Tris(2-butoxyethyl) phosphate

Short-term toxicity to fish

Description of key information

OECD Guideline 203, EU Method C1, no-GLP, key study, validity 2: 96h-LC50 = 24 mg/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

24 mg/L

Additional information

Available data on short-term toxicity to fish

Four studies were recorded for the endpoint short-term toxicity to fish. An overview of this dataset is provided in the table below:

Method	Species	Basis for effect	Endpoint	Effect concentration	Reliability	Reference
OECD 203 EC Method C.1	Oncorhynchus mykiss	Mortality	96h-LC50 96h-NOEC	=24 mg/L (n) =10 mg/L (n)	2	Wetton PM & Handley JW (1998)
OPTS EPA 560/6-002 (1982)	Pimephales promelas	Mortality	96h-LC50 96h-NOEC	=16 mg/L (n) =7.8 mg/L (n)	2	Sousa JV & Holling JP (1984)
JIS K 0102-1986-71	Oryzias latipes	Mortality	48h-LC50 (10°C) 48h-LC50 (20°C) 48h-LC50 (30°C)	=44 mg/L (n) =27 mg/L (n) =6.8 mg/L (n)	2	Tsuji S et al (1986)
OECD 203	Pimephales promelas	Mortality	96h-LC50	=11.2 mg/L (m)	2	Geiger DL et al (1986)

n: nominal concentration - m: measured concentration

Sensitivity of fish to TBEP exposure

For the three species, the toxicity parameters (96h-LC50, 48h-LC50) were in the same order of magnitude ie from 10 mg/L to 100 mg/L. The short-term toxicity to fish of TBEP is increased by temperature (Tsuji et al., 1986) which is a conventional pattern.

Selection of the key study

The study of Wetton and Handley (1998) was flagged as key study for this endpoint.

Conclusion

Based on the available dataset, tris(2 -butoxyethyl) phosphate would be classified as harmful to freshwater fish in accordance with the classification system of EU (Directive 67/548/EC).