3,6,9-trioxaundecamethylene dimethacrylate

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:

2017-07-10 to 2017-11-16

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)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Periodic analyses of the water for potential contaminants were not performed according to GLP Standards, but were performed using a certified laboratory and standard US EPA analytical methods.

Analytical monitoring:

yes

Details on sampling:

Analytical Sampling
Test water samples were collected from the batches of test solution prepared for each treatment and control group at the beginning of the test, and from two of the four replicate test chambers in each treatment and control group at 48 hours (± 1 hour) to measure concentrations of the test substance. Samples (20.0 mL) were collected from mid-depth and placed in glass vials. Concentrated phosphoric acid (20.0 µL) was added to each vial, and the samples were processed immediately for analysis.

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

Test Organism
The cladoceran, Daphnia magna, was selected as the test species for this study. This species is representative of an important group of aquatic invertebrates and was selected for use in the test based upon past history of use in the laboratory. Daphnids used in the test were <24-hour old neonates obtained from cultures maintained by EAG Laboratories in Easton, Maryland. Identification of the species was verified by the supplier of the original stock culture.

Adult daphnids were cultured in water from the same source and at approximately the same temperature as used during the test. During the 2-week period immediately preceding the test, water temperatures in the cultures ranged from 20.0 to 20.8ºC, the pH of the water ranged from 7.8 to 8.4, and the dissolved oxygen concentrations were ¿ 7.5 mg/L (¿ 83% of saturation). The three adult daphnids used to supply neonates for the test were held for 14 days prior to collection of the juveniles for testing, and had each produced at least two previous broods. Adult daphnids in the culture had produced an average of at least three young per adult per day over the 7-day period prior to the test. The adults showed no signs of disease or stress, no ephippia were produced during the holding period, and mortality in the culture stock was 0% in the two-day period prior to test initiation.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

140 mg/L as CaCO3 at test initiation

Test temperature:

19.8 - 20.5 °C

pH:

8.3 - 8.5

Dissolved oxygen:

>= 85%; no aeration

Nominal and measured concentrations:

Nominal: 0 (Control), 38, 75, 150, 300, 600 mg/L
Measured: < LOQ (Control), 37, 73, 144, 288, 580 mg/L

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

391 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

RESULTS AND DISCUSSION

Measurement of Test Concentrations

Nominal concentrations selected for use in this study were 38, 75, 150, 300 and 600 mg a.i./L. Test solutions in the test chambers at these nominal concentrations appeared clear and colorless during the test, with no evidence of precipitation observed.

Results of analyses to measure concentrations of tetraethylene glycol dimethacrylate in the test solution samples collected during the test are presented in Table 1. Measured concentrations of the samples ranged from approximately 93 to 101% of nominal. When measured concentrations of the samples were averaged, the mean measured test concentrations for this study were 37, 73, 144, 288 and

580 mg a.i./L, representing 97, 97, 96, 96 and 97% of nominal concentrations, respectively. The results of the study were based on the mean measured concentrations.

Table 1 Measured Concentrations of Tetraethylene Glycol Dimethacrylate in Freshwater

Nominal Test Concentration (mg a.i./L)		Sample Number (524A-133)	Sampling Time (Days)	Measured Concentration (mg a.i./L)^1,2	Percent of Nominal^2	Mean Measured Concentration (mg a.i./L)^3	Mean Measured Percent of Nominal^3
Negative		1	0	< LOQ	--	--	--
Control		7	2	< LOQ	--
		8	2	< LOQ
38		2	0	37.7	99.2	37 ± 1.41	97
		9	2	35.8	94.1	CV = 3.85%
		10	2	35.6	93.6
75		3	0	75.7	101	73 ± 3.68	97
		11	2	71.0	94.7	CV = 5.03%
		12	2	70.0	93.3
150		4	0	149	99.2	144 ± 6.72	96
		13	2	139	92.9	CV = 4.66%
		14	2	140	93.3
300		5	0	296	98.8	288 ± 10.96	96
		15	2	279	92.9	CV = 3.80%
		16	2	282	94.1
600		6	0	598	99.6	580 ± 21.16	97
		17	2	565	94.2	CV = 4.51%
		18	2	557	92.9
	^1   The limit of quantitation (LOQ) wasset at 20.0 mg a.i./L,defined as the lowest nominal concentration in a fortified sample with acceptable recovery between 70 – 110%. ^2   Results were generated using Agilent OpenLab CDS Rev. A.01.05. Manual calculations may differ slightly. ^3   Mean Measured Concentration calculated as ([Day 0] + [average of Day2])/2 using Excel 2010 in full precision mode. Manual calculations may differ slightly.

