Bis(pentane-2,4-dionato-O,O')magnesium

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

Regulatory Requirements:
In deviation to the Study Plan, also the Toxic Substances Control Act (TSCA, 1975) was included in the Regulatory Requirements. This deviation did not have any impact on test results.

Experimental conditions
Minimum temperature in the negative control tank (min temperature 12.9°C) and in test item solutions tanks at 4.3 mg/L (min temperature 12.9°C), 9.4 mg/L (min temperature 12.0°C), 20.7 mg/L (min temperature 12.1°C) and 45.5 mg/L (min temperature 13.1°C) was lower than the OECD recommended range corrected for probe precision (13.5 – 16.5°C); this deviation was considered acceptable and without influence on test results, since neither sublethal effects nor lethal effects were observed during the test period.
Maximum temperature (16.9°C) in test item solution tank at 100.0 mg/L was higher than the OECD recommended range corrected for probe precision (13.5 – 16.5°C); this deviation was considered acceptable and without influence on test results, since it occurred only for a very short period of time (the first 5 minutes of the exposure period) and the gap to accepted temperature was very narrow (0.4°C).

Test item
EEC number is 628-792-9, as declared by the Sponsor. This deviation did not have any impact on test results.

Deviations:

yes

Remarks:

See in version/remarks above.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Bis(pentane-2,4-dionato-O,O')magnesium

EC Number:

237-857-7

EC Name:

Bis(pentane-2,4-dionato-O,O')magnesium

Cas Number:

14024-56-7

Molecular formula:

C10H14MgO4

IUPAC Name:

magnesium;4-oxopent-2-en-2-olate

Test material form:

solid: particulate/powder

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Samples of each test solution were taken, immediately after preparation at time 0, at 48 hours renewal and at the end of test (96 hours). Negative control samples were analysed at the same time to verify the absence of test item contamination.
Samples were labelled and analysed immediately after sampling.
Duplicate samples of the test water and the negative control were taken from the test solutions; one sample was analysed, while the respective duplicates were stored as retain samples to be analysed only if necessary.

Test solutions

Vehicle:

no

Details on test solutions:

The test concentrations were chosen in accordance with the results of a no GLP pre-test (range-finding test), whose relevant Raw Data were archived under the code of the present study.
The test was performed at five test item concentrations in a geometric series (differing by a constant equal to 2.2), namely 4.3, 9.4, 20.7, 45.5 and 100.0 mg/L of test item.
The test medium was prepared as follows:
at the test start, 25 litres of a 100.0 mg test item/L stock solution were prepared by direct weighing into reconstituted water both at time 0 and at 48 hours renewal;
The obtained solutions were manually vigorously mixed until complete solubilization of the test item; thereafter the 5 flasks were merged together in the test tank and the other test concentrations were prepared by dilution with reconstituted water as described below
The obtained solutions were transparent and clear.
A negative control with reconstituted water only was also tested.


test solutions preparation:
Test solution 1:
-nominal test item solution concentration : 4.3mg/L
-final volume of tank : 15000mL
-added volume of test item stock solution 100.0 mg/L: 640mL

Test solution 2:
-nominal test item solution concentration : 9.4mg/L
-final volume of tank: 15000mL
-added volume of test item stock solution 100.0 mg/L: 1410mL

Test solution 3:
-nominal test item solution concentration : 20.7mg/L
-final volume of tank: 15000mL
-added volume of test item stock solution 100.0 mg/L: 3100mL

Test solution 4:
-nominal test item solution concentration : 45.5mg/L
-final volume of tank : 15000mL
-added volume of test item stock solution 100.0 mg/L: 6820mL

This procedure was repeated for the renewal of test solutions at 48 hours.
The test solutions and negative control were let reach the correct temperature and pH and dissolved oxygen concentration were measured before adding the fish.

Test organisms

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

The study was performed with rainbow trout (Oncorhynchus mykiss) obtained from the Research Foundation “Edmund Mach” (S. Michele all’Adige - Italy). Juvenile fish were used and all of them were approximately the same age and size. Prior to the start of the test, the body weight and length of a representative number of fish (at least ten) was determined, recorded and reported in the Raw Data and in the Final Report. The mean body length was 4.7 cm.

In accordance with the test guidelines, the fish were held in the Test Facility laboratories for at least 12 days (13 days) in the same conditions, as for water quality, temperature and illumination, of the test. During the holding period, the fish were daily fed with specific fish food. Feeding was stopped at least 24 hours before the test start.

Study design

Test type:

semi-static

Water media type:

other: saltwater and freshwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Hardness:

10 - 250 mg/L as CaCO3

Test temperature:

The temperature range provided by OECD No. 203 (1992) is 15.0 ± 2.0 °C, this range was corrected according to the probe precision, therefore the range to be considered for the test was 13.5 – 16.5 °C. Each temperature value was corrected according to the correction factor.

pH:

pH values were measured with a portable pHmeter and they did not vary more than 1.34 units throughout the test period.

Dissolved oxygen:

The dissolved oxygen concentrations were measured with a portable oxymeter and they were always above 60 % of the air saturation value, according to OECD No 203 (1992).

Conductivity:

< 10 μS/cm)

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

ca. 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 2

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 3

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 4

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

ca. 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Executive summary:

The Short-term toxicity to fish test was performed according to the OECD Guideline 203 (Fish, Acute Toxicity Test).

96h EC0, EC50, EC100 and NOEC were respectively:

100mg/L, >100mg/L, >100mg/L and 100mg/L in Oncorhynchus mykiss.