Tetramethylene dimethacrylate

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-01-31 to 2012-02-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study OECD 201, GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Version / remarks:

adopted 23 March 2006

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

The concentrations of the test item were analytically determined from all test concentrations and the control after 0 hours (test start) and 72 hours (test end). Samples at test start were taken from an additional replicate without algae. At end of the test samples were taken directly from the pooled test replicates.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
stock solution: 100 mg/L, freshly prepared with dilution water.
The stock solution was treated with ultrasound for 15 min and stirred with approximately 1100 rpm for 1 h at room temperature.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: Desmodesmus subspicatus CHODAT SAG 86.81
- Source (laboratory, culture collection): Sammlung von Algenkulturen (SAG), Pflanzenphysiologisches Institut der Universität Göttingen, Nikolausberger Weg 18, 37073 Göttingen, Germany
- Age of inoculum (at test initiation): four day old preculture, prepared in dilution water, was used as inoculum


ACCLIMATION
- Acclimation period: no data
- Culturing media and conditions (same as test or not): according to the guideline (OECD 201 medium)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

21-22°C

pH:

initial: 7.80 to 7.98
final: 7.90 to 8.19

Nominal and measured concentrations:

nominal: 1.00, 2.50, 6.25, 15.6, 39.1 mg/L
measured (geometric mean) 0.828, 2.11, 5.81, 14.9, 38.7 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Sterile Erlenmeyer flasks, capacity: 250 mL, sealed with cotton wool plugs, fill volume 100 mL
- Aeration: agitation, Test containers were placed on a rotary shaker and oscillated at approximately 70 rpm
- Initial cells density: 4910 cells/mL
- Control end cells density: mean 910499 cells/mL
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes, OECD 201 medium

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Photoperiod: 24 hours/day light
- Light intensity and quality: mean 66.3 µE/m²/s (CV 4.62%)

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
Cell density was measured daily via Chlorophyll-a- fluorescence,excitation at 436 nm, emission at 685 nm

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.5
- Range finding study
- Test concentrations: 0.01, 0.10, 1.00, 10.00, 100.00 mg/L
- Results used to determine the conditions for the definitive study:
Growth inhibition 100% at 100.00 mg/L, 45% at 10.00 mg/L, 0% at 1.00 mg/L, 1% at 0.10 mg/L, 0% at 0.01 mg/L
Yield inhibition 100% at 100.00 mg/L, 86% at 10.0 mg/L, 1% at 1.00 mg/L, 4% at 0.10 mg/L, -1% at 0.01 mg/L

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

2.11 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

4.35 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% c.i. 4.07 – 4.64 mg/L

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

9.79 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% CL: 9.45 – 10.1 mg/L

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

2.11 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

3.1 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 95% c.i. 2.61 – 3.71 mg/L

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

4.97 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 95% CL: 4.54 – 5.25 mg/L

Results with reference substance (positive control):

- Results with reference substance valid?
- ErC50: 0.488, 95 % confidence interval: 0.466 – 0.512 / valid range: 0.699 ± 0.471
- EyC50: 0.291, 95 % confidence interval: 0.274 – 0.328 / valid range: 0.318 ± 0.147

Reported statistics and error estimates:

EC10-, EC20- and EC50-values of the growth rate and yield inhibition after 72 hours were calculated by sigmoidal dose-response regression. Calculation of the confidence intervals EC10-, EC20- and EC50-values were carried out using standard procedures.

Mean cell densities [cells/mL] during the final test:

Geometric mean measured test item concentration[mg/L]	Exposure time [h]
	0	24	48	72
38.7	4910	4482	3956	2549
14.9	4910	12648	16298	17750
5.81	4910	18862	74093	319196
2.11	4910	20545	155280	931757
0.828	4910	23711	164036	969172
Control	4910	25319	171447	910499

  

Growth rate, yield during the final test: 

Geometric mean measured test item concentration [mg/L]	Growth rate [/d]	Rate-related inhibition [%]	Yield [cells/mL]	Inhibition of yield [%]
38.7	0	100	0	100
14.9	0.427	75.5	12840	98.6
5.81	1.39	20.2	314286	65.3
2.11	1.75	-0.46	926847	-2.35
0.828	1.76	-1.21	964262	-6.48
control	1.74		905589

Validity criteria fulfilled:

yes

Conclusions:

In this study 1,4-BDDMA was found to inhibit the growth of the freshwater green alga Desmodesmus subspicatus after 72 hours.
The NOEC, EC10 and EC50 values based on growth rate were 2.11 mg/L, 4.35 (95% c.i. 4.07 – 4.64) mg/L and 9.79 (95% c.i. 9.45 – 10.1) mg/L, respectively. 
The NOEC, EC10 and EC50 values based on yield were 2.11 mg/L, 3.10 (95% c.i. 2.61 – 3.71) mg/L and 4.97 (95% c.i. 4.54 – 5.25) mg/L, respectively.
The effect values given are based on the geometric mean measured concentrations of the test item.

Executive summary:

In a 72 hour acute toxicity study, the cultures of Desmodesmus subspicatus CHODAT SAG 86.81 were exposed to 1,4-BDDMA at measured concentrations of 0 (control),0.828, 2.11, 5.81, 14.9 and 38.7 mg/L under static conditions in accordance with the OECD guideline 201 (adopted 23 March 2006). 

The NOEC, EC10 and EC50 values based on growth rate were 2.11 mg/L, 4.35 (95% c.i. 4.07 – 4.64) mg/L and 9.79 (95% c.i. 9.45 – 10.1) mg/L, respectively. 

The NOEC, EC10 and EC50 values based on yield were 2.11 mg/L, 3.10 (95% c.i. 2.61 – 3.71) mg/L and 4.97 (95% c.i. 4.54 – 5.25) mg/L, respectively

 

Microscopic evaluation of the cells at start and end of the incubation period revealed no morphological abnormalities.

 

Results Synopsis

 

Test Organism: Desmodesmus subspicatus CHODAT SAG 86.81

Test Type: Static

 

72 hr ErC50: 9.79 mg/L              95% C.I.: 9.45 – 10.1 mg/L

72 hr EyC50: 4.97 mg/L             95% C.I.: 4.54 – 5.25 mg/L

72 hr ErC10: 4.35 mg/L              95% C.I.:  4.07 – 4.64 mg/L

72 hr EyC10:  3.10 mg/L             95% C.I.:  2.61 – 3.71 mg/L

72 hr NOEC: 2.11 mg/L              

Endpoint(s) Effected:  growth rate, yield

Description of key information

The 72 h EC10 of 1,4-BDMA in freshwater algae was 4.35 mg/L. The 72 h EC50 of 1.4-BDDMA in freshwater algae was 9.79 mg/L (OECD guideline 201, static).

Key value for chemical safety assessment

EC50 for freshwater algae:

9.79 mg/L

EC10 or NOEC for freshwater algae:

4.35 mg/L

Additional information

One study in freshwater algae is available for 1,4-BDDMA, which is considered reliable without restriction (Klimisch score 1).

In a 72 hour acute toxicity study, the cultures of Desmodesmus subspicatus CHODAT SAG 86.81were exposed to 1,4-BDDMA at measured concentrations of 0 (control), 0.828, 2.11, 5.81, 14.9 and 38.7 mg/L under static conditions in accordance with the OECD guideline 201 (adopted 23 March 2006). 

Microscopic evaluation of the cells at start and end of the incubation period revealed no morphological abnormalities.

The NOEC, EC10 and EC50 values based on growth rate were 2.11 mg/L, 4.35 mg/L and 9.79 mg/L, respectively.