(hexadecylamidopropyl)trimethylammonium chloride

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:

2015-05-08 to 2015-05-13

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:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

All concentration levels and the control were analytically verified via LC-MS/MS at the start (0 and 24 hours) and at the end of both exposure intervals (24 and 48 hours). At the start of the exposure intervals (0 and 24 hours), sampling was carried out after preparation of the test concentrations. At the end of the exposure intervals (24 and 48 hours), samples were taken directly from the test vessels.- Sample storage conditions before analysis: room temperature

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
A stock solution (1600 µg/L of the test item were weighed out) was prepared with dilution water (river water as specified below) two days before the beginning of the pre-treatment of the test vessels and before the start both exposure intervals (at -72, -48 and -24 h).
The stock solution was stirred with approximately 1100 rpm at a temperature of 40 ± 2°C for 24 ± 1 hours. Thereafter, the stock solution was stirred for further 24 ± 1 hours with approximately 1100 rpm at the temperature of the test (19 - 21 °C).5 test item concentrations in a geometric series with a separation factor of 2 were prepared by diluting the stock solution of 1600 µg/L with natural river water.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain: Daphnia magna STRAUS (Clone 5)
- Source: Institut für Wasser-, Boden- und Lufthygiene (WaBoLu), 14195 Berlin, Germany
- Age at study initiation (mean and range, SD): 2 to 24 hours old daphnids
- Method of breeding: In glass vessels (2 - 3 L capacity) with approximately 1.8 L culture medium, at 20 ± 2°C, in an incubator, 16 h illumination, light intensity of max. 20 µE m-2 s-1
- Feeding during test: no

ACCLIMATION
- Acclimation period: At least 2 hours in river water
- Acclimation conditions (same as test or not): same
- Type and amount of food: culture daphnids are fed at least 5 times per week ad libitum with a mix of unicellular green algae, e.g. Pseudokirchneriella subcapitata and Desmodesmus subspicatus, with an algae cell density of > 1E06 cells/mL. The algae are cultured at the test facility

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

255 - 260

Test temperature:

19 - 20 °C

pH:

8.32 - 8.51

Dissolved oxygen:

7.30 - 9.19 mg/L

Nominal and measured concentrations:

nominal: 96.0, 192, 384, 768, 1536 µg/L
measured (geom. mean): 26.6, 35.9, 61.4, 460, 1144 µg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers (4 (ID) x 7 (H) cm) with a capacity of 50 mL, loosely covered with watch glasses
- Renewal rate of test solution (frequency/flow rate): renewal after 24 h- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
The test vessels were pre-treated with the appropriate test solutions for 24 hours under test conditions to saturate the glass walls with sorbed test item. Before the start of the exposure intervals, the test containers were emptied and refilled with freshly prepared test solutions.

TEST MEDIUM / WATER PARAMETERS
river water as specified in section "any other information on materials and methods"

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16/8 h light/dark cycle
- Light intensity: Diffuse light; light intensity of max. 20 µE m-2 s-1

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
Immobilisation was determined in all groups after 24 and 48 hours.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
Range finding study
- Test concentrations: 9.60, 96.0 and 960 µg a.i./L, nominal, prepared in natural river water
- Results used to determine the conditions for the definitive study: 100% immobilisation at 960 µg a.i./L, 0% immobilisation at 96.0 and 9.6 µg a.i./L

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

61.4 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Remarks on result:

other: 95% c.l. 58.9 - 64.1

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

64.6 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Remarks on result:

other: 95% c.l. 62.7 - 66.7

Details on results:

- Mortality of control: 0%

Results with reference substance (positive control):

- Results with reference substance valid? yes
- EC50: 1.92 mg/L (CI 1.71 - 2.29 mg/L)

Reported statistics and error estimates:

The EC100-values (after 24 and 48 hours) were estimated directly from the observation data, without mathematical calculation. The EC10- and the EC50-values (after 24 and 48 hours) were calculated by sigmoidal dose-response regression. The respective 95 % confidence limits were calculated from the standard error and the t-distribution. All calculations were carried out from the best-fit values with the software GraphPad Prism5.

