Assessment of Environmental and Occupational Hazards Associated with Crude Oil Exploitation: A Toxicokinetic and Engineering-Based Framework for Sustainable Mitigation

The study evaluated environmental and occupational risks, associated with crude oil exploitation in Niger delta in Nigeria, using an integrative toxicokinetic-engineering framework. Environmental samplings of air, water, land, and sediment were conducted in Nembe, Gbaramatu, and Bonny, and analysed using GC-MS and AAS for quantitative purposes. While PK-Sim, under the benefit of PBPK modelling, provided an estimation of the kinetics of benzene and benzo[a]pyrene. Benzoic acid-deriving compounds urinary benzoic acid levels in 72.6% of workers exceeded the benzene BEIs (t,t-muconic acid: 615.2 ug/g), blood lead levels of 83.4% were above 10ug/dl (mean=17.3ug/dl), and 69.8% had PAN-DNA adducts more than 4ng/mL. Logistic regression analysis revealed that exposure to gas flaring (OR = 3.42, p < 0.001) and more than 10 years of service (OR = 3.12, p = 0.002) were significant predictors of benzene burden. Good relationships were documented between pollutants and biomarkers (for example, benzene, t-MA: r = 0.681, p < 0.001). PCA explained 90.5% of the variance using three axes of exposure, which comprised VOCs, heavy metals, and PAHs. Risk Quotients were at high risk levels: benzene (RQ = 3.00), lead (RQ = 3.75), and arsenic (RQ = 3.00). The engineering audit identified critical failures: a pipeline break (RPN = 250), gas detector problems (RPN = 216), and non-implementation of SCADA. The study advances the science of exposures by confirming biomonitoring-toxicokinetic relations and proposing the application of predictive maintenance, biomarker monitoring, the policy of Personal Protective Equipment, and specific pollutant remediation as a way to decrease total toxic exposure.