Magnesium fluoride

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:

30 January 2017 – 03 February 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

None deviations from the guideline was recorded.

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: Materion / lot 662599-1
- Expiration date of the lot/batch: 31-Jul 2017
- Purity test date: 18- Jan-2016

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: RT, away from moisture
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle: low solubility
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: not expected

Analytical monitoring:

yes

Remarks:

ICP-OES-Method to determine Magnesium in the test item was validated.

Details on sampling:

Samples were WAFs. This was done by weighing the nominal load 100 mg/L (real load 100.09 mg/L), adding the corresponding amount of tap water and stirring for 23.5 hours. The resulting solution was filtrated through 0.45 µm Cellulose ester filters. Sampling intervals were 0, 24, 48, 72 and 96 hours.

Vehicle:

no

Details on test solutions:

The water-accommodated fraction (WAF) was prepared for the test a day before starting the test. It was done by weighing the nominal load 100 mg/L (real load 100.09 mg/L), adding tap water and stirring for 23.5 hours. The resulting solution was filtrated through 0.45 µm Cellulose ester filters.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Danio rerio HAMILTON-BUCHANAN
- Source: Dehner Garten Center, 67433 Neustadt
- Age at study initiation (mean and range, SD): sexually immature young fish
- Length at study initiation: length 2 +- 1 cm
-Vessels: polyethylene aquaria

ACCLIMATION
- Acclimation period: 12 days
- Acclimation conditions: same as test
- Type and amount of food during acclimation: warmwater fishfood about 1-2% of body weight per day
- Feeding frequency during acclimation: three times a day
- Health during acclimation: mortality did not surpass 5 %

FEEDING DURING TEST
The test fish were no longer fed 24 hours before the start of the test.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

0.83 mmol/L

Test temperature:

22.0 – 22.6 °C, were measured at 0h, 24h, 48h, 72h and 96h in the control and loaded conc.

pH:

7.9-8

Dissolved oxygen:

9.6-7.7 O2 in mg/L, were measured at 0h, 24h, 48h, 72h and 96h in the control and loaded conc.

Conductivity:

228 µS/cm

Nominal and measured concentrations:

blank control and nominal concenration of 100 mg/L (real load 100.09 mg/L)

Details on test conditions:

TEST SYSTEM
- Test vessel: glass aquaria, maximal volume 10 L
- Material, size, headspace, fill volume: 10 L
- Aeration: accomplished with glass tubes
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution: none
- No. of organisms per vessel: loading of 1 fish/L, 7 fishes per vessel
- No. of vessels per concentration (replicates): 1 vessel per concentration, each containing 7 L test solution and 7 fish
- No. of vessels per control (replicates): 1 vessel, each containing 7 L test solution and 7 fish
- No. of vessels per vehicle control (replicates): 1 vessel, each containing 7 L test solution and 7 fish


TEST MEDIUM / WATER PARAMETERS (see details in section "Any other information in results incl. tables", table 4)
- Source/preparation of dilution water: Good quality drinking water was used, chlorine-free tap water
- Total organic carbon: < 0.50 mg/L
- Metals: Na, K, Ca, Mg, Al, Fe, Mn, Nh4, NO3, NO2, Sb, As, Pb, Cd, Cr, Cu, Ni, Hg, Se, B, F, were measured.
- Pesticides: < LOD µg/L
- Chlorine: 10 mg/L
- Ca/mg ratio: 32 mg/L
- Intervals of water quality measurement: : Mar. 2016, Wasserwerk Kirrweiler

OTHER TEST CONDITIONS
- Adjustment of pH: none
- Photoperiod: 12/12 hours, using neon tubes


TEST CONCENTRATIONS
- Justification for using less concentrations than requested by guideline: In the non-GLP pre-test no toxicity on the test organisms (Danio) was observed using the 100 mg/L test item in medium. Therefore, a limit test with 100 mg/L will be performed only
- Test concentrations: blank control and 100 mg/L

Reference substance (positive control):

not specified

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (total fraction)

Basis for effect:

mortality (fish)

Details on results:

- Mortality of loaded concentrations: No mortality was observed.
- Behavioural abnormalities: No abnormal behaviour of the surviving fish was observed - Other biological observations:
- Mortality of control: No mortality was observed.
- Abnormal responses: No abnormal behaviour of the surviving fish was observed

