Impact of soil organic matter on groundwater contamination risks for ethanol and butanol blended gasoline

This work examined the impact of soil organic matter (SOM) on the sorption, phase distribution and transport of ethanol and butanol blended gasoline vapours after release. Microcosm and mini-lysimeter experiments were conducted using sand with varying SOM and moisture contents. Synthetic gasoline alone and blended with 10 - 20% ethanol and 10 - 20% butanol by volume, referred to as UG, E10 - E20 and B10 - B20, respectively, were used. Results from the UG were used as the benchmark to assess the impact of ethanol and butanol on gasoline compounds. The findings of this work illustrate the likely behaviour of gasoline compounds at the beginning times of a gasoline spill or leak. The addition of alcohol to gasoline altered the behaviour of the gasoline compounds in the vadose zone in several ways. Firstly, it reduced the sorption of the gasoline compounds by soils. This effect was greatest on the first day of a spill and affected the gasoline compounds in decreasing order of hydrophobicity. Secondly, it altered the mass distribution of the gasoline compounds between the vadose zone phases to higher mass compounds in the mobile phases (soil air and soil water) and lower mass compounds in the immobile soil solid phase, suggesting higher risk of groundwater contamination with an increasing content of alcohol in the gasoline. Thirdly, it increased the vapour phase transport of the gasoline compounds from the source zone to the groundwater zone. These three impacts were generally greater for ethanol than butanol. The sorption coefficients (Kd) of E20 gasoline compounds were reduced by 54% for alkanes, 54% for cycloalkanes and 63% for the aromatics, while the Kd of B20 gasoline compounds decreased by 39% for alkanes, 38% for cycloalkanes and 49% for aromatics. This implies that the use of ethanol as gasoline oxygenate could result in greater risk of groundwater contamination with gasoline compounds than the use of butanol after spills. The SOM enhanced the sorption of alcohol-blended gasoline compounds in soils. This impact was similar for ethanol and butanol blended gasoline as the Kd of B20 and E20 were equally increased by 7 times for aromatics, 4 times for cycloalkanes and 2 times for alkanes, for 0 to 5% increase in the SOM fraction of sand. Although SOM enhanced the sorption of alcohol-blended gasoline, its sorptive capability was not fully realised compared with the sorption of the UG compounds. Also, it did not alter the order of groundwater contamination risk for the ethanol and butanol blended gasoline. Thus, the Kd values for all gasoline compounds for all the SOM fractions tested, including 0%fom, 1%fom, 3%fom and 5%fom, were in the order of UG>B20>E20, indicating greater risk of groundwater contamination for the ethanol-blended gasoline after a spill or leak regardless of the SOM content of the soil. The increase in the water content of soil reduced the sorptive capability of SOM and affected the overall mass distribution of gasoline compounds between the soil solid, soil air and soil water phases estimated with values of Henry’s law constant from the literature. This indicates that the degree of gasoline retention in the vadose zone by SOM could differ during the dry summer and wet winter seasons. This effect was greater for ethanol than butanol. Thus, in all seasons, the amount of gasoline compounds retained by SOM in the vadose zone is likely to be higher for butanol-blended gasoline than ethanol-blended gasoline. Overall, this study indicates that the use of high ethanol volume in gasoline to combat climate change may put the groundwater at greater risk of contamination after spills or leakages from storage. Therefore, to successfully reduce greenhouse gases emissions via high alcohol volume in gasoline and still protect the world’s groundwater resource, this study suggests the use of butanol is more benign than ethanol

Impact of soil organic matter on groundwater contamination risks for ethanol and butanol blended gasoline

