2-ethylhexyl diphenyl phosphate

Endpoint summary

Description of key information

Acute oral toxicity:
Standard acute method (no guideline followed): LD50 > 15800 mg/kg (male/female rat).
Acute inhalation toxicity:
Standard acute method, Limit test (similar to OECD 403): LC50, 6h = 2.1 mg/l (nominal) (vapor, male rat).

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

15 800 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Dose descriptor:

LC50

Value:

2 100 mg/m³ air

Additional information

In the key acute oral toxicity study of 2EHDPP, a range finding study, the undiluted compound was fed by stomach tube at 6 doses (1 female rat at 2000, 5010, 7940, and 5 rats/sex at10000, 12600, and 15800 mg/kg). Toxic symptoms included diarrhea for 1 day, reduced activity and appetite, and tremors and increasing weakness to near collapse lasting 5 to 7 days in animals of the last 3 dose groups. One female died at dose 12600 and at 15800 mg/kg. Survival time was 3 to 5 days. At autopsy there were haemorrhagic areas of the liver, lungs, and kidneys, and intestinal inflammation. The oral LD50 was thus found to be > 15800 mg/kg.

In the supporting study the acute oral toxic effects of Santicizer 141 was tested in male and female rats in combination with Triacetin up to 20% Sancticizer 141. The most critical median lethal dose (LD50) of Santicizer 141 was found at the tested combination of Triacetin + 10% Santicizer 141, being 14500 mg/kg bw.

In the key acute inhalation toxicity study, 5 male rats were exposed to Sancticizer 141 at a concentration of 2.1 mg/l as vaporized test material for 6 hours.. All animals survived the 6 hour exposure period; 3 of 5 test animals succumbed during 10 day observation period. The LC50 was calculated to be 2.1 mg/l (nominal concentration, 6 h exposure).

In the available supporting study, conducted according to a method resembling OECD 403, a 4-hour inhalation exposure of 10 rats to aerosol mixture of Santicizer 141 at a mean analytical concentration of 4.8 mg/l did not produce mortality. Signs exhibited included increases in secretory responses, respiratory distress, reduced activity and matted coat. A transient decrease in body weight was noted. As no deaths occurred the tested concentration can be considered as LC0.

In an additional supporting study the acute toxicity of Santicizer 141 was investigated by intraperitoneal (i.p.) injection in male and female mice, at the following doses: 631, 794, 1000, and 1260 mg/kg. Survival time was 1 to 5 days with most deaths occurring within 3 days. The i.p. LD50 for male and female mice was 930 mg/kg with lower and upper limits of 850 to 1020 mg/kg.

Justification for classification or non-classification

Based on the available information and according to the EU criteria outlined in Annex I of 1272/2008/EC and Annex VI of 67/548/EEC, 2EHDPP does not need to be classified for acute oral toxicity. Classification for toxicity by inhalation is not conclusive.