bis(diethylamino)-N,N-diethylmethaniminium 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:

January 7, 2004 to February 10, 2004

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

Remarks:

OECD GLP

Analytical monitoring:

yes

Details on sampling:

Collected from the approximate center of the first replicate test vessel at the start of the test and the second replicate vessel at the end of the test.

Vehicle:

no

Details on test solutions:

Water used for the acclimation of test organisms and for all toxicity testing was carbon filtered, deionized water collected at T.R. Wilbury Laboratories in Marblehead, Massachusetts. Water was adjusted to a hardness of 160 to 180 mg/L as CaCO3 and stored in polyethylene tanks where it was aerated and recirculated through particle filters, activated carbon, and an ultraviolet sterilizer. Prior to use, the pH of the dilution water was adjusted to less than 8.0. A sample of dilution water collected at the start of the definitive test had a hardness of 168 mg/L as CaCO3. A 100 mg a.i./L stock solution was prepared (with correction for purity) by bringing 0.3144 g of test substance to 2,000 mL with dilution water in a Class A volumetric flask. This stock solution was mixed, and then used to prepare the test solutions by transferring an appropriate volume of stock solution directly to the test vessels and adjusting the total volume in each vessel to 250 mL with dilution water.

Test organisms (species):

Daphnia magna

Details on test organisms:

Juvenile daphnids, Daphnia magna, less than 24 hours old, employed as test organisms were from a single source and were identified using an appropriate taxonomic key. They were produced by an in-house culture of adult daphnids that were maintained under test conditions at T.R. Wilbury Laboratories. The original culture was obtained from Aquatic Biosystems Inc., Fort Collins, Colorado. At the conclusion of the test the control daphnids had an average wet weight of 0.3 mg (loading rate during the definitive toxicity test was less than or equal to 40 daphnids per liter).
Prior to testing, the daphnid culture was maintained in 100% dilution water under static-renewal conditions, and the test organisms were not treated for disease. No mortality was observed during the 48 hours prior to the beginning of the test and at the beginning of the test organisms were apparently free of disease, injuries, and abnormalities. The culture used to produce neonates for the definitive toxicity test produced young by day 7 and produced an average of at least 3 young/female/day during the 7 days prior to the start of the test.
During the 7 days prior to the beginning of the test, the temperature of the culture ranged from 20.4 to 20.6°C, the pH ranged from 7.1 to 7.6, and the dissolved oxygen concentration was at least 8.3 mg/L. Test organisms were fed the freshwater algae, Selenastrum capricornutum, and a mixture of yeast and trout chow once each day before the test. Daphnids were not fed during the test.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

168 mg/L as CaCO3

Test temperature:

19.0 to 20.1 °C

pH:

7.5 to 7.6

Dissolved oxygen:

8.5 to 9.3 mg/L

Conductivity:

630 to 690 μmhos/cm (mean = 640 μmhos/cm)

Nominal and measured concentrations:

0 (control), 13, 22, 36, 60, and 100 mg a.i./L
Measured: ND (none detected; control), 13, 21, 34, 61 and 99 mg a.i./L

Details on test conditions:

A range-finding test was conducted under static conditions with a control and five concentrations of test substance: 5.0, 10, 50, 100, and 500 mg a.i./L. After 48 hours, there was 100% survival in the control and at 5.0 and 10 mg a.i./L, 50% survival at 50 mg a.i./L, 20% survival at 100 mg a.i./L, and 0% survival at 500 mg a.i./L. A definitive test was initiated, but terminated after 24 hours because one test vessel was accidentally spilled.

The final definitive toxicity test was conducted under static conditions at 20 ± 1°C with five concentrations of test substance (13, 22, 36, 60, and 100 mg a.i./L) and a dilution water control. Twenty daphnids were randomly distributed among two replicates of each treatment. The test was performed in 300-mL glass beakers that contained 250 mL of solution. Test vessels were arranged in an incubator during the test using a random numbers table.
A 16-hour light and 8 hour dark photoperiod was automatically maintained with cool white fluorescent lights that provided a light intensity of approximately 150 footcandles. A 15-minute transition period was provided between dark and light. Aeration was not required to maintain dissolved oxygen concentrations above acceptable levels. The numbers of surviving organisms, the occurrence of immobility and sublethal effects, and the presence of insoluble material were determined visually and recorded after 0, 24, and 48 hours. Dead test organisms were removed when first observed.
Dissolved oxygen, pH, conductivity, and temperature were measured and recorded in each vessel at the beginning and end of the test. The temperature in a representative vessel was recorded continuously.

Reference substance (positive control):

not required

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

26 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Mortality/ Immobilization

Remarks on result:

other: 21 to 31 mg/L

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

22 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Remarks on result:

other: 18 to 25 mg/L

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

< 13 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Mortality/ Immobilization

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Details on results:

No insoluble material was observed during the definitive toxicity test. Mean measured test concentrations ranged from 94 to 102% of nominal concentrations and they were stable throughout this static exposure. All results were based on mean measured test concentrations. One hundred percent survival and no sublethal effects were observed in the control.

