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No data on the terrestrial toxicity of dipentaerythritol ester of nC5/iC9 acids (CAS 647028-25-9) are available. In accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5 a read across to the structurally similar analogue substance dipentaerythritol hexa esters of pentanoic, heptanoic and trimethylhexanoic acid(CAS 67762-52-1) was conducted to fulfil the data requirements according to Annex VII - IX of dipentaerythritol ester of nC5/iC9 acids (CAS 647028-25-9) in regard to long-term toxicity to soil macroorganisms.

This read-across is justified in detail in the overall summary (IUCLID section 6.1) and within the analogue justification in IUCLID section 13. The source substances consist of the same alcohol component (dipentaerythritol) and similar fatty acid chain lengths as the target substance (C5-9iso for the target substance compared to C5-9 for the source substances, respectively).

The long-term toxicity study with the earthworm Eisenia fetida resulted in no mortality or adverse effects on reproduction up to the highest concentration tested. Therefore, both the NOEC for mortality (28 d) and the NOEC for reproduction (56 d) were determined to be≥1000 mg/kg soil dw.

Based on the result from the structurally related read-across substance dipentaerythritol hexa esters of pentanoic, heptanoic and trimethylhexanoic acid (CAS 67762-52-1) it can be concluded that dipentaerythritol ester of nC5/iC9 acids (CAS 647028-25-9) will not exhibit toxic effects to Eisenia fetida.

This long-term test was conducted in order to take into account the potential persistence of the substance, as well as its low water solubility. Testing of the toxicity to earthworms evaluates the exposure to the test substance via soil pore water, surface contact as well as by ingestion of soil particles. Due to the lack of any mortality or adverse effects in this long-term toxicity test with soil invertebrates, as well as the low bioaccumulation potential, toxicity to terrestrial arthropods cannot be expected. Therefore, additional toxicity tests with these organisms would not be reasonable.

Due to the low water solubility of the substance only low concentrations are expected in the pore water, which is the main exposure route for terrestrial plants. Since the pore water is the main route of uptake for terrestrial plants, the bioavailability of the substance is presumably low. An uptake of the substance by plant roots is also hindered by the high molecular weight of the substance (759 - 1095 g/mol) preventing it from crossing biological membranes. Therefore, tests with soil-dwelling organisms like earthworm, which allow potential uptake via surface contact, soil particle ingestion and porewater (ECHA, 2012), are most relevant for the evaluation of terrestrial toxicity and toxicity to plants. In addition, in the absence of a clear indication of selective toxicity, an invertebrate (earthworm or collembolan) test is preferred, as outlined in ECHA guidance section R.7.11.5.3, page 122.

Dipentaerythritol ester of nC5/iC9 acids (CAS 647028-25-9) shows no inhibition to aquatic microorganisms. The applied test concentration is most likely in the range of concentrations that can be expected in the influent of a sewage treatment plant, as the substance has low water solubility (< 0.0775 mg/L). The ECHA Guidance Document R.7c (ECHA, 2012) states that a test on soil microbial activity will only be additionally necessary for a valid PNEC derivation if inhibition of sewage sludge microbial activity has occurred. Therefore, toxicity to soil microorganisms is considered to be unlikely.

As the test substance is not classified as toxic or harmful, the substance is not considered to cause toxic effects in predators. Additionally, the uptake and bioaccumulation potential is low and thus the test substance is considered to cause no hazard to predators. Thus, a study with birds is not needed due to animal welfare reasons and no PNEC oral is derived from data on mammalian toxicity.