2-Propanol, 1,3-bis[(3-methyl-2-buten-1-yl)oxy]-

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:

2020-12-21 to 2020-12-25

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

2019-06-18

Deviations:

not specified

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 100, 55.6, 30.9, 17.1, 9.53 mg/L and controls at the start of exposure and every 24 hours
- Sampling method: The test solution for measurement was taken out from the test vessel.
(except continuous temperature)

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Stirring
- Controls: Dechlorinated tap water
- Test concentration separation factor: 1.8
- Other relevant information: Dilution water (3 L) was placed in preparation container, and the test sample (316µL*) was added using a microsyringe. The mixture was stirred with a magnetic stirrer and dissolved to prepare the stock solution of 100 mg/L. The stock solution was prepared at 6 L (3 L x 2). Required volume of the stock solution was mixed with dilution water in the test
vessel and stirred to prepare the test solution. In the test level of 100 mg/L, the stock solution was used as the test solution without treatment. The stock solution and the test solution were
newly prepared for each renewal. *: 0.300 g [= 316µL x density (0.949 g/mL at 25° C)]

Test organisms (species):

Oryzias latipes

Details on test organisms:

TEST ORGANISM
- Common name: Medaka
- Source: in-test facility production
- Age at study initiation (mean and range, SD): hatching date: November 9, 2020 (age at the start of exposure; one-month-old)
- Length at study initiation (length definition, mean, range and SD): 1 - 2 cm

ACCLIMATION
- Acclimation period: 11 days (December 10, 2020 - December 21, 2020)
- Acclimation conditions (same as test or not): same as test conditions
- Type and amount of food during acclimation: Newly hatched Artemia nauplii, saturation volume
- Feeding frequency during acclimation: daily
- Health during acclimation (any mortality observed): 0% (during 7 days before the start of exposure)

FEEDING DURING TEST
None

Test type:

semi-static

Water media type:

freshwater

Remarks:

Dechlorinated tap water

Limit test:

no

Total exposure duration:

96 h

Hardness:

45.1 mg CaCO3/L

Test temperature:

Thermometer of glass stick type: 24.0 - 24.3 °C
Thermo recorder (continuously-measured): 23.7-24.5 °C

pH:

7.7 - 8.0

Dissolved oxygen:

8.3 - 8.8 mg/L

Salinity:

Not reported

Conductivity:

7.4 mS/m of dilution water

Nominal and measured concentrations:

100, 55.6, 30.9, 17.1, 9.53 mg/L as nominal concentration (a geometric series with a factor of 1.8); renewal after 48 h

The results of this study were estimated based on the nominal concentrations since the measured concentrations of the test item in the test solutions of all exposure levels were maintained within the range of 80-120% of the nominal concentrations during exposure.

Details on test conditions:

TEST SYSTEM
- Test vessel: 3L glass tank (diameter: 16 cm, depth: 17 cm)
- Aeration: Conducted gently
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dechlorinated tap water
- Total organic carbon: < 0.5 mg/L
- Particulate matter: suspended solid: < 1 mg/L
- Metals: all < 0.1 mg/L
- Pesticides: all < 0.002 mg/L
- Chlorine: < 0.02 mg/L
- Alkalinity: 17 CaCO3 mg/L

OTHER TEST CONDITIONS
- Adjustment of pH: None
- Photoperiod: Room light, 16-hour light/8-hour dark
- Light intensity: illuminance 540-1000 lx

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.8

Reference substance (positive control):

no

Remarks:

A 96-hour acute toxicity study of a reference substance with the test organism was periodically conducted.

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Observations on body length and weight:
Total length 1.7 ± 0.1 cm (1.6 - 1.9 cm)
Body weight 0.046 ± 0.006 g (0.041 - 0.058 g)
- Mortality of control: 0%
- Other adverse effects control: None
- Abnormal responses: Observed abnormal responses during exposure were at the surface, complete loss of equilibrium, reduced activity, and extended abdomen.
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: The test solutions in all test levels were colorless and clear at the start of exposure and before the renewal.
- Effect concentrations exceeding solubility of substance in test medium: None

Results with reference substance (positive control):

- Results with reference substance valid? yes
- LC50: 0.22 mg/L
- Other: Reference substance Copper (II) sulfate pentahydrate

Reported statistics and error estimates:

The LC50 was estimated as "> the highest test concentration" since the mortality over 50%
in the range of the test concentrations was not observed. The results of this study were
estimated based on the nominal concentrations since the measured concentrations of the test item in the test solutions of all exposure levels were maintained within the range of 80-120% of the nominal concetrations during exposure.

