Tetrabutylammonium bromide

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Justification for type of information:

Experimental test result performed according to the guideline.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

no

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 25, 50, 100, 200, and 400 mg/L
- Sampling method: test chemical was analysed at 0 hours and 48 hours of exposure duration - Sample storage conditions before analysis test chemical was analysed immediately after sampling

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 500 mg of test item was transferred to 500 ml volumetric flask and made up to 1000 mL using M7 medium (stock). From the stock solution 25 ml, 50 ml, 100 ml, 200 mL and 400ml were made up to 1 litre in a 1000 mL measuring cylinder using M7 medium. Thus, concentrations of 25, 50, 100, 200 and 400 mg/L were achieved.
- Controls: M7 medium (Control),
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Not applicable
- Concentration of vehicle in test medium (stock solution and final test solution(s) or suspension(s) including control(s)): Not applicable

Test organisms (species):

Daphnia magna

Details on test organisms:

- Common name: Water flea
- Strain: Straus
- Source: Daphnia obtained from DTU. Later test system was sub-cultured in the test facility and same was used for the study
- Age at study initiation (mean and range, SD): <24 h
- Food: No feeding was given suring study

ACCLIMATION
- Acclimation period: Parent daphnias were acclimitsed atleast 2 weeks before the study
- Acclimation conditions (same as test or not): Yes (healthy gravid females were acclimatized)
- Type and amount of food: Food was provided during acclimatization.
- Health during acclimation (any mortality observed): healthy no mortality was observed

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

Immoblisation was observed at 0hr 24hr and 48 hr

Hardness:

160 mg/L

Test temperature:

20 - 21 °C

pH:

7.2 - 7.6

Dissolved oxygen:

7.2 - 6.8 mg/l

Salinity:

Not applicable

Nominal and measured concentrations:

Nominal concentrations: 25, 50, 100, 200 and 400 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beaker
- Aeration: No aeration during experiment
- Material, size, headspace, fill volume: 25 ml of glass beaker filled with 20 ml media having headspace of 5 ml
- No. of organisms per vessel: 10 daphnids

OTHER TEST CONDITIONS
- Photoperiod:16 hours light and 8 hours dark

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (K2Cr2O7)

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

98.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: CI- 87.21-110.4 mg/l

Details on results:

- Behavioural abnormalities: None
- Mortality of control: No mortality was observed in control
- Other adverse effects control: None
- Immobilisation of control: No immobilisation was observed in control
- Abnormal responses: None

Results with reference substance (positive control):

- Results with reference substance valid?
Yes valid
EC50: 0.690 mg/L
95% confidence limits: Upper limit = 0.749 mg/L
Lower limit = 0.631 mg/L

Reported statistics and error estimates:

48h EC50 value with 95% confidence limits (upper limit, lower limit) were calculated by probit analysis

Daphnia immoblisation

Concentration (mg/L)	Daphnia Immobilization
	24 hours	48 hours	Cumulative Immobilization(%)
Definitive test
Control	0	0	0.0
25	0	1	5
50	1	2	15
100	6	7	65
200	7	9	80
400	10	8	90

	Replication	Immobilization (Numbers)		Cumulative Immobilization (Numbers)  for period of 48 hours
		24 hours	48 hours
Control	R1	0	0	0
	R2	0	0
	R3	0	0
	R4	0	0
25	R1	0	0	1
	R2	0	0
	R3	0	1
	R4	0	0
50	R1	1	0	3
	R2	0	1
	R3	0	1
	R4	0	0
100	R1	2	2	13
	R2	0	2
	R3	3	2
	R4	1	1
200	R1	2	3	16
	R2	1	2
	R3	2	1
	R4	2	3
400	R1	2	2	18
	R2	0	4
	R3	5	0
	R4	3	2

Concentration (mg/L)	pH		Temperature (⁰C)		Dissolved oxygen (mg/L)
	0 hour	48 hour	0 hour	48 hour	0 hour	48 hour
Definitive test
Control	7.4	7.3	21	20	7.1	7.0
25	7.5	7.2	20	20	6.9	6.9
50	7.6	7.5	20	21	7.0	6.8
100	7.6	7.2	20	21	7.6	6.9
200	7.6	7.3	21	20	6.9	6.9
400	7.6	7.5	21	20	7.2	6.8

Validity criteria fulfilled:

yes

Conclusions:

Based on nominal concentrations, experimental median effective Concentrations [EC-50 (48 h)] for test chemical on test daphnia was observed to be 98.1 mg/l.

