(1R)-1-[(4R,4aR,8aS)-2,6-bis(3,4-dimethylphenyl)tetrahydro[1,3]dioxino[5,4-d][1,3]dioxin-4-yl]ethane-1,2-diol

Endpoint summary

Description of key information

In two acute oral toxicity studies, no mortality was noted following a single oral administration of the substance at 5000 mg/kg bw. Body weight gains were not affected by treatment, and no abnormality was noted at necropsy. The only clinical sign of toxicity was soft stools in two females on day of treatment in Glaza (1992) study.
In an acute dermal study conducted according to OECD guideline 402, the estimated dermal LD50 values for male and female rats were determined to be greater than 2000 mg/kg bw following a single cutaneous application at 2000 mg/kg bw. All animals appeared normal and exhibited body weight gain throughout the study. The gross necropsy examinations at termination revealed no macroscopic findings that could be associated with treatment.
An acute inhalation has been waived and does not need be conducted because the test substance has very low vapor pressure (Vp = 1.23 x 10E-6 Pa at 25 °C) and high melting point (261 - 265 °C), so the potential for the generation of inhalable forms is very low. Further, the particle size distribution shows that proportions of inhalable, thoracic and especially respirable fractions are relatively small: proportion of test material having an inhalable particle size less than 100µm is (13.2%); proportion of test material having a thoracic particle size less than 10.2µm (9.72%); proportion of test material having a respirable particle size less than 5.4µm (1.40%). Reliable data on actue toxicity is available for the oral (LD50 > 5000 mg/kg bw) and dermal route (LD50 > 2000 mg/kg bw ), where the substance was clearly not toxic.

Justification for classification or non-classification

Based on the LD₅₀of >5,000 mg/kg bw and >2,000 mg/kg bw for oral and dermal exposure respectively, and the absence of other major significant effects, the test substance does not need to be classified for acute toxicity.