Details

Autor(en) / Beteiligte

• Claßen, Daniela
• Siedt, Martin
• Nguyen, Kim Thu
• Ackermann, Juliane
• Schaeffer, Andreas

Titel

Formation, classification and identification of non-extractable residues of 14C-labelled ionic compounds in soil

Ist Teil von

• Chemosphere (Oxford), 2019-10, Vol.232, p.164-170

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• The influence of an ionic functional group on the fate of chemicals in the environment, especially the formation of non-extractable residues (NER), has not been systematically investigated. Using 4-n-dodecylphenol[phenylring-14C(U)], 4-n-dodecylbenzenesulfonicacid[phenylring-14C(U)] sodiumsalt (14C-DS-) and 4-n-dodecylbenzyltrimethylammoniumchloride[phenylring-14C(U)] (14C-DA+) all with a high structural similarity, the formation, classification and identification of NER of negatively (14C-DS-), positively (14C-DA+) and uncharged (14C-DP) chemicals were investigated in a sterilized and non-sterilized soil. After 84 days of incubation in non-sterile soil, 40.6%, 21.7% and 33.5% of the applied radioactivity (AR) of 14C-DP, 14C-DS- and 14C-DA+, respectively, were converted to NER. In contrast, in sterile soil NER formation was markedly lower. The NER were further investigated with respect to sequestered, covalently bound and biogenic residues (i.e. NER types I, II, and III). Silylation of 14C-DP, 14C-DS- and 14C-DA+ derived NER released 3.0–23.2% AR, indicating that these were sequestered, whereas the residual NER (12.9–33.1% AR) was covalently bound to the soil. Analysis of extracts derived by silylation showed that 14C-DP, but neither 14C-DS- nor 14C-DA+, were released by silylation, suggesting that DP might be part of the sequestered NER. Acid hydrolysis of the NER containing soil and subsequent analysis of soil extracts for 14C-aminoacids indicated that 2.5–23.8% AR were biogenic residues. Most DP and DS− derived NER were biogenically or covalently bound, whereas DA+ predominantly forms sequestered NER in soil. From these results we propose that chemicals forming high amounts of NER should be investigated regarding types I-III NER because sequestered parent compounds should be considered in persistence assessments. •A chemical charge influences the formation of non-extractable (NER) residues in soil.•Most DP and DS− derived NER were biogenically (type III) or covalently (type II) bound.•DA+ predominantly forms strongly sorbed or physically entrapped (type I) NER in soil.•Not charged DP but neither DS− and DA+ is part of the type I NER.