Results with reference substance (positive control):

NA

Reported statistics and error estimates:

Results of the toxicity test were interpreted by standard statistical techniques. The 24-hour LC50 and EC50 values could not be calculated because more than 50% of the daphnids were alive and unaffected at all tested concentrations. The 48-hour LC50 and EC50 values were calculated using the probit method (the slope of the concentration-response curve was calculated using the probit method). The no observed effect concentration was defined as the highest tested concentration of test substance that did not cause toxicant-related mortality or sublethal effects.

Measured concentrations of the test substance during the toxicity test with the daphnid, Daphnia magna

Nominal Concentration of the Test Substance (mg a.i./L)	Measured Concentration of the Test Substance (mg a.i./L)
	0 Hour	48 Hours	Mean	% Recovery
Test Media Samples
Control	ND	ND	ND	---
13	13	12	13	100
22	20	21	21	95
36	34	34	34	94
60	60	62	61	102
100	100	98	99	99
Matrix Spike Samples
36	36	36	36	100
	36	39
	36	35
Blank
0	ND	---	ND	---
ND:  none detected at or above the limit of quantitation.

Survival and sublethal effect data from the toxicity test with the test substance and the daphnid, Daphnia magna.

Mean Measured Concentration of  the Test Substance (mg a.i./L)	R	Number Alive			Number Affected^1
		0 hr	24 hr	48 hr	0 hr	24 hr	48 hr
Control	1	10	10	10	0	0	0
	2	10	10	10	0	0	0
13	1	10	10	9	0	0	0
	2	10	9	9	0	0	0
21	1	10	10	5	0	0	0
	2	10	10	6	0	0	1
34	1	10	9	5	0	0	3
	2	10	10	3	0	0	2
61	1	10	9	0	0	0	--
	2	10	6	1	0	0	1
99	1	10	6	0	0	0	--
	2	10	9	0	0	3	--

R:  Replicate

¹ Affected daphnids were immobilized

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of this study, exposure of daphnids to the test material resulted in a 48-hour LC50 value of 26 mg a.i./L (95 % confidence interval = 21 to 31 mg a.i./L) and a 48-hour EC50 value of 22 mg a.i./L (95 % confidence interval = 18 to 25 mg a.i./L).

Executive summary:

The acute toxicity of the test material to the daphnid, Daphnia magna, was investigated in accordance to the standardised guidelines OECD 202, under GLP conditions. 

The test was performed under static conditions with a control and five concentrations of test material at a temperature of 20 ± 1 °C.  The dilution water was deionized water and was adjusted to a hardness of 160 to 180 mg/L as CaCO3 and a pH less than 8.0.  Nominal concentrations of the active ingredient were: 0 mg/L (control), 13, 22, 36, 60, and 100 mg/L.  Mean measured concentrations were: ND (none detected; control), 13, 21, 34, 61, and 99 mg/L.  No insoluble material was observed during the definitive toxicity test.  Mean measured concentrations were used for all toxicity determinations.

Organisms used in the test were less than 24 hours old.  They were obtained from an in-house culture that was acclimated to test conditions.  All animals were in good condition at the beginning of the toxicity test.

Under the conditions of this study, exposure of daphnids to the test material resulted in a 48-hour LC50 value of 26 mg a.i./L (95 % confidence interval = 21 to 31 mg a.i./L) and a 48-hour EC50 value of 22 mg a.i./L (95 % confidence interval = 18 to 25 mg a.i./L).

Description of key information

Ward, Wyskiell, Boeri (2003)

Under the conditions of this study, exposure of daphnids to the test material resulted in a 48-hour LC50 value of 26 mg a.i./L (95 % confidence interval = 21 to 31 mg a.i./L) and a 48-hour EC50 value of 22 mg a.i./L (95 % confidence interval = 18 to 25 mg a.i./L).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

22 mg/L

Additional information

Ward, Wyskiell, Boeri (2003)

The acute toxicity of the test material to the daphnid, Daphnia magna, was investigated in accordance to the standardised guidelines 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).

The test was performed under static conditions with a control and five concentrations of test material at a temperature of 20 ± 1 °C.  The dilution water was deionized water and was adjusted to a hardness of 160 to 180 mg/L as CaCO3 and a pH less than 8.0.  Nominal concentrations of the active ingredient were: 0 mg/L (control), 13, 22, 36, 60, and 100 mg/L.  Mean measured concentrations were: ND (none detected; control), 13, 21, 34, 61, and 99 mg/L.  No insoluble material was observed during the definitive toxicity test.  Mean measured concentrations were used for all toxicity determinations.

Organisms used in the test were less than 24 hours old.  They were obtained from an in-house culture that was acclimated to test conditions.  All animals were in good condition at the beginning of the toxicity test.

Under the conditions of this study, exposure of daphnids to the test material resulted in a 48-hour LC50 value of 26 mg a.i./L (95 % confidence interval = 21 to 31 mg a.i./L) and a 48-hour EC50 value of 22 mg a.i./L (95 % confidence interval = 18 to 25 mg a.i./L).