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Amines, C12-14-tert-alkyl, mixed sec-Bu and iso-Bu phosphates (CAS 96690-34-5) is an UVCB substance comprising negatively charged organophosphate and positively charged amine groups. The substance is characterized by a water solubility of 1322 mg/L at 25 °C and pH 3.57 and a low vapour pressure of ≤ 54 Pa at 20 °C. The Log Kow values are summarized within the table below (see Table 1) and were within a range of 0.686 and 5.6347. The Log Koc was calculated based on representative components of 2-methylpropyl dihydrogen phosphate, bis(2-methylpropyl) hydrogen phosphate and 2-methyltridecan-2-amine with a Log Koc of 1.55, 1.78 and 4.75, respectively. Hydrolysis is not considered to be a relevant degradation pathway of the substance. The amine components of the test substance are generally hydrolytically stable in the environment where as the organophosphate groups hydrolyse slowly in contact with water.

Furthermore the amine groups have a high potential for adsorption to soil and sediment. Whereas the adsorption potential of the organophosphate components is low. Thus a higher mobility of the organophosphate components in soils can be expected. Biodegradation is expected to be low. Based on the outcome of the biodegradation screening tests according to OECD 301 F and B the substance is not readily biodegradable (0% after 56 d). Therefore it can be considered that the substance is potentially not mineralized under environmental conditions.

Table 1: Log Kow values of the components of Amines, C12-14-tert-alkyl, mixed sec-Bu and iso-Bu phosphates

Log Kow

Component

0.686

2-methylpropyl dihydrogen phosphate

0.686

butan-2-yl dihydrogen phosphate

2.1419

bis(2-methylpropyl) hydrogen phosphate

2.1419

dibutan-2-yl hydrogen phosphate

2.1419

butan-2-yl 2-methylpropyl hydrogen phosphate

4.6525

2-methylundecan-2-amine

5.1436

2-methyldodecan-2-amine

5.6347

2-methyltridecan-2-amine