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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

The Koc of test substance was estimated using KOCWIN v 2.01 program (EPISuite v 4.11), to be 3251 L/kg (log Koc= 3.51) with MCI method and 11250 L/kg (log Koc= 4.05) Log Kow method.

Additional information

The soil adsorption and desorption potential (Koc) of the test substance was estimated using Molecular Connectivity Index (MCI) and Log Kow of the KOCWIN v 2.01 program (EPI Suite v 4.11). The Koc values were estimated using SMILES codes as the input parameter. Using the MCI and log Kow methods, the predicted Koc values were estimated to be 3251 L/kg and 11250 L/kg respectively. The corresponding log Koc values were 3.51 and 4.05 (US EPA, 2022). The test substance is a Quaternary Ammonium Compound (QAC). Adsorption of QACs seem to occur mainly by an ion-exchange mechanism and depends on cation-exchange capacity of the sorbent and variety of other parameters (Boethling, 1994). The training set for the Koc estimation of this program did not include any QACs. Therefore, the Koc estimate is outside the program's prediction domain. Therefore Koc predictions were not considered to be accurate. Based on the above information, the test substance is expected to have a strong adsorption potential (US EPA, 2012) to soil and sediment, leading to negligible to slow migration to ground water. Overall, the Koc predictions for the test substance using KOCWIN model of EPI Suite TM can be considered to be less reliable with low to moderate confidence.