Immobilisation Ratesafter 24 and 48 hours ofExposure in the Definitive Test

(n = 20, divided into 4 replicates with 5 daphnids each)

Nominal test item concentration   [µg/L]	Geometric mean measured test item concentration [µg/L]	IMMOBILISATION [%]
		24 hours					48 hours
		Replicates					Replicates
		1	2	3	4	MV	1	2	3	4	MV
1600	1144	100	100	100	100	100	100	100	100	100	100
800	460	100	100	100	100	100	100	100	100	100	100
400	61.4	40	20	20	0	20	80	40	20	0	35
200	35.9	0	0	0	0	0	0	0	0	0	0
100	26.6	0	0	0	0	0	0	0	0	0	0
Control		0	0	0	0	0	0	0	0	0	0

 

Validity criteria fulfilled:

yes

Conclusions:

The 48-hour EC50 of C16 Alkylamidopropyltrimethylammonium Chloride to Daphnia magna was 61.4 µg a.i./L (95 % confidence limits: 58.9 – 64.1 µg/L; measured concentration, geom. mean).

Executive summary:

The 48-hr-acute toxicity of C16 Alkylamidopropyltrimethylammonium Chloride to Daphnia magna was studied under semi-static conditions according to OECD Guideline 202 (2004).  Daphnids were exposed to control and test chemical at nominal concentrations of 96.0, 192, 384, 768, 1536 µg a.i./L (corresponding to 26.6, 35.9, 61.4, 460, 1144 µg/L geom. mean measured concentrations) in natural river water for 48 h.

The test item is known to sorb to organic and inorganic materials by different mechanisms. The sorption processes are mostly non-linear, means are concentration dependent. Due to these properties the test item is difficult to test in synthetic water (e.g. sorption to the test organisms and glass walls of the test vessels) and results from such tests depend from the test settings applied. Therefore, natural river water was used which contains particulate as well as dissolved organic carbon to which the test item can sorb partially to reduce the difficulties encountered in tests with synthetic water (e.g. preventing that the test item settles onto surfaces). The sorbed fraction of the test item is difficult to extract from the test system which normally leads to low analytical recoveries at the end of the exposure. Nevertheless the test item is present in the test system and therefore available for exposure (dissolved in water and sorbed).

Additionally, the test vessels were pre-treated with the test solutions one day before the start of the respective exposure interval to saturate the glass walls with sorbed test item in the definitive test.This procedure was carried out to achieve stable exposure concentrations in the test vessels and to reduce losses of the test item by adsorption onto the glass walls.

Mortality/immobilization was observed daily. 

The 48-hour EC50 was 61.4 µg a.i./L (95 % confidence limits: 58.9 – 64.1 µg/L)

 

This study is classified as acceptable and satisfies the guideline requirements for an acute toxicity study with freshwater invertebrates.

 

Results Synopsis

Test Organism Age: max. 24 h old daphnids

Test Type: Static Renewal

 

EC50: 61.4 µg a.i./L; 95% C.I. : 58.9 – 64.1 µg/L

Endpoint(s) Effected:  mobility

Description of key information

48 h EC50=61.4 µg a.i./L (95% confidence limits: 58.9 – 64.1 µg/L) (geom. mean measured); Daphnia magna, semi-static, river water; OECD Guideline 202 (2004); RL1, GLP

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

61.4 µg/L

Additional information

The 48-hr-acute toxicity of C16 Alkylamidopropyltrimethylammonium Chloride to  Daphnia magna was studied under semi-static conditions according to OECD Guideline 202 (2004).  Daphnids were exposed to control and test chemical at nominal concentrations of 96.0, 192, 384, 768, 1536 µg a.i./L (corresponding to 26.6, 35.9, 61.4, 460, 1144 µg/L geom. mean measured concentrations) in natural river water for 48 h.

The test item is known to sorb to organic and inorganic materials by different mechanisms. The sorption processes are mostly non-linear, means are concentration dependent. Due to these properties the test item is difficult to test in synthetic water (e.g. sorption to the test organisms and glass walls of the test vessels) and results from such tests depend from the test settings applied.Therefore, natural river water was usedwhich contains particulate as well as dissolved organic carbon to which the test item can sorb partially to reduce the difficulties encountered in tests with synthetic water (e.g. preventing that the test item settles onto surfaces). The sorbed fraction of the test item is difficult to extract from the test system which normally leads to low analytical recoveries at the end of the exposure. Nevertheless the test item is present in the test system and therefore available for exposure (dissolved in water and sorbed).

Additionally, the test vessels were pre-treated with the test solutions one day before the start of the respective exposure interval to saturate the glass walls with sorbed test item in the definitive test.This procedure was carried out to achieve stable exposure concentrations in the test vessels and to reduce losses of the test item by adsorption onto the glass walls.

Mortality/immobilization was observed daily. 

The 48-hour EC50 was 61.4 µg a.i./L (95% confidence limits: 58.9 – 64.1 µg/L)