| "We investigated nonylphenolic compounds (NPCs) in 17 composts (fertilizer and/or soil improvement material) made from sewage sludge in 17 prefectures in Japan. The NPCs, nonylphenols (NPs) and nonylphenol n ethoxylates (NPnEOs, n=1-15), were extracted by pressurized fluid extraction method (PFE) and analyzed by HPLC. The concentration (microg/g dry solid) of NPs, total NPnEOs (n=1-15) and total NPCs ranged form 6.5 to 110, from 8.3 to 82.3 and from 23.6 to 174.9, respectively (Table 1). NPnEOs of n>5 (have ethoxylate chains longer than n=5) were not detected in more than 50% of the composts and NPnEOs of n>9 were not detected in more than 75% of the composts. These results suggested that sewage sludge composts contained NPnEOs of which ethoxylate chains were shortened. NP1EO,NP2EO and NP4EO were the major contributor to the NPnEOs concentration, whereas NP8EO were also contained highly in some compost. High concentration of NPs was detected in composts made from anaerobically digested sewage sludge, suggesting that NPs were produced in the anaerobic digestion process and remained in the composting process." |
