Reaction mass of decyl acrylate and octyl acrylate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-03-08 to

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

Test temperatures during the test were outside the range 21-25°C controlled at ± 2°C. This deviation was not considered to have affected the outcome or the achievement of the study objectives.

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Aliquots were removed from each prepared concentration every day from fresh and old solutions.

Vehicle:

no

Details on test solutions:

Due to the test item characteristics, test solutions were prepared from saturated stock solutions prepared using slow-stirring conditions described in the OECD 123 guideline. This method used a special temperature-controlled glass-jacketed test vessel with a sampling tap at the lower end and a magnetic stir bar at its bottom. A known volume of test medium was first poured into the test flask. Then a known quantity of test item was gently added at the surface of water. The solution was continuously stirred during at least 24h with the magnetic stir bar at a speed avoiding formation of an emulsion (i.e. 250 rpm). The speed was set up in order to create a vortex depth of around 0.5 cm.

As the test was conducted with semi-static conditions a new test item stock solution was prepared as described below:

Saturated test solution 1: 6L test medium, 68.2 µL test item, 10 mg/L corresponding loading rate, 72h stirring duration
Saturated test solutions 2, 3 and 4: 7L test medium, 79.6 µL test item, 10 mg/L corresponding loading rate, 24h stirring duration

The pH of the test solutions were not adjusted.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

The fish used (Danio rerio (Teleostei, Cyprinidae)) was obtained from “La Grande Rivière France” (69490 Saint-Forgeux, FRANCE). All fish were in good health and free from any apparent malformation. Mortality of the batch was less than 5% in the week preceding the start of the study. No disease treatments were administered throughout holding and testing.

Holding was maintained within the laboratory at a temperature of 21-25°C in glass tanks. A light cycle of 12 h light and 12 h dark was applied, illumination being provided by fluorescent tubes (intensity between 400 and 800 lux at the surface of the tanks). Tanks were aerated to ensure that the dissolved oxygen concentration is at least 60% of air saturation value in holding tanks and in test tanks. During holding, fish were fed twice per day with ground flake food TetraMin®.

The fish were not fed for a period of 24h prior to test commencement and up to the end of the test.

Fish were added to the test tanks within 30 min after the completion of test solution preparation. All test fish were weighed prior to the test and a representative number of test fish batch (10 at random) was measured after the test to assess compliance with guideline criteria.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

Temperature was not maintained in a range from 21°C to 25°C and did not remain constant within ± 2°C during the test:
- mean measured temperature: 21.5°C
- min.: 19.4°C
- max.: 25.6°C.

pH:

0h (fresh solution): 7.8 - 7.9
24h (old solution): 7.6 - 7.8
24h (fresh solution): 8.0
48h (old solution): 7.6 - 7.7
48h (fresh solution): 8.0
72h (old solution): 7.7
72h (fresh solution): 7.9 - 8.0
96h (old solution): 7.6 - 7.7

Dissolved oxygen:

Dissolved oxygen (% of air saturation):
0h (fresh solution): 90.3 - 95.0
24h (old solution): 83.2 - 90.2
24h (fresh solution): 96.8 - 98.9
48h (old solution): 84.3 - 89.1
48h (fresh solution): 97.5 - 99.2
72h (old solution): 84.9 - 87.9
72h (fresh solution): 98.5 - 101.6
96h (old solution): 83.7 - 90.2

Nominal and measured concentrations:

Nominal concentrations (% saturated stock solution):
0 (Control), 5.0, 9.5, 17.0, 30.5, 55.5, 100.0

Measured concentrations (geometric means, mg/L):
0 (Control), 0.04, 0.05, 0.07, 0.10, 0.17, 0.41

Details on test conditions:

Test tanks (filled with 2.5 L of test solution) containing fish were incubated with a photo period of 12 hours of darkness per 24 h.

All test tanks were made of clear glass and covered by plates with ventilation holes to minimise evaporation and avoid the entry of dust into the solutions.

Test solutions were prepared using the synthetic medium. Chemical reagents used for the preparation of the dilution water were “analytical grade”.

The control treatment was maintained under the same conditions, with no test item.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 0.41 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

not determinable

Remarks:

No effects up to the test item saturation limit in water.

Details on results:

No mortality observed at the end of the trial except for the highest tested concentration (100.0% saturated stock solution, 14.3% mortality).

Results with reference substance (positive control):

The sensitivity of the test system and the methodology are evaluated with every batch of fish by performing an acute toxicity test on potassium dichromate. The values of 24h-LC50 obtained with the batch used for the definitive test were as follows:

Batch 17/Br/01/1: 24h-LC50 = 205.8 mg/L.

This result is consistent with the laboratory control quality chart.

Sublethal observations / clinical signs:

The appearance of the test solutions was visually checked at the beginning and at the end of the test. Solutions were found to be clear. No precipitation was observed at the end of the test.

Validity criteria fulfilled:

yes

Conclusions:

The acute toxicity of the test item to Danio rerio exposed for 96h was assessed according to the OECD 203 Guideline. Fish were exposed to a series of dilutions of saturated stock solutions in dilution water (renewed every day) throughout the test period.

Test item concentrations were determined at each observation time in fresh and old solutions. Results showed a considerable loss of the test item (deviation >20%); consequently, the exposure concentrations were based on the geometric mean of measured concentration. As no significant mortality was observed, no EC10 or EC50 values were calculated. The test item has no effect on zebra fish up to its saturation limit in water.

Executive summary:

This study was designed to determine the effects of the test item to Danio rerio over a 96h period with semi-static conditions, according to the OECD 203 Guideline.

 

Due to the test item characteristics test solutions were prepared from saturated stock solutions prepared using slow-stirring conditions described in the OECD 123 guideline (a new test item stock solution was prepared every day).

 

Test item concentrations were determined at each observation time. Results have shown an important loss of the test item; as a consequence the exposure concentrations were based on the geometric mean of measured concentration. As no significant mortality was observed no EC10 or EC50 values were calculated, the test item has no effect on zebra fish up to its saturation limit in water.

 

The definitive test met the validity criteria of the test guideline detailed as follows:

• The mortality in the control did not exceed 10% at the end of the test (0%),
• The dissolved oxygen in the test tanks remained above 60% of the air saturation value throughout the test (>83.2% of ASV),
• The pH did not vary by more than 1 unit.

Description of key information

A test was performed according to the OECD Test Guideline 203 to assess acute toxicity effects of Reaction mass of decyl acrylate and octyl acrylate (EC number 911-295-9) on Danio rerio. The 96h-LD50 was not determined due to the maximum observed effect being 14.3% mortality at the highest tested concentration (geometric mean of measured concentrations: 0.41 mg/L). It is therefore considered that the LD50 is greater than 0.41 mg/L.

 

As a conservative approach, the LD50 value used for chemical safety assessment is considered to be equal to 0.41 mg/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.41 mg/L