This work examined the impact of soil organic matter (SOM) on the sorption, phase distribution and transport of ethanol and butanol blended gasoline vapours after release. Microcosm and mini-lysimeter experiments were conducted using sand with varying SOM and moisture contents. Synthetic gasoline alone and blended with 10 - 20% ethanol and 10 - 20% butanol by volume, referred to as UG, E10 - E20 and B10 - B20, respectively, were used. Results from the UG were used as the benchmark to assess the impact of ethanol and butanol on gasoline compounds. The findings of this work illustrate the likely behaviour of gasoline compounds at the beginning times of a gasoline spill or leak. The addition of alcohol to gasoline altered the behaviour of the gasoline compounds in the vadose zone in several ways. Firstly, it reduced the sorption of the gasoline compounds by soils. This effect was greatest on the first day of a spill and affected the gasoline compounds in decreasing order of hydrophobicity. Secondly, it altered the mass distribution of the gasoline compounds between the vadose zone phases to higher mass compounds in the mobile phases (soil air and soil water) and lower mass compounds in the immobile soil solid phase, suggesting higher risk of groundwater contamination with an increasing content of alcohol in the gasoline. Thirdly, it increased the vapour phase transport of the gasoline compounds from the source zone to the groundwater zone. These three impacts were generally greater for ethanol than butanol. The sorption coefficients (Kd) of E20 gasoline compounds were reduced by 54% for alkanes, 54% for cycloalkanes and 63% for the aromatics, while the Kd of B20 gasoline compounds decreased by 39% for alkanes, 38% for cycloalkanes and 49% for aromatics. This implies that the use of ethanol as gasoline oxygenate could result in greater risk of groundwater contamination with gasoline compounds than the use of butanol after spills. The SOM enhanced the sorption of alcohol-blended gasoline compounds in soils. This impact was similar for ethanol and butanol blended gasoline as the Kd of B20 and E20 were equally increased by 7 times for aromatics, 4 times for cycloalkanes and 2 times for alkanes, for 0 to 5% increase in the SOM fraction of sand. Although SOM enhanced the sorption of alcohol-blended gasoline, its sorptive capability was not fully realised compared with the sorption of the UG compounds. Also, it did not alter the order of groundwater contamination risk for the ethanol and butanol blended gasoline. Thus, the Kd values for all gasoline compounds for all the SOM fractions tested, including 0%fom, 1%fom, 3%fom and 5%fom, were in the order of UG>B20>E20, indicating greater risk of groundwater contamination for the ethanol-blended gasoline after a spill or leak regardless of the SOM content of the soil. The increase in the water content of soil reduced the sorptive capability of SOM and affected the overall mass distribution of gasoline compounds between the soil solid, soil air and soil water phases estimated with values of Henry’s law constant from the literature. This indicates that the degree of gasoline retention in the vadose zone by SOM could differ during the dry summer and wet winter seasons. This effect was greater for ethanol than butanol. Thus, in all seasons, the amount of gasoline compounds retained by SOM in the vadose zone is likely to be higher for butanol-blended gasoline than ethanol-blended gasoline. Overall, this study indicates that the use of high ethanol volume in gasoline to combat climate change may put the groundwater at greater risk of contamination after spills or leakages from storage. Therefore, to successfully reduce greenhouse gases emissions via high alcohol volume in gasoline and still protect the world’s groundwater resource, this study suggests the use of butanol is more benign than ethanol

Evaluation of non-human factors responsible for accidents in oil and gas companies in Niger Delta

The study was carried out to evaluate the non-human factors responsible for accident causation in the oil and gas companies in the Niger Delta region. These non-human factors (NHFs) were captured using natural occurrence factor (NOF) and site location factors (SLF) while accident causation was conceptualized using rate of accidents (RA) and rate of incidents (RI). Cross-sectional and inferential designs were adopted and population comprised of field-workers of six sampled oil and gas companies in Niger-Delta from which 440 samples were obtained using Multi-stage sampling technique. Data were collected using questionnaire designed based on 5-point Likert and data analysis were done with descriptive statistics and regression using XL-STST version-20.1. The results of the descriptive statistics using weighted average (WA) revealed that the non-human factors which include NOF and SLF are substantial accident causation factors with WA of 3.82 and 3.55>3.00 respectively. and there is high level of accident occurrence which includes RA and RI with WA of 3.92 and 3.99 respectively. The regression analysisthere is positive and significant relationship between non-human factors and accident causation in the oil and gas firms (coefficient of determinant=0.292, p-value=0.000). The study concluded that non-human factors are substantial accident causalities factors in oil and gas firms in Niger-Delta. The study recommended that management of the oil and gas firms in Niger-delta should consider and use safer platforms that could withstand different level of weather adversity in order to assure safety of oil and gas workers in the platform especially deep-sea offshore oil and gas operations because the outcome of the current study has established that non-human factor like natural occurrences and site locations are substantial predictors of accident causation in the oil and gas firms operating in the Niger-Delta

SPATIAL EVALUATION OF WATER QUALITY OF SURFACE AND GROUNDWATER AROUND ARTISANAL REFINING POLLUTED AREA IN EMOHUA LGA, RIVERS STATE

