[No public or meaningful name is available]

Hydrolysis

Administrative data

Endpoint:

hydrolysis

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
According to REACH Annex XI, “2. TESTING IS TECHNICALLY NOT POSSIBLE”, 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. Annex VIII lists also limited water solubility as such a restricting property.
The substance Amines, C12-14-tert-alkyl, reaction products with O,O-di-C1-14-alkyl hydrogen phosphorodithioate is an UVCB substance, consisting of an amine part, i.e. C12-14-tert-alky-amines, mainly the C12 variety, and O,O-di-C1-14-alkyl hydrogen phosphorodithioate, so the substance consist of two individual UVCBs which may not all be quantitatively determinable. So it is impossible to track down all possible degradation products, if any.
In an OECD 105 study, the shake flask method was used to determined the water solubility of the test item to 13 mg/l for the Amine, C12-14-tert-alkyl cation content, and 10.5 mg/l for the O,O-di-ethylhexyl hydrogen phosphorodithioate anion content at pH6.6 to 6.7 and a test temperature of 20.0 ± 0.5 °C. For the amine part, hydrolysis can be excluded due to the lack of functional groups (e.g. esters, carbamates, epoxides, halomethanes, selected alkyl halides and phosphorus esters) that are hydrolytically reactive under environmental conditions. Alkanes and amines, as contained in the Amine, C12-14-tert-alkyl cations, are, on the other handside, hydrolytically stable functional groups, indicative for a half-life > 1a at 25°C. Therefore, this fate process will not contribute to a measurable degradative loss of the substance from the environment.
Thiophosphoric acid esters however may undergo hydrolysis. According to OECD TG 111, one concentration of the test substance should be used; it should not exceed 0.01 M or half of the saturation concentration, which corresponds to 6.5 mg/ml here. The analytical method should be sufficiently sensitive to quantify test substance concentrations down to 10 % or less of the initial concentration. In this case, a quantitative determination of 0.65 µg/l would be needed, which is technically highly according the current state of art, as due to other components contained in the O,O-di-C1-14-alkyl hydrogen phosphorodithioate aside the main constituent O,O-di-ethylhexyl hydrogen phosphorodithioate, may not allow a specific determination.
So, when getting in contact with water, the test item dissolves immediately into C12-14-tert-alky-amines and O,O-di-C1-14-alkyl hydrogen phosphorodithioate, of which the former is considered stable, and so, as a worst case assumption for further risk assessment, the whole substance should be considered hydrolytically stable. In addition, due to the low water solubility and UVCB nature, a suitable method as required by OECD TG 111, would not be able to be established, so further testing is not required according to REACH Annex XI, section 1.2.