See section "Any other information on results incl. tables" for details on results (table 5, table 6, table 7, table 8 and table 9)

Sublethal observations / clinical signs:

Table 4. Date of analysis: Mar. 2016, Wasserwerk Kirrweiler
Parameter	Value	Unit
sodium	4.7	mg/L
potassium	2.6	mg/L
calcium	32	mg/L
magnesium	3.6	mg/L
aluminium	0.011	mg/L
iron	<0.005	mg/L
manganese	<0.005	mg/L
ammonium	<0.05	mg/L
nitrate	5.5	mg/L
nitrite	<0.005	mg/L
chloride	10	mg/L
sulphate	11	mg/L
total organic carbon (TOC)	< 0.50	mg/L
antimony	<0.001	mg/L
arsenic	<0.001	mg/L
lead	<0.001	mg/L
cadmium	<0.0001	mg/L
chromium	<0.001	mg/L
copper	<0.001	mg/L
nickel	<0.001	mg/L
mercury	<0.0001	mg/L
selenium	<0.001	mg/L
bor	<0.01	mg/L
cyanide	<0.005	mg/L
fluoride	<0.1	mg/L
benzene	<0.1	µg/L
polycyclic aromatic hydrocarbons	<0.008	µg/L
chlorinated organic compounds	<1	µg/L
pesticides and biocides	< LOD	µg/L
pH	8.16
conductivity at 25 °C	228	µS/cm
hardness	0.83	mmol/L
LOD = limit of detection

Table 5. Mortality
Nominal Conc. in mg/L	Total number of fish used	Number of dead fish
		24 h	48 h	72 h	96 h
Blank control	7	0	0	0	0
100	7	0	0	0	0

Table 6. pH and O2 values
Nominal Conc. in mg/L	pH at t		O2 in mg/L at t
mg/L	0 h	24 h	48 h	72 h	96 h	0 h	24 h	48 h	72 h	96 h
Blank control	7.9	7.9	7.9	7.9	8	9.6	8.3	8.6	7.7	8.1
100	8	8	8	7.9	8	8.1	8	8.1	7.3	7.7

Table 7. Temperature
0 h	24 h	48 h	72 h	96 h
Temperature in °C
22.6	22.3	22	22.2	22.5

Table 9. Biological Results
Parameter	Value
NOEC	≥ 100 mg/L
LOEC	> 100 mg/L
96h LC50	> 100 mg/L

Validity criteria fulfilled:

yes

Remarks:

No mortality occurred in the blank control. The concentration of dissolved oxygen was at least 7.3 mg/L or 84.5 % throughout the test The highest variation pf pH was 0.1 units.

Conclusions:

In this study, the 96-h acute toxicity (mortality) to 7 fish (Danio rerio) was tested by using a static test design. None of the animals were immobilised in the treatment and in the blank control.
The following results for the test item were determined:
96h-NOEC ≥ 100 mg/L;
96h-LOEC > 100 mg/L;
96h-EC50 > 100 mg/L

Executive summary:

The 96-h acute toxicity to fish (Danio rerio) was determined by using a static test design. The test followed EU-Method C.1. resp. OECD Guideline 203 and it was performed as a limit test using the nominal concentration of 100 mg/L. None of the animals were immobilised in the treatment and in the blank control.

At the start and at the end of the test, the content of Magnesium in the test solutions was determined using ICP-OES. Only in the test solution at the end of the test a very low concentration of Magnesium was detectable. All other measured values are below the LOD. Therefore, the determination of the biological results was based on the nominal concentration.

Description of key information

The acute test (OECD 203) of Zebrafish (Danio rerio) to Magnesium fluoride was determined using static test system and nominal concentrations at controlled conditions. The study was conducted according to OECD 203 and followed OECD Principles of Good Laboratory Practice (GLP). No unusual observations or deviations from standard test protocol were noted. As a result, 96-h LC50 was calculated as >100 mg/L.

Based on the available data, the 96-h LC50-value was selected as a key value.

The data obtained from testing on freshwater species has been used as basis for assessment of effects in marine environment as well as for extrapolation of the measured effects to other compartments within the aquatic ecosystem (e.g. sediment) and soil.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L

Marine water fish

Marine water fish

Effect concentration:

100 mg/L

Additional information

The short-term toxicity to fish results obtained from the supporting read-across substance (sodium fluoride) has been provided.