Hexane, 1,6-diisocyanato, homopolymer, N-butyl-1-butanamine-blocked

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Additional information

A combined 28-day repeated dose toxicity study with the reproduction/developmental toxicity screening test of Hexane, 1,6-diisocyanato, homopolymer, N-butyl-1-butanamine-blocked was conducted in rats by oral gavage according to OECD 422 guideline and GLP (WIL Research Europe, 2013).

Rationale for dose levels

Based on the results of the 14-Day dose range finding study, the dose levels for this combined 28-day oral gavage study with reproduction/developmental toxicity screening test were 100, 300 and 1000 mg/kg bw/day.

 

Study outline

After acclimatization, four groups of ten male and ten female Wistar Han rats were exposed by oral gavage to the test substance at 0, 100, 300 and 1000 mg/kg bw/day. Males were exposed for 29 days, i.e. 2 weeks prior to mating, during mating, and up to termination. Females were exposed for 42-56 days, i.e. during 2 weeks prior to mating, during mating, duringpost-coitum, and during at least 4 days of lactation.

 

Evaluated parameters

The following observations and examinations were evaluated: mortality / viability, clinical signs (daily), functional observations and locomotor activity (males: Week 4; females: end of lactation),  body weight and food consumption (at least at weekly intervals), clinical pathology (males: Week 4; females: end of lactation), macroscopy at termination, organ weights and histopathology on a selection of tissues, and reproduction/developmental parameters, consisting of mating, fertility and conception indices, precoital time, number of corpora lutea and implantation sites, gestation index and duration, parturition, maternal care, sex ratio and early postnatal pup development (mortality, clinical signs, body weights and macroscopy).Formulations were analyzed once during the study to assess accuracy, homogeneity and stability.

Results/discussion

Accuracy, homogeneity and stability of formulations were demonstrated by analyses.

Parental results:

No parental toxicity was observed up to the highest dose level tested (1000mg/kg bw/day).

 

Reproductive results:

No reproduction toxicity was observed up to the highest dose level tested (1000mg/kg bw/day).

 

Developmental results:

No developmental toxicity was observed up to the highest dose level tested (1000mg/kg bw/day).

 

Conclusion

 

Treatment with Hexane, 1,6-diisocyanato, homopolymer, N-butyl-1-butanamine-blocked by oral gavage in male and female Wistar Han rats at dose levels of 100, 300 and 1000 mg/kg body weight/day revealed no parental, developmental or reproductive toxicity up to 1000 mg/kg body weight/day.

 

Based on these results, a parental, reproduction and developmental No Observed Adverse Effect Level (NOAEL) of at least 1000 mg/kg bw/day was determined.

Short description of key information:
OECD 422 (WIL Research Europe), NOEAL = 1000 mg/kg (parental, reproduction and development)

Effects on developmental toxicity

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Justification for classification or non-classification

Based on the available data, the test substance is not classified with regard to toxicity to reproduction according to Directive 67/548/EEC (DSD) and Regulation (EC) No 1272/2008 (CLP), respectively.