Thiamine hydrochloride

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:

21 October 1992 to 16 November 1992

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:

1984

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Composite samples (about 150 mL in duplicate) of each test concentration were drawn by mixing identical volumes of the test solutions taken from the approximate centre of the test vessels.
- They were taken immediately before exposure and after 48 hours exposure and kept at -18 to -22 °C until analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- 199.8 mg test material was mixed and made up to 2000 mL with water.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain/clone: Straus 1820
- Source: In house
- Age: 0-24 h of age
- Feeding during test: no

ACCLIMATION
- Cultures of daphnia are maintained in glass vessels containing approximately 2.5 L of reconstituted water at 20 ± 1 °C (water is renewed partially thrice weekly).
- Feeding: At each renewal the daphnia are fed with a suspension of green algae (Scenedesmus subspicatus) supplemented by a suspension of TETRAMIN-extract in such quantities that food is consumed after 24 hours.
- 24 hours before the beginning of the exposure period, reproductive daphnia are separated from the young by sieving all individuals through a 800 µm sieve. This operation is repeated immediately before the exposure and the young (0-24 h of age) are retained for the test.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

240 mg CaCO3/L

Test temperature:

20 ± 1 °C

pH:

6.7-7.8

Dissolved oxygen:

98-100 %

Nominal and measured concentrations:

Nominal: 10, 18, 32, 58, 100 mg/L
Measured: 9.6, 17.1, 31.0, 56.2, 97.9 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Beakers covered with watch glasses
- Material, size, headspace, fill volume: 100 mL solution per beaker
- Aeration: No
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted water containing: 65 mg NaHCO3, 294 mg CaCl2.2H2O, 123 mg MgSO4.7H2O and 6 mg KCl in 1000 mL bidistilled water.
- The water was aerated-with clean air for at least 24 hours before use.
- Calculated amounts of the stock solution to produce the desired test concentrations were given into the water and were homogeneously distributed. The daphnia were then transferred into the beakers. The test material was homogeneously distributed in the test vessels at all test times and test concentrations.
- Intervals of water quality measurement: The oxygen content, pH and temperature were measured at 0 and 48 hours.

OTHER TEST CONDITIONS
- Photoperiod: no lighting

EFFECT PARAMETERS MEASURED
- Immobilisations were recorded after 24 and 48 hours exposure and are given in Table 2.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

58 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

58 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Immobilisations in the blank: 0 %
- All values are based on nominal concentrations
- Results can be seen in Table 2.

Reported statistics and error estimates:

No statistical analysis was performed.

 Table 1: Analytical determination of test material concentrations

Nominal concentration (mg/L)	Measured concentrations
	Initial (0 h)		End (48 h)		Average
	mg/L	%	mg/L	%	mg/L	%
Blank	<0.4	-	<0.4	-	<0.4	-
10	9.5	95	9.6	96	9.6	96
18	17.1	95	17.1	95	17.1	95
32	31.1	97	30.8	96	31.0	97
58	56.0	97	56.3	97	56.2	97
100	98.2	98	97.6	98	97.9	98

Table 2: Immobilisation (Initial numbers of daphnia = 20/test concentration)

Nominal concentration (mg/L)	Immobilisation after 48 h in vessel:						Immobilisation after 48 h in vessel:
	1	2	3	4	Total	%	1	2	3	4	Total	%
Blank	0	0	0	0	0	0	0	0	0	0	0	0
10	1	0	0	0	1	5	0	0	0	0	0	0
18	0	0	0	0	0	0	1	0	0	0	1	5
32	0	0	0	0	0	0	0	0	0	0	0	0
58	0	0	0	0	0	0	0	0	0	0	0	0
100	0	0	0	0	0	0	1	2	1	1	5	25

Validity criteria fulfilled:

not specified

Conclusions:

Under the conditions of this study, the 24 and 48-h EC50 was >100 mg/L. The 48-h NOEC was 58 mg/L.

Executive summary:

The potential of the test material to cause aquatic toxicity to invertebrates was determined in accordance with the standardised guideline OECD 202, under GLP conditions.

Daphnia magna were exposed to the test material for a period of 48 hours, immobilisation was determined at 24 and 48 hours. The daphnia were exposed to the nominal concentrations of: 10, 18, 32, 58 and 100 mg/L. Analytical verification of the test material concentrations was performed using UV-spectroscopy.

There was no immobilisation observed in the control group.

Under the conditions of this study, the 24 and 48-h EC50 was >100 mg/L. The 48-h NOEC was 58 mg/L.

Description of key information

Under the conditions of this study, the 24 and 48-h EC50 was >100 mg/L. The 48-h NOEC was 58 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

The potential of the test material to cause aquatic toxicity to invertebrates was determined in accordance with the standardised guideline OECD 202, under GLP conditions. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

Daphnia magna were exposed to the test material for a period of 48 hours, immobilisation was determined at 24 and 48 hours. The daphnia were exposed to the nominal concentrations of: 10, 18, 32, 58 and 100 mg/L. Analytical verification of the test material concentrations was performed using UV-spectroscopy.

There was no immobilisation observed in the control group.

Under the conditions of this study, the 24 and 48-h EC50 was >100 mg/L. The 48-h NOEC was 58 mg/L.