(Z)-N-octadecyldocos-13-enamide

Endpoint summary

Additional information

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. Total duration of study is 56 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 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 is 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 (< 0.05 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 pore water (ECHA, 2017), 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.7.11.5.3, 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.

 

One experimental study is available investigating the potential effects of the test item (CAS No. 10094-45-8) on seedling emergence and growth (ECT, 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. 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.

 

One experimental study is available investigating the potential effects of the test item (CAS 10094-45-8) on nitrogen transformation (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 higher than 1000 mg/kg soil dry weight.