bis(diethylamino)-N,N-diethylmethaniminium chloride

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 7, 2004 to February 25, 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes

Remarks:

OECD GLP

Analytical monitoring:

yes

Details on sampling:

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:

Dilution 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 40 to 48 mg/L as CaCO3 and stored in polyethylene tanks, where it was aerated and recirculated through particle filters, activated carbon, and an ultraviolet sterilizer. A sample of dilution water collected at the start of the definitive test had a hardness of 44 mg/L as CaCO3.

Appropriate amounts of the test substance (with correction for purity) were added directly to dilution water to formulate the test concentrations. Nominal concentrations of the active ingredient were 0 (control), 65, 110, 180, 300, and 500 mg a.i./L.

Test organisms (species):

Pimephales promelas

Details on test organisms:

Juvenile fathead minnow, Pimephales promelas, employed as test organisms were from a single source and were identified using an appropriate taxonomic key. They were procured from a commercial supplier (Aquatic Biosystems, Fort Collins, CO, USA). Prior to testing, the fish were maintained under flow-through conditions in a 220-L polyethylene tank. During acclimation, fish were not treated for disease and they were free of apparent disease, injuries and abnormalities at the beginning of the test. Fish were fed dry commercial fish food once per day except during the 48 hours preceding the test, and they were not fed during the test. During the 14-day period before the start of the test, the acclimation temperature range was 22.2 to 22.8°C and the dissolved oxygen concentration was always at least 8.0 mg a.i./L. Mortality during the last 48 hours of acclimation was 0%. At the conclusion of the test, the control fish had an average wet weight of 0.23 g (loading rate was 0.15 g/L) and they ranged in length from 2.4 to 3.8 cm.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Hardness:

44 mg/L as CaCO3 (at study start)

Test temperature:

21.4 - 22.1°C

pH:

7.2 - 7.8

Dissolved oxygen:

7.1 - 9.3 mg/L

Conductivity:

150 to 330 μmhos/cm

Nominal and measured concentrations:

Nominal: 0 (control), 65, 110, 180, 300 and 500 mg a.i./L
Mean measured: ND (not detected at or above the limit of quantitation of 0.095 mg a.i./L; control), 65, 110, 190, 310, and 510 mg a.i./L

Details on test conditions:

A range-finding test with test substance 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 96 hours there was 100% survival in the control and at 5.0, 10, 50, and 100 mg a.i./L, and 0% survival at 500 mg a.i./L. No sublethal effects or insoluble material were observed at any tested concentration.

The definitive toxicity test was conducted under static conditions at 22 ± 1°C with five concentrations of test substance and a dilution water control. Appropriate amounts of the test substance were added directly to dilution water to formulate the test concentrations. Nominal concentrations of the active ingredient were 0 mg a.i./L (control), 65, 110, 180, 300, and 500 mg a.i./L.

Twenty fathead minnows were randomly distributed among two replicates of each treatment and control. The test was performed in 20-liter glass aquaria that contained 15 liters of test solution (water depth was approximately 18 cm). Test vessels were randomly arranged in a water bath during the 96-hour test (random numbers tables were used to add test organisms to test vessels, to select the location of each vessel, as well as the assignment of test concentrations).
A 16-hour light and 8-hour dark photoperiod was automatically maintained with cool white fluorescent lights that provided a light intensity of approximately 42 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 sublethal effects, and the presence of insoluble material were determined visually and recorded after 0, 24, 48, 72, and 96 hours.
Dissolved oxygen, pH, conductivity and temperature were measured and recorded daily in each test vessel. The temperature in a control vessel was recorded continuously during the test.

Reference substance (positive control):

not required

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

320 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: 280-370 mg/L

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

220 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: 180-260 mg/L

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

190 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: 160-220 mg/L

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

160 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: 140-190 mg/L

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

110 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Details on results:

No insoluble material was observed at any tested concentration during the definitive toxicity test. Mean measured concentrations were 100 to 107% of nominal concentrations. All results were based on mean measured test concentrations. One hundred percent survival and no sublethal effects were observed in the control.

During the definitive toxicity test the conductivity ranged from 150 to 330 micromhos/cm (increasing with test substance concentration, mean = 210 micromhos/cm), the pH ranged from 7.2 to 7.8, the temperature ranged from 21.4 to 22.1°C (mean = 21.8°C), and the dissolved oxygen concentration ranged from 7.1 to 9.3 mg/L (mean = 8.3 mg/L).

Reported statistics and error estimates:

Results of the toxicity test were interpreted by standard statistical techniques. The LC50 values and the slope of the concentration-response curve were calculated by the probit method. The no observed effect concentration is the highest tested concentration at which there was no toxicant-related mortality or sublethal effect.

