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Administrative data

Description of key information

Subchronic toxicity (90 days):
Oral (feed): LOAEL: 52 mg/kg bw/day for rat (similar to OECD TG 408)

Key value for chemical safety assessment

Mode of Action Analysis / Human Relevance Framework

Additional information

A subchronic study is available in which male and female rats were fed diets containing TCPP for 13 weeks at concentrations corresponding to mean substance intake values of up to 1349 mg/kg/day and 1745 mg/kg/day for males and females respectively. This study indicated the liver and thyroid to be the main target organs affected by TCPP. Effects observed included statistically significant increases in absolute and relative liver weights in males at all doses and females at the two highest doses, periportal hepatocyte swelling in high dose groups and mild thyroid follicular cell hyperplasia in males at all doses and females at the highest dose. Based on the increase in both absolute and relative liver weights, accompanied by mild thyroid follicular cell hyperplasia observed in males of all dose groups, a LOAEL of 52 mg/kg/day is derived. This study is taken forward in preference to the 28 -day & 2 -week study as it was a study of longer duration and the 28 -day study also showed the liver lesion with increased liver weight changes, accompanied by hepatocyte hypertrophy and changes in ALT activity.

Justification for classification or non-classification

This substance could not be presumed to have the potential to produce significant toxicity in human on the basis of evidence from repeated dose toxicity studies in experimental animals. Therefore, no classification is proposed for the repeated dose toxicity of TCPP.