4-(4-isopropoxyphenylsulfonyl)phenol

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 1990-11-15 to 1990-12-11

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Samples were taken at start of the test, after 24 hours and after 48 hours. Samples of all test concentrations (abt. 5 mL) were diluted with acetonitrile and 10 µL of the solution was injected into the HPLC system.

Vehicle:

yes

Details on test solutions:

For the 40; 25; 16; 10 mg/L groups, the aliquot of the test substance was individually weighed, dissolved with a small amount of dimethylformamide (DMF, contained 1 % of Tween 80) and mixed with dilution water in a flask. Each flask was stoppered and immersed in an ultrasonic bath for 5 min and the solution was divided into 4 vessels. The solution for the 10 mg/L group was successively diluted with the dilution water to make the 6.3 and 4 mg/L groups. Final concentration of DMF (included Tween 80) was 0.1 mL/L. Nominal concentrations of D-8 in the test solutions were 40; 25; 16; 10; 6.3 and 4 mg/L.

Test organisms (species):

Daphnia sp.

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia sp.
- Strain: Daphnia similis (Claus)
- Source: Tokai Regional Fisheries Research Laboratory
- Age at study initiation: More than 6 hours and less than 24 hours
- Weight at study initiation: not indicated
- Length at study initiation: 0.86 ± 0.05 mm (Mean ± SD)
- Method of breeding: not indicated
- Feeding during test: none

ACCLIMATION
- Acclimation period: not indicated

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

24 and 48 hours

Hardness:

80 mg/L

Test temperature:

21.7 - 21.8 °C

pH:

8.0

Dissolved oxygen:

8.3 mg/L

Nominal and measured concentrations:

Nominal concentrations: 40; 25; 16; 10; 6.3; 4.0 mg/L
Actual concentrations (after 24 hrs): 33.5; 21.5; 15.4; 9.95; 5.92; 3.80 mg/L

Details on test conditions:

160 healthy individuals were selected, randomly assigned to each vessel and exposed for 48 hours.
No. of groups: 6 exposed; a vehicle control and an untreated control group.
Each group contained 20 individuals.

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

19 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95 % CI: 17 - 21 mg/L

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

13 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95 % CI: 12 - 14 mg/L

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

17 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CI: 16 - 19 mg/L

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

12 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CI: 11 - 13 mg/L

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

17 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95 % CI: 16 - 19 mg/L

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

13 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95 % CI: 12 - 15 mg/L

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

16 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CI: 15 - 18 mg/L

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

12 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CI: 11 - 14 mg/L

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

6.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Deaths and toxic sign (immobilisation) were observed in the 10 mg/L group and higher exposed groups. Neither toxic signs nor deaths were found in the 6.3 and 4 mg/L groups and both control groups.

Reported statistics and error estimates:

Calculation of LC50 (nominal and actual concentrations) was made with Probit method.

A few small particles were observed in the test solutions for the 40 and 25 mg/L groups before being divided into each 4 vessels. These particles were adhesive and adhered immediately to the inner surface of the flask, and could not be dispersed into the water.

There was no marked difference between nominal and actual concentrations in the 16 mg/L and the lower groups at the start of the test. But the actual concentrations of the 25 and 40 mg/L groups were lower than the nominal concentrations of these groups (78 and 74 % in the 25 and 40 mg/L groups, respectively).

The actual concentrations were maintained in all the exposed groups during the test. It is therefore considered that D-8 is stable in the water and more amount of solvent or dispersant than the limit of 0.1 mg/L is necessary for making the test substance suspend well.

Table 1: Actual concentration of D-8

Nominal Concentration (mg/L)	Group No.	Actual concentration (mg/L)^1)
		Start	24 h^2)	48 h^2)
40	1	29.5	33.5 (114)	-
25	2	19.6	21.6 (110)	23.4 (119)
16	3	15.9	15.4 (97)	16.7 (105)
10	4	9.95	9.46 (95)	10.2 (103)
6.3	5	5.92	6.05 (102)	6.40 (108)
4	6	3.80	3.85 (101)	4.06 (107)

 

1): Figures in the parentheses indicates the ratio (%): (actual concentration after 24 h or 48 h/actual concentration at the start)*100

2): Figures are mean values of 4 vessels except the value of 48 h in Group 2. (All the daphnids in 3 vessels of Group 2 died after 24 h.)

Table 2: Mortalities and Number of Dead Daphnids Exposed to D-8

Test substance	Concentration (mg/L)	No. of daphnids	No. of deaths^1)		Mortality (%) after 48 hours
			24 hours	48 hours
D-8	40	20	20	20	100
	25	20	19	20	100
	16	20	4 (3)	18 (1)	90
	10	20	0	1 (2)	5
	6.3	20	0	0	0
	4	20	0	0	0
Vehicle control	-^2)	20	0	0	0
Untreated control	-	20	0	0	0

 

1): Figures in the parentheses indicate the number of daphnids showing immobilization.

