Propylidynetrimethanol, ethoxylated

Endpoint summary

Additional information

Phototransformation in air

Estimated half-lives for the components of this UVCB substance range from 3.4 to 13.8 hours (West, 2010).

 

Hydrolysis

Propylidynetrimethanol, ethoxylated is found to be stable at 50°C at all three pH-values (4, 7 and 9). Therefore, it can be assumed that the test item is also stable at 25°C and no half-life times and hydrolysis rates were calculated. Polyether V 531 as an NLP contains different molecular weight fractions ( = NLP-fractions) which behave similar in hydrolysis reaction (Currenta, 2009).

 

Biodegradation

Bayer Industry Services (2007) gives that within the test period of 28 days, a degradation of 30.3 % was determined for Propylidynetrimethanol, ethoxylated according to the “Manometric Respirometry Test“ (1992) corresponding to OECD 301 F. Therefore, this substance has to be classified as "Not Readily Biodegradable". This result is supported by AnoxKaldnes (2008) reporting of a degradation of 38 % in 28 days with an OECD 301 assay. However, AnoxKaldnes (2008) prolonged the test and report of 52 % degradation after 42 days with the plateau of degradation still not being reached. This may advise that Propylidynetrimethanol, ethoxylated is not persistent in the environment.

Further, Currenta (2009) gives that, performing an OECD 302 C assay on inherent biodegradability, the degradation of Propylidynetrimethanol, ethoxylated was 34 % within 27 days. Therefore, this substance has to be classified as "Not Readily Biodegradable".

 

Biodegradation in water and sediment

Data waiving: In accordance with REACH Annex XI, degradation simulation testing in water and/or sediment does not need to be conducted as from the chemical safety assessment it can be concluded that there is no risk for the aquatic compartment. A further refinement of the PECs using additional information on the degradation of the substance and its degradation products in water and sediment is therefore not required.

 

Biodegradation in soil

Data waiving: In accordance with column 2 of REACH Annex IX, degradation simulation testing in soil does not need to be conducted. The substance is used exclusively in manufacture of polymers/elastomers, where it is completely reacted into these products; and as a result will have no direct or indirect exposures to the soil environment. 

 

Bioaccumulation: aquatic / sediment

Data waiving: In accordance with column 2 of REACH Annex IX, the bioaccumulation test on fish does not need to be conducted as the substance has a low potential for bioaccumulation (log Kow≤3). 

 

Adsorption / desorption

The homologous components of this UVCB substance possess ionizable hydroxy groups, whose estimated pKa values range from 14.2 to 15.5 for the lowest- and 14.1 to 14.7 for the highest-molecular weight homologues. These are considere to be irrelevant for the chemical safety assessment (West, 2010).