3-[(3-sulfanylbutanoyl)oxy]-2,2-bis{[(3-sulfanylbutanoyl)oxy]methyl}propyl 3-sulfanylbutanoate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 - 06 Mar 2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Testing Methods for New Chemical Substances (Japan) - 21/11/2003 No. 1121002

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: All test concentrations were measured at test start, before and after medium renewal and at test end.
- Sampling method: Test samples were taken from the middle layer of the test vessels.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test sample and dilution water were mixed to produce each nominal loading rate and stirred by magnetic stirrer for approx. 48 h. The solution was filtrated with a 0.4 µm glass fibre filter by suction. After the filtration, the filtrate was aerated for about 1 h under 24 °C in order to recover decreased dissolved oxygen concentration by suction and then used as test solution.

Test organisms (species):

Oryzias latipes

Details on test organisms:

TEST ORGANISM
- Common name: Medaka
- Source: Kurume Laboratory, Chemicals Evaluation and Research institute, 3-2-7 Miyanojin, Kurume-shi, Fukuoka 839-0801, Japan
- Age at study initiation (mean and range, SD): 3 months
- Length at study initiation (length definition, mean, range and SD): 2.3 ± 1.2 cm
- Feeding during test: none

ACCLIMATION
- Acclimation period: 24 days
- Acclimation conditions (same as test or not): same as test
- Type and amount of food: The test organisms were fed the feed mixture for carp (2C) until 24 hours before the start of exposure.
- Health during acclimation (any mortality observed): no mortality during the 7 days before test start

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

42 mg/L as CaCO3

Test temperature:

23.9 - 24.2 °C

pH:

7.5 - 7.9

Dissolved oxygen:

7.2 - 8.4 mg/L

Nominal and measured concentrations:

Nominal: 0, 0.8, 1.2, 2.0, 3.1, 5.0 mg/L
Measured: < LOQ, 0.12, 0.14, 0.25, 0.65, 0.51 mg/L (geometric mean)

Details on test conditions:

TEST SYSTEM
- Test vessel: Tank
- Type (delete if not applicable): closed
- Material, size, fill volume: glass, diameter 24 cm, depth 28 cm, approx. 4.9 L
- Aeration: none
- Renewal rate of test solution (frequency/flow rate): every 24 h
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): 1

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dechlorinated and aerated tap water
- Total organic carbon: 0.4 mg/L
- Particulate matter: < 1 mg/L
- Metals (mg/L): B 0.08, Al 0.042, Na 14.9, K 1.8, Ca 11.5, Mg 3.3, the other metals analysed were in the range from < 0.001 to < 0.01
- Pesticides: < 0.0001 to 0.0005 mg/L
- Chlorine: < 0.02 mg/L
- Alkalinity: 29 mg/L
- Ca/Mg ratio: 3.5:1
- Conductivity: 17.1 mS/m
- Culture medium different from test medium: no
- Intervals of water quality measurement: Oxygen, pH and temperature were measured at test start, before and after test solution renewal and at test end. Appearance of the test solutions was observed at test start and before test solution renewal.

OTHER TEST CONDITIONS
- Photoperiod: 16 h light/8 h dark, artificial light of white fluorescent lamp

EFFECT PARAMETERS MEASURED (with observation intervals if applicable)
- Mortality and abnormalities were observed 3, 24, 48, 72 and 96 h after the start of exposure.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.6
- Range finding study
- Test concentrations: Nominal concentrations 1.2, 3.6, 7.3, 12 mg/L
- Results used to determine the conditions for the definitive study: 1.2 mg/L: no mortality; 3.6 mg/L: 50% mortality after 48 h and 100% mortality after 96 h; 7.3 mg/L: 25% mortality after 24 h and 100% mortality after 48 h; 12 mg/L: 100% mortality after 24 h. A semi-static regime with 24 h renewal intervals was chosen because it was shown that the measured concentration of the test item solutions decreased after 48 h.

Reference substance (positive control):

yes

Remarks:

CuSO4 x 5 H2O

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

0.16 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

other: filtered test solution

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: Swimming at the water surface, light body colour and reduced activity was observed at 0.65 and 0.51 mg/L measured concentrations after 48 h of exposure.
- Observations on body length and weight at test end: Total length 2.5 ± 0.076 cm, body weight 0.13 ± 0.011 g (mean ± SD, n = 7)
- Mortality of control: None
- Other adverse effects control: None
- Appearance of test solutions: Clear and colourless throughout the test period

Results with reference substance (positive control):

- Results with reference substance valid? Yes.
- Test date: 20 Oct - 24 Oct 2008
- LC50 (96 h): 0.34 mg/L (range of laboratory data: 0.14 - 0.97 mg/L)

Reported statistics and error estimates:

Results were estimated using a program running on MS Excel, developed by our laboratory. The LC50 for 48 and 72 h were calculated by Probit analysis. The LC50 (96 h) was calculated by Binomial test.

Sublethal observations / clinical signs:

Table 1: Cumulative mortality of O. latipes exposed to the test item

Measured concentration (mg/L)	Cumulative mortality (%)
	3 h	24 h	48 h	72 h	96 h
Control	0	0	0	0	0
0.12	0	0	0	0	0
0.14	0	0	0	0	29
0.25	0	0	0	86	100
0.65	0	14	86	100	100
0.51	0	0	57	86	100

Table 2: Additional effect concentrations

Exposure duration	LC50 (mg/L)	95% CL (mg/L)	Statistics	Reference values
				LL50 (mg/L)	Statistics
24 h	> 0.65	-	-	> 5.0	-
48 h	0.49	0.012 – 0.60	Probit analysis	2.6	Binomial test
72 h	0.23	0.16 – 0.32	Probit analysis	1.7	Binomial test
96 h	0.16	-	Binomial test	1.4	Binomial test

Validity criteria fulfilled:

yes

Conclusions:

This study was conducted as a test in order to estimate LC50 of the test item for the test organisms below the solubility of the test item in dilution water. As a result, the LC50 (96 h) based on the measured concentration was 0.16 mg/L, the LC50 (96 h) based on the nominal loading rate was 1.4 mg/L.

Executive summary:

This study was conducted as a test in order to estimate LC₅₀ of the test item for the test organisms below the solubility of the test item in dilution water. As a result, the LC50 (96 h) based on the measured concentration was 0.16 mg/L, the LC50 (96 h) based on the nominal loading rate was 1.4 mg/L.

Description of key information

LC50 (96 h) = 0.16 mg/L for Oryzias latipes (OECD 203)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.16 mg/L

Additional information

For the short-term toxicity of the substance to fish one key study with Medaka (Oryzias latipes) according to OECD 203 and GLP is available (Showa Denko, 2009). The fish were exposed to analytically verified concentrations of the substance under semi-static conditions. After 96 h of exposure, the cumulative mortality was 29% at 0.14 mg/L and 100% at 0.25 mg/L measured concentrations. The LC50 (96 h) was determined to be 0.16 mg/L (measured).