Diethyl bis(2-hydroxyethyl)aminomethylphosphonate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1990

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

No analytical monitoring was performed in this study. As the analytical confirmation of the nominal concentrations is a validity criteria of the OECD test guideline 203, this study is not reliable and can be used only in a weight of evidence approach.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

No analytical monitoring.

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Details on sampling:

Observations of the fish were made 0.25, 2, 4 and 24 hours after the start of the test and thereafter every 24 hours.

Vehicle:

no

Details on test solutions:

A preliminary trial indicated that that the test material was soluble in water up to a concentration of 1 g/L. Test dilutions were therefore individually prepared by the direct addition of test item to dilution water. The following nominal exposure concentrations were employed: 1, 1.8, 3.2, 5.6 and 10 g/L.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

1. TEST ORGANISM:
- Supplier: Hauxton Fishery Services, Cambridge
- Origin: reared at Zeals Trout Farm, Gillingham, Dorset from eggs imported from Tasmania; hatched late September 1989
- Transport conditions: hardness of the water used to transport the fry was 318 mg/L (CaC03)
- Holding conditions: At the laboratory in an aerated supply of dilution water under flow-through conditions
- Monitoring water quality during the 14 day holding period: temperatures: 11.8 to 14.8°C; pH-values: 7.14 to 7.78; dissolved oxygen (DO): 92 to 100% air
saturation value (ASV); water hardness: 218 to 228 mg/L (CaC03)
- Feeding during the holding period: daily feeding; proprietary trout pellets (BP Nutrition Ltd., Mainstream Trout Fry 02); an amount equivalent to between 1 and 4% of the total wet-weight of the fish; last fed 22 hours before the start of the definitive test
- Mortality during the 14-day period: less than 2%
- The mean wet-weight of the fish: 0.93 g, based on a sample of ten fish taken at random from the holding tank on 11 December 1989

2. TEST ENVIRONMENT:
- Temperature: 15 +/- 1 °C, carried out in a temperature-controlled area
- Photoperiod: 16 hours light, supplied by overhead fluorescent tubes, and eight hours darkness; dawn and dusk were simulated by periods of subdued lighting at the beginning and end of each light phase
- Dilution water: blended tap water, filtered through activated carbon to remove chlorine, with tap water, which had been softened and treated by reverse
osmosis, to achieve hardness in the range 200-250 mg/L as CaC03; equilibrated to the test temperature and gently aerated before being supplied to the holding and test areas

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

214-220 mg/L as CaC03 (concerning the highest test concentration of 10.000 mg/L)

Test temperature:

14.3-15.0 °C (concerning the highest test concentration of 10.000 mg/L)

pH:

7.57-8.25 (concerning the highest test concentration of 10.000 mg/L)

Dissolved oxygen:

47-98 % ASV (concerning the highest test concentration of 10.000 mg/L)

Salinity:

n.a.

Conductivity:

No data

Nominal and measured concentrations:

6 test concentrations (n): 1, 1.8, 3.2, 5.6 and 10 g/L

Details on test conditions:

APPARATUS:
- The test vessels were all-glass aquaria, with a total capacity of 15 litres
- Aeration of the contents of each vessel was achieved using a Pasteur pipette connected to an oil-free supply of compressed air

PREPARATION OF DILUTIONS OF THE TEST MATERIAL:
- A preliminary trial indicated that that the test material was soluble in water up to a concentration of 1g/L
- Test dilutions were therefore individually prepared by the direct addition of the test item to dilution water.

TEST DESIGN

1. Preliminary test:
- Test concentrations: 10, 100, 1000 and 10000 mg/L
- The methods in this test were essentially similar to those employed in the definitive test (see below)

2. Definitive test:
- Test concentrations: 1, 1.8, 3.2, 5.6 and 10 g/L or and the dilution water alone
- Number of test organism: 5 fish/per group
- Replicate: 2
- Test vessel: 10 litre vessel
- Volume of test water: 7 litres
- Aeration: Continuous
- pH: not adjusted prior to the start of the test nor controlled during the test
- Feeding: None
- Observations: made at 0.25, 2, 4, 24, 48, 72 and 96 hours after the start of the test

3. Water quality analysis:
- The temperature, pH and concentration of dissolved oxygen of the contents of all vessel was measured at the start of the tests and thereafter each day either immediately before or following the observations of fish behaviour
- The total hardness of the dilution water control and selected test dilutions were determined at the start and end of the tests

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

1 800 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

See tables in "Any other information on results incl. tables".

