Fatty acids, C16 and C18-unsatd., triesters with trimethylolpropane

Toxicity to soil macroorganisms except arthropods

Description of key information

No effects of the test substance on terrestrial organisms are expected.
NOEC (56 d)  >= 1000 mg/kg for Eisenia fetida (OECD 222)

Additional information

Experimental data on the toxicity offatty acids, C16-18 (even numbered) and C16-18-unsatd. (even numbered), triesters with trimethylolpropane (CAS 68002-79-9)to soil macroorganisms are not available. This assessment is based on read across data from the to the category members 2-ethyl-2-[[(1-oxoheptyl)oxy]methyl]propane-1,3-diyl bisheptanoate (CAS 78-16-0) and 2-ethyl-2-(((1-oxoisooctadecyl)oxy)methyl)-1,3-propanediyl bis (isooctadecanoate) (CAS 68541-50-4). All read across substances are triesters, which contain the same alcohol trimethylolpropane (TMP). 2-ethyl-2-[[(1-oxoheptyl)oxy]methyl]propane-1,3-diyl bisheptanoate (CAS 78-16-0) has the shortest fatty acid chain length of the two source members. This may represent the highest possible mobility in soil, although in general a low mobility is expected for all TMP esters due to the low water solubility, low vapour pressure and high log Koc. The other end of the category is covered with data from 2-ethyl-2-(((1-oxoisooctadecyl)oxy)methyl)-1,3-propanediyl bis (isooctadecanoate) (CAS 68541-50-4), which represents the longer chain lengths within the TMP group of the polyol esters category. This is in accordance with Regulation (EC) No 1907/2006, Annex XI, 1.5. Grouping of substance and read across approach. Further justification is given within the endpoint summary 6.1 and within the analogue justification section 13.

The long-term toxicity of the read-across substance 2-ethyl-2-[[(1-oxoheptyl)oxy]methyl]propane-1,3-diyl bisheptanoate (CAS 78-16-0) was tested according to OECD guideline 222. The test was conducted with artificial soil that was mixed with the test substance. Earthworms of the species Eisenia fetida were exposed to the test substance for 28 days and then removed from the test substrate. The survival rate and growth (body weight) of the specimen were determined. After another 28 days the hatched juveniles were collected from the test substrate and the reproduction rate was recorded. Mortality or a decrease in body weight of the adult earthworms was not observed. Thus a NOEC of 1000 mg/kg soil based on mortality was reported. A NOEC ≥ 1000 mg/kg soil based on the reproduction rate was determined.

The long-term toxicity of the read-across substance2-ethyl-2-(((1-oxoisooctadecyl)oxy)methyl)-1,3-propanediyl bis (isooctadecanoate) (CAS 68541-50-4)was tested according to OECD guideline 222. The test was conducted with artificial soil that was mixed with the test substance. Earthworms of the species Eisenia fetida were exposed to the test substance for 28 days and then removed from the test substrate. The survival rate and growth (body weight) of the specimen were determined. After another 28 days the hatched juveniles were collected from the test substrate and the reproduction rate was recorded. Mortality or a decrease in body weight of the adult earthworms was not observed. Thus a NOEC of 1000 mg/kg soil based on mortality and a NOEC ≥ 1000 mg/kg soil based on the reproduction rate was determined.

Based on the results from structurally related read-across substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5) which are characterized by an equal ecotoxicological profile, it can be concluded thatfatty acids, C16-18 (even numbered) and C16-18-unsatd. (even numbered), triesters with trimethylolpropane (CAS 68002-79-9)does not exhibit effects on soil macroorganisms.