7,7,9(or 7,9,9)-trimethyl-4,13-dioxo-3,14-dioxa-5,12-diazahexadecane-1,16-diyl bismethacrylate

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:

06 - 27 Jul 2009

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

Temperature much higher than recommended by the guideline.

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes (incl. QA statement)

Remarks:

Landesamt für Umwelt, Wasserwirtschaft und Gewerbeaufsicht, Mainz, Germany

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 and 100 mg/L

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: the solubility of the test item lies below 100 mg/L, thus in a second test the water accommodated fraction was prepared for the test. The nominal load was weighed, adding the corresponding amount of dilution water and shaking vigorously for 24 h. The solution was then filtered through 0.45 µm filter.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain: Berlin
- Source: Umweltbundesamt, Berlin, Germany
- Age at study initiation (mean and range, SD): between 0 - 24 h
- Method of breeding: Daphnids were bred in the laboratory (similar to the method EN ISO 6341 following SOP 11500201) throughout the year for the use in toxicity tests. They multiply by parthenogenesis.
- Feeding during breeding: unicellular green algae (Desmodesmus subspicatus)
- Medium: M4-Medium (recipe of ELENDT)
- Temperature during breeding: 20 ± 2 °C
- Photoperiod: 16/8 h using neon tubes

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test temperature:

26.2 - 26.8 °C (test item)
24.4 - 25 (positive control)

pH:

7.6 - 7.8 (test item)
7.5 - 7.7 (positive control)

Dissolved oxygen:

7.6 - 7.7 mg/L (test item)
7.9 - 8.6 mg/L (positive control)

Nominal and measured concentrations:

100 mg/L (nominal)
1.2 mg/L (mean measured)

Details on test conditions:

TEST SYSTEM
- Fill volume: 20 mg/L
- Aeration: yes
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to guideline
- Culture medium different from test medium: yes
- Intervals of water quality measurement: the content of the test item, pH and concentration of dissolved oxygen were measured at the beginning and at the end of the test

OTHER TEST CONDITIONS
- Adjustment of pH: yes, to 7.8 ± 0.2

EFFECT PARAMETERS MEASURED: after 24 and 48 h the immobilised Daphnids were counted

TEST CONCENTRATIONS
- Range finding study: yes, without analytics, not further data in the report

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 1.2 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: corresponding to 100 mg/L nominal concentration

Details on results:

- Mortality of control: no
- Other biological observations: the concentration tested showed no toxicity to Daphnids

Results with reference substance (positive control):

- EC50 (24 h): 0.7 mg/L (95% CI: 0.6 - 1.7 mg/L)
- EC100 (24 h): 2 mg/L
- NOEC (24 h): 0.5 mg/L

Table 1: Effect concentrations.

Parameter	Value
	24 h	48 h
EC50	> 1.2 mg/L	> 1.2 mg/L
EC100	> 1.2 mg/L	> 1.2 mg/L
NOEC	≥1.2 mg/L	≥1.2 mg/L

* 95% CI was not determinable

Table 2: Measured concentrations.

Nominal concentr. in mg/L	Measured concentr. in mg/L		% recovery after 48 h	% of nominal concentr.		Mean meas. concentr. in mg/L
	0 h	48 h		0 h	48 h
0	< LOQ	< LOQ	-	-	-	-
100	1.2	1.1	90	1	1	1.2

LOQ = 0.08 mg/L

Because of unexpected low measured concentrations an additional experiment was performed and the results are shown in table 3.

Table 3: Measured concentrations of the test item when prepared as WAF in both deionised and dilution water filtered and unfiltered.

Nominal concentr. in mg/L	Measured concentr. in mg/L in deionised water		Measured concentr. in mg/L in dilution water
	filtered	unfiltered	filtered	unfiltered
100	4.9	5.1	2	1.8

Validity criteria fulfilled:

yes

Description of key information

EC50 (48 h) > 1.2 mg/L (mean measured, corresponding to 100 mg/L nominal) for Daphnia magna (OECD 202)

Additional information

One study is available investigating the short term toxicity of the substance (CAS 72869-86-4) to aquatic invertebrates. The study was conducted according to OECD 202 and GLP. A nominal load of 100 mg test item/L was weighed into the test vessel, adding the corresponding amount of dilution water and shaking vigorously for 24 h. The solution was then filtered through a 0.45 µm filter. The test organism Daphnia magna was then exposed in a static system for 48 h to the single nominal concentration (limit test). An analytical monitoring was performed via HPLC-UV-VIS and 1.2 mg test item/L (mean) was measured. The EC50 (48 h) was determined to be 1.2 > mg/L (mean measured).