Vertical distribution of nonylphenol and nonylphenol ethoxylates in sedimentary core from the Beipaiming Channel, North China

The vertical profiles of nonylphenol(NP)and nonylphenol ethoxylates(NPEOs) were investigated in a sediment core from the Beipaiming Channel,North China using high sensitive LC-MS and GC-MS methods.In this core,relatively high concentrations of NP and NPEOS occurred in the surface sediment(≤40 cm),with the maximum value of NP and NPEOs reaching 3539 and 12735 ng/g,respectively,whereas,no NP or NPEOs were detected in deeper sediments(＞40 cm).The high concentrations of NP and NPEOs in the surface layers suggested recent inputs in this area.NPEOs with short ethoxy chains(NPnEO,n=0-3)were dominant in the NPEO mixture with percentages from 54%tO 78%.which were similar to the distribution of homolog NPEO in efttuents from nearby sewage treatment plants(STPs).indicating that the channel received the effluents from these STPs.The sewage treatment ratio was quite similar to that found in North America before the 1980s.Finally,the concentrations of NP and NPEOS were related to the total organic carbon(TOC)(P＜0.001),suggesting that TOC was an important factor for vertical distribution of NPEOs and NP from the Beipaiming Channel.