Sublethal observations / clinical signs:

Table 1    Cumulative mortality

 

Nominal concentration (mg/L)	Cumulative mortality(%)
	2 hours	5 hours	24 hours	48 hours	54 hours	72hours	78 hours	96 hours
Control	0	0	0	0	0	0	0	0
9.53	0	0	0	0	0	0	0	0
17.1	0	0	0	0	0	0	0	0
30.9	0	0	0	0	0	0	0	0
55.6	0	0	0	0	0	0	0	0
100	0	0	0	0	0	0	0	0

Table 2    Observed abnormal response

 

 

Nominal concentration (mg/L)	Result of observation (Left column: Number of affected fish/Total survival number, Right column: Symptom detail)
	2hours		5 hours		24 hours		48 hours
Control	0/7	N	0/7	N	0/7	N	0/7	N
9.53	0/7	N	0/7	N	0/7	N	0/7	N
17.1	0/7	N	0/7	N	0/7	N	0/7	N
30.9	0/7	N	0/7	N	1/7	AS(l)	0/7	N
55.6	3/7	AS(3)	0/7	N	3/7	AS(3)	3/7	AS(3)
100	7/7	AS(4) CLE(4)	717	AS(7) CLE(2)	717	AS(7) CLE(2)	717	AS(7) CLE(2)
		RA(7)		RA(7)		RA(7)		RA(5)

 

Nominal concentration (mg/L)	Result of observation (Left column: Number of affected fish/Total survival number, Right column: Symptom detail)
	54 hours		72hours		78 hours		96 hours
Control	0/7	N	0/7	N	0/7	N	0/7	N
9.53	0/7	N	0/7	N	0/7	N	0/7	N
17.1	0/7	N	0/7	N	0/7	N	0/7	N
30.9	0/7	N	0/7	N	0/7	N	1/7	AS(l)
55.6	4/7	AS(4)	3/7	AS(3)	3/7	AS(3)	3/7	AS(3)
100	7/7	AS(7) CLE(2)	717	AS(7) CLE(2)	717	AS(7) CLE(2)	717	AS(7) CLE(3)
		RA(5)		RA(5)		RA(5)		RA(5)EA(3)

N: Normal (No abnormal response)

Value in parentheses expresses the number of individuals that showed the symptom. Abbreviation of symptoms

AS: At the surface

CLE: Complete loss of equilibrium RA: Reduced activity

EA: Extended abdomen

 

Table 3-1 Dissolved oxygen concentration of test solution

Nominal concentration (mg/L)	At the start	24 hours	48 hours		72 hours	At the end
			Old	New
Control	8.8	8.5	8.6	8.7	8.4	8.7
9.53	8.8	8.5	8.5	8.7	8.3	8.5
17.1	8.8	8.4	8.5	8.7	8.4	8.5
30.9	8.8	8.4	8.5	8.7	8.3	8.5
55.6	8.8	8.5	8.4	8.7	8.3	8.5
100	8.8	8.5	8.4	8.7	8.3	8.6

Old: before the renewal

New: after the renewal Unit: mg/L

Table 3-2 pH of test solution

Nominal concentration (mg/L)	At the start	24 hours	48 hours		72 hours	At the end
			Old	New
Control	7.9	7.9	7.9	7.9	7.9	7.7
9.53	7.9	7.9	7.9	7.9	7.9	7.8
17.1	7.9	7.9	7.9	8.0	7.9	7.9
30.9	7.9	7.9	8.0	8.0	7.9	7.9
55.6	7.9	8.0	8.0	8.0	7.9	7.9
100	7.9	8.0	8.0	8.0	7.9	8.0

Old: before the renewal

New: after the renewal

Table 3-3    Temperature of test solution

Nominal concentration (mg/L)	At the start	24 hours	48 hours		72 hours	At the end
			Old	new
Control	24.2	24.3	24.1	24.2	24.3	24.0
9.53	24.2	24.3	24.1	24.2	24.3	24.0
17.1	24.2	24.3	24.1	24.2	24.3	24.0
30.9	24.2	24.3	24.1	24.1	24.3	24.1
55.6	24.2	24.3	24.1	24.1	24.3	24.1
100	24.2	24.3	24.1	24.1	24.3	24.1

Old: before the renewal

New: after the renewal

Unit: °C

Table 4    LC₅₀ to Medaka

Exposure duration	LC50 (mg/L)	95% confidence limits (mg/L) (Slope of regression line)	Statistical procedure used for determination ofLC50
24-hour	>100	- (-)	-
48-hour	>100	- ( - )	-
72-hour	>100	- ( - )	-
96-hour	>100	- (-)	-

-: Not obtained

Validity criteria fulfilled:

yes

Remarks:

Number of dead fish in all exposure levels and control at the end of exposure was 0, which met the criterion for the validity of the test (i.e. not exceed one fish in the control).

Conclusions:

This study was conducted in order to estimate the LC50 on the test organisms. Although toxic symptoms were confirmed in a concentration-dependent manner, no mortality was observed in all exposure levels. As a are result, the 96-hour LC50 was > 100 mg/L. The test item concentrations in the test solutions were maintained within 80-120% of the nominal concentrations during exposure and the environmental conditions were within the suitable range. Therefore, it is concluded that this study complied with the applied test guideline.

Description of key information

This study was conducted in order to estimate the LC50 on the test organisms. Although toxic symptoms were confirmed in a concentration-dependent manner, no mortality was observed in all exposure levels. As a are result, the 96-hour LC50 was > 100 mg/L. The test item concentrations in the test solutions were maintained within 80-120% of the nominal concentrations during exposure and the environmental conditions were within the suitable range. Therefore, it is concluded that this study complied with the applied test guideline.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Remarks:

96-hour LC50 > 100 mg/L