OO-tert-butyl monoperoxymaleate

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:

2017-05-07 to 2017-11-30; Experimental phase: 07 - 15 June 2017

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)

Version / remarks:

OECD 202 (13 April 2004)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: M-150801 (according to CoA from 14 March 2017)
- Expiration date of the lot/batch: 2018-04-07
- Purity test date: 13.03.2017

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Keep only in the original container. Protect from heat and direct sunlight. Store at max. +30°C
- Stability under test conditions: Not stable

Analytical monitoring:

yes

Details on sampling:

Substance specific analysis was performed at the test site of biochemA GmbH.
- Nominal concentrations: 0.0 (Sample code: NC - negative control); 38.1 (Sample code: A); 61 (Sample code: B); 97.7 (Sample code: C); 156.3 (Sample code: D) and 250.0 mg/L (Sample code: E)
- Sampling method: The samples were filled into 2 mL microcentrifuge tubes and stored in the freezer (s -18 °C). The sampling and documentation is conducted according to the following specification:
* At the start of the test (0 h), the test solutions NC, A, B, C, D and E were sampled before division to the test vessels (each concentration: 4 samples of 1.5 mL).
* After 24 h exposure: Before renewal test solution, all replicates of NC, A, B, C, D and E were sampled (one sample per replicate: 4 samples of 1.5 mL per concentration).
* At the end of the test (48 h): All replicates from NC, A, B, C, D and E were sampled (one sample per replicate: 4 samples of 1.5 mL per concentration).
Of each sampled treatment, one of the samples from 0 h, 24 h (old and fresh) and 48 h is sent to the analytical laboratory at the test site. The remaining samples were stored as retain samples at s -18 °C until finalization of the study.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The stock solutions (one for the start and one for the renewal of the test solutions at 24 h) were prepared by adding 127.4 mg (0 h) and 125.4 mg/L (24 h) test item to 500 mL test medium and stirred for 1 h on a magnetic stirrer at room temperature.
- Controls: Yes

Test organisms (species):

Daphnia magna

Details on test organisms:

The test organism Daphnia magna Straus originates from the clone breeding of the Federal Environment Agency, department IV 2.4, Berlin, and has been cultivated at Hydrotox GmbH since October 2012. The daphnids are cultured at 20 ± 2 °C with 16 h light: 8 h dark and transferred into fresh M4 medium twice a week. They are kept at approx. 10 animals / 200 mL and fed on workdays with Desmodesmus subspicatus algae corresponding to 0.1 mg C × daphnid -1 × day -1. The test organisms used were 3.15 – 22 h old at the start of the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

The temperature during the exposure was 20.6 – 21.3 °C (required 18 – 22 °C, constant within ± 1 °C)

pH:

The pH was 7.7 in the control and 7.4 – 7.7 in the test item treatments

Dissolved oxygen:

The dissolved oxygen concentration was 7.9 – 8.1 mg/L in the control and 7.6 – 8.2 mg/L in the test item treatment

Conductivity:

687 µS/cm

Nominal and measured concentrations:

- Nominal concentrations: 0.0; 38.1; 61.0; 97.7; 156.3 and 250.0 mg/L
- Measured concentrations: 0.0; 33.2; 55.2; 92.9;153.8; 295.9 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beakers
- Material, size, fill volume: 50 mL
- Aeration: Yes: After addition of the stock solutions, except the vitamin stock solution S23, the medium (before renewal / after renewal) was aerated for 2.0 h to achieve oxygen saturation.
- Type of flow-through (e.g. peristaltic or proportional diluter): No: Semi-static system.
- Renewal rate of test solution (frequency/flow rate): Yes, after 24 h
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM
The test was performed with M4 medium according to OECD 202 (2004).

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 16 h light : 8 h dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): Mobility, Mortality

VEHICLE CONTROL PERFORMED: no

RANGE-FINDING STUDY
A preliminary test without GLP was performed before start of this GLP-study. Nominal concentrations of 1, 10, 50 and 100 mg/L test item resulted in 0 % immobility after 48 h exposure.
ln the present study, nominal concentrations of 38.1 — 250 mg/L test item were tested.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

191.16 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

73.06 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

92.95 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

55.24 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: not reported
- Mortality of control: no

See also table 1 " Immobility after 24 h and 48 h exposure" in "Any other information on results" incl. tables" below.

