Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

1,1,3,3 -tetramethylbutyl peroxyneodecanoate is inherently biodegradable (25% degradation) and poorly water soluble (33µg/L). The log Kow of 1,1,3,3 -tetramethylbutyl peroxyneodecanoate exceeds 6.5.

The Log Koc of 1,1,3,3 -tetramethylbutyl peroxyneodecanoate is also high with a value of 4.7. These physical chemical parameters suggest that 1,1,3,3 -tetramethylbutyl peroxyneodecanoate will bind strongly to organic matter and soil/sediment and therefore has the potential to accumulate in these compartments. When considering the rapid hydrolysis of 1,1,3,3 -tetramethylbutyl peroxyneodecanoate however which has a half life as a worst case of <24 hours. The parent peroxide will not be able to persist for long periods in an aquatic environment or in compartments where water is present. In addition the self accelerating decomposition temperature of 1,1,3,3 -tetramethylbutyl peroxyneodecanoate is 15 ºC, above which the parent molecule cannot persist. When further considering the highly reactive nature of the peroxide group and known reactions with metal ions and organic material as well as the measured poor stability in ecotoxicity testing, the relevance of basing an environmental risk assessment purely on the parent material should be carefully considered. Properties of the known degradation products should also therefore be considered for a more complete assessment.

The primary degradation product is 2,4,4 -trimethyl pentan-2 - ol which has been confirmed analytically in additional studies. Neodecanoate is also likely to be formed based on structural analysis of the parent molecule. Distribution modeling of both degradation components in Epiwin (Level III Fugacity Model) suggest a tendency to accumulate in the soil (approximately 60%) and in water (approximately 30%) with small distribution to the other remaining compartments. The predicted half-lifes in water and soil are 360 and 720 hours respectively. Volatilization from water bodies is expected for Neodecanoate (6 -71 days)and

2,4,4 -trimethyl pentan-2 - ol (1 -14 days). Both are predicted to be rapidly degraded by hydroxyl radicals in the atmosphere.

Consideration should be made to the mentioned fate and distribution information if further testing is required as a result of the chemical safety assessment.

Additional information