2,2'-iminodiethanol

Toxicity to terrestrial arthropods

Description of key information

Effect values (EC50, EC25) on collembolan adult survival and reproduction were > 1000 mg/kg soil dw.

Key value for chemical safety assessment

Short-term EC50 or LC50 for soil dwelling arthropods:

4 205 mg/kg soil dw

Additional information

In accordance with REACH Regulation (EC) 1907/2006, Annex IX and X, Section 9.4., Colum 2, the toxicity testing to terrestrial organisms shall be proposed depending on the results of the chemical safety assessment. According to Annex I of this regulation, the chemical safety assessment triggers further action when the substance or the preparation meets the criteria for classification as hazardous according to Regulation EC 1272/2008 and its second adaptation 286/2011 or is assessed to be a PBT or vPvB. The hazard assessment of diethanolamine reveals neither a need to classify the substance as dangerous to the environment, nor is it a PBT or vPvB substance, nor are there any further indications that the substance may be hazardous to the environment.
In addition, indirect exposure to soil is unlikely since the substance is readily biodegradable according to OECD criteria. For substances being considered as „readily biodegradable“, it can be assumed that they will be completely biologically degraded within the STP process. Indirect exposure to soil is not likely e.g. via agricultural use of sewage sludge since diethanolamine is readily biodegradable (see IUCLIC Ch. 5.2.1, BASF AG, 1992). Furthermore, for substances not passing the STP-process but being readily biodegradable, it can be assumed that they will be also biological degraded in the surface water within a short time. Direct exposure to soil is not likely, since the substance is not intentionally applied to soil. The substance has no potential to bioaccumulate (BCF = 2.7 L/kg considering all mitigating factors (9.2 L/kg not considering any mitigating factors), according to the BCF baseline model v.04.11, implemented in OASIS Catalogic v5.14.1.5, (BASF SE, 2021). Regarding the charged molecule at pH 7 the log Koc was estimated to be 0.99 (Koc = 10 L/kg) following the method of Franco & Trapp, 2008, 2009, 2010 (BASF, 2021). Therefore, adsorption to solid soil phase is not expected (log Koc < 3).

In conclusion no testing is required. The predicted no effect concentration (PNEC) for soil was derived by applying an assessment factor of 1000 to the lowest EC50 according to REACH Guidance R.10.6.2 as results are available from short-term tests with a producer, a consumer and a decomposer.

 

Assessment

The long-term effects of diethanolamine on the collembola Folsomia candida were studied in a chronic survival and reproduction test according to an Environment Canada method (PTAC, 2006). Adult Folsomia candida survival was adversely affected following exposure to diethanolamine with a chronic LC50 of 8301 mg/kg soil dw. Chronic reproduction did not appear to follow a concentration-dependent pattern until exposed to the second highest diethanolamine concentration (5000 mg/kg soil dw); the concentration-response curve was very steep between 1000 and 5000 mg/kg soil dw. The EC50 and EC25 for number of progeny produced were 4205 mg/kg soil dw and 2101 mg/kg soil dw, respectively. The study does not report NOEC or EC10 values; therefore, the EC50 values will be used for PNEC derivation as acute effect values.

 

The PNEC soil was derived based on experimental data only according to REACH Guidance R.10.6.2 as short-term data are available for producer, consumer, and decomposer.

Therefore, no additional tests on terrestrial arthropods are provided.