Executive summary:

This study was designed (as per OECD 202, adopted in 2004) to assess the acute toxicity of test chemical following exposure of daphnids up to 48h by static method.The brood daphnids were acclimatized > 2weeks prior to the test item exposure. Less than 24 h old daphnids were collected from the acclimatized gravid females and exposed to the test item. After exposure on day 0, daphnids were observed for immobilization at 24 and 48 h. M7 medium was used as control, and the same was used for test item formulation and test medium . 25 mL glass beakers having a solution volume of 20 mL were used in the test. A main study (using a spacing factor of 2) was conducted using 0 (control), 0 (vehicle control), 25, 50, 100, 200, and 400 mg/L concentrations. 4 replicates/concentration having 5 daphnids/replicate was used for the main study. Normal behavioural response and no immobilization (0% mortality) were observed up to 48 h followed by control groups, and 5%, 15%, 65%, 80, and 90% mortality were observed in the test concentrations of 25, 50, 100, 200, and 400 mg/L, respectively. The analytial monitoring was done, and the test chemicals were maintained within the acceptable range i.e., 80 -120% of the nominal concentrations. Hence the results were based on nominal concentration, since the deviation in the initial measured concentration didn’t exceed 20%. Environmental parameters such as pH (7.2-7.8), temperature (20-21 °C), dissolve oxygen (6.8-7.2 mg/L), hardness (160 mg CaCO₃/L), photoperiod (16 h light- 8 h dark) and light intensity (1330-1352 Lux) was maintained in acceptable range throughout the test. Feed was not provided during the test. The 48-h EC₅₀of test chemical to daphnid,Daphnia magnaare 98.1mg/L. The 48-h EC₅₀of reference item (Potassium dichromate) to daphnid,Daphnia magna(found to be in acceptable range) is 0.690 mg/L. Hence, the results of the test with reference item establish the acceptability of the test system response, test procedures followed and results obtained with test item. Thus, based on the EC50 value, test chemical can considered as toxic and hazardous to aquatic invertebrates. Thus, chemical can be classified into aquatic chronic category 3 as per CLP classification criteria

Description of key information

This study was designed (as per OECD 202, adopted in 2004) to assess the acute toxicity of test chemical following exposure of daphnids up to 48h by static method.The brood daphnids were acclimatized > 2weeks prior to the test item exposure. Less than 24 h old daphnids were collected from the acclimatized gravid females and exposed to the test item. After exposure on day 0, daphnids were observed for immobilization at 24 and 48 h. M7 medium was used as control, and the same was used for test item formulation and test medium . 25 mL glass beakers having a solution volume of 20 mL were used in the test. A main study (using a spacing factor of 2) was conducted using 0 (control), 0 (vehicle control), 25, 50, 100, 200, and 400 mg/L concentrations. 4 replicates/concentration having 5 daphnids/replicate was used for the main study. Normal behavioural response and no immobilization (0% mortality) were observed up to 48 h followed by control groups, and 5%, 15%, 65%, 80, and 90% mortality were observed in the test concentrations of 25, 50, 100, 200, and 400 mg/L, respectively. The analytial monitoring was done, and the test chemicals were maintained within the acceptable range i.e., 80 -120% of the nominal concentrations. Hence the results were based on nominal concentration, since the deviation in the initial measured concentration didn’t exceed 20%. Environmental parameters such as pH (7.2-7.8), temperature (20-21 °C), dissolve oxygen (6.8-7.2 mg/L), hardness (160 mg CaCO₃/L), photoperiod (16 h light- 8 h dark) and light intensity (1330-1352 Lux) was maintained in acceptable range throughout the test. Feed was not provided during the test. The 48-h EC₅₀of test chemical to daphnid,Daphnia magnaare 98.1mg/L. The 48-h EC₅₀of reference item (Potassium dichromate) to daphnid,Daphnia magna(found to be in acceptable range) is 0.690 mg/L. Hence, the results of the test with reference item establish the acceptability of the test system response, test procedures followed and results obtained with test item. Thus, based on the EC50 value, test chemical can considered as toxic and hazardous to aquatic invertebrates. Thus, chemical can be classified into aquatic chronic category 3 as per CLP classification criteria

