Characterization of Petroleum Hydrocarbons in Post-Burn Crude Oil-Spilled Soils, Gokana, Rivers State, Nigeria

In the Niger delta, crude oil spilled soils are burned as a means of decontaminating the impacted soils. Gas chromatography - flame ionization detector (GCFID) analyses were performed on oil residues extracted from burnt spilled oil soil samples to facilitate detailed chemical composition and characterization of petroleum hydrocarbons. The concentrations of aliphatic hydrocarbons (AHCs) from C13 to C36 were low and range from 363.4 to 439.6 mg/kg, with hydrocarbons burning ≤ C12 and the monocyclic aromatics – BTEX not detected in all the samples. Polycyclic aromatic hydrocarbon (PAH) concentrations, which ranged from 3236.6 to 4190.0 mg/kg, were significantly high and constituted from 88.26 to 91.25% of total petroleum hydrocarbon compositions in the burnt spilled oil soil samples. Petroleum hydrocarbon distribution profiles for the AHCs and PAHs were similar for all the samples and indicated similar alteration source. The compositions of AHCs were generally low, between 1.13 and 11.18%, while compositions of PAHs varied considerably from 0.17 to 30.50%. The composition of the 5-6 ring PAHs were between 3.94 - 4.65 times more than the 2-4 ring PAHs. From these results, the burning of spilled oil soils extensively degraded the AHCs and volatile low molecular weight aromatic hydrocarbons and generated significant amounts of 5-6 ring PAHs, some of which are carcinogenic

Occurrence and sources of aliphatic hydrocarbons in soils within the vicinity of hot mix asphalt plants in Obigbo and Igwuruta Areas of Rivers State, Nigeria

This study investigated the occurrence and sources of aliphatic hydrocarbons (AHCs) in soils within the vicinity of hot mix asphalt (HMA) plants. Soil samples were collected from two HMA plants and analysed with gas chromatography - flame ionisation detector (GC-FID). Sample collection was from both surface (0-15 cm) and subsurface (15-30 cm) soils at an increasing distance of 10 m from the HMA plants while the control samples at both depths were collected at 1 km away from the plants. The AHCs concentration (nC9-nC38) in soils from both HMA Plants ranged from 8.16 - 433.04 mg/kg and 5.91-177.83 mg/kg for surface and  subsurface soils respectively while the concentration in the control samples ranged from 5.97 - 23.95 mg/kg and 2.52 - 13.31 for surface and subsurface soil respectively. The sources of the AHCs were determined using isoprenoid ratios, carbon preference index (CPI) and maximum carbon chain (Cmax). The isoprenoid ratios and CPI values of the samples closer (< 20 m) to the HMA plants were < 1 and < 2 respectively indicating anthropogenic inputs. Samples > 20 m from the HMA plants showed mixture of both anthropogenic and biogenic sources.Keywords: Asphalt Plants; Soil; Aliphatic hydrocarbons; Pristane; Phytane

Distribution of Polycyclic Aromatic Hydrocarbons in Soils within Vicinity of an Electronic Waste Open Burning Workshop in Aba, South East Nigeria

Electronic waste (e-waste) workshops distributed in the commercial city of Aba, South East Nigeria, employ open burning to extract valuable sub-assemblies from the e-waste. Polycyclic aromatic hydrocarbons (PAHs) were studied in soils (0-5 cm) collected from three sampling points within an e-waste workshop vicinity: the e-waste open burning site (OBS-X), 30 m from the open burning site (OBS-30m) and 70 m from the open burning site (OBS-70m). Concentrations of 16 USEPA PAHs in the soils were characterized by dominance of high molecular weight (HMW) over low molecular weight (LMW). The most abundant PAHs were DA 26.45%, IP 13.82% and BbF 13.07% in OBS-X, BaA 19.78%, BbF 17.15% and BaP 16.80% in OBS-30m and Chr 23.73%, BP 14.26% and Nap 8.871% in OBS-70m. Source diagnostic PAH isomer ratios determined are Phe/Ant from 0.73 - 1.36, Fth/Pyr 1.52 - 3.79, BaA/Chr 0.29 - 28.27 and BkF/BaP 0.11 - 1.31. These results from PAH distributions and compositions indicated incomplete combustion source for pyrogenic PAHs in OBS-X and OBS-30m and mix combustion-petroleum source for PAHs in OBS-70m. In conclusion, the open burning of e-waste in Aba metropolis largely contaminated soils from the workshop vicinity, particularly with carcinogenic HMW PAHs

Source Apportionment of Polycyclic Aromatic Hydrocarbons in Indoor Fine Dusts from Residential and Public Buildings in Port Harcourt, Rivers State, Nigeria

