Petroleum hydrocarbons contamination of the environment associated with exploration, development and production operations is a common feature in oil producing nations around the world, especially in a developing country like Nigeria where the incidence of facilities sabotage, operational failures, accidental discharges, pipeline vandalization and leakages, bunkering and artisanal refining is very common. Apart from poor governance systems, poor corporate social responsibility (CSR) of multinational oil companies (MOCs), poor environmental regulation of the petroleum industry, the inability of the political elite to effectively manage petroleum hydrocarbon-derived revenue, loss of petroleum hydrocarbons resource revenue to corruption and theft, petroleum hydrocarbons contamination of the total environment (air, soil, water and biota) have impacted negatively on the human health and wellbeing of oil producing communities in the Nigeria's Niger Delta region. Findings from several studies have revealed variable negative impacts of petroleum hydrocarbons toxicity on the human health (including exposed populations), the natural environment and other ecological receptors. Over the past fifty-five years, the oil producing host communities in the Nigeria's Niger Delta region have experienced a wide range of environmental pollution, degradation, human health risks, deterioration of our cultural heritage items and socio-economic problems as a result of various activities associated with petroleum exploration, development and production. Petroleum hydrocarbons contamination of surface water and groundwater is a notable environmental and human health problem in the oil producing communities and there are several water quality issues in the Nigeria's Niger Delta region. This review examines some of the water quality issues and human health implications of petroleum hydrocarbons contamination of controlled water sources (surface-water and groundwater) in the oil producing host communities in the Nigeria's Niger Delta region. It will further highlight some of the problems of petroleum hydrocarbons contamination and/or pollution of marine environments associated with unsustainable practices of petroleum industry in the region.

This study was carried out to assess indoor air quality (IAQ) in schools in Akwa Ibom State of Nigeria during the rainy (June-July) and dry (November-December) seasons of 2018. IAQ parameters were examined to assess pollutant levels in schools within Akwa Ibom State in single setting only (naturally ventilated classrooms). Schools were randomly selected from two zones: zone 1 which is located within the Capital City (Uyo metropolis) and represents the 'urban sector', and zone 2 which is located within the southern part of the state in close proximity to the oil and gas industrial region and represents the 'industrial sector'. Indoor air investigation included the following parameters: particulate matter (PM 1 , PM 2 , PM 5 , and PM 10), carbon monoxide (CO), carbon dioxide (CO 2) levels, temperature and relative humidity, which were simultaneously measured in fourteen (14) sampling days using Fluke 985 Particle Counter and Fluke 975 AirMeter. Multiple statistically analysis techniques were used to compare IAQ parameters and test for significant differences between the zones (urban vs. industrial) and annual seasonal variations. The concentrations of particulate matter (PM) in the naturally ventilated classroom in industrial zone during the rainy season ranged from 5152-5984 μg/m 3 for PM 1 ; 2744-3207 μg/m 3 for PM 2 ; 137-149 μg/m 3 for PM 5 ; 38-46 μg/m 3 for PM 10 and in urban zone, the concentrations of PM ranged from 1978-2491 μg/m 3 for PM 1 ; 1010-1311 μg/m 3 for PM 2 ; 38-56 μg/m 3 for PM 5 ; 15-24 μg/m 3 for PM 10. During the dry season, the concentrations of PM in the naturally ventilated classroom in industrial zone ranged from 6138-6999 μg/m 3 for PM 1 ; 2984-3980 μg/m 3 for PM 2 ; 146-159 μg/m 3 for PM 5 ; 47-59 μg/m 3 for PM 10 and in urban zone, the concentrations of PM ranged from 2556-3972 μg/m 3 for PM 1 ; 1911-2311 μg/m 3 for PM 2 ; 51-66 μg/m 3 for PM 5 ; 18-34 μg/m 3 for PM 10. Results of this study has revealed that the concentrations of PM 1 , PM 2 , PM 5 , and PM 10 measured in the naturally ventilated classroom in industrial zone were significantly (p < 0.001) higher than those measured in the urban zone during both rainy and dry seasons. In this present study, the concentrations of PM 10 measured were found to be much lower than the ambient maximum contaminant level for airborne PM 10 standard promulgated by the United States Environmental Protection Agency (US-EPA) (150 μg/m 3 daily average and 50 μg/m 3 annual average) and World Health Organization (WHO) PM 10 guidelines values (50 μg/m 3 daily average and 20 μg/m 3 annual average). Apart from re-suspension of atmospheric particles, anthropogenic activities in industrial zone significantly influenced the measured concentrations of PM compared to those measured in urban zone. In addition, the lower concentration of CO and CO 2 measured indicated adequate air exchange at the time of the assessment in the naturally ventilated classrooms during the sampling period. The results obtained reveal important contributions towards understanding o...

