Registration Dossier

Administrative data

Description of key information

A key acute oral study on female rats was available J-37, in which the LD50 was determined to be: > 300 < 2000 mg/kg bw. The LD50 cut-off value according to OECD 423 test guideline was 500 mg/kg bw. 

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Dose descriptor:
LD50
500 mg/kg bw

Additional information

A reliable acute oral study was performed with J-37 according to OECD Guideline 423 (NOTOX, 2010). Initially, J-37 was administered by oral gavage to three female Wistar rats at 2000 mg/kg body weight. In a stepwise procedure additional group of females were dosed at 2000 and 300 mg/kg body weight. All animals were subjected to daily observations and weekly determination of body weight. Macroscopic examination was performed on the day of death or after terminal sacrifice (Day 15).

All females at 2000 mg/kg were found dead or sacrificed in moribund condition on Day 2. No mortality occurred at 300 mg/kg. At the 2000 mg/kg dose level the following clinical signs were observed: Lethargy, flat/hunched posture, piloerection, watery discharge from the eyes, pale appearance and/or hypothermia on Day 1 and/or 2 (all animals). At 300 mg/kg dose the levels hunched posture and/or piloerection on Day 1 (all animals) were found.

Macroscopic post mortem examination of the animals that were found dead or sacrificed for ethical reasons during the study at the 2000 mg/kg dose level revealed, watery-clear fluid in the abdominal cavity in one animal, a beginning stage of autolysis in two animals and hard contents of the stomach in all anaimls. At the 300 mg/kg dose level, pelvic dilation of the kidneys (one animal) was seen.

Therefore the oral LD50 value of J-37 in Wistar rats was established to be within the range of 300-2000 mg/kg body weight. According to the OECD 423 test guideline, the LD50 cut-off value was considered to be 500 mg/kg body weight.

Justification for classification or non-classification

According to DSD and CLP classification criteria for acute oral toxicity, J-37 should be classified as: harmful if swallowed (Category 4).