Mortalities were limited to two of the five fish exposed to a nominal test concentration of 10 g/L in the preliminary test, and two deaths in the definitive study at a nominal 3.2 g/L. These latter two may have been caused by a fall in the dissolved oxygen level which was observed during the second 48 hours of the test. FYROL 6 is, however, not considered to be acutely toxic to fish when dispersed in water at levels up to 10 g/L, the highest nominal concentration used.

Dose-related signs of sublethal toxicity (increased ventilation rate and coughing, darkened pigmentation, loss of coordination and the occurrence of mucus with the faeces) were seen in fish exposed to the test substance at levels of 3.2 g/L and above. The no-observed-effect concentration was thus found to be 1.8 g/L.

Reported statistics and error estimates:

Since no dose-related mortality occurred during the study, LC50 values could not be calculated.

Sublethal observations / clinical signs:

Test environment and water quality in the definitive test:

At the start of the test, all test dilutions were clear, yellow-coloured solutions. The intensity of their colour increased with increasing concentration. By 72 hours test dilutions, except for that at 10 g/L, had become hazy, and their pH and concentrations of dissolved oxygen had declined. These changes were most marked at 1.8 and 3.2 g/L. By 96 hours, all dilutions were hazy and an odour was perceptible.

 

Table 1: Cumulative mortality in the definitive test

Observation Times	Control	Nominal test substance concentrations (mg/L)
		1000	1800	3200	5600	10000
15 minutes 2 hours 4 hours 24 hours 48 hours 72 hours 96 hours	0 0 0 0 0 0 0	0 0 0 0 0 0 0	0 0 0 0 0 0 0	0 0 0 0 0 0 2	0 0 0 0 0 0 0	0 0 0 0 0 0 0

 

Table 2: Water quality in the definitive test

Parameter	sampling interval	Control	Nominal test substance concentrations (mg/L)
			1000	1800	3200	5600	10000
Temperature, °C	Min Max	14.3 15.0	14.1 15.0	14.2 15.0	14.3 15.0	14.2 15.0	14.3 15.0
pH	0 hours 24 hours 48 hours 72 hours 96 hours	8.02 8.31 8.06 8.18 7.96	8.05 8.28 7.93 7.83 7.52	8.08 8.23 7.88 7.66 7.28	8.09 8.24 7.91 7.63 7.14	8.11 8.32 7.99 7.97 7.08	8.13 8.25 7.87 8.00 7.57
Dissolved Oxygen, % ASV	0 hours 24 hours 48 hours 72 hours 96 hours	100 98 95 91 95	100 92 88 73 62	99 89 88 65 38	98 89 89 44 33	98 91 93 73 37	98 92 90 82 47
Total hardness, mg/L as CaCO3	0 hours 96 hours	208 216	210 206	- -	- -	- -	214 220

Validity criteria fulfilled:

no

Remarks:

No analytical monitoring was performed. Therefore, it's not possible to confirm that the concentrations of the tested substance have been satisfactorily maintained.

Conclusions:

The acute toxicity of diethyl bis(2-hydroxyethyl)aminomethylphosphonate to fish was investigated in a static GLP study following OECD 203. The study reported of no effects after 96 hours of exposure. The no-observed effect concentration (NOEC) was 1800 mg/L relating to nominal concentrations. Since no dose-related mortality occurred during the study, LC50 values could not be calculated.

Executive summary:

The test was conducted in accordance with Procedure 203 of the Guidelines for the Testing of Chemicals of the OECD: 'Fish, Acute Toxicity' adopted 4 April 1984. The objective of this study was to determine the acute lethal toxicity to the rainbow trout, Salmo gairdneri.

