An accelerated solvent extraction and gas chromatography-flame ionization detector method to rapidly determining and assessing total petroleum hydrocarbon contamination in soil from Fushan oilfield, China

A high-efficient method for determining the total petroleum hydrocarbon (TPH) was established by gas chromatography-flame ionization detection, coupled with an efficient 10 m short chromatographic column; the analyzing period was narrowed to 5 mins. The limits of detection of the method included 1.47, 4.02, and 0.69 mg/kg, and the corresponding limits of quantification reached 4.45, 12.2, and 2.10 mg/kg for the three fractions C-10-C-16, C-17-C-34, and C-35-C-40, respectively. The method was employed to real samples to achieve the routine environmental monitoring of TPH in polluted sites from Fushan oilfield, China. As revealed from the analysis of 30 soil samples in the study area, a wide range of TPH concentrations were achieved: 61.6-7300 mg/kg (average, 1055 mg/kg) for Sigma C-10-C-16, 438-14,280 mg/kg (average, 4544 mg/kg) for Sigma C-17-C-34, 25.4-638 mg/kg (average, 250 mg/kg) for Sigma C-35-C-40, and 617-15,348 (average, 5848 mg/kg) for Sigma C-10-C-40, respectively. According to the Nemerow integrated pollution index, the Fushan oilfield has been slightly polluted by TPH. As suggested from the distribution of TPH concentrations, the main sources of TPH in soil samples of Fushan oilfield included oil spills during temporary storage, transportation, and oil exploitation. Adopting the developed method to delve into oilfield soil samples further verifies the effectiveness of the method, indicating that the method can well meet the growing demand of regulatory guidelines for related risk assessment and environmental monitoring and remediation strategy formulation.