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Environmental fate & pathways

Endpoint summary

Administrative data

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Distribution estimates by QSAR show, in accordance with the vapour pressure, high log Koc and very low water solubility, that the substance mainly distributes to sediment (affinity for organic matter), followed by water (where it is mainly non-dissolved) and only to a minor extent in air or soil.

In the atmosphere, no direct photolysis is expected, but AOP v1.92, in EPIsuite, predicts a half-life ranging 5 -11 hours in the atmosphere due to reaction with oxygen radicals (indirect photolysis). Furthermore the vapour pressure is limited, limiting volatilisation.

In water, no significant abiotic degradation is expected due to poor solubility. The substance was not easily biodegradable, and was inherently biodegradable but not fulfilling ECHA Guidance R7b criteria (less than 20% degraded). This is consistent with Level III Fugacity Models predicting a water half-life of 37.5 days. Further testing is not relevant as water is not the critical compartment in terms of exposure (minimal solubility) and degradation (quicker degradation estimated than in other compartments).

In sediment, Level III Fugacity Models predict a water half-life of 337.5 days.

In a recent publication on another tetrapropylene-based BAB, soil samples analyzed at 11-year interval evidenced less than 9%, and no decline, for the complete substance and for TAB3 (most persistent component), resp. As this substance was abandoned as a soap/detergent in the 1960’s due to its persistence, it may be considered that these data are indicative of an important persistence (vP). For BAB components the Level III Fugacity Models consider a soil half-life of 75 days, which seems much less persistent (non P). However the estimates are probably less reliable than the experimental data.

Using BioHCwin QSAR, which gives an overall non-compartment specific prediction, the estimated half-lives range 19-117 days, with a similar range of 35-64 days for the C12 fraction (main fraction).

Additional information