The use of environmentally benign materials as adsorbent for bleaching palm oil has been revitalize due to loss of significant amount of oil associated with commercial bleaching earth. This paper examined the performance of inactivated shell samples from snail, mussel, periwinkle and the corresponding acid activated samples as an alternative bleaching material for palm oil. Effectiveness of the bleaching process was examined by determining critical process parameters such as degree of bleaching (%), adsorbent dosage (%), and oil retention capacity of the adsorbent. Maximum bleaching performance of 98.70%–96.60% for inactivated samples and 97.79%–95.52% for 0.5 M hydrochloric acid activated samples were obtained at low adsorbent dosage of 9.09 wt.%. The weight percentage of residual oil (1.38–20.08 wt.%) in the spent adsorbent was extremely low for all the samples. Inactivated samples could be a better alternative for commercial adsorbent.

The study evaluates the heavy metals, geo-accumulation index and contamination factor in soil around dumpsites in Uyo, Akwa Ibom State, Nigeria. Soil samples were collected, during rainy season, at depth of 0-15cm and 15-30cm from two study sites (A, B) and a control site (C). Soil samples were all analyzed for heavy metals (Pb, Ni, Cd and Cu) using Atomic Absorption Spectroscopy (AAS). The concentration of Lead at site A for depth 0-15 cm ranged from 13.71 -14.90 mg/kg with a mean value of 14.38 ± 0.61 mg/kg; Nickel varied from 2.35 – 3.22 mg/kg (2.74 ± 0.44 mg/kg); Cadmium ranged from 3.78 – 4.13 mg/kg (3.93 ± 1.18 mg/kg); Copper ranged from 27.84 – 28.34 mg/kg (28.14 ± 0.27 mg/kg). The heavy metals concentration in soil at sites A and B followed the sequence, Cu > Pb > Cd > Ni while at the control site; Cu > Cd > Ni > Pb. The calculated geo-accumulation index (Igeo) showed that the soil samples from sites A and B for Pb, Ni and Cu belong to class 2, which implies that the soil was moderately contaminated. The Igeo values for Cd at sites A and B were classified as 4, indicating a strongly contaminated soil. However, Igeo of Cd at the control site is class 3, implying moderately to strongly contaminated soil. Calculated contamination factor (CF) showed that Pb, Ni and Cu for sites A, B and control at depths 0-15cm were in class 1 (low contamination), while Cd contamination was class 4 except at control site (15 -30cm) which showed CF of class 3.  The contamination degrees (CD) for the sampling sites A and B showed considerable contamination and their pollution load index (PLI) indicated a progressive deterioration of the sites; however, the control site recorded very minimal state of pollution. Generally, the results found that the top soil (0 – 15 cm) was more contaminated than the sub soil (15 – 30 cm) of all sample sites studied. The results of this study imply that the inhabitants around Sites A and B are exposed to Cadmium pollution and the soil is not suitable for agricultural practice, since plants can take up these toxic metals and bio-accumulate them in their tissues. Cadmium, at high concentration in plants, can cause serious clinical and physiological effects on humans when consumed as food.

Nanoremediation approaches have been applied to remove oil from surface and ground water as oil spills have been found to have long-term negative consequences for the ecosystem. Nanoremediation via the nanosorption mechanism of different environmental matrices in the world at large is at its formative stages despite the alarming and extensive prevalence of petroleum related environmental pollution. Over 9 million barrels of oil have been leaked in the last five decades, making that ecosystem one of the most deteriorated by oil exploration and extraction activities. The goal of this research is to assess the current status, trends, and future prospects of the nanosorption of surface and ground water in oil spill regions. High surface area of nanomaterials, wide spectrum of treatable contaminants, non-generation of intermediate or secondary products, as well as speed and extent of contaminant destruction give nanoremediation a superior comparative edge over other treatment technologies. Notably, the remediation efficiency of a cleanup is highly dependent on the type of material and treatment routes employed. It is imperative to employ a concerted and practical approach to the development of nanotechnology to combat the bedeviling oil pollution challenges faced in oil producing counties.