Observations and Measurements

Measurements of temperature, pH and dissolved oxygen of the water in the test chambers are presented in Table 2. Water temperatures were within the 20 ± 1¿C range established for the test. Measurements of pH ranged from 8.3 to 8.5. Dissolved oxygen concentrations remained = 7.7 mg/L (= 85% of saturation) throughout the test. The measurements of hardness, alkalinity, specific conductance and TOC in the dilution water at the beginning of the test were typical of EAG Laboratories-Easton well water (Table 3). Light intensity at the beginning of the test was 658 lux at the surface of the water of one representative test chamber.

Table 2 Temperature, Dissolved Oxygen and pH of Water in the Test Chambers

 

Mean Measured Concentration (mg a.i./L)	Replicate	0 Hour				24 Hours				48 Hours
		Temp.^1 (°C)	DO^2 (mg/L)	pH		Temp.^1 (°C)	DO^2 (mg/L)	pH		Temp.^1 (°C)	DO^2 (mg/L)	pH
Negative	A	19.9	8.8	8.5		20.2	8.7	8.4		20.4	8.6	8.4
Control	B	19.9	8.8	8.5		20.3	8.7	8.5		20.4	8.6	8.5
	C	19.8	8.8	8.5		20.3	8.8	8.5		20.4	8.6	8.5
	D	19.8	8.8	8.5		20.3	8.6	8.5		20.4	8.6	8.5
37	A	19.9	8.9	8.5		20.2	8.7	8.5		20.4	8.4	8.5
	B	19.9	8.8	8.5		20.3	8.7	8.5		20.4	8.5	8.5
	C	19.8	8.8	8.5		20.3	8.7	8.5		20.5	8.3	8.5
	D	19.8	8.7	8.5		20.3	8.7	8.5		20.4	8.3	8.5
73	A	19.9	8.7	8.5		20.2	8.7	8.5		20.4	8.4	8.5
	B	20.0	8.7	8.5		20.2	8.6	8.5		20.4	8.4	8.5
	C	19.9	8.7	8.5		20.3	8.7	8.5		20.5	8.3	8.5
	D	19.9	8.7	8.5		20.3	8.7	8.5		20.4	8.3	8.5
144	A	20.2	8.6	8.5		20.3	8.7	8.5		20.4	8.3	8.5
	B	20.2	8.6	8.5		20.3	8.6	8.5		20.5	8.4	8.5
	C	20.1	8.5	8.5		20.3	8.7	8.5		20.4	8.3	8.5
	D	20.1	8.5	8.5		20.3	8.7	8.5		20.4	8.3	8.5
288	A	20.2	8.3	8.5		20.3	8.6	8.4		20.5	8.1	8.5
	B	20.2	8.3	8.5		20.3	8.5	8.4		20.4	8.1	8.4
	C	20.2	8.3	8.5		20.3	8.5	8.4		20.5	8.1	8.4
	D	20.2	8.3	8.5		20.4	8.5	8.4		20.5	8.0	8.4
580	A	20.4	8.3	8.4		20.4	8.5	8.4		20.4	7.9	8.3
	B	20.4	8.3	8.4		20.4	8.3	8.4		20.4	7.9	8.3
	C	20.4	8.2	8.4		20.4	8.4	8.4		20.5	7.8	8.3
	D	20.4	8.2	8.4		20.4	8.3	8.4		20.5	7.7	8.3
^1  Manual temperature measurements. Temperature monitored continuously during the test ranged from 19.62 to 20.13°C, measured to the nearest 0.01°C. ^2  A dissolved oxygen concentration of 5.4 mg/L represents 60% saturation at 20°C in freshwater.

Table 3 Specific Conductance, Hardness, Alkalinity and Total Organic Carbon (TOC) in the Dilution Water at Test Initiation

 

Parameter	Day 0
Specific Conductance	339
(µS/cm)
Hardness	140
(mg/L as CaCO3)
Alkalinity	168
(mg/L as CaCO3)
Total Organic Carbon (TOC)	<1
(mg C/L)

Daily observations of immobility and other signs of toxicity observed during the test are presented in Table 4. All daphnids in the negative control appeared normal throughout the test. All daphnids in the 37, 73 and 144 mg a.i./L treatment groups also appeared normal throughout the test, with no immobile daphnids or overt signs of toxicity observed. Percent immobility in the 288 and 580 mg a.i./L treatment groups at test termination was 10 and 95%, respectively. Signs of toxicity observed among the surviving daphnids in the 288 and 580 mg a.i./L treatment groups at test termination included lethargy. Therefore in this study, the no-immobility concentration and the NOEC were both 144 mg a.i./L. EC50 values at 24 and 48 hours were determined from the immobility data and are shown in Table 5.

