5-nitroisophthalic acid

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

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 from structurally similar read across analogue

Justification for type of information:

Experimental data from structurally similar read across analogue

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: refer principle below

Principles of method if other than guideline:

WoE report is prepared based on short term toxicity to aquatic invertebrates studies : WoE-2 and WoE-3

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

not specified

Details on test solutions:

WoE-2: The stock solution 200 mg/l was prepared by dissolving test chemical in reconstituted water. Test solutions of required concentrationas were prepared by mixing the stock solution of the test sample with reconstituted test water.

WoE-3
Stock solution of test chemical by addition of the test chemical to MilliQ water in a measuring flask and ultrasonic bath until a total solubilization of the chemical was achieved.

Test organisms (species):

Daphnia magna

Details on test organisms:

WoE-2:
TEST ORGANISM
- Common name: Water flea
- Strain: Straus
- Source: Own breeding at University of Chemistry and Technology, Prague
- Age at study initiation (mean and range, SD): The animals used for the test shall be less than 24 h old and should not be first brood progeny
- Feeding during test: No feeding


WoE-3
Common name: water flea
Age: less than 24 h

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

± 1 hr

Test temperature:

WoE-2: 20±1°C

pH:

WoE-2: Control: 7.8 (Change to 7.6 during test)
WoE-3: 7.8 ± 0.2.

Dissolved oxygen:

WoE-2: higher than 8.4 mg/L at the end of test

Nominal and measured concentrations:

WoE-2: 0, 6.2, 12.4, 25, 50, 100, 200 mg/l.
WoE-3: 5 to 8 concentrations

Details on test conditions:

WoE-2:
TEST SYSTEM
- Test vessel: 50 ml glass vessel
- fill volume: 25 ml
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
Natural water (surface or ground water), reconstituted water or dechlorinated tap water are acceptable as culturing and dilution water if D. magna survives in it for the duration of the culturing, acclimation and testing without showing signs of stress. Waters in the range pH 6 to pH 9, with hardness between 140 mg/l and 275 mg/l (as CaCO3) are recommended.
As an example, the preparation of dilution water meeting the requirements is described below.
Dissolve known quantities of reagents in water. The dilution water prepared shall have a pH of 7.8 ± 0.5, a hardness of (225 ± 50) mg/l (expressed as CaCO3), a molar Ca + Mg ratio close to 4 + 1 and a dissolved oxygen concentration above 7 mg/l.

Prepare the solutions specified below:
- Calcium chloride solution: Dissolve 117.6 g of calcium chloride dihydrate (CaCl2.2H2O) in water (4.2) and make up to 1 l with water (4.2).
- Magnesium sulfate solution: Dissolve 49.3 g of magnesium sulfate heptahydrate (MgSO4.7H2O) in water (4.2) and make up to 1 l with water (4.2).
- Sodium bicarbonate solution: Dissolve 25.9 g of sodium bicarbonate (NaHCO3) in water (4.2) and make up to 1 l with water (4.2).
- Potassium chloride solution: Dissolve 2.3 g of potassium chloride (KCI) in water (4.2) and make up to 1 l with water (4.2).

Mixing
Mix 2.5 ml of each of the four solutions and make up to 1 l with water.
The dilution water shall be aerated until the dissolved oxygen concentration has reached saturation and the pH has stabilized. If necessary, adjust the pH to 7.8 ± 0.5 by adding sodium hydroxide (NaOH) solution or hydrochloric acid (HCI). The dilution water prepared in this way shall not be further aerated before use.

- Sodium hydroxide solution, e.g. [NaOH] : 1 mol/l.
- Hydrochloric acid, e.g. [HCl] : 1 mol/l.

Reference substance:
Dissolve 600 mg of potassium dichromate (K2Cr2O7) in water and make up to 1 l with water (4.2).

