Registration Dossier

Administrative data

Description of key information

The substance is already subject of a harmonized classification as skin corr 1B and acute tox 3 (H301. H311, H331). Therefore no robust summary was produced, however the following (non-Klimisch rated) data were found in the literature:

- The oral LD50 was 122 mg/kg in rats.[3] Mice treated by oral gavage died at 100 mg/kg/day and above in an in vivo bone marrow micronucleus assay.[4](see section 7.6.2)

- The 4-hour inhalation LC50 was 252, 172 and 392 ppm = 0.63, 0.43 and 0.97 mg/L, in rats, mice and hamsters, respectively.[1,2,3]

- The dermal LD50 ranged 1329 to 1680 mg/kg in rabbits and guinea pigs.[1,3] One out of four dogs administered a single dermal dose of 300 mg/kg died 6 hours after exposure; all 3 dogs exposed to a single dermal dose of 1,800 mg/kg died within 6 hours.[1]

References of the reviews/sources:

[1] ATSDR. Toxicological profile for hydrazines. 1997

[2] NIOSH. Criteria for a Recommended Standard: Occupational Exposure to Hydrazines. Publication No. 78-172. 1998

[3] PAN Pesticides Database

[4] National Toxicology Program. study N° 020652

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Dose descriptor:
LD50
122 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Dose descriptor:
LC50
630 mg/m³

Acute toxicity: via dermal route

Endpoint conclusion
Dose descriptor:
LD50
1 329 mg/kg bw

Additional information

The substance is already subject of a harmonized classification as T (toxic), R23/25.

Overall, the literature data that could be localized support this classification.

The only exemption is the dermal toxicity data suggest limited dermal toxicity not supporting R24, in spite of the corrosive nature. However the original data source could not be retrieved so the reliability is unsure. Due to the overall very hazardous profile of the substance, warranting maximal protection measures, generation of new animal toxicology data is unnecessary and would be unethical, therefore classification R24 is recommended.

Justification for classification or non-classification

The substance is already subject of a harmonized classification as T (toxic), R23/25. This classification is agreed upon by registrants. For the self classification R24 (H311) was added.