Benzoic acid, 4-(methylamino)-3-nitro-

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

Study period:

2011-10-04 to 2011-10-06

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4-(methylamino)-3-nitrobenzoic acid

EC Number:

609-904-5

Cas Number:

41263-74-5

Molecular formula:

C8 H8 N2 O4

IUPAC Name:

4-(methylamino)-3-nitrobenzoic acid

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

yes

Details on test solutions:

Prior to the test starting, 0.5 litre of a stock solution of 100 mg/L as test item was prepared by direct weighting into reconstituted water (0.0502 g of test item into 502 mL of reconstituted water). The obtained solution appeared orange and it showed orange insoluble grains, therefore it was sonicated for 15 minutes and then it was mixed by the mean of a magnetic stirrer for about 15 minutes in dark conditions to achieve the total solubilisation of test item.
After stirring, it was a clear and homogeneous solution.

Test organisms

Test organisms (species):

Daphnia magna

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Test temperature:

18.8 - 20.5°C

pH:

7.12 - 7.88

Dissolved oxygen:

6.48 - 6.81

Details on test conditions:

-20 animals per vessel (test item and negative control (reconstituted water))
-Test concentration based on range-finding study

Reference substance (positive control):

yes

Remarks:

Daphnia clone sensitivity check with potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

IC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

IC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

48 h

Dose descriptor:

other: IC0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Results with reference substance (positive control):

24 h IC50 = 1.02 mg/L

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

IC50 at 24 and 48 hours >100 mg/L

Executive summary:

The acute toxicity of the test item BIBR 1048 Aminoacido to Daphnia magna was determined in a 48-hour limit static test according to the OECD Guideline for Testing of Chemicals, No. 202 (2004) and to Council Regulation EC 440/2008 (C.2).

For this purpose, juvenile daphnids (< 24 hours old at initiation of the test) were exposed to an aqueous test medium containing the test item at the only concentration of 100.0 mg/L, corresponding to 99.1 mg/L, corrected for its purity, 99.1% w/w.

20 organisms for the test item solution and 20 organisms for negative control were exposed.

The exposed organisms were checked for immobilization 24 and 48 hours after test initiation.

The pH of the test media after preparation was 7.12 for test item solution and 7.40 for negative control. The incubation temperature was in the range 18.0 – 20.5 °C, thus within to the OECD recommended range (20 +- 2°C).

Light intensity during the 48 hours of test period was in the range 904 – 950 Lux, thus within the provided range 200-1500 Lux.

At the end of test period, in the negative control 0% of immobilization was observed and no daphnid was found to be trapped on the test water surface. These values comply with the validity criterion of the test, that provide a maximum immobilization and/or a maximum number of daphnids trapped into water surface of 10% in the negative control medium at the end of the test.

The obtained experimental results allowed to assess the IC0, the IC50 and the IC100 values at 24 and 48 h. The results, based on the nominal concentrations of the test item, were as reported in the result table above.

The IC50 values were determined from the Raw Data by the statistical analysis in comparison with the negative control (linear interpolation analysis) while IC0 and IC100 values at each observation time were directly extracted from the Raw Data.