Disodium 6-hydroxy-5-[(2-methoxy-4-sulphonato-m-tolyl)azo]naphthalene-2-sulphonate

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to microorganisms, other

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

Experimental data of test chemical

Justification for type of information:

Experimental data from read across substances.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

WoE report is prepared based on toxicity to microorganism studies:
WoE-2 and WoE-3

GLP compliance:

not specified

Analytical monitoring:

not specified

Details on sampling:

1. Concentrations: The test chemical conc. used for the study was 1000 mg/l (0.1%) and 10000 mg/l (1%)

Vehicle:

not specified

Test organisms (species):

other: 1. Paramecium caudatum, 2.Vibrio fisheri

Details on inoculum:

Method of cultivation: Food dye (test chemical) of 0.1% conc. was put in a hollow slide glass, and an equal volume of 0.04 M phosphate buffer, pH 7.0, was added. After 5 to 10 Paramecium caudatum were added, their survival times were measured microscopically. 30 to 40 test organism for each conc. were tested and the mean survival time and the death rate was calculated.

Test type:

static

Water media type:

freshwater

Total exposure duration:

20 min

Post exposure observation period:

1. After 20 mins, the mean survival time and the death rate was calculated.
2. 30.0 min exposure was provided to the microorganism

Test temperature:

2. 20 °C

Nominal and measured concentrations:

1. nominal concentrations
2. 500–5000 mg/L

Details on test conditions:

Test vessel: Hollow slide glass
No. of organisms per vessel: 30 to 40 test organism for each test conc. was taken for the study.

TEST CONCENTRATIONS
Test concentrations:1. 10000 mg/l (1%) and 1000 mg/l (0.1%) for WoE-2
2. 500–5000 mg/l with RO16 for WoE-3

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
After 20 mins, the mean survival time and the death rate was calculated for WoE-2.
With 30-min exposure time, EC50 value was determined for WoE-3

Reference substance (positive control):

not specified

Duration:

20 min

Dose descriptor:

other: greater than EC50

Effect conc.:

10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Remarks on result:

other: 1st study

Duration:

30 min

Dose descriptor:

EC50

Effect conc.:

1 375 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: inhibition % of light production

Remarks on result:

other: 2nd study

1.The mean survival time (in sec) of test organismParamecium caudatumwas determined to be 695 seconds.

 

Table 1:EFFECT OF FOOD DYES ON THE MEAN SURVIVAL TIME AND DEATH RATE OF Paramecium caudatum

 

Test chemical	Dye concentration
	1.0%		0.1%
	Mean survival time (sec)	Death rate (%)	Mean survival time (sec)	Death rate (%)
Test chemical	695	77.4	-*	3.3

-* indicates no deaths were observed for 20 minutes

2. The toxic effects were observed in similar ranges of dye concentrations in the flash luminescence test and protozoan tests, in spite of different endpoints involved. Compared to other compounds, the dyes used were not very efficient in inhibiting luminescence The effective dye concentrations exceeded those normally encountered in textile industry environmental pollution . Due to its simplicity and rapidity, the flash test was suitable for determination of toxicity of dye compounds, but its use for toxicity evaluation of dye containing diluted effluents could be limited because of the low sensitivity to these compounds.

Validity criteria fulfilled:

not specified

Conclusions:

1. The death rate of the test organism at 10000 mg/l was 77.4%. Therefore the Effective concentration causing more than 50% death of Paramecium caudatum is reported as 10000 mg/l.
2. With 30-min exposure of test chemical to microorganis, EC50 values was determine at 1375 mg/L for the test chemical.
Based on the above studies, chemical consider to be nontoxic.

Executive summary:

Various studies available for the test chemical were reviewed to determine the toxic nature of test chemical on the growth and other activity of microorganisms. The studies are as mentioned below:

To measure the effects of test substance on microorganisms a study was conducted on Paramecium caudatum (PC), a unicellular animal, which can be observed more readily and in far less time than that of small animals. P. Caudatum was maintained at 22°C on 0.15 % dried lettuce infusion and fed with Aerobacter aerogenes. Chemical was tested in 0.1% and 1% concentration. The test concentrations were put in a hollow slide glass, and an equal volume of 0.04 M phosphate buffer, pH 7.0, was added. After 5 to 10 test organisms were added, their survival times were measured microscopically. Thirty to forty test organisms for each concentration were tested by the same method, and the mean survival time and the death rate were calculated. The survival time was defined as the time required until death was observed for each concentration. Death was assumed to have occurred when there was no movement. The death rate was defined as the percentage of deaths observed during 20 minutes. The mean survival time (in sec) of test organism Paramecium caudatum was determined to be 695 seconds.  The death rate of the test organism at 10000mg/l was 77.4%. Therefore the Effective concentration causing more than 50% death of Paramecium caudatum was reported as 10000 mg/l.

