Tetrakis(hydroxymethyl)phosphonium sulphate(2:1)

Short-term toxicity to fish

Description of key information

EPA OPP 72-1, OECD Guideline 203, GLP, key study, validity 1:
96h-LC50 (Oncorhynchus mykiss) = 71 mg/L (measured, as main ingredient). 
THPS is considered as harmful to fish.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

71 mg/L

Marine water fish

Marine water fish

Effect concentration:

65 mg/L

Additional information

Six studies are available to assess the short-term toxicity of the active substance THPS to fish. These studies were performed with 75% THPS aqueous solution under semi-static or flow-through conditions, with freshwater and seawater species. The results were expressed in test item concentrations and converted in active ingredient (100% THPS).

There are two studies of reliability 1 (Jenkins, 1991a; Jenkins, 1991b) and two studies of reliabiity 3 on freshwater species (Hill, 1984b; Douglas, 1987); one study of reliability 1 on a brackish species (Boeri, 1995a) and one study of reliability 2 on a marine water species (Douglas, 1989). Whatever the test conditions, the valid studies (of reliability 1 or 2) show 96 h-LC50 values ranging between 65 (brackish species) and 74 mg a.i./L (freshwater species). The valid study with the lowest LC50 value has been defined as the key study (Jenkins, 1991a).

Results are expressed in the table below (as main ingredient):

Test method	Species	Endpoint / Type of test	Exposure	Reliability	Flag	Results (LC50 (95% CL), mg/L)	Reference
EPA OPP 72-1 and OECD Guideline 203	Oncorhynchus mykiss (freshwater species)	Mortality / Acute	Semi-static, 96h	1	KS	71 (58-105)	Jenkins, 1991a
EPA OPP 72-1 and OECD Guideline 203	Lepomis macrochirus (freshwater species)	Mortality / Acute	Semi-static, 96h	1	SS	74 (51-157)	Jenkins, 1991b
EPA OPP 72-3 and OECD Guideline 203	Cyprinodon variegatus (brackish species)	Mortality / Acute	Flow through, 96h	1	SS	72 (41-110)	Boeri, 1995a
Ministry of Agriculture, Fisheries and Food, UK	Pleuronectes platessa (marine species)	Mortality / Acute	Semi-static, 96h	2	SS	65 (56-75)	Douglas, 1989
No guideline but similar to OECD Guideline 203	Oncorhynchus mykiss (freshwater species)	Mortality / Acute	Flow through, 96h	3	SS	74 (66-85)	Hill, 1984b
OECD Guideline 203	Lepomis macrochirus (freshwater species)	Mortality / Acute	Flow through, 96h	3	SS	14 (11-18)	Douglas, 1987

In conclusion, THPS is considered harmful to fish.