2-hydroxyethyl methacrylate

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

Cited as OECD Guide-line 202, part 2 (Daphnia sp., Reproduction Test)

GLP compliance:

yes

Specific details on test material used for the study:

Supplier: Wako Pure Chemical Ind.
Purity: 97.2 %

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

-Test Organisms: 
a) Age at Study Initiation: < 24 hours after hatching 
b) Supplier/Source: Supplied from U.S. EPA Environmental Research  Laboratory

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Post exposure observation period:

Not applicable

Hardness:

55.6 mg/L

Test temperature:

19.8 - 20.4 degree C 

pH:

6.9-7.7

Dissolved oxygen:

7.2-8.9

Salinity:

Not applicable

Nominal and measured concentrations:

6.25, 12.5, 25.0, 50.0 and 100 mg/L- nominal
5.44, 11.7, 24.1, 49.6, and 100 mg/L-measured

Details on test conditions:

-Test Conditions: 
a) Dilution Water Source: Dechlorination water 
b) Dilution Water Chemistry: hardness= 55.6mg/L CaCO3, pH= 7.7, chlorine concentration < 0.02 mg/L 
c) Exposure Vessel Type: 0.8 L-test solution in a 1 L-glass vessel 
d) Nominal Concentrations (as mg/L): 6.25, 12.5, 25.0, 50.0 and 100 
e) Stock solutions preparation and stability: Not used  
f) Number of Replicates: 4 
g) Individuals per Replicate: 10 
h) Test Details: Semi-static 
i) Renewal Rate of Test Water: not describe 
j) Water Temperature Range: 19.8 - 20.4 degree C 
k) Light Condition: 16:8 hours; light darkness cycle 
l) Feeding: Daphids were fed green algae (Chlorella vulgaris); 0.1  - 0.2 mgC/day/individual

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

24.1 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

49.6 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

90.1 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Duration:

21 d

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Details on results:

see tables below: Any other information on results icl. tables

Reported statistics and error estimates:

-Statistical Method: 
a) Data Analysis: Kruskal-Wallis test 
b) Method of Calculating Mean Measured Concentrations (i.e.arithmetic mean, geometric mean, etc.): Time-weighted means

 

	Cumulative number of dead parental Daphnia
Measured conc (mg/l)	Exposure time (day)
	7	14	21
Control	0 (0)	0 (0)	0 (0)
5.44	0 (0)	0 (0)	0 (0)
11.7	0 (0)	0 (0)	1 (2.5)
24.1	0 (0)	0 (0)	0 (0)
49.6	0 (0)	0 (0)	0 (0)
100	0 (0)	0 (0)	0 (0)

Time of the first brood: after 7 days

	Mean number of juveniles produced per adult during exposure to 2-hydroxyethyl methacrylate
Measured conc. (mg/l)	Exposure time (day)
	0-7	8	9	10	11	12	13	14	15	16	17	18	19	20	21
Control	0	3.4	3.4	13.1	13.1	34.4	34.8	57.5	57.5	81.9	81.9	104	104	122	138
5.44	0	4.0	4.0	10.9	10.9	35.1	35.1	57.4	57.4	76.1	76.1	107	107	125	139
11.7	0	1.7	1.7	8.7	8.7	33.2	33.2	40.0	40.0	65.1	65.1	99.0	99.0	107	130
24.1	0	3.1	3.1	9.4	9.4	29.4	29.4	37.4	37.4	58.2	58.2	93.1	93.1	107	127
49.6	0	2.3	2.3	9.0	9.0	25.8	25.8	40.9	40.9	63.2	63.2	85.9	85.9	115	118
100	0	0	0	6.0	6.0	7.4	7.4	19.7	19.7	32.3	32.3	38.8	38.8	59.0	59.6

 

 

	Significance test of difference between mean cumulative numbers of juveniles per adult in control and test vessels after 21 days exposure with 2-hydroxyethyl methacrylate
	0-7	8	9	10	11	12
Measured conc (mg/l)	Vessel No.				Mean	SD	Significant difference
	1	2	3	4
Control	134	142	140	137	138	3.6
5.44	138	138	135	146	139	4.6
11.7	134	133	129	126	130	3.8
24.1	117	125	133	133	127	7.8
49.6	123	106	119	126	118	8.9	**
100	57	62	60	59	60	2.0

** significantly different from control at p < 0.01

Validity criteria fulfilled:

yes

Conclusions:

The 21-day NOEC for reproduction with Daphnia magna was 24.1 mg/L.

Executive summary:

A 21-day chronic toxicity study with 2-hydroxyethyl methacrylate to daphnids (Daphnia magna) was conducted acc. OECD 202 (part 2) under semi-static conditions with 4 replicates of 10 daphnids per test concentration exposed to nominal test concentrations of 0 (control), 6.25, 12.5, 25.0, 50.0, and 100 mg/L. Water samples were measured for analytical verification of test concentrations during the exposure and the resulting time-weighted mean measured concentrations were 0 (control), 5.44, 11.7, 24.1, 49.6, and 100 mg/L. The most sensitive endpoint was reproduction and the resulting 21-day NOEC for reproduction was 24.1 mg/L.

Description of key information

A long-term toxicity test with Daphnia magna exposed to 2-hydroxyethyl methacrylate and conducted under semi-static conditions, and following standard test guidelines (OECD 202, part 2), resulted in a NOEC for reproduction of 24.1 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

NOEC

Remarks:

21 d

Effect concentration:

24.1 mg/L