First study was supported by the second study from peer reviewed journal which was conducted to determine the toxicity of test substance on microorganisms. The organisms (Vibrio fisheri) were exposed for 30 s and 30 min to test substance, and the peak luminescence value was obtained during the first 5s after adding the bacterial suspension to the sample. The test concentrations were 500–5000 mg/l with RO16. The results were calculated as the inhibition % of light production and expressed using the corresponding EC50 values. With 30-min exposure time, EC50 value was determined to be 1375 mg/L for the test chemical. Thus based on the EC50 value, chemical was considered to be nontoxic to the growth of microorganism.

Thus based on the overall studies for the test chemical was considered to be nontoxic and the toxicity ranges from the concentration 1375 mg/l - 10000 mg/l.

Description of key information

Various studies available for the test chemical were reviewed to determine the toxic nature of test chemical on the growth and other activity of microorganisms. The studies are as mentioned below:

 

To measure the effects of test substance on microorganisms a study was conducted on Paramecium caudatum (PC), a unicellular animal, which can be observed more readily and in far less time than that of small animals. P. Caudatum was maintained at 22°C on 0.15 % dried lettuce infusion and fed with Aerobacter aerogenes. Chemical was tested in 0.1% and 1% concentration. The test concentrations were put in a hollow slide glass, and an equal volume of 0.04 M phosphate buffer, pH 7.0, was added. After 5 to 10 test organisms were added, their survival times were measured microscopically. Thirty to forty test organisms for each concentration were tested by the same method, and the mean survival time and the death rate were calculated. The survival time was defined as the time required until death was observed for each concentration. Death was assumed to have occurred when there was no movement. The death rate was defined as the percentage of deaths observed during 20 minutes. The mean survival time (in sec) of test organism Paramecium caudatum was determined to be 695 seconds.  The death rate of the test organism at 10000mg/l was 77.4%. Therefore the Effective concentration causing more than 50% death of Paramecium caudatum was reported as 10000 mg/l.

 

First study was supported by the second study from peer reviewed journal which was conducted to determine the toxicity of test substance on microorganisms. The organisms (Vibrio fisheri) were exposed for 30 s and 30 min to test substance, and the peak luminescence value was obtained during the first 5s after adding the bacterial suspension to the sample. The test concentrations were 500–5000 mg/l with RO16. The results were calculated as the inhibition % of light production and expressed using the corresponding EC50 values. With 30-min exposure time, EC50 value was determined to be 1375 mg/L for the test chemical. Thus based on the EC50 value, chemical was considered to be nontoxic to the growth of microorganism.

Thus based on the overall studies for the test chemical was considered to be nontoxic and the toxicity ranges from the concentration 1375 mg/l - 10000 mg/l.

Key value for chemical safety assessment

EC50 for microorganisms:

10 000 mg/L

Additional information

Various studies available for the test chemical were reviewed to determine the toxic nature of test chemical on the growth and other activity of microorganisms. The studies are as mentioned below:

 

To measure the effects of test substance on microorganisms a study was conducted on Paramecium caudatum (PC), a unicellular animal, which can be observed more readily and in far less time than that of small animals. P. Caudatum was maintained at 22°C on 0.15 % dried lettuce infusion and fed with Aerobacter aerogenes. Chemical was tested in 0.1% and 1% concentration. The test concentrations were put in a hollow slide glass, and an equal volume of 0.04 M phosphate buffer, pH 7.0, was added. After 5 to 10 test organisms were added, their survival times were measured microscopically. Thirty to forty test organisms for each concentration were tested by the same method, and the mean survival time and the death rate were calculated. The survival time was defined as the time required until death was observed for each concentration. Death was assumed to have occurred when there was no movement. The death rate was defined as the percentage of deaths observed during 20 minutes. The mean survival time (in sec) of test organism Paramecium caudatum was determined to be 695 seconds.  The death rate of the test organism at 10000mg/l was 77.4%. Therefore the Effective concentration causing more than 50% death of Paramecium caudatum was reported as 10000 mg/l.

 

First study was supported by the second study from peer reviewed journal which was conducted to determine the toxicity of test substance on microorganisms. The organisms (Vibrio fisheri) were exposed for 30 s and 30 min to test substance, and the peak luminescence value was obtained during the first 5s after adding the bacterial suspension to the sample. The test concentrations were 500–5000 mg/l with RO16. The results were calculated as the inhibition % of light production and expressed using the corresponding EC50 values. With 30-min exposure time, EC50 value was determined to be 1375 mg/L for the test chemical. Thus based on the EC50 value, chemical was considered to be nontoxic to the growth of microorganism.

Thus based on the overall studies for the test chemical was considered to be nontoxic and the toxicity ranges from the concentration 1375 mg/l - 10000 mg/l.