Phenolphthalein

Endpoint summary

Description of key information

The test item does not possess any acute toxic potential below 2000 mg/kg bw (reference 7.2.1 -1).

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
In early studies, the test substance given intravenously in dogs was found to be relatively non-toxic. Moderate toxicity after intraperitoneal injection in rats is reported in SAX’s with an LD50 of 500 mg/kg body weight. Information on oral toxicity of test substance in rodents have been found through several studies undertaken during the National Toxicology Program (NTP), including 14 day, 13 week, and 2 year feeding studies in rats and mice. These studies were published in November 1996 as NTP’s Technical Report Series, No. 465 (TR-465): Toxicology and Carcinogenesis Studies of Phenolphthalein (CAS no. 77 -09 -8) in F344/N Rats and B6C3F1 Mice (Feed Studies).1 In these studies, the dose range applied in oral feed exceeds the limit dose for acute toxicity studies according to the OECD Guideline for the Testing of Chemicals No. 423 throughout the protocols. For example, in the 13 -week study in rats groups of 10 male and 10 or 9 female F344/N rats were given 0, 3000, 6000, 12000, 25000, or 50000 ppm test item equivalent to average daily doses of approximately 200, 400, 800 , 1600, or 3500 mg/kg body weight. All study rats survived the end of the study and no mortality was observed. The final mean body weight of the 50000 ppm females and the mean body weight gains of the females were significantly lower compared to those data of the controls. The final mean body weight and mean body weight gains of all other exposed groups were similar to those of the controls. Thus, in can be concluded that the test substance does not possess any acute toxic potential below 2000 mg/kg bw. These findings suggest that further acute oral toxicity studies for the test substance are scientifically unjustified and should thus not be performed due to animal welfare reasons.
References: Repeated dose toxicity studies: (1) NTP 1996, 14-day oral feed rats (2) NTP 1996, 13-weeks oral feed rats

Reason / purpose for cross-reference:

data waiving: supporting information

Reason / purpose for cross-reference:

data waiving: supporting information

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Additional information

Information on oral toxicity of the test substance in rodents have been observed through several studies undertaken through the National Toxicology Program (NTP), including 14 day, 13 week, and 2 year feeding studies in rats and mice. These studies were published in November 1996 as NTP’s Technical Report Series, No. 465 (TR-465): Toxicology and Carcinogenesis Studies of Phenolphthalein (CAS no. 77 -09 -8) in F344/N Rats and B6C3F1 Mice (Feed Studies)(1). In these studies, the dose range applied in oral feed exceeds the limit dose for acute toxicity studies according to the OECD Guideline for the Testing of Chemicals No. 423 throughout the protocols. For example, in the 13 -week study in rats groups of 10 male and 10 or 9 female F344/N rats were given 0, 3000, 6000, 12000, 25000, or 50000 ppm test item equivalent to average daily doses of approximately 200, 400, 800 , 1600, or 3500 mg/kg body weight. All study rats survived the end of the study and no mortality was observed. The final mean body weight of the 50000 ppm females and the mean body weight gains of the females were significantly lower compared to those data of the controls. The final mean body weight and mean body weight gains of all other exposed groups were similar to those of the controls. Thus, in can be concluded that the test item does not possess any acute toxic potential below 2000 mg/kg bw. These findings suggest that further acute oral toxicity studies for the test substance are scientifically unjustified and should thus not be performed due to animal welfare reasons.  

References: Repeated dose toxicity studies: (1) NTP 1996, 14-day oral feed rats (2) NTP 1996, 13-weeks oral feed rats

Justification for classification or non-classification

Classification, Labelling, and Packaging Regulation (EC) No 1272/2008
The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. Based on available data, the test item is not classified as acute toxicity according to Regulation (EC) No 1272/2008 (CLP), as amended for the fourteenth time in Regulation (EU) 2020/217.