Sublethal observations / clinical signs:

Measured concentrations of the Test Substance during the toxicity test with the fathead minnow, Pimephales promelas.

Nominal Concentration of Test Substance (mg a.i./L)	Measured Concentration of Test Substance (mg a.i./L)
	0 Hour	96 Hours	Mean	% Recovery
Test Media Samples
Control	ND	ND	ND	---
65	65	65	65	100
110	110	110	110	100
180	180	200	190	106
300	310	320	310	107
500	500	510	510	102
Laboratory Control Sample
180	180	180	180	100
Matrix Spike Sample
180	--	180	180	100
	--	170
Blank
0	ND	ND	ND	---

ND = none detected at or above the limit of quantitation (0.095 mg a.i./L).

Survival and sublethal effect data from the toxicity test with the Test Substance and the fathead minnow, Pimephales promelas.

Mean Measured Conc. of Test Substance (mg a.i./L)	R	Number Alive					Number Affected^1
		0 hr	24 hr	48 hr	72 hr	96 hr	0 hr	24 hr	48 hr	72 hr	96 hr
Control	1	10	10	10	10	10	0	0	0	0	0
	2	10	10	10	10	10	0	0	0	0	0
65	1	10	10	10	10	10	0	0	0	0	0
	2	10	10	10	10	10	0	0	0	0	0
110	1	10	10	10	10	10	0	0	0	0	0
	2	10	10	9	9	8	0	0	0	0	0
190	1	10	10	6	4	2	0	0	0	0	0
	2	10	8	5	3	2	0	0	0	0	1
310	1	10	7	2	1	1	0	0	0	0	0
	2	10	5	2	1	1	0	0	0	0	0
510	1	10	1	1	1	0	0	1	1	0	--
	2	10	0	0	0	0	0	--	--	--	--

R:  Replicate

¹ Affected fish were lethargic

Validity criteria fulfilled:

not specified

Conclusions:

Under the conditions of this study, exposure of fathead minnows to the test material resulted in a 96 hour LC50 of 160 mg/L with a 95 % confidence interval of 140 to 190 mg/L. The 96 hour NOEC was 110 mg/L test material (this concentration allowed 90 % survival with no sublethal effects).

Executive summary:

The acute toxicity of the test material to fathead minnows over 96 hours was assessed according to OECD 203, under GLP conditions.  

The test was performed under static conditions with a control and five concentrations of test substance at a temperature of 22 ± 1 °C.  The dilution water was deionized water was adjusted to a hardness of 40 to 48 mg/L as CaCO3.  Nominal concentrations of the test material were: 0 mg/L (control), 65, 110, 180, 300, and 500 mg/L.  Mean measured concentrations were: ND (not detected at or above the limit of quantitation of 0.095 mg/L; control), 65, 110, 190, 310, and 510 mg/L.  No insoluble material was observed at any concentration during the definitive toxicity test.   Mean measured concentrations were used for all toxicity determinations.

Fathead minnows used in the test were acclimated to test conditions for more than 14 days.  All test organisms were in good condition at the beginning of the study. 

Under the conditions of this study, exposure of fathead minnows to the test material resulted in a 96 hour LC50 of 160 mg/L with a 95 % confidence interval of 140 to 190 mg/L. The 96 hour NOEC was 110 mg/L test material (this concentration allowed 90 % survival with no sublethal effects).

Description of key information

Ward, Wyskiel, Boeri (2003)

Under the conditions of this study, exposure of fathead minnows to the test material resulted in a 96 hour LC50 of 160 mg/L with a 95 % confidence interval of 140 to 190 mg/L. The 96 hour NOEC was 110 mg/L test material (this concentration allowed 90 % survival with no sublethal effects).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

160 mg/L

Additional information

Ward, Wyskiel, Boeri (2003)

The acute toxicity of the test material to fathead minnows over 96 hours was assessed according to OECD 203, 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 substance at a temperature of 22 ± 1 °C.  The dilution water was deionized water was adjusted to a hardness of 40 to 48 mg/L as CaCO3.  Nominal concentrations of the test material were: 0 mg/L (control), 65, 110, 180, 300, and 500 mg/L.  Mean measured concentrations were: ND (not detected at or above the limit of quantitation of 0.095 mg/L; control), 65, 110, 190, 310, and 510 mg/L.  No insoluble material was observed at any concentration during the definitive toxicity test.   Mean measured concentrations were used for all toxicity determinations.

Fathead minnows used in the test were acclimated to test conditions for more than 14 days.  All test organisms were in good condition at the beginning of the study. 

Under the conditions of this study, exposure of fathead minnows to the test material resulted in a 96 hour LC50 of 160 mg/L with a 95 % confidence interval of 140 to 190 mg/L. The 96 hour NOEC was 110 mg/L test material (this concentration allowed 90 % survival with no sublethal effects).