1,1,3,3-tetramethylbutyl peroxyneodecanoate

Endpoint summary

Description of key information

Oral 28-day (OEC407) and 90-day (OECD 408) repeated dose toxicity studies are available.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

100 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

K1: The study was performed according to OECD guidelines and GLP.

System:

male reproductive system

Organ:

other: sperm

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

The oral administration of 1,1,3,3-Tetramethylbutyl peroxyneodecanoate (CAS Number: 51240-95-0) to rats for twenty-eight days at dose levels up to 1000 mg/kg bw/day resulted in treatment-related findings in both sexes at 30, 300 and 1000 mg/kg bw/day. The findings noted in females of the high dose group were considered minimal and therefore 1000 mg/kg bw/day may be considered a NOAEL for females. Similar findings were noted in males at the high dose but, in addition, microscopic kidney findings were noted in all treatment groups which were characterised by hyaline droplets, increased tubular degeneration/regeneration and granular casts and at 1000 mg/kg bw/day by interstitial inflammatory infiltrates. These findings were consistent with alpha-2u-globulin nephropathy, consistent with well documented findings peculiar to the male rat in response to treatment with some hydrocarbons, and with no human relevance. Excluding these kidney findings the NOAEL for males was considered to be 300 mg/kg bw/day based on findings on haemoglobin, erythrocyte count and haematocrit at 1000 mg/kg bw/day, the aetiology of which was uncertain.

In the 90-day study, the oral gavage administration of 1,1,3,3-tetramethylbutyl peroxyneodecanoate (CAS# 51240-95-0) to male and female Wistar Han™:RccHan™:WIST strain rats at 10, 100 or 300 mg/kg bw/day resulted in toxicologically significantly lower sperm concentration and motility with an associated higher number of sperm abnormalities at the high dose. Such findings were still noted in males previously treated with 300 mg/kg bw/day after a 28-day treatment-free period. Although group mean sperm concentration and motility were lower at 100 mg/kg bw/day compared to controls, in the absence of associated sperm morphological and histopathological findings this observation was considered of low toxicological significance if at all. A dose level of 100 mg/kg bw/day was established as NOAEL for systemic toxicity in the male rat. In contrast, there were no findings of toxicological significance in the females up to a dose level of 300 mg/kg bw/day which could therefore be established as a NOAEL in the female rat. 

Justification for classification or non-classification

The oral (gavage) administration of 1,1,3,3-tetramethylbutyl peroxyneodecanoate (CAS# 51240-95-0) to male and female Wistar Han™:RccHan™:WIST strain rats at a dose level of 300 mg/kg bw/day for 90 days resulted in toxicologically significantly lower sperm concentration and motility with an associated increase in sperm abnormalities. Such findings were still noted in males previously treated with 300 mg/kg bw/day after a 28-day treatment-free period. The dose level of 100 mg/kg bw/day was therefore established as NOAEL for systemic toxicity in the male rat. As there were no changes of toxicological significance in females up to a dose level of 300 mg/kg bw/day, the dose level of 300 mg/kg bw/day was established as NOAEL in the female rat. 

Based on the results from the 90-day oral toxicity study in rats the substance is classified as a Category 1B Reproductive Toxicant (H360F; see also 7.8.1).