In a preliminary test, groups of five fish were exposed to the dilution water alone, or to four nominal concentrations of test substance ranging from 10 to 10000 mg/L. The highest nominal concentration at which no mortality occurred was 1000 mg/L. The highest tested concentration (10000 mg/L) caused 40% mortality after 96 hours. In a similarly conducted definitive test, groups of ten fish were exposed to dilution water alone, or the following nominal concentrations of 1, 1.8, 3.2, 5.6 and 10 g/L. Test dilutions were individually prepared by the direct addition of FYROL 6 to water with a hardness of 206 -220 mg/L as CaCO3 at pH 7.08- 8.32 and with temperatures in the range 14.1 -15.0 °C. At the start of the test, dilutions of the test item were clear with a yellow colour, the intensity of which increased with concentration. During the second 48 hours of the test, they became hazy and an odour was perceptible. These changes in the appearance of the test dilutions were accompanied by a reduction in both their pH and dissolved oxygen levels. Observations of the fish were made 0.25, 2, 4 and 24 hours after the start of the test and thereafter every 24 hours. Dose-related signs of sublethal toxicity, including increased ventilation rate and coughing, darkened pigmentation, loss of coordination and the occurrence of mucus with the faeces, were seen in fish exposed to diethyl bis(2-hydroxyethyl)aminomethylphosphonate at levels of 3.2 g/L and above. In addition, two fish died at 3.2 g/L after exposure to diethyl bis(2-hydroxyethyl)aminomethylphosphonate for 96 hours. No deaths were seen at the higher test concentrations. The no-observed-effect concentration was thus found to be 1.8 g/L. 

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1990

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

No analytical monitoring was performed in this study. As the analytical confirmation of the nominal concentrations is a validity criteria of the OECD test guideline 203, this study is not reliable and can be used only in a weight of evidence approach.

Qualifier:

according to guideline

Guideline:

other: UBA test protocol: Letale Wirkung beim Zebrabaerbling Brachydanio rerio, (LC 0, LC 50, LC 100; 48 — 96H) Stand Mai 1984

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

No analytical monitoring

Principles of method if other than guideline:

Method: other: UBA-Verfahrensvorschlag "Letale Wirkung beim Zebrabaerbling Brachydanio rerio" (LC 0, LC 50, LC 100; 48-96 Stunden) (Mai 1984)

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM:
- Supplier: West Aquarium GmbH (Germany)
- Temperation: 20-24 °C
- Dissolved oxygen: 5 mg/L
- Medication: none
- Mortalities during acclimatization: < 5 %
- Keeping water: freshwater prepared after ISO: hardness: 13° dH, acidity: 0.1 +1- 0.02 mmol/l, Ca / Mg: 4:1, pH: 8.0 — 8.4, Oxygen: >= 90 % of saturation

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

13° dH

Test temperature:

The temperature varied between 20.3 – 22.4 °C (daily monitoring)

pH:

pH-values varied betweeen 7.0 – 8.1 (daily monitoring)

Dissolved oxygen:

Oxygen concentration varied between 1.1 – 8.7 mg/L (daily monitoring)
Two times, the oxygen concentrations in the test media were measured to be very low. An explanation was not given. Nevertheless, it was shown that this effect had no influence on the results. All fish showed no abnormalities and had survived.

Salinity:

no data

Nominal and measured concentrations:

10, 100, 1000, 3162 and 10000 mg/L (nominal)

Details on test conditions:

TEST SYSTEM:
- test vessel: glass aquarium, 5 l test media covered with glass plates
- Experimental design: 5 test concentrations plus 1 control, 10 animals per test concentration
- Method of initiation: animals were placed in prepared media
- method of administration: direct weighing
- photoperiod: 16 hours light, 8 hours dark
- temperature: 20 - 24 °C
- Medium renewal: none
- no feeding during exposure period
- test parameter: mortality (recorded daily)

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

See table 1 in "Any other information on results incl. tables".

