(1-methyl-1,2-ethanediyl)bis[oxy(methyl-2,1-ethanediyl)] diacrylate

Adsorption / desorption

Description of key information

Adsorption to the solid soil phase is not expected.

Key value for chemical safety assessment

Koc at 20 °C:

1 023

Additional information

QSAR-disclaimer

In Article 13 of Regulation (EC) No 1907/2006, it is laid down that information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI (of the same Regulation) are met.

According to Annex XI of Regulation (EC) No 1907/2006 (Q)SAR results can be used if (1) the scientific validity of the (Q)SAR model has been established, (2) the substance falls within the applicability domain of the (Q)SAR model, (3) the results are adequate for the purpose of classification and labeling and/or risk assessment and (4) adequate and reliable documentation of the applied method is provided. 

 The substance is an UVCB substance. The following four main constituents which concentrations at or above 0.1 % (w/w) were analytically determined:

1.    Constituent 1 (2-{2-[2-(acryloyloxy)-1-methylethoxy]-1-methylethoxy}-1-methylethyl acrylate), ca. 85% (w/w)

2.    Constituent 2 (2-Propenoic acid, 2-[2-(2-hydroxymethylethoxy)methylethoxy]methylethyl ester), ca. 4% (w/w)

3.    Constituent 3 (2-Propenoic acid (1 or 2), (4 or 5), (7 or 8)-trimethyl-10,14-dioxo-3,6,9,13-tetraoxahexadec-15-en-1-yl ester), ca. 3% (w/)

4.    Constituent 4 ((1 or 2)-methyl-2-{(1 or 2)-methyl-2-[(1 or 2)-methyl-2-(2-propenoyloxy)ethoxy]ethoxy}ethyl (5 or 6), (8 or 9), (11 or 12)-trimethyl-14-oxo-4,7,10,13-tetraoxahexadec-15-en-1-oate), ca. 2% (w/w)

According to Regulation (EC) No 1907/2006, Annex VIII, Section 9.3.1, Column 2, the study on adsorption/desorption screening does not need to be conducted if based on the physicochemical properties the substance can be expected to have a low potential for adsorption (e.g. the substance has a low octanol water partition coefficient), or the substance and its relevant degradation products decompose rapidly.

The substance has a log Kow of ca. 2.7 (see IUCLID Ch. 4.7). In addition, the substance is moderately biodegradable (see IUCLID Ch. 5.2.1). Therefore, a study does not need to be conducted.
However, the adsorption constituents Koc were calculated for substances with KOCWIN v2.00, implemented in EPISuite v4.11 (BASF, 2019).

 The following table provides results for the constituents of the substance (impurities or additives are not present in concentrations at or above 0.1 % (w/w)):

	MCI Method Koc [L/kg] / Log Koc	Log Kow Method Koc / Log Koc	Applicability Domain
Constituent 1	26 / 1.41	41.63 / 1.62	Yes
Constituent 2	1 / 0.39	3.32 / 0.52	Yes
Constituent 3	460.1 /2.66	43.25 / 1.63	Yes
Constituent 4	1023 / 3	40 / 1.6	Yes

 

As can be seen from the data compiled above, the predicted log Koc value for all of the constituents of the registration item are rwithin the range between 0.4 and 3 and thus indicates no potential for adsorption

Since TPGDA is uncharged at physiologically relevant pH values, the estimates are representative for the uncharged molecules of the major components.

The remaining “non-specified constituents” sum up to a typical concentration of approximately 6.0 % (w/w). According to GC analytics, more than 45 peaks contribute to this part of the composition of the registration item. Though it is virtually not possible to identify each single peak and assess the respective substance(s) individually, a generic assessment of the environmentally relevant properties of these ingredients may be applied. Multifunctional acrylates are synthesized from alcohols and acrylic acid. As a consequence, the resulting products – including the “non-specified constituents” – are made of the same, similar chemistry. As shown by the evidence provided above, this chemistry basically is subject to ultimate biotic degradation: in none of the four main constituents, a potential metabolite that may be generated from the degradation of these compounds was identified. Therefore, from a scientific perspective, it is extremely likely that also the degradation of the chemically similar “non-specified constituents” of the registration item will not lead to the formation of a persistent metabolite. The raw materials used as well as the conditions of the reaction chosen during manufacture are targeted to produce 2-{2-[2-(acryloyloxy)-1-methylethoxy]-1-methylethoxy}-1-methylethyl acrylate. Side-products beyond the main constituents discussed above are expected to slightly vary in chain lengths and/or branching, but are not anticipated to significantly differ in terms of structural elements – if at all. Therefore, also these structures are deemed degradable by the same metabolic pathways. Consequently, there is no concern that (part of) the UVCB may persist in the environment.

 Hence, based on the available calculated data the adsorption is not expected for main constituents of the TPGDA. The substances are within the applicability domain of the model.

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