OTHER TEST CONDITIONS
- Adjustment of pH: no adjustment done
- Photoperiod: No - Darkness
- Light intensity:

CALCULATION:
EC50 was calculated using non linear regression by the software Prism 4.0


WoE-3:
- No. of organisms per vessel: 5 animals per replicates
- No. of vessels per concentration (replicates): four replicates per concentrations
- No. of vessels per control (replicates): 8 replicates of control
- Biomass loading rate: 5 animals in 20 mL test medium

RANGE-FINDING STUDY
Range-finding tests covering several decades of concentrations and definitive tests to establish EC values and the corresponding 95% confidence intervals

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (K2Cr2O7)

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

96.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Without concentration 200 mg/l

Remarks:

95% CI was 68.6 - 136.4 mg/l

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

71.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL: 42.2-120.7 mg/l

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

103 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence (85.0; 123)

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

6.04 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % confidence (—; 2.81)

Duration:

24 h

Dose descriptor:

EC10

Effect conc.:

32.6

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence 4.02; 52.8

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

121 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % confidence interval (103; 141)

Results with reference substance (positive control):

WoE-2:
- Results with reference substance valid
- EC50: 0.76 mg/L (24 hours)

Reported statistics and error estimates:

WoE-2:
EC50 was calculated using non linear regression by the software Prism 4.0

WoE-3
probit analysis

WoE-2:

pH value:

Sample concentration (mg/l)	6.2	12.4	25.0		50.0	100.0	200.0
Start of the test	7.6	7.6		7.2	6.8	6.2	4.1
The end of the test	7.7	7.6		7.4	7.0	6.9	4.0

Validity criteria fulfilled:

not specified

Conclusions:

By applying weight of evidence approach the EC 50 value of test chemical is expected to be in range from 96.7 mg/L to 103 mg/L after exposure to Daphnia magna for 48 h. This range EC 50 value indicates that the test chemical is likely to be nonhazardous to aquatic invertebrates and cannot be classified as per CLP regulation. Since the test chemical is readily biodegradable in nature.

Executive summary:

Short term toxicity to aquatic invertebrates of test chemical was determined by using weight of evidence approach by using different experimental data from its structurally similar read across analogues and their results are summarized below

 

In first study an experiment was conducted to determine the short term toxicity of test chemical to aquatic invertebrates by using OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). The test organisms used in this study was Daphnia magna. The stock solution 200 mg/l of test chemical was prepared by dissolving test chemical in reconstituted water. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with reconstituted test water. The nominal concentrations of test chemical used were 0, 6.2, 12.4, 25, 50, 100, 200 mg/l. The test system used was 50 mL glass vessel and 5 test organisms were used per vessel in 4 replicates per concentration. The experiment was carried out in static system in freshwater and various concentrations of test chemical exposed to Daphnia magna for 48 h and at temperature 20±1°C. The reference substance used was

Potassium dichromate. EC50 was calculated using nonlinear regression by the software Prism 4.0

After 48 h exposure of test chemical to Daphnia magna the effective concentration at which 50 % immobility observed EC50 value was determined to be 96.7 mg/L (95% CI was 68.6 - 136.4 mg/l). The EC50 value of reference substance was observed to be 0.76 mg/L (24 hours).

 The EC 50 value indicates that the test chemical is likely to be nonhazardous to aquatic invertebrates. Since the test chemical is readily biodegradable in nature.

 

 

Another study was reviewed from Environmental Toxicology and Chemistry, 2003 in this an experiment was conducted to determine the short term toxicity of test chemical to aquatic invertebrates by using ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea)). ). The test organisms used in this study was Daphnia magna. The Stock solution of test chemical was prepared by addition of the test chemical to MilliQ water in a measuring flask and ultrasonic bath until a total solubilization of the chemical was achieved. Range-finding experiments covered several decades of concentrations and then definitive tests was established EC values and the corresponding 95% confidence intervals. 5-8 different nominal concentration of test chemical were used in the study. The experiment was carried out in static system in freshwater and different concentrations of test chemical exposed to Daphnia magna for 48 h. The number of organisms used per vessel was 5 with 4 replicates of each concentrations. The 6 replicates of control was also used. The reference substance used was Potassium dichromate. After 48 h exposure the EC 50 value was determined by using probit analysis method.

The EC10 and EC50 value was determined to be 6.04 mg/L and 103 mg/L (95% confidence interval  (85.0; 123)) respectively after exposure of test chemical to Daphnia magna for 48 h.The EC10 and EC50 value was determined to be 32.6 mg/L and 121 mg/L (95 % confidence interval (103; 141)) respectively after exposure of test chemical to Daphnia magna for 24 h.

