Boron doped barium europium strontium silicate, orthorombic

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:

Biological part: 2016-07-27 to 2016-07-29 analytical part 2016-08-11 to 2016-08-26

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:

version adopted 2004-04-13

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

sampling at start of study (duplicate samples) and at end of study (48 hrs; duplicate samples after pooling the content of test beaker)

Vehicle:

no

Details on test solutions:

Reconstituted water according to ELENDT (1990):
Macro nutrients (mg/L):
CaCI2 x 7 H20 293.80
MgSO4 x 7 H20 123.30
KCI 5.80
NaHCO3 64.80
Na2SiO3 x 9H20 10.00
NaNO3 0.27
KH2PO4 0.14
K2HPO4 0.18

Trace elements (µg/L):
H3BO3 2860
MnCl2*4H20 361
LiCl 306
RbCl 71
SrCl2*6H20 152
NaBr 16
Na2MoO4 *2H2O 63
CuCl2*2H20 17
ZnCl2 13
CoCl2*6H20 10
KI 3.3
Na2SeO3 2.2
NH4VO3 0.6
Na2EDTA*2H20 2500
FeSO4*7H20 1000

Vitamins (µg/L):
Thiamine 75.00
B12 1.00
Biotin 0.75

Calculated water hardness 2.5mmol/L as caCO3
Calculated alkalinity: 0.9 mmol/L

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Straus)
- Source: inhouse laboratory culture of study institute
- Age at study initiation (mean and range, SD): not older than 17.5 hours

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

250 mg/L as CaCO3

Test temperature:

21°C

pH:

7.9 to 8.8 at test start
7.4 to 7.5 at test end

Dissolved oxygen:

6.8 to 9.0 mg/L at start
8.7 to 8.9 mg/L at end

Salinity:

alkalinity (calculated) = 0.9 mmol/L

Nominal and measured concentrations:

no concentration measured of test item as test item is insoluble. nominal concentration 100 mg/L

measured concentrations of ingredients

barium t=0 | barium t=48 h
_________________________
2.07 mg/L | 1.97 mg/l
_________________________
strontium t=0 | strontium t=48 h
29.9 mg/L | 29.32 mg/L

Details on test conditions:

TEST SYSTEM
20 daphnids per control and test concentration, 4 groups wih 5 individuals each. Each group is introduced in 60ml test medium

Dosage of test item: preparation of 100mg/L solution: 48.6 mg of test were mixed with 486 mL test water. The solution was ultrasonicated for 10 minutes and then stirred for 23.5 hours in the dark. Undissolved particles where separated by filtration. Resulting pH value of solution was 9.5 and readjusted to 8.8 with 2M Hcl.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 2.02 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: Based on concentration of Barium (mean value of analytical concentartion at start and end of experiment)

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 29.61 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: based on concentration of strontium, mean value of measured concentration (mean value of analytical concentration at begin and end of test)

Results with reference substance (positive control):

In the most recent test (dated january 2016) EC50 after 24 hrs exposure of potassiumdichromate was measured as 1.58 mg test item /L (CI 95% 1.32-1.92) This is consistent with reference values given in OECD guideline 202 (EC50 (24 hrs) between 0.6 amd 2.1 mg test item/L

Reported statistics and error estimates:

as the test is a limit test with no effects, no statistical methods are required

Purpose

The purpose of this assay was to identify the aquatic toxicity potential of the test material in Daphnia magna straus to provide a rational basis for hazard estimation for the test item in aquatic environments.

 

Study design

For this purpose, juvenile Daphnia magna were exposed to an aqueous test material preparation over 48 hours, under defined conditions. The study comprised of four vessels per concentration containing five Daphnia magna, i.e. 20 Daphnia per concentration. The daphnia were observed for immobilization for up to 48 hours. The test was conducted as a limit test with a nominal concentrations of 100 mg/L for test substance. No higher concentration could be tested due to limit of solubility of test item The analytical check of the concentrations was performed at the start and at the end of the study using ICP-OES. The GLP study was performed according to OECD TG 202.

 

Results

The follwing results have been obtained after an exposure for 48 hours:

 

Nominal concentration Immobilization immobilized / exposed
[mg/L]	24 hours	48 hours
100.0	0/20	0/20

No daphnia magna exposed to an aqueous preparation of the nominal concentration of  100 mg/L were immobilized.

Consequently following endpoints after 24 hrs and 48 hrs exposure time were derived

24 h EC50 > 100 mg/L 

48 h EC50 > 100 mg/L 

NOEC ≥ 100 mg/L

LOEC >  100 mg/L

 

Conclusions

Under the given experimental conditions, the 48 hours EC50 to Daphnia magna is > 100 mg/L.

 

 

Validity criteria fulfilled:

yes

Conclusions:

Under the described experimental conditions, the EC50 of test substance in Daphnia magna is > 100 mg/L for 48 hrs exposure time.

Description of key information

EC50 after 48 hrs exposure time > 100 mg/L, NOEC ≥ 100 mg/L

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

A GLP study according to OECD 202 is available. Juvenile Daphnia magna were exposed to an aqueous test material preparation over 48 hours under defined conditions in a limit test.

The analytical check of the concentrations of constituents with significant release was performed at the start and at the end of the study. Under the given experimental conditions, the EC50 to daphnia magna is > 100 mg/L (nominal).