The sources of polycyclic aromatic hydrocarbons in indoor fine dust from residential and public buildings in Port Harcourt, Rivers State, Nigeria was investigated using source apportionment tools such as diagnostic/isomeric ratios, principal component analysis (PCA) and hierarchical cluster analysis (HCA). A total of twenty-seven indoor fine dusts comprising of twenty samples from residential building and seven samples from public buildings were collected from Port Harcourt. The PAHs in the dust samples were quantified by gas chromatograph equipped with mass spectrometry (GC-MS) after extraction by ultra-sonication with hexane/dichloromethane/acetone and cleaned up   on a silica gel/alumina column. The Σ16 PAH concentrations in the indoor fine dusts ranged from 3136 µg kg-1 to 44332 µg kg-1 for residential buildings and 2580 µg kg-1 to 15372 µg kg-1 for public buildings. The results of source apportionment indicated that the PAHs in the indoor fine dusts were from mixed sources pyrogenic sources (coal, wood, petroleum, biomass, and fossil fuel combustion) and petrogenic sources with significant contribution from pyrogenic sources

Behavioural characteristics of adulterated Premium Motor Spirit (PMS)

Distillation profiles and chemical characteristics of ten suspected adulterated Premium Motor Spirit samples randomly collected from different dispensing points were analysed to determine the chemical characteristics of these samples when compared to a reference sample that is not adulterated. Results of the analyses show, Research Octane Number values ranged from 60.10 to 93.30, specific gravity ranged from 0.75 to 0.79, Reid Vapour Pressure ranged from 0.28 kgf/cm2 to 0.60 kgf/cm2 while Atmospheric distillation ranged from 189 to 251 °C. The results of this research reveal that most of the products are highly adulterated and may pose problems when sent to the market for intended end users

Genotoxicity Of Petroleum Refinery Waste Water In Nigeria

The genotoxicity of petroleum refinery wastewater was investigated with the Allium test. 10 medium – sized Allium cepa L. bulbs of the pink variety were induced to sprout roots in distilled water and variously assaulted for 48 hours with different concentrations (v/v) of wastewater from the refinery. Serial dilutions of 20%, 40%. 60%, 80% and 100% were used while distilled water served as control. After the assault, roots were harvested from each treatment sample and assayed for genotoxic effects with the acetocarmine squash technique. Results showed that the wastewater induced statistically highly significant (P ≤ 0.001) mitodepressive effects which were dose-dependent, culminating in total mitotic inhibition at 100% v/v concentration. Other aberrations including stickiness of chromosomes, erosion of chromatin, vagrant chromosomes, fragments and anaphase bridges were induced at higher concentrations (60%-80%) of wastewater. Lower concentrations (20%-40%) induced c-mitosis as the major aberration. The advantages of genotoxicity screening over general toxicity testing in environmental monitoring was highlighted. Key Words: Allium test, pollution, genotoxicity, chromosome, wastewater. Global Journal of Environmental Sciences Vol.3(1&2) 2004: 55-5

Source identification of polycyclic aromatic hydrocarbons in sediments of a creek around a flow station

Sources of the sixteen polycyclic aromatic hydrocarbons (PAHs) in the United States Environmental Protection Agency priority pollutants list were determined in sediments of Kolo Creek using diagnostic ratios of parent PAHs[phenanthrene/phenanthrene + anthracene; fluoranthene/fluoranthene + pyrene; benz(a) anthracene/benz(a) anthracene + chrysene and indeno(1,2,3-d)pyrene/indeno(1,2,3-cd)pyrene + benzo(ghi)pyrelene]. The study was conducted over four seasons (dry, late dry, rainy and late rainy seasons). Applying cross plots of the diagnostic ratios revealed that PAHs in Kolo Creek sediment have pyrogenic origins except in the rainy season that had petrogenic origins. Comparison of diagnostic ratio values obtained from this study with literature values enabled the further classification into types of pyrogenic and/or petrogenic sources. While the pyrogenic sources of PAHs were mainly as a result of Grass/Wood combustion, the petrogenic PAHs were as result of drained diesel and lubricating oil. The predicted sources corresponded with the prevailing human activities in the vicinity, especially samples collected near a petrol station and an abattoir. This study further affirms the simplicity and accuracy of the use of diagnostic ratios for PAHs source prediction

Preliminary hydrocarbon analysis of crude oils from Umutu/Bomu fields, south west Niger Delta Nigeria

Seven different crude oil samples were collected from two oil fields in the Niger Delta Nigeria. The bulk properties of these crude oils which include API gravity, reid vapour pressure; kinematic viscosity, dynamic viscosity, moisture, gum content and cloud point were analysed. Aliphatic biomarkers were used as supporting tool to deduce the geochemical characteristics such as thermal maturity, depositional environments, source of organic matter and extent of biodegradation. Results show that API° gravity ranged from 29.00° to 85.00°, specific gravity 0.65 to 0.88, 3.00 to 9.00, reid vapour pressure 3.00 to 9.00 kPa, kinematic viscosity 0.90 to 10.10 cSt, dynamic viscosity 0.70 to 8.90 cP, moisture content 0.13% to 26.00%, gum content 6.27 to 45.84 mg/L, cloud point 3.00 to 12.00 °C, pour point −7.00 to 4.00 °C and flash point <30.00 °C. Distribution of n-alkanes (Pr/Ph, and isoprenoide/n-alkanes ratios) reflects that the oil samples originated mainly from terrestrial organic sources deposited in an oxic paleoenvironment

Geochemical Evaluation of the Source of Mystery Oil Spill Impacted at Imo-River, Niger Delta, Nigeria

Abstract Sediment samples contaminated with mystery oil spills at the Imo-River (South East, Nigeria