5H-Cyclopenta[h]quinazoline, 6,6a,7,8,9,9a-hexahydro-7,7,8,9,9-pentamethyl-

Endpoint summary

Description of key information

Acute oral toxicity: LD50 is 300 -2000 mg/kg bw in an OECD TG 420 and roughly estimated to be 1850 mg/kg bw.

Acute toxicity inhalation: LC50 is >5.11 mg/L air in an OECD TG 403.

Acute dermal toxicity: LD50 is >2000 mg/kg bw in an OECD TG 402.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

1 850 mg/kg bw

Quality of whole database:

The one acute oral toxicity study available is of sufficient quality for the present dossier.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The one acute inhalation toxicity study available is of sufficient quality for the present dossier.

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The one acute dermal toxicity study available is of sufficient quality for the present dossier.

Additional information

Acute oral toxicity

The substance was tested in an acute oral toxicity test, using the fixed dose method (OECD TG 420) at doses of 2000 and 300 mg/kg bw. At 2000 mg/kg bw, mortality occurred in two out of five animals, while a third animal was killed for humane reasons due to severe clinical signs of toxicity. At 300 mg/kg bw, one animal was killed out of humane reasons due to severe clinical signs of toxicity. Clinical signs at 2000 mg/kg bw included hunched posture, lethargy, pilo-erection, decreased respiratory rate, labored respiration, splayed or tiptoe gait, occasional body tremors, ataxia, dehydration, diarrhea and emaciation. Macroscopy in animals that either died or were humanely killed during the study at 2000 mg/kg bw showed a dark liver or patchy pallor of the liver, dark kidneys, solid substance present in the stomach, epithelial sloughing of the gastric mucosa and hemorrhagic non-glandular epithelium of the stomach. At 300 mg/kg bw, clinical signs included hunched posture, lethargy, pilo-erection. For the animal that was humanely killed during the study, clinical signs included a decreased respiratory rate, labored respiration, splayed gait, prostration and hypothermia. Macroscopy in the animal that was humanely killed during the study at 300 mg/kg bw showed presence of a clear liquid or solid substance in the stomach and a thickened non-glandular epithelium. All surviving animals appeared normal at the end of the study and no abnormalities were noted for these animals during macroscopy. The LD50 result in 300 -2000 mg/kg bw and is roughly estimated to be 1850 mg/kg bw.

Acute inhalation toxicity

The substance was tested in an acute inhalation test (OECD TG 403) at a dose level of 5.11 mg/L. No mortality occurred. Clinical signs observed during the study included decreased respiratory rate, noisy respiration, ataxia, hunched posture, pilo-erection and wet fur. Animals recovered to appear normal from days 3 to 4 post-exposure. Macroscopy showed dark patches on the lungs for three animals. No macroscopic abnormalities were detected amongst the other seven animals. The LC50 result in >5.11 mg/L air.

Acute dermal toxicity

The substance is tested in an acute dermal toxicity test (OECD TG 402) at a limit dose of 2000 mg/kg body weight. No mortality was observed and there were no signs of systemic toxicity. Very slight to well-defined erythema, with or without very slight oedema was noted at the test sites of all animals. Crust formation was also noted at the test site of one female. Test sites appeared normal two to eight days after treatment. Four females showed body weight loss or no gain in body weight during the first week with expected gain in body weight during the second week. The remaining animals showed expected gains in body weight over the study period. No abnormalities were noted at necropsy. The LD50 result in >2000 mg/kg bw.

Justification for classification or non-classification

The substance has to be classified as acute toxicity category 4 and shall be labelled with H302: Harmful if swallowed according to EU CLP (EC no. 1272/2008 and its amendments).

The substance does not have to classified for acute toxicity by the inhalation and dermal route according to EU CLP (EC no. 1272/2008 and its amendments).