Registration Dossier

Ecotoxicological information

Toxicity to terrestrial plants

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Key value for chemical safety assessment

Additional information

The toxicity of 1-Hexanamine, 2-ethyl-N,N-bis(2-ethylhexyl)- (CAS 1860-26-0) to terrestrial plants was investigated in two consecutive studies according to OECD 208, considering the effect parameters shoot length and dry weight for the determination of effect values.

 

The former OECD 208 guideline study (BASF SE 2014; report no.: 65E0387/05G014) was performed according to GLP with 6 different species (Avena sativa, Brassica Napus, Triticum aestivum, Glycine max, Lycopersicon esculentum & Fagopyrum esculentum). However, due to calculation problems with the data structure in ToxRat, some endpoints could only be estimated in this study by an expert judgment. Therefore, the critical endpoints have been re-evaluated for the species Avena sativa, Brassica Napus & Triticum aestivum in the subsequent OECD 208 guideline study (BASF SE, 2014; report no.: 65E0387/05G017). For evaluation, both studies will be assessed in a weight-of-evidence approach. The gathered data from both studies are considered equivalent to data from a long-term study as the former study was conducted with 6 different species. Therefore the assessment of toxicity is based on the NOEC values determined in both studies on the basis of shoot length and dry weight.

 

In the first study (BASF SE 2014; report no.: 65E0387/05G014) the 21-d NOEC values based on dry weight ranged for the 6 species from < 62.5 mg/kg dw to > 1000 mg/kg dw, The same range applies to the 21-d NOEC values based on shoot length. Comparing all species tested in this study, Avena sativa, Brassica napus and Triticum aestivum turned out to be more sensitive, with dry-weight based NOEC values ranging from < 62.5 to 125 mg/kg dw and a shoot-length based NOEC of < 62.5 mg/kg dw determined for each of the respective species (the value for Brassica napus was determined by expert judgment). In the subsequent study (BASF SE, 2014; report no.: 65E0387/05G017), a shoot-length based 19-d NOEC of ≥ 62.5 mg/kg dw was determined for each of these three species. A 19-d NOEC based on dry weight was only determined for Triticum aestivum; it was found to be 7.8 mg/kg dw.

 

In summary, Triticum aestivum proved to be the most sensitive species with a shoot-length based 19-d NOEC of 7.8 mg/kg dw indicating a potential for long-term effects of 1-Hexanamine, 2-ethyl-N,N-bis(2-ethylhexyl)- (CAS 1860-26-0) to terrestrial plants. However, the test substance is not supposed to be directly applied to soil. In addition, indirect exposure to soil is unlikely to occur in significant dimensions since the substance will reach sewage treatment plants (STPs) in only very small amounts due to the extremely low water solubility. If any, relevant amounts of the substance will reach industrial STPs rather than domestic STPs. Sludge of industrial STPs will usually not be applied on agricultural soil but will be incinerated. Additionally, following the results obtained from the analogous compound Di-(2-ethylhexyl)amine (CAS 106-20-7) the target item 1-Hexanamine, 2-ethyl-N,N-bis(2-ethylhexyl)- (CAS 1860-26-0) is expected to be moderately biodegradable (not readily biodegradable) in soil. Moreover, the risk characterisation ratio (RCR) does not indicate the need for further investigation of risks for the soil compartment (RCR < 1).