1,2-diacetoxybut-3-ene

Endpoint summary

Description of key information

Only standard information required at REACH Annex VIII is available for assessing the toxicokinetics for the test substance. The available test data do not permit extensive conclusions concerning absorption, metabolism or excretion to be conclusively drawn. Acute toxicity (via the oral route) was relatively low, and repeated oral administration resulted in minor effects on the pancreas in animals dosed at 750 mg/kg/day. No toxicity was observed by the dermal route.

Key value for chemical safety assessment

Bioaccumulation potential:

low bioaccumulation potential

Additional information

Repeated oral administration in a 28 day repeated dose study to rats provided a NOAEL of 225 mg/kg/day. At 750 mg/kg/day there was a slight increase in ALAT and ALP enzymes which could have been related to adverse changes (mild exocrine cell necrosis) in the pancreas in animals at this dose. The histopathological changes at this dose indicate that some adsorption and distribution of the test substance can be expected.

 

In the reproductive screening assay (OECD 421) a NOAEL to rats of 120 mg/kg/day was provided for effects on parental animals (including reproductive indices) and offspring. This was predominantly based on a decreased fertility index and number of implantations observed at 480 mg/kg/day (and a trend towards decreased fertility index at 240 mg/kg/day). A decrease in bodyweight gain was also observed on postnatal day 13 at 240 and 480 mg/kg/day in males and 480 mg/kg/day in females. As the only effect on offspring was on bodyweight gain, it is likely to be as a result of maternal toxicity rather than the potential for inherent toxicity to developing offspring.

 

At 120 mg/kg/day no adverse effects were noted and it is possible that bioelimination through normal metabolic and excretory pathways allows some removal of the test substance, with the potential for these pathways to be overwhelmed at the higher doses. Based on the relatively low Log Kow values (1.53), bioaccumulation of the test substance is not expected.

 

Acute toxicity of the test substance by the oral route was relatively low although still considered to be harmful when considering the relevant CLP classification. Acute toxicity via the dermal route was low with no effects observed up to the standard limit dose.

 

Some positive results observed in genotoxicity assays were not shown to appear when conducting appropriate in vivo tests, and accordingly the substance is considered not to be genotoxic.