Alkylphenols In Surface Sediments Of Guangzhou Section Of The Pearl River And Its Adjacent Branches

Alkylphenols (APs) were measured in 28 surface sediment samples from rivers of Guangzhou section of the Pearl River and its adjacent branches based on the application of the soxhlet extraction method and gas chromatography-mass Spectrometry (selected ion monitoring mode). All the samples were measurable with NP concentration in the range of 31～21885 ng·g^-1 dry weight (mean 3686 ng·g^-1) and OP concentration varied from 0.01～463.01 ng·g^-1 dry weight (mean 40.29 ng·g^-1). In the whole, the Guangzhou Channel showed the highest levels of all the sampling sites and the pollution concentration of APs in this study was generally higher than other industrialized and urbanized areas in the world. Concentrations of NP in our samples were below the 10 days LC50 for Chironomus riparius , however, the two maximum NP concentrations observed is in the same order of magnitude as the lowest effect concentration for subacute toxicity of NP to shrimp, also concerning the estrogenic behavior of AP, LOEC for an eight weeks exposure of Potamopyrgus antipodarum to OP was exceeded in most samples, so more attention should be paid to the ecological risks caused by APs of this region.The sediments' total organic carbon (TOC) contents were correlated with their total nitrogen (TN) contents; the C/N ratios and H/C ratios indicated that the sediments had an mixed organic matter sourse of marine and terrigenous inputs. The correlation analysis showed the concentrations of APs in the sediments were markedly linearly correlated with TOC contents,indicating that sediment organic matter is an important factor controlling the levels of APs in sediments.Also the APs contents and the H/C ratios showed an negative exponential correlation, reflecting the influence of the maturation of organic matters.The APs were also extracted by two sequential accelerated solvents extraction (ASE) from 10 sediments with a mixture of toluene and methanol (1:6), the APs contents measured with the two sequential ASE is over about 1.79 times that measured with the Soxhlet extraction, and were correlated with the TOC contents. The results can be well explained by the dual-mode conceptualization of organic matter, indicating the possible effect of organic matter on the extraction and distribution of native APs in the investigated sediments.