Ethyl 4-[[(methylphenylamino)methylene]amino]benzoate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From November 15, 2016 to January 03, 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes

Test organisms (species):

Daphnia magna

Details on test organisms:

- Source: National Chiayi University Freshwater Biological Resource Center

Test type:

semi-static

Water media type:

freshwater

Total exposure duration:

48 h

Test temperature:

18-22 °C

Nominal and measured concentrations:

0.08, 0.18, 0.40, 0.88, 1.94, 4.27, 9.39, 20.66, 45.45 and 100.00 mg/L

Details on test conditions:

- Test volume: 30 mL
- Aeration: None
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Photoperiod: 16-hr light: 8-hr dark

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

2.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

In range-finding test, the 0% of control organisms were immobilised at the end of the test and the dissolved oxygen concentration of control and test groups during the test was 8.44-8.72 mg O2/L. The initial pH measurements did not differ from the final measurements by more than 1.5 units in each test. The results of the range-finding test showed that EC₅₀ was 26.49 mg/L.

In definitive test, the results showed below:

 

Table 1. The numbers immobilized forthe definitive teston day 1 and 2

Group (mg/L)		Numbers of no immobilised	Numbers of activity immobilised	Numbers of discoloration	Numbers of trapping at surface of water
Solvent control group	0.00	20	0	0	0
Test group	100.00	0	20	0	0
	45.45	15	3	0	2
	20.66	14	5	0	1
	9.39	15	5	0	0
	4.27	15	5	0	0
	1.94	19	1	0	0
	0.88	19	1	0	0
	0.40	19	1	0	0
	0.18	20	0	0	0
	0.08	20	0	0	0
Solvent control group	0.00	20	0	0	0
Test group	100.00	0	20	0	0
	45.45	9	7	0	4
	20.66	6	13	0	1
	9.39	4	15	0	1
	4.27	4	16	0	0
	1.94	14	6	0	0
	0.88	16	4	0	0
	0.40	17	3	0	0
	0.18	18	2	0	0
	0.08	19	1	0	0

Table 2. The percentages immobilized for the definitive test

Group (mg/L)		Percentages immobilized (%)
		Day 0	Day 1	Day 2
Solvent control group	0.00	0.00	0.00	0.00
Test group	100.00	0.00	100.00	100.00
	45.45	0.00	25.00	55.00
	20.66	0.00	30.00	70.00
	9.39	0.00	25.00	80.00
	4.27	0.00	25.00	80.00
	1.94	0.00	5.00	30.00
	0.88	0.00	5.00	20.00
	0.40	0.00	5.00	15.00
	0.18	0.00	0.00	10.00
	0.08	0.00	0.00	5.00

Table 3. EC50 and 95% confidence interval for the definitive test

Parameter	Concentration
	(mg/L)
EC50	2.70
95% confidence interval-lower	1.55
95% confidence interval-upper	7.02

Table 4. Temperature, dissolved oxygen and pH value for the definitive test

Group (mg/L)		Day 0			Day 2
		Temperature (°C)	Dissolved oxygen (mg/L)	pH value	Temperature (°C)	Dissolved oxygen (mg/L)	pH value
Solvent control group	0.00	19.0	8.62 ± 0.05	7.37 ± 0.03	20.0	8.65 ± 0.02	7.46 ± 0.05
Test group	100.00		8.71 ± 0.10	7.43 ± 0.02		8.72 ± 0.06	7.47 ± 0.02

Validity criteria fulfilled:

yes

Conclusions:

According to OECD 202 test method, the 48-hr EC50 of the test substance was 2.70 mg/L.

Executive summary:

This test using the procedures outlined in the SuperLab Study Plan for M62-151100163002EN which is based on the SOP for the OECD 202 (SOPE-505) and OECD 202 (OECD, 2004). The results of this OECD 202 test for the test substance show that all validity criteria were met. The EC50 was 26.49 mg/L in the range-finding test, so the definitive test was conducted. The concentrations were 0.08, 0.18, 0.40, 0.88, 1.94, 4.27, 9.39, 20.66, 45.45 and 100.00 mg/L in the definitive test. Under the conditions of this test, the 48-hr EC50 of test substance was 2.70 mg/L.

Description of key information

The 48-hr EC50 of the test substance was 2.70 mg/L for Daphnia magna (OECD TG202).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

2.7 mg/L

Additional information

In both range-finding and definitive test, not more than 10 % of the Daphnia were immobilised in the control and the dissolved oxygen concentration of control and test groups at the end of the test was ≥3 mg O₂/L. All test validity criteria were met. The pH of the test solutions was within the ranges outlined in the OECD 202 test guideline. Based on the results derived from the range-finding test, there should conduct definitive test. Therefore, the concentrations set between 0.08 and 100.00 mg/L in the definitive test. Under the conditions of this test, the 48-hr EC50 of the test substance was 2.70 mg/L.