Triphenyl phosphate

Endpoint summary

Description of key information

Triphenylphosphate (TPP) is not irritating to skin. The irritation potential of TPP on the mucous membrane of the eye is very low. 

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

The skin irritation potential of TPP was determined in a study according to international standards (OECD 404). Three rabbits were treated for 4 hours by occlusively applying 500 mg of moistened test substance to the clipped dorsal skin (2 x 3 cm) and observed daily for 14 days. Erythema and oedema formation were evaluated. No signs of irritation was detected. The irritation index was 0.0.

These findings were also confirmed by other studies listed in the table below:

Study type	Species	Endpoint	Exposure	Result	Reference
Skin irritation	Rabbit	Erythema, Eschar and Oedema formation	500 mg TPP; semi-occlusive; 4 hours	Irritation index 0.0, not irritating	Bayer, 1990
Skin irritation	Rabbit	Erythema, Eschar and Oedema formation	500 mg TPP; occlusive; 24 hours	Irritation index 0.0, not irritating	Ciba-Geigy, 1983
Skin irritation	Rabbit	Erythema, Eschar and Oedema formation	500 mg TPP; semi-occlusive; 24 hours	Irritation index 0.0, not irritating	FMC Corp, 1976

The occular irritation potential of triphenyl phosphate of the rabbit eye was determined in a test according to OECD 405. The treated eyes were rinsed 24 hours after instillilation. No sign of irritation was observed.

Similar findings were recorded in a study conducted according to US regulations (16 CFR 1500.42) employing 4 hours treatment without rinse in 6 rabbits (Group 1) and rinsing after 4 seconds in 3 additional rabbits (Group 2). In Group 1 conjunctival effects were observed in all 6 animals. These effects cleared during the 72 -hour observation period. In Group 2, no occular effects were observed in any of the three animals. The test substance was found to be mildly and transiently irritating when test substance was not washed out.

Triphenyl phosphate was minimally irritating when tested in 6 New Zealand white rabbits in a study according to US regulations. 100 mg of the test substance was instilled into the conjunctival sac of the left eye. The eyelids were then held shut for 1 second. After 30 seconds the test substance was flushed out of the eyes of the three rabbits. Very slight reactions were seen in 2/3 washed and 3/3 unwashed eyes 1 hour after application of the test substance. The reactions were less severe at 24 hours although all washed and unwashed eyes were affected. 3/3 washed eyes and 1/3 unwashed eyes were normal at 48 hours, 1 unwashed eye at 27 hours and the remaining unwashed eye at day 6/. Slight opacity and damage to the surface epithelium was seen in 1 unwashed eye at 24 hours. This was no longer present at 48 hours. Triphenyl phosphate in New Zealand white rabbits was minimally irritating.

These findings were also confirmed by another study rated 4. The data available on occular irritation is is sufficient (rated 1 and 2) and is listed in table below:

Study type	Species	Endpoint	Exposure	Result	Reference
Occular irritation	Rabbit	Effects on iris, cornea and conjunctivae	Neat product, 24 hours	Not irritating	Bayer, 1990
Occular irritation	Rabbit	Effects on iris, cornea and conjunctivae	Neat product, 100 mg/eye, rinsed after 30 seconds or not rinsed	Minimally irritating	Ciba-Geigy, 1983
Occular irritation	Rabbit	Effects on iris, cornea and conjunctivae	Neat product, 100 mg/eye, rinsed after 4 seconds or not rinsed	Minimally irritating	FMC Corp, 1976

Justification for classification or non-classification

Triphenyl phosphate does not possess dermal irritation potential based on the available data. The occular irritation potential of triphenyl phosphate is very low. Therefore based on the available dermal and occular irritation studies in animals and on EU Regulation 1272/2008 no classification for skin or eye classification is warranted.