Concentration, Source, and Carcinogenic Risk of PAHs in the Soils from Jiaozhou Bay Wetland

Abstract

16 surface soil samples were collected from Jiaozhou Bay wetland. The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were measured by gas chromatography-mass selective detector (GC/MS). The total concentration of PAHs ranged from 176.1–563.3 ng/g dry weight, with a mean of 345.3 ng/g dry weight. Factor analysis was calculated to apportion sources of PAHs. It was found that the PAHs mainly from coal burning, traffic sources, diesel leakage, coke production, oil exploitation and petroleum leakage. Seven carcinogenic PAHs classified by the IARC were calculated for the health risk assessment. Two groups of people (children and adults) were selected to estimate the carcinogenic risk via ingestion, inhalation, and dermal contact. As a result, the total carcinogenic risks for children and adults were 4.8 × 10⁻⁷ and 8.8 × 10⁻⁷, respectively, and the carcinogenic risks were at acceptable range. Sensitivity analysis was conducted to evaluate the parameters which contributed most to the carcinogenic risk assessment. As as a result, the average lifespan (AT), body weight (BW), BaPeq concentrations (CS), exposure frequency (EF), and exposure duration (ED) contribute most to the carcinogenic risk assessment, and these should be acquired on a site-specific basis.

Key Words:

• carcinogenic risk
• PAHs
• source
• wetland soils