Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Nonanoic acid, esters with adipic acid and trimethylolpropane is characterised by a low water solubility (WS of grade one: 22 μg/L to 43 μg/L (pH 6.3), WS of grade two: 13.5 μg/L (pH 6.3)) and high log Koc values calculated for the single substance constituents (log Koc >5). The available study on biodegradation demonstrated ready biodegradability of Nonanoic acid, esters with adipic acid and trimethylolpropane (70% in 28 d, OECD 301B). The ready biodegradability indicates that the substance is not persistent in the environment. The substance will be extensively eliminated in conventional sewage treatment plants due its ready biodegradability. Furthermore in the case insoluble chemicals enter a standard Sewage Treatment Plant (STP), they will be largely removed in the primary settling tank and fat trap and thus, only limited amounts will get in contact with activated sludge organisms (Guidance on information requirements and chemical safety assessment, Chapter R.7b; ECHA, 2017). The substance is generally not expected to be present in the water column due to the low water solubility. Furthermore the high log Koc values of the substance constituents (Log Koc >5, QSAR) indicates a potential for adsorption to sewage sludge. The substance constituents do not completely fall within the applicability domain of the model and thus the results are not completely reliable. However, the calculated high log Koc values indicate a high adsorption potential. Thus, further reduction of the substance concentration in the water column due to adsorption is possible (Guidance on information requirements and chemical safety assessment, Chapter R.7b; ECHA, 2017). The substance quantities released to water bodies via STP effluents are therefore negligible.

Due to the low volatilization potential of the substance (VP <0.0001 Pa at 20 °C, QSAR, ARChem SPARC. version 4.6) an accumulation in air and subsequent transportation and deposition into other environmental compartments is not expected.