4,4'-oxydi(benzenesulphonohydrazide)

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Principles of method if other than guideline:

NA

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Test concentrations were measured at the beginning (0 hr) and the end (72 hrs) of the study

Vehicle:

yes

Remarks:

DMF 0.1 mL/L

Details on test solutions:

Stock solution was prepared by diluting test chemical in dimethylformamide (100,000 mg/L). Test solutions were prepared by adding the corresponding amounts of stock solution into 1,000 mL of OECD medium. The concentration of solvent was 100 µL/L.

- Test Design
Nominal concentration: control, solvent control, 0.50, 0.82, 1.40, 2.20, 3.70, 6.10, and 10.0 mg/L
Initial cell density: 1 x 104 cells/mL
Number of Replicate: 3

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

Laboratory culture: ATCC culture medium 625 Gorham’s medium
Supplier: American Type Culture Collection, USA
Strain No.: ATCC 22662
Method of cultivation: Sterilization

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Post exposure observation period:

no

Hardness:

no data

Test temperature:

23 ± 2 °C

pH:

pH 7.7 ~ 7.8 at the beginning and pH 8.1 ~ 9.4 at the end of the test

Dissolved oxygen:

no data

Salinity:

NA

Nominal and measured concentrations:

Nominal
Concentration (mg/L) Measured Concentration (mg/L)
O hr % of Nominal 72 hrs % of Nominal
Control < 0.01 – < 0.01 –
Solvent control < 0.01 – < 0.01 –
0.50 0.45 90 < 0.01 < 2
0.82 0.70 85 < 0.01 < 2
1.40 1.17 84 < 0.01 < 1
2.20 1.83 83 < 0.01 < 1
3.70 3.11 84 0.04 1
6.10 5.20 85 0.04 1
10.0 8.21 82 0.08 1

Details on test conditions:

Light: 4,000 Lux, Light Periodicity: 24/0 (light/dark)
Shaking: 100 rpm

Reference substance (positive control):

not specified

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

0.35 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

0.059 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

NA

Results with reference substance (positive control):

no data

Reported statistics and error estimates:

Data analysis: The EC50 value (α=0.05) was calculated by linear regression analysis. The NOEC were determined by an analysis of variance (ANOVA), Williams test, subsequent to Bartlett test for homogenecity of variances. Statistical analyses were performed using Yukms Stalight #4 software (Yukms Corp., Tokyo) and all tests of significance were at α = 0.05, except Bartlett test, which was at α = 0.01.

Measured concentration of the test substance in test water under the static condition

Nominal Concentration (mg/L)	Measured Concentration (mg/L)
	O hr	% of Nominal	72 hrs	% of Nominal
Control	< 0.01	–	< 0.01	–
Solvent control	< 0.01	–	< 0.01	–
0.50	0.45	90	< 0.01	< 2
0.82	0.70	85	< 0.01	< 2
1.40	1.17	84	< 0.01	< 1
2.20	1.83	83	< 0.01	< 1
3.70	3.11	84	0.04	1
6.10	5.20	85	0.04	1
10.0	8.21	82	0.08	1

 

Cell density ofPseudokirchneriella subcapitata(ATCC 22662) during the test

Nominal Conc. (mg/L)	Measured Con. (mg/L)	Cell density (x 10^4cell/mL)
		0 hr	24 hrs	48 hrs	72 hrs
Control	Control	1	6.32± 0.48	45.54± 3.7	333.92± 39.23
Solvent control	Solvent control	1	6.78± 0.39	46.87± 0.96	322.92± 5.57
0.50	0.047	1	5.75± 0.31	42.54± 0.85	346.25± 26.41
0.82	0.059	1	5.48± 0.26	38.50± 1.33	313.92± 21.17
1.40	0.076	1	4.54± 0.38	34.77±2.59	279.59± 24.01
2.20	0.096	1	4.25± 0.38	32.54± 1.53	229.59± 23.46
3.70	0.35	1	3.24± 0.15	21.37± 1.31	171.59± 14.64
6.10	0.46	1	2.57± 0.40	15.44± 2.11	131.25± 5.69
10.0	0.81	1	2.22± 0.32	11.08± 2.67	81.15± 34.53

 

Growth inhibition (%) of Pseudokirchneriella subcapitata

Nominal Conc. (mg/L)	Measured Con. (mg/L)	Area under the curve (0~72hrs)
		Area	Inhibition(%)*
Control	Control	51,916,000± 5,707,000	-
Solvent control	Solvent control	51,027,000± 677,000	-
0.50	0.047	52,538,000± 2,999,000	-3.0
0.82	0.059	47,627,000± 2,780,000	6.7
1.40	0.076	42,386,000± 3,473,000	16.9**
2.20	0.096	35,780,000± 3,227,000	29.9**
3.70	0.35	25,896,000± 1,661,000	49.3**
6.10	0.46	19,472,000± 1,100,000	61.8**
10.0	0.81	12,331,000± 4,854,000	75.8**

 

Nominal Conc. (mg/L)	Measured Con. (mg/L)	Growth rates
		Rate (24~48 hrs)	Inhibition (%)* (24~48 hrs)	Rate (24~72hrs)	Inhibition (%)* (24~72 hrs)
Control	Control	1.94±0.01	-	0.0826±0.0010	-
Solvent control	Solvent control	1.93±0.01	-	0.0805±0.0016	-
0.50	0.047	1.95±0.03	-3.6	0.0854±0.0015	-6.1
0.82	0.059	1.92±0.02	-0.7	0.0843±0.0022	-4.7
1.40	0.076	1.88±0.03	-5.2	0.0858±0.0020	-6.6
2.20	0.096	1.81±0.03	-5.2	0.0831±0.0004	-3.2
3.70	0.35	1.71±0.03	2.5	0.0827±0.0009	-2.7
6.10	0.46	0.0748±0.0120	7.2	0.0821±0.0041	-2.0
10.0	0.81	0.0664±0.0051	17.6**	0.0735±0.0077	8.7**

Validity criteria fulfilled:

not specified

Conclusions:

72 hr-EC50 of OBSH to Pseudokirchneriella subcapitata was 0.35 mg/L based on the growth rate and the 72 hr-NOEC was 0.059 mg/L.

Executive summary:

The toxicity of OBSH towards aquatic algae (Pseudokirchneriella subcapitata) was tested applying the OECD Guideline no. 201. The study was conducted in compliance with GLP. The test was conducted under static test conditions with the following nominal test concentrations: control, solvent control, 0.50, 0.82, 1.40, 2.20, 3.70, 6.10, and 10.0 mg/L. DMF was used as solvent (0.1 mL/L). Based on the results obtained and the mean measired concentrations of the test an ErC50 (72h) of 0.35 mg/L was calculated. The corresponding NOEC was 0.059 mg/L.

Description of key information

A reliable ecotoxicity study (72 hr, static) to Pseudokirchnerella subcapitata was carried out according to OECD 201. The 72h-ECr50 (growth rate) was 0.35 mg/L and the NOErC (growth rate) was 0.059 mg/L (mean measured).

The findings are supported in another study with following results: 72h-ECr50 (growth rate) = 0.57 mg/L, NOErC (growth rate) = 0.21 mg/L (mean measured).

Key value for chemical safety assessment

EC50 for freshwater algae:

0.35 mg/L

EC10 or NOEC for freshwater algae:

0.059 mg/L