2): DMF (included 1 % Tween 80) = 0.1 mL/L (= 0.094 g/L)

Validity criteria fulfilled:

yes

Conclusions:

D-8 was tested for toxicity to Daphnia in a 48-h static immobilisation test and the EC 50 value was determined to be 12 mg/L.

Executive summary:

D-8 was tested for acute toxicity to Daphnia in a 48-h static test with six test and two control groups according to OECD 202. The nominal test substance concentrations were 40; 25; 16; 10; 6.3 and 4.0 mg/L. Deaths and toxic sign (immobilisation) were observed in the 10 mg/L group and higher exposed groups. Neither toxic signs, nor deaths were observed in the 6.3 and 4 mg/L groups and both control groups. The EC50 value for 48-h exposure was found to be 12 mg/L.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

from 1990-05-14 to 1990-06-04

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

The test substance was weighed, dissolved in a small amount of Dimethylformamide (DMF, including 1 % Tween 80) and suspended with dilution water. This suspension was successively diluted with dilution water to make 6 concentrations of 100, 63, 40, 25, 16, and 10 mg/L.

Test organisms (species):

Daphnia sp.

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia sp.
- Strain: Daphnia similis (Claus)
- Source: Takai Regional Fisheries Research Laboratory
- Age at study initiation: More than 6 hours and less than 24 hours
- Weight at study initiation: not indicated
- Length at study initiation: 0.95 ± 0.06 mm (Mean ± SD)
- Method of breeding: not indicated
- Feeding during test: none

ACCLIMATION
- Acclimation period: not indicated

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

24 h

Post exposure observation period:

24 hours

Hardness:

80 mg/L

Test temperature:

21.5 - 21.7 °C

pH:

7.8

Dissolved oxygen:

8.3 mg/L

Nominal and measured concentrations:

Nominal concentrations: 100; 63; 40; 25; 16 and 10 mg/L
No measured concentrations.

Details on test conditions:

160 healthy individuals were selected, randomly assigned to each vessel and exposed for 24 hours.
No. of groups: 6 exposed; a vehicle control and an untreated control group.
Each group contained 20 individuals.

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

21 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95 % CI: 19 - 24 mg/L

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

20 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CI: 18 - 23 mg/L

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Deaths and toxic sign (immobilisation) were observed in the 16 mg/L and higher dosed groups. Neither toxic signs, nor deaths were found in the 10 mg/L and both control groups.

Reported statistics and error estimates:

Calculation of LC50 was perfomed using the Probit method.

Table: Mortalities and Number of Dead Daphnids Exposed to D-8

Test substance	Concentration (mg/L)	No. of daphnids	No. of deaths^1)	Mortality (%) after 24 hours
D-8	100	20	20	100
	63	20	20	100
	40	20	20	100
	25	20	14 (1)	70
	16	20	4 (1)	20
	10	20	0	0
Vehicle control	-^2)	20	0	0
Untreated control	-	20	0	0

 

1): After 24 hours, figures in the parentheses indicate the number of daphnids showing immobilisation

2): DMF = 1mL/L, Tween 80 = mL/L.

Validity criteria fulfilled:

yes

Conclusions:

In a 24-h toxicity test to Daphnia sp. an EC50 of 21 mg/L for D-8 was determined.

Executive summary:

D-8 was tested for acute toxicity to Daphnia in a 24-h static test with six test and two control groups according to EU Method C.2. The nominal test substance concentrations were 100, 63, 40, 25, 16 and 10 mg/L. Deaths and toxic sign (immobilisation) were observed in the 16 mg/L and higher dosed groups. Neither toxic signs, nor deaths were found in the 10 mg/L and both control groups. The EC50 value for 24-h exposure was found to be 21 mg/L.

Description of key information

D-8 was tested for toxicity to Daphnia in a 48-h static immobilisation test and the EC50 value was determined to be 12 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

12 mg/L

Additional information

Key study - OECD 202

D-8 was tested for acute toxicity to Daphnia in a 48-h static test with six test and two control groups according to OECD 202. The nominal test substance concentrations were 40; 25; 16; 10; 6.3 and 4.0 mg/L. Deaths and toxic sign (immobilisation) were observed in the 10 mg/L group and higher exposed groups. Neither toxic signs, nor deaths were observed in the 6.3 and 4 mg/L groups and both control groups. The EC50 value for 48-h exposure was found to be 12 mg/L.

Supporting study - EU Method C.2

D-8 was tested for acute toxicity to Daphnia in a 24-h static test with six test and two control groups according to EU Method C.2. The nominal test substance concentrations were 100, 63, 40, 25, 16 and 10 mg/L. Deaths and toxic sign (immobilisation) were observed in the 16 mg/L and higher dosed groups. Neither toxic signs, nor deaths were found in the 10 mg/L and both control groups. The EC50 value for 24-h exposure was found to be 21 mg/L.