N-[2-[(2-chloro-4,6-dinitrophenyl)azo]-5-(diethylamino)-4-methoxyphenyl]acetamide

Endpoint summary

Description of key information

Short-term toxicity to aquatic invertebrates

EL50 (48h) > 5 mg/l

Toxicity to aquatic plants and cyanobacteria

ErL50 (72 h) > 5 mg/l

Additional information

No studies on "aquatic toxicity" are available for the substance in itself.

Nevertheless studies have been conducted with a analogue molecules (Similar Substance 02 and 04). Further information are reported in the Read Across justification attached to section 13.

Short-term toxicity to aquatic invertebrates

In the key study the substance (Similar Substance 02) was tested on Daphnia magna (STRAUS), according to OECD guideline 202. The effects of a saturated solution with a nominal loading of 5.00 mg/L of the test item were determined under static conditions over a period of 48 hours. The saturated solution was visually clear during the exposure period. Twenty daphnids, divided into 4 replicates with 5 daphnids each, were exposed to the saturated solution and the control.

The concentration of the test item was analytically verified via HPLC-DAD in fresh media at the start of the exposure (0 hours) in the saturated solution and in the control.

The measured concentration in the saturated solution was < LOD (LOD = 0.05 mg/L with a S/N ratio of 3) at the start of the exposure (0 hours).Therefore, analytical monitoring at the end of the exposure was waived and the test item concentration was considered to be below the LOD in the 48-hours old media, too.

According to OECD Guidance Document No 23 (2000), if an effect cannot be detected in a test with a saturated solution, the result has to be reported as no toxic effects at saturation. Exposures are expressed in terms of the original concentration of the test item in water at the start of the mixing period (loading rate).

The validity criteria of the test guideline were fulfilled.

 

EL_{10 / 50 / 100}-Values(based on the nominal loading of the test item)

Effect values	Test duration [hours]	Disperse Violet93.1 Nominal loading level of the test item [mg/L]
EL10 / 50 / 100	24	> 5.00
	48	> 5.00

 

In the supporting study the substance (Similar Substance 04) was tested for its acute toxicity toDaphnia magna,according to the OECD guideline 202, at 0.9, 1.9, 4.3, 9.4, 21, 45, 100 mg/l.The EC50 calculated in this test was greater than 100 mg/l.

Toxicity to aquatic algae and cyanobacteria

The toxicity of the test substance (Similar Substance 02) to the unicellular freshwater green alga Pseudokirchneriella subcapitata was determined according to the principles of OECD 201.The aim of the study was the determination of NOEL, LOEL, EL₁₀, EL₂₀- and EL₅₀-values of growth rate and yield over a period of 72 hours.

The study was conducted under static conditions with an initial cell density of 6839 cells/mL. A saturated solution with a nominal loading of 5.00 mg test item/L was prepared with dilution water 24 ± 1 hour prior to the start of the exposure. An appropriate amount of the test item was weighed out. The saturated solution was stirred for 24 ± 1hour (1100 rpm) with a magnetic stirrer. Undissolved particles were removed by membrane filtration. The following filtrate, i.e. the saturated solution was used in the test. The solution was checked via laser beam (Tyndall effect), which was negative.

The saturated solution and four dilution levels out of the saturated solution were tested in the definitive test in a geometrical series with a dilution factor of 2: 6.25 - 12.5 - 25.0 - 50.0 - 100 % of the saturated solution. Three replicates were tested for each test item concentration and six replicates for the control.The test media were clear throughout the test period.The environmental conditionswere within the acceptable limits.

The measured concentration of the test item was even < LOD at the start of the exposure (0 hours), therefore no analysis at the end of the exposure was necessary.

All effect values given are based on the nominal test item loadings.

NOEL, LOEL, EL_x-values (0 - 72 hours)

based on the nominal test item loadings

	Growth Rate Inhibition nominal test item loadings [mg/L]
NOEL	5.00
LOEL	> 5.00
ErL10	> 5.00
ErL20	> 5.00
ErL50	> 5.00
	Yield Inhibition nominal test item loadings mg/L]
NOEL	5.00
LOEL	> 5.00
EyL10	> 5.00
EyL20	> 5.00
EyL50	> 5.00

Justification for classification or non-classification

According to the CLP Regulation (EC n. 1272/2008), Part 4: Environmental Hazards, the substances can be classified for hazardous to the aquatic environment (fish toxicity) when the following criteria are met:

A )Acute (short-term) aquatic hazard

Category Acute 1:

96 hr LC 50 (for fish) ≤ 1 mg/l and/or

48 hr EC 50 (for crustacea) ≤ 1 mg/l and/or

72 or 96 hr ErC 50 (for algae or other aquatic plants) ≤ 1 mg/l

B) Long-term aquatic hazard

(iii) Substances for which adequate chronic toxicity data are not available

Category Chronic 1:

96 hr LC 50 (for fish) ≤ 1 mg/l and/or

48 hr EC 50 (for crustacea) ≤ 1 mg/l and/or

72 or 96 hr ErC 50 (for algae or other aquatic plants) ≤ 1 mg/l

and the substance is not rapidly degradable and/or the experimentally determined BCF ≥ 500 (or, if absent, the log K ow ≥ 4).

Category Chronic 2:

96 hr LC 50 (for fish) > 1 to ≤10 mg/l and/or

48 hr EC 50 (for crustacea) > 1 to ≤10 mg/l and/or

72 or 96 hr ErC 50 (for algae or other aquatic plants) > 1 to ≤10 mg/l (Note 2)

and the substance is not rapidly degradable and/or the experimentally determined BCF ≥ 500 (or, if absent, the log K ow ≥ 4).

Category Chronic 3:

96 hr LC 50 (for fish) > 10 to ≤ 100 mg/l and/or

48 hr EC 50 (for crustacea) > 10 to ≤ 100 mg/l and/or

72 or 96 hr ErC 50 (for algae or other aquatic plants) > 10 to ≤ 100 mg/l

and the substance is not rapidly degradable and/or the experimentally determined BCF ≥ 500 (or, if absent, the log K ow ≥ 4).

Category Chronic 4

Cases when data do not allow classification under the above criteria but there are nevertheless some grounds for concern. This includes, for example, poorly soluble substances for which no acute toxicity is recorded at levels up to the water solubility (note 4), and which are not rapidly degradable in accordance with section 4.1.2.9.5 and have an experimentally determined BCF ≥ 500 (or, if absent, a log K ow ≥ 4), indicating a potential to bioaccumulate, which will be classified in this category unless other scientific evidence exists showing classification to be unnecessary. Such evidence includes chronic toxicity NOECs > water solubility or > 1 mg/l, or other evidence of rapid degradation in the environment than the ones provided by any of the methods listed in section 4.1.2.9.5.

Because of the low solubility of the substance in water both Daphnia and Algae tests have been conducted at the limit of solubility (saturated solution = 5 mg/l).

The value of EL50 in the test conducted on Daphnia Magna was greater than 5 mg/l. The same results was obtained in the study conducted with the Pseudokirchneriella subcapitata (ErL50 > 5 mg/l).

In concusion, as no effects have been found at the limit of solubility, the test item is not Classified for Aquatic toxicity.