 

Table 4 Cumulative Immobility and Observations 

Mean Measured Concentration (mg a.i./L)	Rep.	No. Exposed	~ 3.5 Hours			24 Hours			48 Hours		Cumulative Percent Immobile
			Number Immobile^1	Observations^2		Number Immobile^1	Observations^2		Number Immobile^1	Observations^2
Negative	A	5	0	5 AN		0	5 AN		0	5 AN	0
Control	B	5	0	3 Q,AN; 2 AN		0	5 AN		0	5 AN
	C	5	0	5 AN		0	5 AN		0	5 AN
	D	5	0	5 AN		0	5 AN		0	5 AN
37	A	5	0	5 AN		0	5 AN		0	5 AN	0
	B	5	0	5 AN		0	5 AN		0	5 AN
	C	5	0	5 AN		0	5 AN		0	5 AN
	D	5	0	5 AN		0	5 AN		0	5 AN
73	A	5	0	5 AN		0	5 AN		0	5 AN	0
	B	5	0	5 AN		0	5 AN		0	5 AN
	C	5	0	5 AN		0	5 AN		0	5 AN
	D	5	0	5 AN		0	5 AN		0	5 AN
144	A	5	0	5 AN		0	5 AN		0	5 AN	0
	B	5	0	5 AN		0	5 AN		0	5 AN
	C	5	0	5 AN		0	5 AN		0	5 AN
	D	5	0	5 AN		0	5 AN		0	5 AN
^1   Cumulative number of immobile daphnids. Any immobile daphnids were removed from the test chambers at each observation interval. ^2   Observations of surviving organisms: AN = appear normal; Q,AN = trapped at water surface but appear normal after gentle submersion.

Table 4 (Continued) Cumulative Immobility and Observations

 

Mean Measured Concentration (mg a.i./L)	Rep.	No. Exposed	~ 3.5 Hours			24 Hours			48 Hours		Cumulative Percent Immobile
			Number Immobile^1	Observations^2		Number Immobile^1	Observations^2		Number Immobile^1	Observations^2
288	A	5	0	5 AN		0	5 AN		0	5 AN	10
	B	5	0	5 AN		0	5 AN		0	5 AN
	C	5	0	5 AN		0	1 C; 4 AN		2	3 AN
	D	5	0	5 AN		0	5 AN		0	5 AN
580	A	5	0	1 C; 4 AN		3	2 C		4	1 C	95
	B	5	0	5 AN		3	2 C		5	--
	C	5	0	5 AN		3	2 C		5	--
	D	5	0	5 AN		4	1 C		5	--
^1  Cumulative number of immobile daphnids. Any immobile daphnids were removed from the test chambers at each observation interval. ^2  Observations of surviving organisms: AN = appear normal; C = lethargy.

Table 5 EC₅₀ValuesBased on Mean Measured Test Concentrations

 

Time	EC50 (mg a.i./L)	95% Confidence Interval (mg a.i./L)	Statistical Method
24 Hours	> 580	--^1	NA^2
48 Hours	391	338 – 459	Probit Analysis
^1 95% confidence limits could not be calculated with the immobility data obtained. ^2 NA = not applicable; <50% immobility precluded statistical calculation of an EC50value.

Conditions for the Validity of the Test

The following criteria were used to judge the validity of the test and were met in this study:

1. Immobility of the daphnids in the negative control group will not exceed 10% by the end of the test. In this study, immobility in the negative control group was 0%.

2. The dissolved oxygen concentration will be at least 60% of the air-saturation value throughout the test. In this study, the dissolved oxygen concentration remained = 85% of saturation.

 

Validity criteria fulfilled:

yes

Conclusions:

CONCLUSIONS
The cladoceran, Daphnia magna, was exposed for 48 hours under static conditions to five mean measured concentrations of tetraethylene glycol dimethacrylate ranging from 37 to 580 mg a.i./L. Based on the mean measured concentrations, the 48-hour EC50 value was 391 mg a.i./L, with a 95% confidence interval of 338 to 459 mg a.i./L. The slope of the concentration-response curve was 9.627. The no-immobility concentration and the NOEC both were 144 mg a.i./L.

Executive summary:

The cladoceran, Daphnia magna, was exposed for 48 hours under static conditions to five mean measured concentrations of tetraethylene glycol dimethacrylate ranging from 37 to 580 mg a.i./L. Based on the mean measured concentrations, the 48 -hour EC50 value was 391 mg a.i./L, with a 95% confidence interval of 338 to 459 mg a.i./L. The slope of the concentration-response curve was 9.627. The no-immobility concentration and the NOEC both were 144 mg a.i./L.

Description of key information

A study assessing the acute toxicity of the test item to Daphnia magna was conducted in accordance with the OECD 202 and OPPTS 850.1010 Test Guidelines and GLP requirements.

The 48h-EC50 was determined to be 391 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

391 mg/L