Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

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Additional information

Experimental data on the toxicity the substance to terrestrial organisms are available for earthworms (soil macroorganisms) and soil microorganisms. Both groups of soil organisms play an important role in the nutrient cycle of terrestrial ecosystems. Earthworms are responsible for the breakdown and incorporation of organic matter into the soil. Soil microorganisms influence the transformation of nutrients and nutrient cycling processes in soil. Thus different exposure pathways are covered by the selected test species. Earthworms will be mainly exposed via the uptake of soil material and dermal exposure whereas soil microorganisms are mainly exposed via soil pore water. The substance is characterized by a high water solubility (WS >1000 g/L) and a log Koc of 3.2 - 3.7. Furthermore the substance is not readily biodegradable. Thus, in accordance Chapter R.7c of the ECHA Guidance on information requirements and chemical safety assessment (ECHA, 2017) long-term tests were conducted in order to assess the toxicity of the substance to terrestrial organisms. The toxicity to earthworms was tested according to OECD guideline 222 with Eisenia fetida as test species. During an exposure period of 56 days (in total) the mortality of adult earthworms after 28 d as well as the reproduction rate were recorded. The substance affected the reproduction rate of the annelids. The determined NOEC(56 d) was 62.5 mg/kg soil dw.

The effects of the substance on the metabolic activity of the nitrogen-N formation rate (nitrate) of soil microorganisms were determined according to OECD Guideline 216 over a 28 day period. There was no evidence that exposure to the test substance inhibited the nitrogen transformation activity of soil microflora at the range of concentrations applied. The no-observed effect concentration (NOEC) was 100 mg test substance/kg soil dry weight.