N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine

Endpoint summary

Description of key information

The acute oral toxicity of 77PD is moderate, indicated by an oral LD50 value of 730 mg/kg bw in Sprague-Dawley rats (Monsanto Co. 1973); based on this finding 77PD should be classified as harmful if swallowed.
The acute dermal toxicity of 77PD is low, indicated by a dermal LD50 value of > 3160 mg/kg bw in rabbits after single application (Monsanto Co. 1973). 

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

730 mg/kg bw

Acute toxicity: via dermal route

Endpoint conclusion

Dose descriptor:

LD50

Value:

3 160 mg/kg bw

Additional information

Acute toxicity: oral

The acute oral toxicity of 77PD was evaluated in acute oral gavage study with Sprague-Dawley albino rats (Monsanto Co 1973). Undiluted test substance was administered by gavage to male and female rats at doses of 501, 631, 794 and 1000 mg/kg bw. A 10-day observation period followed administration. The oral LD50 was 730 mg/kg bw. Mortality occurred in all treatment groups (1/5, 1/5, 3/5, 5/5 at 501, 631, 794 and 1000 mg/kg bw, respectively. Clinical signs were observed and included reduced appetite and activity (lasting 4 to 6 days in survivors), increasing weakness, collapse and death. Autopsy of decedents showed hemorrhagic areas of the lungs, liver discoloration and acute gastrointestinal inflammation. Viscera of survivors appeared normal.

The moderate toxicity of 77PD is supported by limited documented publications with oral LD50 values in rats of 750 mg/kg bw (Stasemkova 1971) and 1600 mg/kg (McCormick 1972, Takahashi 1975). For mice LD 50 values of 800 mg/kg bw (McCormick 1972, Takahashi 1975) and 1700 mg/kg bw (Stasemkova 1971) were published.

Acute toxicity: dermal

The acute dermal toxicity of the test substance 77PD was evaluated in acute dermal toxicity study with New Zealand albino rabbits (Monsanto Co. 1973). Undiluted test substance was applied for 24 hours directly to the clipped, intact skin of New Zealand albino rabbits (1 animal per dose) at doses of 1260, 2000, 3160, 5010, 7940 mg/kg bw. Mortality occurred at 5010 (1/1) and 7940 mg/kg bw (1/1). The dermal LD50 for the test substance 77PD was greater than 3160 mg/kg bw. Clinical signs were observed and included reduced appetite and activity (lasting 3 to 7 days in survivors), increasing weakness, collapse and death (2 to 3 days after application). Autopsy of decedents showed lung hyperemia, liver discoloration, enlarged gall bladder, and gastrointestinal inflammation. Viscera of survivors appeared normal; except for two animals, which exhibited slight discoloration of liver and kidneys.

Justification for classification or non-classification

Based on the findings of the above mentioned acute oral toxicity study (Monsanto Co 1973, LD50 730 mg/kg bw) the test substance 77PD is classified as harmful if swallowed to the classification criteria 67/548/EWG (R22) and regulation no. 1272/2008 (GHS) (cat. 4).