Distribution and Fate of Petroleum Hydrocarbons in Coastal Seawater, Sediment, and Bivalves after the Hebei Spirit Oil Spill Incident

Abstract

An estimated 12,547 kilo liters (10,900 M/T) of crude oil was spilled in December 2007 after the collision between the oil tanker Hebei Spirit and a barge carrying a crane. More than 375 km of western coastline of Korea were impacted by the spill, threatening the health of natural marine ecosystem and various mariculture activities. Spatiotemporal variations of oil contamination were investigated until 2018 since the spill. Polycyclic aromatic hydrocarbons (PAHs) and/or total petroleum hydrocarbons (TPH) in seawater, sediment, and bivalves were analyzed. Immediately after the spill, the direct impact of the Hebei Spirit oil spill was clearly recognized at most sites surveyed. TPH concentration in seawater was 154 times higher than the Korean marine water quality standard of 10 ppb on average. PAH concentrations in sediments measured immediately after the spill ranged from 3.2 ng/g to 71,200 ng/g, with an average of 3,800 ng/g. Parent and alkylated PAHs in bivalves increased up to 1,200 and 106,000 ng/g, respectively, which were 60 and 1000 times higher than the pre-spill concentration level. The oil component concentrations in seawater and bivalves were several orders of magnitudehigher than those detected at reference sites. The distribution of oil contamination showed considerable variability depending on the proximity to the spill location. Thereafter the oil contamination in the media have decreased gradually to