Registration Dossier

Administrative data

Description of key information

NOAEL (28 days repeated dose, Wistar): ≥ 1000 mg/kg bw.

Key value for chemical safety assessment

Additional information

In a repeated dose oral toxicity study in Wistar rats (OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity in Rodents), 2,2',2" -Nitrilotriethanol, propoxylated was administered via gavage to 5 rats/sex/dose at 0, 100, 300, 1000 mg/kg bw for 4 weeks. No death was observed in either sex. No clinical effects were observed in both sexes of all dose groups. There was no effect observed upon haematological, clinical biochemistry or macroscopic examination at any dose. Based on these results the NOAEL was considered to be ≥ 1000 mg/kg bw/day. If at all the slight changes in thyroids of females at 1000 mg/kg were related to the treatment, they are regarded as an indirect and adaptive effect.

The need for further testing for individual NLP polyols under the REACH Regulation can be significantly modified if arrangements for grouping into categories and ‘read across’, based on the principles in Annex XI can be used. The justifications and the proposed categories are set out in Part 1 of Barratt and Illing (2007). 'Read across' based on (a) the same bond linking the core moiety and the repeating unit moiety (b) molecular weight distributions. Experimental data on core substances, repeating units, selected polyols within the category and 'read across' based on bioavailabilities indicates that the propoxylated substances in this category are not classifiable in respect of their repeated dose toxicity. This categorisation for read across has also been used to justify read across for tests required by Annex VII and VIII. There is sufficient available information for an adequate hazard characterisation and a chemical safety assessment. In view of this ‘weight of evidence’ approach and the need to consider animal welfare, no further testing is proposed.

Justification for classification or non-classification

The findings from repeated dose toxicity testing do not warrant classification.