the best course of action because of its low energy requirements, minimal danger of pollutant migration and secondary environmental effects, and cost-effectiveness. In fact, a wide variety of microbes have learned to utilize aliphatic and aromatic hydrocarbons as a source of carbon and energy. As a result, biodegradation can be enhanced by enhancing natural microbial populations or by introducing exogenous ones (bio augmentation). Aerobic bio stimulation techniques have frequently been used in effective bioremediation procedures, including the cleanup of significant oil spills on land and at sea. . On the other hand, exogenous microorganism-based bio augmentation strategies frequently raise a variety of problems. In this perspective, using compost for biostimulation in biopiles/windrows and land farming is an intriguing possibility. Kirchmann and Ewnetu gave specific examples of biopiles that had been composted in order to breakdown two different kinds of oil waste, namely oil sludge from petrol stations and oil wastes from refineries. In response, Fountoulakis et al. composted green waste and sludge from an oil refinery and saw an 85% reduction in PAHs in just 130 days. Sayara et al. virtually completely degraded pyrene in a short amount of time using compost as an amendment and pyrene as a model pollutant. When Dados et al. compared compost bio stimulation to bio augmentation, they discovered that soils treated with compost had the fastest rates of deterioration. Overall, compost appears to concurrently increase the organic matter and nutritional content of soil, promote microbial activity, provide more microorganisms, and support circular economy strategies. Therefore, to assess these complex impacts, extensive chemical and microbiological research are needed. Different oil components are affected by biological processes differently. In this regard, a stage in which the hydrocarbon concentration typically is residual is typically followed by an early phase of far-reaching biodegradation. Indeed, bioavailability limits related to soil characteristics, microbial activity, and weathering processes influence the yields of biodegradation. Advanced analytics should be used to address the fate of oil components in light of these factors. To discriminate between biotic and abiotic processes, for instance, accurate diagnostic ratios are needed. Gas Chromatography-Mass Spectrometry (GC-MS) is therefore necessary for a thorough study of pollutant fingerprinting. Although it has been claimed that asphaltenes and other heavy oil fractions may degrade, little is known about their destiny in this situation. As shown in numerous environmental studies, analytical Pyrolysis-Gas Chromatography-Mass Spectrometry (Py-GC-MS) is an appropriate method for studying heavy fractions. This strategy can also be used with Thermodesorption (TD) methods to offer a quick method for screening fingerprints. Next-Generation Sequencing (NGS), albeit still costly and time-consuming, has recently shown to be helpful in microbial investigations for examining the topologies of microbial communities. Instead, sophisticated and quick technologies called molecular fingerprinting techniques can be employed to calculate the diversity and dynamics of microbial community structures. They are unable to offer taxonomic information though. The molecular fingerprinting technique called Automated Ribosomal Intergenic Spacer Analysis (ARISA) was created by Fisher and Triplett. The bacterial 16–23 S rRNA hypervariable intergenic spacer region is amplified by PCR in ARISA. ARISA enables the acquisition of a community-specific banding pattern due to the heterogeneous length of this region. In our setting, ARISA offers a quick and economical way to evaluate bacterial community structures and determine how environmental conditions affect them. In accordance with all of the foregoing, we used microcosm experiments to investigate the efficacy of compost as the primary ingredient for the rehabilitation of soil damaged by an oil spill in Kuwait's Burgan field. We not only addressed the history of the concentration of total hydrocarbons but also identified the fractions that underwent the most biodegradation and could therefore be regarded truly resistant using thorough GC-MS fingerprinting. The variations in the heavy fractions were also investigated using gravimetric measurements and PyGC-MS analysis. Additionally, we conducted a microbiological investigation utilising ARISA that was centred on the DNA fingerprinting of microbial populations, allowing us to deduce the functions of bacterial populations in compost biostimulation. By combining these two rapid molecular fingerprinting methods (chemical and microbiological), we were able to predict the evolution of microbial populations and hydrocarbon families in Kuwait's oil spill area, as well as draw conclusions about the value of compost in bioremediation. Based on our research, this dual approach is suggested as a novel method for tracking the progress of bioremediation. The samples included oiled sandy soil that had been marginally shielded from the impacts of weathering under extremely dry and noxious circumstances for years. They were taken in 2019 on one of the places (Burgan Field) where the first Gulf War's massive spills had an impact. A "dry oil lake" is where the samples came from. In this regard, the polluted sand was sampled from a depth of approximately 5 to 40 cm, but the soil was sealed by a tar mat that was about 1 cm thick and had to be scraped off in order to disclose the polluted sand beneath. Samples of air-dried soil were put through a 2 mm mesh screen. They were then homogenized and disaggregated using a roller. Gravel and pebbles were not included in the study, although material with a grain size more than 2 mm was washed and rubbed off to recover small particles. The DINO-LITE AM7915-MZT digital microscope was used to look at sand particles that had been coated with hydrocarbons. By quartering in a channel separator, several typical batches of the final fraction 2 mm were produced. The normal techniques were used to characterize these batches. Using a glass electrode, the pH was measured in a suspension of soil and water (1:2.5), and electrical conductivity was assessed in the same extract (diluted 1:5). The Olsen method was used to calculate the available phosphorus concentration, while the Kjeldahl method was employed to assess the nitrogen amount. The Loss on Ignition (LOI) method was used to calculate organic matter. Texture was identified using the Bouyoucos Densimetry technique. Total TOC-V CSH (Shimadzu) analyzers were used to measure TOC (Total Organic Carbon), IC (Inorganic Carbon), and Total N (LECO CN-200) respectively. For multielement analysis, 0.250-g representative subsamples were leached by means of a 'Aqua regia' digestion (HCl + HNO3) in an Anton Paar 3000 microwave, then passed through a 0.45-μm filter and diluted for the quantitative determination of major and trace elements by Inductively Coupled Plasma Mass Spectrometry (ICP-MS 7700, Agilent Technologies, California, USA) using IDA (Isotopic Dilution Analysis), with a spike solution from ISC Science, Spain. In a nutshell, the samples had characteristics of a desert environment, such as an alkaline pH, high salinity, sandy texture (less than 10% silt and clay), and extremely low quantities of nitrogen and phosphate. The C/N ratio consequently approached 100. The high level of organic matter was linked to the hydrocarbons' presence. We came to the conclusion that the samples consisted primarily of siliceous sand with small clayey and carbonate components because none of the inorganic elements tested had noteworthy quantities. These results also disregarded the possibility that bacteria that break down materials might be inhibited since no heavy metalloids were present in sufficient quantities to do so.