Results with reference substance (positive control):

- Results with reference substance valid?: Yes

Reported statistics and error estimates:

The effect concentrations after 24 h and 48 h exposure were calculated with the statistical software ToxRat Professional 3.2.1.

Table 1: lmmobility after 24 h and 48 h exposure
Nominal test item concentration [mg/L]	Number of daphnids per concentration (4 replicates a 5)	lmmobile daphnids (replicates 1 - 4)								Immobility [%]
		24 h				48 h				24 h	48 h
		1	2	3	4	1	2	3	4
NC	20	0	0	0	0	0	0	0	0	0	0
38.1	20	0	0	0	0	0	0	0	0	0	0
61.0	20	0	0	0	0	0	0	0	0	0	0
97.7	20	0	0	0	0	1	2	2	0	0	25
156.3	20	0	0	0	0	2	1	2	4	0	45
250.0	20	0	0	0	0	2	3	5	3	0	65

The initial measured test item concentrations in the test item treatments were 109 – 148 % (0 h) and 115 – 152 % (24 h new) of the nominal concentrations. Until the renewal of the test solutions and the end of the exposure period, the measured test item concentrations decreased to 67 – 92 % (24 h old) and 68 – 94 % (48 h) of the nominal concentrations.

Validity criteria fulfilled:

yes

Conclusions:

For the conducted semi-static acute immobilization test with Daphnia magna, applying nominal concentrations of 38.1 — 250 mg OO-tert-Butylmonoperoxymaleat/L, the following effect levels were calculated:
- 48 hr EC50 (measured): 191.16 mg/L (95%-CL: 150.00 - 271.07);
- 48 hr EC20 (measured): 101.64 mg/L (95%-CL: 71.83 - 129.06);
- 48 hr EC10 (measured): 73.06 mg/L (95%-CL: 44.38 - 96.27);
- 48 hr LOEC: 92.95 mg/L;
- 48 hr NOEC: 55.24 mg/L.

Immobilisation of the test organisms in the control at the end of the test was 0 % and therefore ≤ 10 %.
Dissolved oxygen concentration in the control and the test item treatments at the end of the test was ≥ 7.6 mg/L and therefore ≥ 3 mg/L.
The test is valid according to OECD Test Guideline 202 (13 April 2004)

Executive summary:

The 48–hr-acute toxicity of the test item to Daphnia magna Straus was studied under semi-static conditions according to OECD 202 (OECD 2003). Daphnids were exposed for 48 h to a control containing no test substance, and OO-tert-butyl monoperoxymaleate at nominal concentrations of 38.1, 61.0, 97.7, 156.3 and 250.0 mg/L and measured concentrations of 33.2; 55.2; 92.9;153.8; 295.90 mg/L (geometric mean).

Mortality/immobilization and sublethal effects were observed daily. 

The 48 – hr EC₅₀ was 191.16 mg/L. 

The 48 – hr NOEC based on immobilization was 55.24 mg/L.

Based on the results of this study, OO-tert-butyl monoperoxymaleate would not be classified as toxic to Daphnia magna Straus in accordance with the CLP classification system. 

This study is classified as acceptable and satisfies the guideline requirements for an acute toxicity study with freshwater invertebrates. 

Results Synopsis

Test Organism Age (e.g. 1^st instar): 3.15 - 22 h

Test Type: Static Renewal

  

- 48 hr EC50 (measured): 191.16 mg/L (95%-CL: 150.00 - 271.07);

- 48 hr EC10 (measured): 73.06 mg/L (95%-CL: 44.38 - 96.27);

- 48 hr LOEC: 92.95 mg/L;

- 48 hr NOEC: 55.24 mg/L.

            

Description of key information

For the conducted semi-static acute immobilization test with Daphnia magna Straus according to OECD 202 (OECD 2004), applying nominal concentrations of 38.1 — 250 mg OO-tert-butyl monoperoxymaleate/L, the following effect levels were calculated:

- 48 hr EC50 (measured): 191.16 mg/L (95%-CL: 150.00 - 271.07);

- 48 hr EC10 (measured): 73.06 mg/L (95%-CI: 44.38 - 96.27);

- 48 hr LOEC: 92.95 mg/L;

- 48 hr NOEC: 55.24 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

191.16 mg/L