Cocosnucifera (coconut) shell powder was used as the adsorbents for the removal of phenol from aqueous solutions. Degradation efficiency has been evaluated using photocatalysis and adsorption processes at ambient temperature. Photolysis was performed to study the effect of light on the degradation of phenol at ambient temperature while adsorption process was carried out without utilizing solar illumination. Effect of initial concentrations of phenol (50, 75, 100 and 150 mg/l), TiO2 loading (4, 8, 16 and 20 %), and composite mass (adsorbent + TiO2) (1, 3, 5 and 8 g) were investigated using UV-Visible spectrophotometric technique. The results obtained indicate that phenol removal increases with time and concentration of the catalyst (TiO2) and decreases with increase in initial concentration of phenol and composite mass. Combination of UV irradiation with TiO2 loading gave a degradation efficiency ranging from 78.36-82.76 % while UV irradiation with composite (catalyst-Cocosnucifera) mass gave a degradation efficiency ranging from 63.12-79.32 %. The efficiency of the processes of degradation of phenol followed the trend: photocatalysis>photolysis> adsorption. The kinetics studies of the degradation fitted the Langmuir and pseudo-second-order models.

The atmospheric corrosion of Calabar, Cross River State environment has been investigated for 12 months using weight loss technique. The extent of pollution of the environment was also determined via measurements of the precipitation and air quality parameters. Apart from the suspended particulate matter (SPM) (113-630 μg/m 3 ) and NO 2 (> 0.06 ppm) values, other measured atmospheric parameters (CO < 9.2 ppm, NH 3 < 4.3 ppm and SO 2 < 0.380 ppm) and precipitation parameters (pH > 5.0, conductivity < 60 µScm -1 , TDS < 41.48 mg/l, TSS < 0.05 mg/l, NO 3 -< 3.00 mg/l, SO 4 2-<1.00 mg/l and NH 4 + <1.00 mg/l) indicate that the environment has received little or no detrimental influence by human activities. The average corrosion rates for all the stations studied were below 35 μm/yr, and are due principally to natural phenomenon (high rainfall, humidity and temperature).

Indoor air quality parameters were investigated in an occupied air-conditioned office and unoccupied air-conditioned office located in the Faculty of Natural and Applied Sciences Complex in Akwa Ibom State University -Nigeria, during the rainy (June -July) and dry (November -December) seasons of 2016. Particulate matter (PM 1 , PM 2 , PM 5 , PM 10 ), temperature, relative humidity, carbon monoxide (CO) and carbon dioxide (CO 2 ) levels were simultaneously measured in fourteen (14) 10 . This study has revealed that the particulate matter (PM 1 , PM 2 , PM 5 , PM 10 ) concentrations in an occupied air-conditioned office were significantly (P < 0.001) higher than those obtained in unoccupied air-conditioned office during both rainy and dry seasons. However, the concentrations of PM 10 obtained in the present study were found to be much lower than the ambient maximum contaminant level for airborne PM 10 standard promulgated by the United States Environmental Protection Agency (USEPA) (150 μg/m 3 daily average and 50 μg/m 3 annual average) and World Health Organization (WHO) PM 10 guidelines values (50 μg/m 3 daily average and 20 μg/m 3 annual average). Although there were no significant relationships among PM 1 , PM 2 , PM 5 , and PM 10 in occupied air-conditioned office, correlation analysis indicated that PM 1 , PM 2 and PM 5 were significantly correlated at P < 0.01 in unoccupied air-conditioned office and correlation coefficients were different. Apart from suspended atmospheric dust and settling dust, human activities in the occupied air-conditioned office significantly influenced the particulate matter concentrations obtained compared to those obtained in unoccupied air-conditioned office in both rainy and dry seasons. Although the concentrations of CO and CO 2 were below detection limit (BDL), they indicated adequate air exchange at the time of the assessment in the air-conditioned office during the sampling period. The results obtained have revealed important contributions towards the understanding of particulate matter distribution patterns and provided baseline data that can be used for potential identification of human health risks associated with airborne particulate matter in air-conditioned offices in Akwa Ibom State University -Nigeria. Keywords