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Terrestrial data of (Z)-N-Octadecyldocos-13-enamide (CAS No. 10094-45-8) are available for three trophic levels. All studies were performed according to international guidelines and GLP.

One experimental study is available investigating the toxicological effects of the test item (CAS 10094-45-8) to earthworms (ECT, 2017). The study was performed according to OECD guideline 222. Adult Eisenia fetida (4 x 10 animals per concentration, the fresh weight was between 300 and 600 mg) were exposed for 28 days in an artificial soil to the nominal concentrations of 16.3, 29.4, 52.9, 95.3, 171.5, 308.6, 555.6 and 1000 mg/kg dry soil. After 28 d adult worms were removed from the soil and the juvenile worms reared for a further four weeks. The artificial soil comprised 10% peat, 20% kaolin clay and 70% industrial quartz sand. The parental LC50 was determined to be greater than 1000 mg/kg dry soil, the highest rate tested. A treatment related NOEC of 1000 mg/kg dry soil was achieved. The EC50 for the number of juveniles on Day 56 was determined to be >1000 mg/kg dry soil and a NOEC of 1000 mg/kg dry soil was achieved.

Experimental data on the toxicity of (Z)-N-Octadecyldocos-13-enamide (CAS No. 10094-45-8) to terrestrial arthropods are not available. The substance is characterised by a high log Koc (log Koc > 5) indicating a considerable potential for adsorption to the soil particles but as the substance is highly insoluble in water (< 0.01 mg/L), only low concentrations are expected in the pore water. Therefore, tests with soil-dwelling organisms like earthworm which allows potential uptake via surface contact, soil particle ingestion and porewater (ECHA, 2012), are most relevant for the evaluation of soil toxicity. 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., page 122. Thus, it can be assumed that earthworms would be highly exposed to toxicants in soil and hence are most sensitive to the potential adverse effects of the substance. In accordance with Regulation (EC) No 1907/2006, Annex XI, Section 1.5 a read across to the structurally similar analogue substance (Z)-N-octadec-9-enylhexadecan-1-amide (oleyl palmitamide, CAS 16260-09-6) will be conducted to fulfill the data requirements according to Annex IX of (Z)-N-Octadecyldocos-13-enamide (CAS No. 10094-45-8) in regard to long-term toxicity to soil macroorganisms. This read across is justified in detail in the analogue justification in IUCLID Section 13. The study is not yet available since a testing proposal according to OECD 222 was submitted for the read-across substance (Z)-N-octadec-9-enylhexadecan-1-amide (oleyl palmitamide, CAS 16260-09-6). However, no additional test with soil macroorganisms will be proposed for (Z)-N-Octadecyldocos-13-enamide (CAS No. 10094-45-8). The PNECsoil will be calculated using long term toxicity data to earthworms giving a robust PNECsoil for the chemical safety assessment. . For the revision of the chemical safety assessment, the PNEC as well as PEC values will be evaluated critically, as soon as the result of the Earthworm Reproduction test is available. We will demonstrate that the PEC/PNECsoil is < 1, i.e. no indication of risk from the confirmatory long-term soil toxicity testing to earthworms. Thus, no further toxicity testing for soil organisms needs to be done.

One experimental study is available investigating the potential effects of the test item (CAS No. 10094-45-8) on seedling emergence and growth (Croda, 2017) of plants. The study was performed according to OECD guideline 208 under GLP conditions. For this study six species of non-target terrestrial plants (2 monocots and 4 dicots) were planted in a natural sandy loam soil (standard soil LUFA Sp 2.3) immediately after test item application. Five test item concentrations were tested with each species: 10, 31.6, 100, 316 and 1000 mg test item /kg soil dry weight and left to grow under controlled conditions for 19 days (B. napus), 20 days (P. sativum) or 21 days (remaining species) following 50% emergence of the control plants. On day 7 and 14 or 15 (Brassica napus) after 50% emergence of control, seedlings were evaluated visually. At test end, seedlings were counted, evaluated visually, and harvest to determine shoot fresh weight. The effects of the test item on the emergence and growth of seedlings were tested in the laboratory. At concentrations up to and including 1000 mg/kg soil dry weight the test item had no statistically significant adverse effect on either seedling emergence, seedling survival or shoot fresh weight of any of the six test species. The NOEC and LOEC were therefore determined to be ≥1000 mg/kg soil dry weight and > 1000 mg/kg soil dry weight, respectively. Due to the lack of adverse effects effective concentrations could not be calculated and are assumed to be higher than 1000 mg/kg dry weight.

One experimental study is available investigating the potential effects of the test item (CAS 10094-45-8) on nitrogen (ECT, 2017) of terrestrial microorganisms. The study was performed according to OECD guideline 216 under GLP conditions. Test item was ground with fine quartz sand using a pestle and mortar prior to being mixed together with the sand into the test soil (Lufa standard soil type 2.3). The soil test was amended with ground lucerne grass green meal (5.0 g/kg soil). Test item was tested at five concentrations ranging from 260 mg/kg soil dry weight (T1) to 1000 mg/kg soil dry weight (T5) against an untreated control (C) with four replicates, each. Nitrate of the soil was measured after test item application on day 0, and 28 days after test item application. Due to the lack of a dose-response relationship, effective concentrations could not be calculated. Consequently, the EC50, EC25, and EC10 can be considered to be higher than 1000 mg/kg soil dry weight.