This study evaluated the spatial distribution of water quality for surface and groundwater sampledaround sites of artisanal refining activities in Emohua local government area in Rivers State. Ten ground and tensurface water samples were collected around artisanal refining operation sites within the distances of 0-100m, 100-200m, 200-300m, 300-400m, 400-500m Two control sampleswere obtained at distances of over 10km from the refining sites for both the surface and groundwater samples. The water samples were analyzed for some physicochemical parameters. Water quality index were calculated at difference distances based on measured physicochemical and WHO standards using weighted arithmetic mean technique. The results revealed that the WQI for surface water samples and the control sample were 3.719, 3.700, 2.832, 2.775. 0.098 and 0.115 while that of ground water sample and the control were 1.780, 1.410, 1.778, 0.0518. 0.038 and 0.113 for distance ranges of 0-100m, 100-200m, 200-300m, 300-400m, 400-500m and control sample respectively. These results showed that surface water sources were more polluted than the ground water sources at all the sampled distance range. The results also showed that there was decrease in the WQI with increase in distance away from the artisanal refining site which showed that the water quality improve with increase in distance away of the artisanal refining sites but the surface and ground water samples were mostly unfit for drinking except at distances beyond 400 and 300 respectively as well as the control samples. It was therefore concluded that, based on results of water quality index, that both ground and surface water sources within distances of less than 400 and 300 meter respectively away from the artisanal refining operation are not fit for drinking and must be properly and intentionally treated before drinking

IMPACT OF WORKERS BEHAVIOURAL TRAITS ON SAFETY PERFORMANCE OF PETROL STATIONS IN SELECTED STATES IN THE NIGER DELTA

This study was conducted to investigate the impact of workers behavioural traits on safety performance of petrol stations operating in selected states in the Niger Delta. Two variables were used to capture safety performance, namely near-miss occurrence and accident occurrence while five personality traits factors namely openness, neuroticism, agreeableness, extraversion and conscientiousness were used to capture behavioural traits. The study adopted cross-sectional and correlational research designs. Multi-stage sampling technique was used to sample petrol stations operating in three states in the Niger Delta (Akwa-Ibom, Bayelsa, and Rivers States) while Taro Yamane formula was used to calculate sample size of 440 petrol station attendants from the study population. Structured questionnaire designed based on 5-point Likert scale was used for data collection while reliability of the instruments was determined using Cronbach alpha index. Descriptive statistics and regression model were used for the data analysis. The results of descriptive statistics revealed that the petrol station attendants showed good personality traits (WA= 3.57 > 3.00) and safety performance of the petrol stations was good (WA= 3.47 > 3.00). The regression models revealed that the workers behavioural traits had positive and significant impact on safety performance of the petrol stations (B = 2.192 p-value = 0.001 < 0.05). Therefore, it was concluded that improvement in the workers behavioural traits would trigger corresponding improvement in the safety performance of the petrol stations in the Niger Delta

The Socio-Economic and Environmental Impacts of Petroleum Refinery Operations in the Niger Delta Region

The Niger Delta region, a crucial hub for Nigeria's petroleum resources, encounters significant socio-economic and environmental challenges stemming from both government-owned and artisanal oil refineries. The environmental impacts, particularly air pollution and its subsequent effects on public health and the local economy, remain a primary concern. Through a comprehensive analysis of over 110 sources, this review evaluates the contributions of refinery operations to air pollution and environmental degradation in the Niger Delta. Our findings indicate that emissions from these refineries not only contribute to significant ecological imbalances but also pose severe health risks to local communities. Furthermore, the inefficiencies in refinery operations, characterized by below-standard product output and frequent accidents, have profound economic ramifications, especially for communities reliant on traditional livelihoods. The review identifies critical gaps in environmental regulations and policy enforcement, necessitating an array of solutions, including technological enhancements for better operational efficiency, the development of modular refineries, and thorough policy reforms. The study advocates for a holistic approach to surmount the environmental and health adversities triggered by refinery operations in the Niger Delta. It is imperative to integrate technological advancements, eco-friendly practices, community engagement in governance, and stringent environmental policy implementation. These strategies are vital for diminishing pollution levels and propelling sustainable economic progress within the region.

Effects of Formaldehyde Exposure on Human Body-A Review Article

Formaldehyde, a ubiquitous volatile organic compound, is used extensively in the manufacture of many products and processes across industries, yet little is known of its inherent risks in the occupations. Because of formaldehyde public health significance, many countries and regulatory agencies have issued guidelines, advisories, and regulations for its exposure. These permissible exposure limits are different for different countries and institutions, suggesting that there is currently no global agreement on what comprises safe formaldehyde exposure levels. Formaldehyde has a wide range of chronic toxicity effects affecting different cells, tissues and organs of the body including, but not limited to, neuronal, pulmonary, immunological, haematological, genetic and reproductive and developmental systems. It is also carcinogenic, nephrotoxic and hepatotoxic. Most of the mechanisms through which formaldehyde exerts its toxic effects are not clearly understood. Due to its global economic importance, formaldehyde has clearly come to stay despite its known toxicities. It is proposed that well-designed epidemiologic, in addition to mechanistic and animal studies, need to be carried out to better appreciate the systemic effects of formaldehyde exposure.</jats:p