Sublethal observations / clinical signs:

Table 1: Results

	Parameters	0h	24h	48h	72h	96h
Control	Temperature (°C) Abnormality	21.6	21.8	21.5	21.2	21.2
	Oxygen (mg/L)	7.2	7.3	7.7	7.8	7.7
	pH value	7.9	7.2	7.1	7.2	7.2
	Mortality*	0	0	0	0	0
	Abnormality**	0	0	0	0	0
10 mg/L	Temperature (°C) Abnormality	21.5	20.9	20.7	20.4	20.8
	Oxygen (mg/L)	8.5	7.7	7.2	7.8	7.5
	pH value	8.1	7.6	7.4	7.5	7.5
	Mortality*	0	0	0	0	0
	Abnormality**	0	0	0	0	0
100 mg/L	Temperature (°C) Abnormality	21.5	20.9	20.6	20.3	20.9
	Oxygen (mg/L)	8.7	7.7	6.7	7.8	7.3
	pH value	8.1	7.7	7.8	7.5	7.5
	Mortality*	0	0	0	0	0
	Abnormality**	0	0	0	0	0
1000 mg/L	Temperature (°C) Abnormality	21.5	21.0	20.8	20.5	20.9
	Oxygen (mg/L)	8.7	6.4	7.0	7.3	6.2
	pH value	7.8	8.0	7.5	7.4	7.4
	Mortality*	0	0	0	0	0
	Abnormality**	0	0	0	0	0
3162 mg/L	Temperature (°C) Abnormality	22.3	22.0	21.8	21.0	20.6
	Oxygen (mg/L)	7.0	6.8	3.9	6.4	6.9
	pH value	7.7	7.4	7.0	7.0	7.1
	Mortality*	0	0	0	0	0
	Abnormality**	0	0	0	0	0
10000 mg/L	Temperature (°C) Abnormality	22.4	22.0	21.8	20.9	20.7
	Oxygen (mg/L)	7.0	6.3	1.1	6.5	7.2
	pH value	7.6	7.5	7.2	7.3	7.2
	Mortality*	0	0	0	0	0
	Abnormality**	0	0	0	0	0

* Absolute value; Initial population = 10

** Absolute value; Fish with effects (inactive, lethargic swimming behaviour)

Validity criteria fulfilled:

no

Remarks:

No analytical monitoring was performed. Therefore, it's not possible to confirm that the concentrations of the tested substance have been satisfactorily maintained.

Conclusions:

After 96 hours no toxic effects was observed up to 10000 mg/L. The LC 0 is 10000 mg/L.

Executive summary:

In order to test acute toxicity to fish of the substance, Groups of ten fishes were exposed to 5 test concentration

( 10, 100, 1000, 3162 and 10000 mg/L, nominal concentration). Observations were made on the numbers of dead fish and the incidence of sub-lethal effects after 0, 24, 48, 72 and 96 hours of exposure. (Method: UBA test protocol: Letale Wirkung beim Zebrabaerbling Brachydanio rerio).

After 96 hours no toxic effects was observed up to 10000 mg/L. The LC 0 is 10000 mg/L.

Description of key information

The acute toxicity of diethyl bis(2-hydroxyethyl)aminomethylphosphonate to fish was investigated in a weight of evidence approach with two experimental studies, following OECD Test Guideline 203 or equivalent, on rainbow trout Salmo gairdneri and Danio rerio (Jenkins, 1990 and Ranz, 2014). Both studies were conducted under static conditions with five nominal tested concentrations, up to 10 000 mg/L. However, as no analytical monitoring was performed it's not possible to confirm that the tested concentrations have been satisfactorily maintained. Both studies reported no effects after 96 hours of exposure. Since no dose-related mortality occurred during the study, a real LC50 values could not be calculated. The 96h-LC50 value for both fish species is greater than 10 000 mg/L, based on nominal concentrations.

Additional information

Two experimental studies, guideline or equivalent, GLP or not, are available. No analytical monitoring was performed. As the analytical confirmation of the nominal concentrations is a validity criteria of the OECD TG 203, these studies are not reliable and can be used only in a weight of evidence approach.