Quantifying the exposure of humans and the environment to oil pollution in the Niger Delta using advanced geostatistical techniques

Abstract

The Niger Delta is one of the largest oil producing regions of the world. Large numbers and volumes of oil spills have been reported in this region. What has not been quantified is the putative exposure of humans and/or the environment to this hydrocarbon pollution. In this novel study, advanced geostatistical techniques were applied to an extensive database of oil spill incidents from 2007 to 2015. The aims were to (i) identify and analyse spill hotspots along the oil pipeline network and (ii) estimate the exposure of the hydrocarbon pollution to the human population and the environment within the Niger Delta. Over the study period almost 90millionlitres of oil were released. Approximately 29% of the human population living in proximity to the pipeline network has been potentially exposed to oil contamination, of which 565,000 people live within high or very high spill intensity sectors. Over 1000km of land has been contaminated by oil pollution, with broadleaved forest, mangroves and agricultural land the most heavily impacted land cover types. Proximity to the coast, roads and cities are the strongest spatial factors contributing to spill occurrence, which largely determine the accessibility of sites for pipeline sabotage and oil theft. Overall, the findings demonstrate the high levels of environmental and human exposure to hydrocarbon pollutants in the Niger Delta. These results provide evidence with which to spatially target interventions to reduce future spill incidents and mitigate the impacts of previous spills on human communities and ecosystem health.

Petroleum Hydrocarbons Contamination of Surface Water and Groundwater in the Niger Delta Region of Nigeria

“…The results obtained in this study indicated that the environment has been polluted and the total petroleum hydrocarbon concentrations in water sample at the wellhead stations were above 10 mg l -1 which is the maximum permissible limit recommended by the Federal Ministry of Environment in Nigeria [110]. In a related study, Obida et al [42] used spatio-temporal analysis techniques to identify petroleum hydrocarbon pollution hotspots along the pipeline network, and to quantify the exposure of residents and the environment to petroleum hydrocarbons pollution in the Niger Delta region. The results obtained in this study demonstrate the high levels of environmental and human exposure to petroleum hydrocarbon pollutants in the Niger Delta [42].…”

“…This accounts for more than 70 % of the overall hydrocarbon reserves of sub-Saharan Africa [34,37]. Although the Niger Delta region is one of the most petroleum hydrocarbons resource-rich regions in the world, it remains mired in cycles of conflicts that have perpetuated underdevelopment, threaten human security [21,39], habitat destruction [40], bunkering/artisanal refining and petroleum contamination of the natural environment [1,5,17,31,41,42]. Overall, a brief history of petroleum exploration and production in the Niger Delta region has been extensively reviewed by few researchers [1,5,43].…”

“…Over the years, oil and gas industries operating in the Niger Delta region have created huge pollution problems with over 4,000 oil spills since 1991 [50,51]. Analysis of the oil spill data from 2007 to 2015 reveals that a total of over 90 million litres of crude oil had been spilled into the Niger Delta region [42]. According to Ordinioha and Brisibe [23], an average of 240,000 barrels of crude oil are spilled in the Nigeria's Niger delta region every year and the spillage may be attributed to unknown causes (31.85 %), third party activity (20.74 %), and accidental and/or equipment failure (17.04 %).…”

“…According to Ordinioha and Brisibe [23], an average of 240,000 barrels of crude oil are spilled in the Nigeria's Niger delta region every year and the spillage may be attributed to unknown causes (31.85 %), third party activity (20.74 %), and accidental and/or equipment failure (17.04 %). Although many of the largest oil spills in the world have been caused by accidental terrestrial blow outs, leakages from pipelines due to sabotage, operational failures and neglected maintenance may account for most of petroleum contamination of terrestrial environment in the Niger delta region [5,42,52,53]. The unsustainable activities of petroleum industries in the oil-rich region like the Niger Delta region reflect the inadequate effective statutory laws and regulations as well as lack of regulatory enforcements for environmental protection [1,11,19,40,54,55,56].…”

“…Although inadvertent discharges of petroleum hydrocarbons constitute environmental problems and human health risks, the local residents in Ogoni community attempted to deal with petroleum hydrocarbons contamination in order to use the contaminated land for agriculture and residential purposes [5]. Considering the fact that about 22 % of petroleum hydrocarbon-contaminated land area is arable land with a significant exposure route to humans [42], petroleum hydrocarbons contamination can have both short and long term adverse effects on the environment and human health.…”