By considering EC50 value after exposure for 48 h the test chemical is considered to be nontoxic to aquatic invertebrates and cannot be classified as per CLP regulation.

 

By considering results of both the studies mentioned above and applying weight of evidence approach the EC 50 value of test chemical is expected to be in range from 96.7 mg/L to 103 mg/L after exposure to Daphnia magna for 48 h.   This range EC 50 value indicates that the test chemical is likely to be nonhazardous to aquatic invertebrates and cannot be classified as per CLP regulation. Since the test chemical is readily biodegradable in nature.

Description of key information

By applying weight of evidence approach the EC 50 value of test chemical is expected to be in range from 96.7 mg/L to 103 mg/L after exposure to Daphnia magna for 48 h. This range EC 50 value indicates that the test chemical is likely to be nonhazardous to aquatic invertebrates and cannot be classified as per CLP regulation. Since the test chemical is readily biodegradable in nature.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

103 mg/L

Additional information

Short term toxicity to aquatic invertebrates of test chemical was determined by using weight of evidence approach by using different experimental data from its structurally similar read across analogues and their results are summarized below

 

In first study an experiment was conducted to determine the short term toxicity of test chemical to aquatic invertebrates by using OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). The test organisms used in this study was Daphnia magna. The stock solution 200 mg/l of test chemical was prepared by dissolving test chemical in reconstituted water. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with reconstituted test water. The nominal concentrations of test chemical used were 0, 6.2, 12.4, 25, 50, 100, 200 mg/l. The test system used was 50 mL glass vessel and 5 test organisms were used per vessel in 4 replicates per concentration. The experiment was carried out in static system in freshwater and various concentrations of test chemical exposed to Daphnia magna for 48 h and at temperature 20±1°C. The reference substance used was

Potassium dichromate. EC50 was calculated using nonlinear regression by the software Prism 4.0

After 48 h exposure of test chemical to Daphnia magna the effective concentration at which 50 % immobility observed EC50 value was determined to be 96.7 mg/L (95% CI was 68.6 - 136.4 mg/l). The EC50 value of reference substance was observed to be 0.76 mg/L (24 hours).

 The EC 50 value indicates that the test chemical is likely to be nonhazardous to aquatic invertebrates. Since the test chemical is readily biodegradable in nature.

 

 

Another study was reviewed from Environmental Toxicology and Chemistry, 2003 in this an experiment was conducted to determine the short term toxicity of test chemical to aquatic invertebrates by using ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea)). ). The test organisms used in this study was Daphnia magna. The Stock solution of test chemical was prepared by addition of the test chemical to MilliQ water in a measuring flask and ultrasonic bath until a total solubilization of the chemical was achieved. Range-finding experiments covered several decades of concentrations and then definitive tests was established EC values and the corresponding 95% confidence intervals. 5-8 different nominal concentration of test chemical were used in the study. The experiment was carried out in static system in freshwater and different concentrations of test chemical exposed to Daphnia magna for 48 h. The number of organisms used per vessel was 5 with 4 replicates of each concentrations. The 6 replicates of control was also used. The reference substance used was Potassium dichromate. After 48 h exposure the EC 50 value was determined by using probit analysis method.

The EC10 and EC50 value was determined to be 6.04 mg/L and 103 mg/L (95% confidence interval  (85.0; 123)) respectively after exposure of test chemical to Daphnia magna for 48 h.The EC10 and EC50 value was determined to be 32.6 mg/L and 121 mg/L (95 % confidence interval (103; 141)) respectively after exposure of test chemical to Daphnia magna for 24 h.

By considering EC50 value after exposure for 48 h the test chemical is considered to be nontoxic to aquatic invertebrates and cannot be classified as per CLP regulation.

 

By considering results of both the studies mentioned above and applying weight of evidence approach the EC 50 value of test chemical is expected to be in range from 96.7 mg/L to 103 mg/L after exposure to Daphnia magna for 48 h.   This range EC 50 value indicates that the test chemical is likely to be nonhazardous to aquatic invertebrates and cannot be classified as per CLP regulation. Since the test chemical is readily biodegradable in nature.