Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Environmental stability:

The keystudy showed that DOTE at pH 9, 7 and 4 can be considered hydrolytically stable. After 5 days at 50 °C less than 10% DOTE was hydrolyzed (t 0.5 25°C > 1 year).

The substance is n ot readily biodegradable, however will degrade in the environment. The key study for biodegradability (Beimborn, 2000), reported 30-40% degradation of the registered substance after 28 days and 40 -50% after 74 days. The substance is therefore considered as very persistent as defined by Annex XIII of EC Regulation 1907/2008.

Bioaccumulation:

The bioaccumulation data is available. In the Bouwman, 2010 study Dioctyltin was found to have (as a worst case) a BCF value of 100. The worst case BCF value does not meet the criteria for classification as a bioaccumulative or very bioaccumulative substance as set out by Annex XII of EC Regulation 1907/2008.

Adsorption/desorption:

According to Annex XI section 2 of the Regulation EC 1907/2006; testing for a specific endpoint may be omitted, if it is technically not possible to conduct the study as a consequence of the properties of the substance. This is also in accordance with the adaptations stated in Annex VIII, column 2 section 9.3.1.

In the study by Baltussen (2010), the following statement was included concerning determining an adsorption coefficient of the test material:

“ The test substance can only be analysed after derivatisation, but using derivatisation, a distinction between intact test substance and breakdown products can no longer be made. The test substance cannot be chromatographed through a liquid chromatography column in its intact form.

In conclusion, the adsorption coefficient of the test substance could not be performed according to the OECD 121 method. Since it is not possible to specifically analyse the intact test substance with any technique at low levels which is required due to the expected low water solubility of the test substance, the OECD 106 study is not considered to be an alternative.”