2-nitrophenyl acetate

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

yes

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Principles of method if other than guideline:

There was a deviation from temperature in the definitive test. The temperature was not in the prescribed range (20 ± 2°C) during test. Prescribed range was exceeded by about 0.4 °C. This increase of temperature was minimal and takes only short period of time. (3 hours).

This deviation does not impact the integrity of study.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Acetic acid, 2-nitrophenyl ester

IUPAC Name:

Acetic acid, 2-nitrophenyl ester

Constituent 2

Reference substance name:

2-nitrophenyl acetate

EC Number:

210-233-1

EC Name:

2-nitrophenyl acetate

Cas Number:

610-69-5

Molecular formula:

C8H7NO4

IUPAC Name:

2-nitrophenyl acetate

Test material form:

solid: crystalline

Details on test material:

- Name of test material (as cited in study report): 2-Nitrophenyl Acetate

- Physical state: solid light yellow
- Analytical purity: 95 % w/w

- Impurities (identity and concentrations):
Phenol <5.0 % (w/w)
2,4-dinitrophenol <5.0 % (w/w)
2,6-dinitrophenol <5.0 % (w/w)
Acetic acid <1.0 % (w/w)
Water <5.0 % (w/w)
2-nitrophenol <5.0 % (w/w)

- Lot/batch No.: 201408
- Expiration date of the lot/batch: unlisted

- Storage condition of test material: The test substance will be stored in dry room in dark in
closed container at the room temperature

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Details on test solutions:

For holding and culturing of the daphnia the M4 medium was used (according to Annex 2 of the EU method C.2 and according to Annex 3 of the OECD TG 202).
For test was used dilution water (according to Annex 2 of the EU method C.2 and according to Annex 3 of the OECD TG 202). Dilution water was prepared just before the test by admixing 2.5 mL of stored solutions A, B, C and D into 1 000 mL of deionized water.
A. 117.6 g CaCl2·2H20 in 1 L of deionized water
B. 49.3 g MgSO4·7H2O in 1 L of deionized water
C. 25.9 g NaHCO3 in 1 L of deionized water
D. 2.3 g KCl in 1 L of deionized water
The dilution water is saturated by oxygen by the aeration at temperature of 18 – 22 °C.
It should be of pH 7.8  0.2, values measured in this study were 7.7 in preliminary test and 8.0 in the semi-static definitive test.
The content of sum Ca + Mg ions should have the value of 2.50 +- 0.1 mmol·L-1, values measured in this study were 2.54 mmol·L-1 in the preliminary test and 2.58 mmol·L-1 in the semi-static definitive test.
Measured values meet the requirements.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM

- Strain: Straus
- Source: own breeding

- Method of breeding:
- Feeding during test
- Food type: mixture of algae


ACCLIMATION
- Acclimation period: 48 h
- Acclimation conditions (same as test or not): dilution water

Study design

Test type:

semi-static

Water media type:

freshwater

Total exposure duration:

48 h

Test conditions

Test temperature:

20 +- 2°C, with a variation of +- 1°C at each individual test

pH:

7.7 - 8.0

Dissolved oxygen:

higher than 3 mg·L-1, 7.6 - 8.0 mg.L-1

Nominal and measured concentrations:

The definitive semi-static test was performed with a range of nominal concentrations from 0.2 mg·L-1 to 21.3 mg·L-1.

Test solution 1 (prepared 05.08.2015)
Stock solution of test substance: 10.05 mg·100 mL-1
Test concentration: 21.3, 9.7, 4.4, 2.0, 0.9, 0.4 and 0.2 mg·L-1
Conductivity of deionized water: 1.66 μS·cm-1
pH of dilution water: 8.0
Oxygen content of dilution water: 7.7 mg·L-1
Content of (Ca+Mg) in dilution water: 2.58 mmol·L-1

Test solution 2 (prepared 06.08.2015)
Stock solution of test substance: 9.91 mg·100 mL-1
Test concentration: 21.3, 9.7, 4.4, 2.0, 0.9, 0.4 and 0.2 mg·L-1
Conductivity of deionized water: 1.66 μS·cm-1
pH of dilution water: 8.0
Oxygen content of dilution water: 7.7 mg·L-1
Content of (Ca+Mg) in dilution water: 2.58 mmol·L-1

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

11.06 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

not specified

Remarks on result:

other: 10.41-11.71

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.84 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

not specified

Remarks on result:

other: 0.43-1.25

Effect concentrations 3

Duration:

24 h

Dose descriptor:

EC0

Effect conc.:

0.4 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 4

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

0.3 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 5

Duration:

24 h

Dose descriptor:

EC100

Effect conc.:

> 13.1 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 6

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

13.1 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

The time weighted mean concentrations were used for all evaluations and results because was demonstrated that the concentrations of the test substance were not satisfactorily maintained within ± 20 percent of measured initial concentration throughout the test.
The EC0 and EC100 values are identified by direct observation.

Results with reference substance (positive control):

The sensitivity of the test species and correctness of test performance is periodically verified in six-month period by testing with the reference substance, potassium dichromate.
The results of the verification test with K2Cr2O7, carried out in period from 15.04. to 17.04. 2015 are the following:
24 hour – EC50 = 1.95 mg·L-1(95% confidence limit: 1.75 – 2.15 mg·L-1)
48 hour – EC50 = 0.86 mg·L-1(95% confidence limit: 0.70 – 1.02 mg·L-1)

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The test substance, 2-Nitrophenyl Acetate, was tested in acute immobilisation test on Daphnia magna.

Executive summary:

The test substance, 2-Nitrophenyl Acetate, was tested in acute immobilisation test on Daphnia magna.

The test was performed according to method C.2 – Daphnia sp. Acute Immobilisation Test, Council Regulation (EC) No. 440/2008, published in O.J.L 142, 2008.

The preliminary test was performed in range of the test substance nominal concentrations 1 – 100 mg·L-1. The analytical results showed, that the test substance 2-Nitrophenyl Acetate was not stable in dilution water in the conditions of the test. Based on toxicity and instability of the test substance found in preliminary test, the definitive test was performed as semi-static in appropriate concentration range.

The semi-static definitive test was performed in range of the test substance nominal concentrations of 0.2 – 21.3 mg·L-1. The test solutions were renewed after 24 hours. The test substance concentrations was measured at the beginning, after 24 hours (before and after renewal) and at the end of the test.

There is stated in the guideline that, if evidence is available to demonstrate that the concentration of the test substance has been satisfactorily maintained within ± 20 percent of the nominal or measured initial concentration throughout the test, the results can be based on nominal or measured initial values.

Because concentrations of the test substance have not been satisfactorily maintained within ± 20 percent of initial concentration throughout the test, time-weighted mean concentrations were used for all evaluations and results.

Test results:

24 hour–EC50 = 11.1 mg·L-1 (time-weighted mean concentration)

(95% confidence limit: 10.4 – 11.7 mg·L-1)

48 hour–EC50 = 0.8 mg·L-1 (time-weighted mean concentration)

(95% confidence limit: 0.4 – 1.3 mg·L-1)

24 hour–EC0 = 0.4 mg·L-1 (time-weighted mean concentration)

48 hour–EC0 = 0.3 mg·L-1 (time-weighted mean concentration)

24 hour–EC100 > 13.1 mg·L-1 (time-weighted mean concentration)

48 hour–EC100 = 13.1 mg·L-1 (time-weighted mean concentration)