2,2,6,6-tetramethyl-4-substituted-piperidinyl-1-oxy

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May 8th - 12th 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study in accordance with GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OECD 203

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Test material form:

other: Liquid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Samples of the test solutions in which the fish were exposed, were taken for analytical verification at the start of the definitive study, before and after renewal of solutions at 24, 48 and 72 hours and at the end of the 96 hour exposure period. Test substance specific analysis of each test concentration was carried out as soon as possible after sampling.

Test solutions

Details on test solutions:

A stock solution of 1000 mg/l was prepared and stirred to mix. Appropriate volumes of the stock solution were then made up to 10 litres by addition of dilution water to achieve the desired concentration. The test solutions were stirred to mix.

Test organisms

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

Supplier: Horn Mill Trout Farm, Oakham, UK. LE15 8BA
Mean length: 51.8 mm
Mean Weight: 1.14 g

Study design

Test type:

semi-static

Water media type:

freshwater

Total exposure duration:

96 h

Test conditions

Hardness:

227 mg CaCO3/L

Test temperature:

15 ±2 ºC

pH:

pH 8 ±0.1

Dissolved oxygen:

94-99%

Nominal and measured concentrations:

Nominal concentrations of 0 (control), 5, 10, 20, 40 and 80 mg/l were prepared

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

29.5 mg/L

Basis for effect:

mortality (fish)

Effect concentrations 2

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

14.8 mg/L

Basis for effect:

mortality (fish)

Effect concentrations 3

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

14.8 mg/L

Basis for effect:

mortality (fish)

Effect concentrations 4

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

14.8 mg/L

Basis for effect:

mortality (fish)

Effect concentrations 5

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

25.6 mg/L

Basis for effect:

mortality (fish)

Effect concentrations 6

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

4.07 mg/L

Details on results:

A mortality of 0% was observed in the control tank at the end of the test period.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 96 hour LC50 of Inhibitor AHM P500 was estimated to be 14.8 mg/l as determined by the Trimmed Spearman-Karber method. The highest no observed effect concentration (NOEC) based on mortalities for Inhibitor AHM P500 to Rainbow Trout was calculated as 4.07 mg/l, however when data for abnormal behaviour is included the NOEC was determined as less than 4.07 mg/l

Executive summary:

A GLP study according to OECD guideline 203 was performed in order to assess the effects of AHM P500 on Rainbow Trout (Oncorhynchus mykiss). The study was performed over a 96 hour period under semi-static conditions at concentrations of 0 (control), 5, 10, 20, 40 and 80 mg/L nominal concentrations determined in a preliminary study. Seven trout were placed in each of the control and test vessels, observations were performed on exposure and at 24, 48, 72 and 96 hours.

Some abnormal behaviour was noted during the test, symptoms included loss of equilibrium, postural instability, change in skin pigmentation and lethargy. Symptoms of abnormal behaviour were observed at all dose rates after 24, 48 72 and 96 hours and were believed to be an effect of Inhibitor AHM P500.

No mortality or abnormal behaviour was observed in the control tank.

The 96 hour LC50 of Inhibitor AHM P500 was estimated to be 14.8 mg/l as determined by the Trimmed Spearman-Karber method. The highest no observed effect concentration (NOEC) based on mortalities for Inhibitor AHM P500 to Rainbow Trout was calculated as 4.07 mg/l, however if data for abnormal behaviour is included the NOEC was determined as less than 4.07 mg/l