Polycyclic aromatic hydrocarbons in the surface sediments of China's Eastern Beibu gulf: Unveiling distribution...

This study focuses on the eastern Beibu Gulf in Guangxi, China, aiming to deeply analyze the pollution status of polycyclic aromatic hydrocarbons (PAHs) in the surface sediments of this sea area. During the research, surface sediment samples were collected from 12 stations, and the contents of 16 PAHs in them were determined. Diagnostic ratio methods, principal component analysis (PCA), sediment quality benchmark method, toxicity equivalent factor (TEF) method, and risk quotient (RQ) method were comprehensively applied to conduct a comprehensive study on their distribution characteristics, sources, and risks. The results show that the pollution degree of PAHs in this sea area is at a low-to-medium level. The total concentration range is 82.05-98.63 ng·g^-1, with an average value of 91.46 ng·g^-1. In terms of composition, it is mainly dominated by three - and four - ring PAHs, resulting in a relatively low overall toxicity risk. Through source analysis, it is found that PAHs mainly come from biomass and coal combustion, and there is also a small contribution from petroleum and its combustion processes. Through comprehensive analysis by multiple risk assessment methods, the ecological risk of PAHs in this sea area is at a low level. The results of this study provide crucial data support and scientific basis for environmental management, pollution prevention and control, and ecological protection in the eastern Beibu Gulf, and are of great significance for promoting the sustainable development of this area.