Nitriles, C16-18

Endpoint summary

Description of key information

Acute toxicity: Oral LD50 > 5,000 mg/kg for rat (LD50 limit test - no mortality)  

Additional information

In a standard LD50 limit study with Tallownitrile, no mortality was observed following the oral application of 5 g/kg of tallow nitrile to 5 male and 5 female rats. Only limited toxicity was observed consisting of oily appearance of body surfaces, and one male animal with respiratory rales on Day 6. All animals appeared normal from Day 7 through Day 14. One female showed a decrease of BW in the course of the second week. All other body weights were normal. At necropsy 14 days after dosing one female showed few yellow areas on the intestines, and an abnormality of the left ovary was noted in another animal.

Justification for classification or non-classification

Only limited to no toxicity was observed after oral dosing of 5000 mg/kg. Also comparable other nitriles as Coconitrile and Oleylnitrile showed no mortality up to highest tested dose of 5000 mg/kg body weight. HT-nitrile can be expected to have similar low acute oral toxicity as well, and hence no classification for acute oral toxicity is indicated.

 

Based on the very low water solubility and relative high Pow of 5, the rate of transfer to the epidermis is probably limited. However, the molecular size is not large and high Pow favours uptake in the stratum corneum. As worst case, 100% dermal absorption is assumed although in view of anticipated slow uptake into epidermis, systemic peak concentrations will be lower following acute dermal exposures compared to the oral route.

Tallownitrile is further mildly irritating to skin, and not irritating to the eyes, and consequently it is not expected to exert serious systemic toxicity by dermal or inhalation routes even when uptake is to be considered similar as following oral route.

Physical-chemical properties of HT-nitrile, being a paste at room temperature with a relatively low vapour pressure (Probably much less than the vapour pressure of 1.8 Pa at 20°C for Coconitrile) and water solubility (for C16 part in Coco < 0.005 mg/L), would also limit the likelihood of significant exposures by inhalation.

Consequently, HT-nitrile need not be classified for acute toxicity by dermal or respiratory route.

Alkylnitriles do not contain aliphatic, alicyclic and aromatic hydrocarbons. Also lack of surface activity (based on structure) indicates there is no aspiration hazard for HT-nitrile.