Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

The following terrestrial tests have been performed. Below in table the results are summarized.

 Endpoint/species Test guideline   Result  Comment
Reproduction earthworms (Eisenia fetida) OECD TG 222  NOEC28d: 100 mg/kg soil dw (mortality)NOEC28d: 31.6 mg/kg soil dw (body weight)NOEC56d: 31.6 mg/kg soil dw (reproduction) Key study, K1 
 Nitrogen Transformation test OECD 216 

NOEC28d: 100 mg/kg soil dw (nitrate formation rate)

NOEC28d: 100 mg/kg soil dw (nitrate content) 

Key study, K1 
 Terrestrial plan test  OECD 208 EC10: 27.1 mg/kg soil dw  Key study, K1, used for PNEC

ECHA has requested three soil studies for OTNE in their final decision (May 2015, Decision number: CCH-D-2114297145-44-01/F) and were conducted the year after (2016) The results are presented above. The PNEC soil is 2.7 mg/kg soil dw.

It is discussed below that the EP method presents sufficiently conservative results in comparison with the experimental terrestrial toxicity information. The lowest experimental EC10 value is based on the plant tests: 27 mg/kg soil dw. The PNEC soil based on experimental testing results in 2.7 mg/kg soil dw, using an assessment factor of 10.

Additional information

Discussion on the PNEC soil EP method versus aquatic toxicity: The PNEC soil using EP method soil results in 1.11 mg/kg soil dw. The PNEC experimental result in 2.7 mg/kg soil dw. This shows that the PNEC soil is similar using both methods. This shows that the EP method is sufficiently conservative as such and an additional factor of 10 for oral exposure for log Kow > 5 is not needed.

Discussion on PNEC soil versus PNEC sediment:

The second line of evidence results from the long-term sediment toxicity test. The information from the long-term sediment toxicity studies on three types of species result in the lowest NOEC of 14.9 (converted to 2% organic carbon in soil) and the resulting PNECsoil from this set would be 1.49 mg/kg dw.