Fingerprinting Analysis and Characterization of Hydrocarbons in Sediment Cores from the Pearl River Estuary, China

Abstract

The Pearl River Delta (PRD) in southern China has undergone rapid urbanization and industrialization over the past few decades, leading to a substantial accumulation of hazardous organic compounds and a significant environmental impact. Forensic analysis of estuarine sediments is critical in order to uncover the contamination history and evaluate the level of contamination of the aquatic system and its ambient regions. A number of hydrocarbons and hydrocarbon groups including polycyclic aromatic hydrocarbons (PAHs), biomarkers, and diamondoids were found in representative sediment cores collected in the Pearl River Estuary (PRE) with average values determined to be 1,300, 288, and 5.85 ng/g dry weight in core #1 (inner shelf) and 283, 26.8, and 2.06 ng/g dry weight in core #2 (outer shelf), respectively. The results clearly suggest that the contamination in PRE sediment was derived from various inputs including petrogenic, biogenic, and pyrogenic sources. Because diamondoids are naturally absent from modern sediments that are free from petroleum contamination, in addition to the signatures of determined alkylated PAHs and biomarker terpanes and steranes, the presence of trace diamondoid compounds provides further evidence of petroleum contamination in the offshore and coastal areas of the PRE.

Keywords:

• forensic analysis
• oil fingerprinting
• biomarker
• diamondoid
• polycyclic aromatic hydrocarbons
• sediment
• Pearl River Estuary