6-[methyl(phenylsulphonyl)amino]hexanoic acid, compound with 2,2',2''-nitrilotriethanol (1:1)

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

other: Study conducted on formulated product containing the registered substance

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study was conducted by a GLP accredited laboratory using OECD Testing Guideline 203. Study was conducted on a formulated product containing the registered substance.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

Nominal concentrations of the test material of 100, 177.8, 316.2, 562.3 and 1000 mg/l were prepared in artificial seawater. Artificial seawater (Coral Reef, Kent Sea Salt, Red Sea Fish Pharm) was prepared. The test material was described as soluble in water. After addition to seawater the sample dispersed well throughout the test vessels. No rangefinder test was conducted for this study. The definitive test range was determined via other in-house testing and from information presented on the MSDS.

Test organisms (species):

other: Scophthalamus maximus (juvenile turbot)

Details on test organisms:

The test species were supplied by France Turbot, L'Epine, France. Juvenile turbot were received on 10th November 2004 free of malformations and in good health and assigned a batch number. Animals were fed and maintained as detailed in the test laboratories Standard Operating Procedures (SOP). Stock juvenile turbot were held in artificial seawater maintained at 15°C ± 2°C by a chiller unit and aerated via air diffusers attached to the laboratory air supply system. Feeding was stopped when juvenile turbot were transferred to test tanks 24 hours before the start of the tests.

Test type:

semi-static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

The mean temperature in the 1000 mg/l test group was 15.2°C, and for the control group the mean was 15.2°C. Information was not provided for the other test groups.

pH:

The mean pH in the 1000 mg/l test group was 8.29, and for the control group the mean was 7.94. Information was not provided for the other test groups.

Dissolved oxygen:

The mean dissolved oxygen in the 1000 mg/l test group was 97.2%, and for the control group the mean was 97.9%. Information was not provided for the other test groups.

Salinity:

The mean salinity in the 1000 mg/l test group was 32.4 ‰, and for the control group the mean was 32.5‰. Information was not provided for the other test groups.

Nominal and measured concentrations:

Nominal concentrations of the test material of 100, 177.8, 316.2, 562.3 and 1000 mg/l were prepared in seawater.

Details on test conditions:

Single replicates of 10 litres at each test concentration and control media were prepared. Seven animals were added to each test vessel and exposures conducted under semi-static conditions with replacement of media every 48 hours. The test duration was 96 hours at a nominal temperature of 15°C ± 1.5°C. Dissolved oxygen, pH, temperature and salinity values were recorded at 24 hour intervals during the study.

Reference substance (positive control):

yes

Remarks:

dichlorophenol (DCP)

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

All animals in the control vessels survived the 96 hour test period.

Results with reference substance (positive control):

The DCP test result for the most recent Turbot batch tested was >0.6 mg/l

Sublethal observations / clinical signs:

Mortality data for juvenile turbot exposed to control and test media containing the test material

Test material concentration (mg/l)	Status	Exposure Period (hours)
		0	24	48	72	96
0	Alive	7	7	7	7	7
	Dead	0	0	0	0	0
100	Alive	7	7	7	7	7
	Dead	0	0	0	0	0
177.8	Alive	7	7	7	7	7
	Dead	0	0	0	0	0
316.2	Alive	7	7	7	7	7
	Dead	0	0	0	0	0
562.3	Alive	7	7	7	7	7
	Dead	0	0	0	0	0
1000	Alive	7	7	7	7	7
	Dead	0	0	0	0	0

 

DCP Result: The DCP test result for the most recent Turbot batch tested was >0.6 mg/l

The NOEC after 96 hours was 1000 mg/l. The LOEC after 96 hours was >1000 mg/l.

Validity criteria fulfilled:

not specified

Conclusions:

The 96 hour LC50 was found to be >1000 mg/l. No mortality was observed in the study.

Executive summary:

The acute toxicity of the test material (a formulated product containing a structurally similar substance to the registered substance) to fish was determined in accordance with the OECD Guideline for Testing of Chemicals 203. The species used for the test was Scophthalmus maximus (juvenile turbot), which was tested under semi-static conditions for 96 hours. Nominal concentrations of 100, 177.8, 316.2, 562.3 and 1000 mg/l of the test material were prepared. The 96 hour LC₅₀ was found to be >1000 mg/l. No mortality was observed in the study. As no upper limit was provided for the LC₅₀ of the test material it was not possible to calculate the toxicity of the registered substance included in the formulated product. However, as the product contains approximately 50% (44.7%) of the N-methyl salt, and 50% of 1000 mg/l is 500 mg/l it is considered unlikely that the N-methyl salt is toxic to fish.

Description of key information

The 96 hour LC50 of a formulated product containing the registered substance was >1000 mg/l. As no upper limit was provided for the LC50 of the test material it was not possible to accurately calculate the toxicity of the registered substance included in the formulated product. However, as the product contains approximately 50% (44.7%) of the N-methyl salt, and 50% of 1000 mg/l is 500 mg/l it is considered unlikely that the N-methyl salt is toxic to fish.

Key value for chemical safety assessment

Marine water fish

Marine water fish

Dose descriptor:

LC50

Effect concentration:

500 mg/L

Additional information

The acute toxicity of the a formulated product containing the registered substance to fish was determined in accordance with the OECD Guideline for Testing of Chemicals 203. The species used for the test was Scophthalmus maximus (juvenile turbot), which was tested under semi-static conditions for 96 hours. The 96 hour LC₅₀ of the test material was >1000 mg/l. As no upper limit was provided for the LC₅₀ of the test material it was not possible to accurately calculate the toxicity of the registered substance included in the formulated product. However, as the product contains approximately 50% (44.7%) of the N-methyl salt, and 50% of 1000 mg/l is 500 mg/l it is considered unlikely that the N-methyl salt is toxic to fish. In addition, an equivalent study was conducted using a formulated product containing a structurally similar substance (6 -[(p-Tosyl)amino]hexanoic acid, compound with 2,2',2''-nitrilotriethanol (1:1) (Tosyl salt)) to the registered substance. A nominal concentration of 23 mg/l of the test substance was used in the limit test. After 96 hours exposure in this study the LC₅₀ value was determined to be >23 mg/l i.e. higher than the maximum concentration tested. As no upper limit was provided for the LC₅₀ of the test material it was not possible to calculate the toxicity of the registered substance included in the formulated product. Read-across between the registered substance and the test substance (a formulated product containing Tosyl salt) is considered justified owing to the structural similarity of the two substances. Both are salts of a carboxylic acid and triethanolamine. The acid components are structural isomers and differ only in the position of a single methyl group in the N-methyl salt. This is not expected to change the bioavailability of the substances, and both substances have shown similarity in the results of other physical endpoints such as water solubility.