840 / 2024-09-19 16:07:41

Pollution characteristics and ecological risks of typical organic pollutants in sediments from fishing ports in Circum-Bohai-Sea region

Polybrominated diphenyl ethers; Polycyclic aromatic hydrocarbons; Phthalate esters; Sediments

 



 


 




(School of Resources and Environment, Qingdao Engineering Research Center for Rural Environment, Qingdao Agricultural University, Qingdao 266109, China)



The fishing harbor in the Bohai Sea is susceptible to organic pollutants such as polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), and phthalate esters (PAEs) due to its special geographic location. It was found that the sediments of fishing harbors in the Bohai Sea were widely contaminated by these three pollutants, with the highest detection rate of 16 PAEs ranging from 92.5% to 100%, while the detection rates of 14 PBDEs and 16 PAHs also ranged from 63.8% to 100% and 74.3% to 100%, respectively.PAEs were 4.23-20.59 μg/kg, 1092.87-4196.88 μg/kg and 8.53-86.13 mg/kg, respectively. Globally, the content of PBDEs belonged to the medium level of contamination, while the content of PAHs and PAEs belonged to the medium-high level of contamination.

Geographically, PBDEs were mainly concentrated in the southern part of Liaodong Peninsula, Liaodong Bay and Bohai Bay, PAHs in the southern part of Liaodong Peninsula, Liaodong Bay, Bohai Bay and Yellow River Delta, and PAEs in the southern part of Liaodong Peninsula, the Yellow River Delta area and the eastern part of Shandong Peninsula.

In terms of composition, decabromodiphernyl ether（BDE-209) and 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) are important congeners of PBDEs, with BDE-209 accounting for 70.2% on average; di(2-ethylhexyl) phthalate (DEHP) and diethyl phthalate (DEP) are important congeners of PAEs, and the six prioritized controlled PAEs accounted for 70.6% of the total; low molecular weight PAHs such as acenaphthene (Ace), fluorene (Flu), phenanthrene (Phe), and naphthalene (Nap) were the important congeners of sediment PAHs, with an average percentage of 67.3%.

The use of products containing PBDEs and PAEs, wastewater discharges and atmospheric deposition were the main sources of these pollutants, while oil pollution and tailpipe emissions were the main sources of PAHs. The ecological risk assessment indicated that PBDEs and PAHs have low to medium potential ecological risks, while PAEs have medium to high potential ecological risks. The main ecological risks for PBDEs are from tetrabromodiphenyl ether, pentabromodiphenyl ether, and decabromodiphenyl ether, and the risks for PAHs are mainly from the low molecular weight PAHs such as the 2-ring and 3-ring PAHs, and the risks for PAEs are mainly from dimethyl phthalate.

Keywords: Polybrominated diphenyl ethers; Polycyclic aromatic hydrocarbons; Phthalate esters; Sediments