Benzene, Toluene, Ethylbenzene, Xylene, and Styrene (5VOCs) Distributions at the Barrier Island System in the Nakdong River Estuary, South Korea

Abstract

Total Volatile Organic Compounds (TVOCs) were extracted from 18 surface sediment samples collected in and around barrier island system in the Nakdong River Estuary (NRE) on the southeastern Korean Peninsula in May 2015. TVOC emissions from sediments were measured using a Thermal Desorption System-Gas Chromatograph-Mass Selective Detector (TDS-GC-MSD) for 30 min at 25 degrees C at the National Center for Inter-university Research Facilities (NCIRF), Seoul National University, South Korea. The thermal extractor (Gerstel, Germany) was equipped with an adjustable oven (temperature, 25-350 degrees C) to heat a glass tube containing the sample. TVOC concentrations ranged from 2.6 to 64.9 ng/g-dry weight (average, 13.2 +/- 13.8 ng/g-dry weight), with benzene in the range 0.6 to 0.8 ng/g-dry weight (average, 0.7 +/- 0.1 ng/g-dry weight), toluene in the range 0.4 to 1.3 ng/g-dry weight (average, 0.9 +/- 0.3 ng/g-dry weight), and xylene in the range 0.0 to 0.8 ng/g-dry weight (average, 0.2 +/- 0.2 ng/g-dry weight). No evidence of ethylbenzene or styrene was found at the sampling sites. TVOC concentrations were highest at Sinjado zone, at 64.9 ng/g-dry weight. This area corresponds to back-barrier fringe marsh sediments sorted by location and terrain. Although TVOC levels in many sediments were below the detection limit, this method can be used to estimate their behavior in marine environments. This monitoring in the NRE can draw the necessity of safety management and Sediment Guidance Values (SGVs) establishment as to contributing to remediation of contaminated sediments.