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

98.1 mg/L

Additional information

Based on the various experimental data for the target chemical study have been reviewed to determine the nature of test chemical on the mobility and growth of aquatic invertebrate. The studies are as mentioned below:  

 

This study was designed (as per OECD 202, adopted in 2004) to assess the acute toxicity of test chemical following exposure of daphnids up to 48h by static method.The brood daphnids were acclimatized > 2weeks prior to the test item exposure. Less than 24 h old daphnids were collected from the acclimatized gravid females and exposed to the test item. After exposure on day 0, daphnids were observed for immobilization at 24 and 48 h. M7 medium was used as control, and the same was used for test item formulation and test medium . 25 mL glass beakers having a solution volume of 20 mL were used in the test. A main study (using a spacing factor of 2) was conducted using 0 (control), 0 (vehicle control), 25, 50, 100, 200, and 400 mg/L concentrations. 4 replicates/concentration having 5 daphnids/replicate was used for the main study. Normal behavioural response and no immobilization (0% mortality) were observed up to 48 h followed by control groups, and 5%, 15%, 65%, 80, and 90% mortality were observed in the test concentrations of 25, 50, 100, 200, and 400 mg/L, respectively. The analytial monitoring was done, and the test chemicals were maintained within the acceptable range i.e., 80 -120% of the nominal concentrations. Hence the results were based on nominal concentration, since the deviation in the initial measured concentration didn’t exceed 20%. Environmental parameters such as pH (7.2-7.8), temperature (20-21 °C), dissolve oxygen (6.8-7.2 mg/L), hardness (160 mg CaCO₃/L), photoperiod (16 h light- 8 h dark) and light intensity (1330-1352 Lux) was maintained in acceptable range throughout the test. Feed was not provided during the test. The 48-h EC₅₀of test chemical to daphnid,Daphnia magnaare 98.1mg/L. The 48-h EC₅₀of reference item (Potassium dichromate) to daphnid,Daphnia magna(found to be in acceptable range) is 0.690 mg/L. Hence, the results of the test with reference item establish the acceptability of the test system response, test procedures followed and results obtained with test item. Thus, based on the EC50 value, test chemical can considered as toxic and hazardous to aquatic invertebrates. Thus, chemical can be classified into aquatic chronic category 3 as per CLP classification criteria

First study was supported by the second experimental from peer reviewed journal. Aim of this study was to evaluate the effect of test chemical on the mortality rate of aquatic arthropod Echinogammarus tibaldii. Organisms of the species E. tibaldii Pink & Stock (Crustacea, Amphipoda) were collected near the spring of the river Vera (L'Aquila, Italy). The animals were screened from mayor detritus, transported to the laboratory under continuous aeration and held for acclimation in cool, aerated water in 20-L aquaria. Mature adult male individuals obtained from precopula pairs and kept for about 3 d in cool "reconstituted water'". Received artificial oxygenation and were fed on dry poplar leaves previously soaked in spring water in order to enrich them with fungi and bacteria. The definitive tests were carried out in duplicate by adding 20 animals (Mature adult male) in each I-L glass jar containing 250 mL of each precooled and aerated solution. During the test, carried out in static conditions and without oxygenation, the animals were not fed. After the exposure of test chemical for 24 hrs with aquatic arthropod Echinogammarus tibaldii, the LC50 was determine to > 2000 mg/l. Based on the LC50 value, chemical consider to be nontoxic and not classified as per the CLP classification criteria.

 

Thus based on the experimental study which is according to the guideline, it was concluded that the test chemical was toxic and the can be consider to be classified as aquatic chronic 3 category as per the CLP classification criteria.