3-hydroxy-4'-methoxy-2-naphthanilide

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:

2017/07/26-2017/11/12

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

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:

3-hydroxy-4'-methoxy-2-naphthanilide

EC Number:

202-190-2

EC Name:

3-hydroxy-4'-methoxy-2-naphthanilide

Cas Number:

92-79-5

Molecular formula:

C18H15NO3

IUPAC Name:

3-hydroxy-4'-methoxy-2-naphthanilide

Test material form:

solid

Details on test material:

- Batch number: 1283282001
- Purity: 98.8%
- Appearance/colour: solid/yellow-brown
- Expiry date: 30 April 2019

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Sampling method: analytical samples taken at 0 hours (initial value) and 48 hours from aged test solutions
- Fortified samples: stock solution of the test item (1000 mg/L, purity not considered) was prepared in acetonitrile. Further stock solutions (1620 mg/L and 2130 mg/L, purity not considered) were prepared in acetone. A dilution (10 mg/L) was prepared from the 2130 mg/L stock solution. A further dilution (10 mg/L) was prepared in acetonitrile from the 1620 mg/L stock solution. The dilutions (10 mg/L) were used for fortification of 0.0300 mg/L recovery samples. For 16.0 mg/L recovery samples the stock solution 1000 mg/L was used.
- Sample storage (before test): all samples were stored deep frozen until they were transferred to the analytical laboratory

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone: straus, clone 5
- Feeding during test: no feeding during test
- Feeding of culture (before test): three times a week with single cell green algae
- Main test: freshly hatched daphnids less than 24 hours old were used

Study design

Test type:

static

Water media type:

other: Elendt M4

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

232 mg/L as CaCO3

Test temperature:

20.0 – 21.8 °C

pH:

7.62 – 7.98

Dissolved oxygen:

≥ 7.2 mg/L

Nominal and measured concentrations:

Nominal concentrations: 100, 31.3, 9.77, 3.05, 0.954 mg/L and control
Test item loading rates (geometric mean measured): 1.80 mg/L (corresponding to 100), the other values were only monitored (not reported) and for the control it was not determined

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beakers
- Material, size, headspace, fill volume: 100 mL capacity filled with 50mL of test solution
- No. of organisms: 20 daphnids per test item loading rates (4 replicates of 5 animals each)
- No. of treatment groups: 6 (5 dose rates of the test item and a control)

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M4
- Culture medium different from test medium: same as Elendt M4

OTHER TEST CONDITIONS
- Exposure to light: none

EFFECT PARAMETERS MEASURED: Immobilisation

RANGE-FINDING STUDY
- Test concentrations: control, 100, 10, 1 and 0.1mg/L
- Sampling points : after 24h and 48h of exposure
- Results used to determine the conditions for the definitive study:
- After 24 hours of exposure no immobilisation above the allowed control immobilisation was observed in the control and up to and including 100 mg/L.
- After 48 hours of exposure no immobilisation was observed in the control and up to and including 10.0 mg/L. 15 % immobilisation was observed at the highest test item loading rate of 100 mg/L.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate, tested at 1.00 and 2.00 mg/L with 20 test organisms per test concentration, at around the same time period as the study

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 1.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 1.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Test concencentrations: 1 and 2 mg/L (20 organisms per test concentration)
- Relevant effect levels: the results indicate an EC50 (24h) of the reference substance below 1mg/L. The reuslts are in accordance with the requirements of the OECD guideline 202.

Any other information on results incl. tables

Summary of biological results:

a) Results of the main test, 24h values

	nominal test item loading rate [mg/L]
	Control	0.954	3.05	9.77	31.3	100
	immobilised daphnids after 24 h
Group 1	0	2	0	0	0	0
Group 2	0	0	0	0	1	0
Group 3	0	0	1	0	0	0
Group 4	0	0	0	0	0	0
Σ	0	2	1	0	1	0
%	0	10	5	0	5	0

b) Results of the main test, 48h values

	nominal test item loading rate [mg/L]
	Control	0.954	3.05	9.77	31.3	100
	immobilised daphnids after 48 h
Group 1	0	2	0	0	0	0
Group 2	0	0	0	0	2	0
Group 3	0	0	1	0	0	0
Group 4	0	0	0	0	0	0
Σ	0	2	1	0	2	0
%	0	10	5	0	10	0

Determined concentration of test substance:

Test item loading rate		Test item	Sampling	Test item found		Test item concentration
nominal [mg/L]		nominal [mg/L]	[h]	[mg/L]	% of nominal	measured [mg/L]*
Control	0		0 fresh	n.d.	-	-
			48 aged	n.d.	-
100			0 fresh	15.3	15	1.80
			48 aged	0.215	0.215

* based on geometric mean of measured concentrations

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 48-hour EC50 for Daphnia magna is > 1.8 mg/L (measured, geom. mean).

Executive summary:

The short-term toxicity to Daphnia magna was determined according to OECD 202 guideline with no deviations. The study was conducted under static conditions. The daphnids were exposed over a period of 48 hours to different nominal concentrations of 100, 31.3, 9.77, 3.05, 0.954 mg/L and a control. The measured concentration is 1.80 mg/L (corresponding to 100), the other values were only monitored (not reported) and for the control it was not determined.

The validity criteria were fulfilled.

The EC50 value was determined to be > 1.80 mg/L (measured, geom. mean).