Reaction products of 1H-Imidazole-1-ethanol, 4,5-dihydro-, 2-(C7 odd-numbered alkyl) derivs. and sodium hydroxide and chloroacetic acid

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

25 Jun 2018 - 17 Aug 2018

Justification for type of information:

The rationale to read across the data is attached in Section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

4 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: Test substance corrected for water content (specified in report as "solids")

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence interval: 3.3 - 4.8 mg solids/L

Details on results:

- No mortality or other effects were observed in the control and the three lowest concentrations tested during the exposure period. All fish exposed to the highest concentration were found dead after the first 24 hours of exposure. Four and six of the fish exposed to 5.1 mg solids/L were found dead after 72 and 96 hour of exposure, respectively.
- Fish exposed to 5.1 mg solids/L were observed to be red coloured from 48 hour of exposure.
- Concentrations measured in freshly prepared solutions were at the level of nominal concentrations (99 – 115%). In spent solutions, measured concentrations were at 95-142% of nominal concentrations. The reason behind the observed increase of concentrations is unknown.
- All environmental parameters remained within the limits prescribed by the study plan throughout the test.

Results with reference substance (positive control):

The 96h-LC50 for carp exposed to PCP was 0.15 mg/L (95 % confidence interval between 0.10 and 0.22 mg/L).
The range of the 96h-LC50 for carp is generally between 0.10 and 0.46 mg/L based on historical data of reference tests performed approximately every 3 months from April 1988 until the end of 2000, and annually since then. Hence, the sensitivity of carp originating from the present batch for PCP falls within the range of sensitivities generally observed during the past years.

Reported statistics and error estimates:

The 96h-LC50 value was calculated using the Spearman-Karber procedure (without trim). ToxRat Professional v 3.2.1 (ToxRat Solutions® GmbH, Germany) was used to perform the analyses.

Sublethal observations / clinical signs:

Table 1: Average Exposure Concentration Versus Nominal Concentration

Nominal concentration  (mg solids/L)	Measured concentrations (mg solids/L)				Average conc. (mg solids/L)
	t=0h (new)	t=24h (old)	t=72h (new)	t=96h (old)
0.46	0.52	0.56	0.46	0.65	0.54
1.0	1.0	0.95	1.1	1.2	1.1
2.2	2.3	2.5	2.4	2.8	2.5
4.6	4.7	5.2	5.3	5.4	5.1
10	10	12	n.a.	n.a.	11

n.a. – not applicable, no surviving fish were present in this concentration

Table 2: Incidence of Mortality and Total Mortality During the Final Test

Average exposure conc. (mg solids/L)	Initial Number of fish	Cumulative mortality					Total Mortality (%)
		3h	24h	48h	72h	96h
Control	7	0	0	0	0	0	0
0.54	7	0	0	0	0	0	0
1.1	7	0	0	0	0	0	0
2.5	7	0	0	0	0	0	0
5.1	7	0	0	0*	4*	6*	86
11	7	0	7	7	7	7	100

*Fish were observed to be red coloured compared to the control.

Validity criteria fulfilled:

yes

Remarks:

See 'Overall remarks'

Conclusions:

The 96h-LC50 was 4.0 mg solids/L based on average exposure concentrations (95% confidence interval between 3.3 and 4.8 mg solids/L). This result is read across to Amphoacetates C8.

Executive summary:

In a study performed in accordance with OECD 203 (1992) and according to GLP principles, the acute toxicity of the test substance to Cyprinus carpio was investigated. The test item consisted of 39.15% solids in water and was completely soluble in test medium at the concentrations tested. A correction factor of 2.554 was used and concentrations/doses are expressed as mg solids/L.

In a semi-static test, carp were exposed for 96 hours to an untreated control and nominal test concentrations of 0.46, 1.0, 2.2, 4.6 and 10 mg solids/L. Measured concentrations were at the level of nominal concentrations (99 -115%) in freshly prepared medium and at 95 - 142% of nominal in spent solutions. Therefore, the average exposure concentrations were calculated to be 0.54, 1.1, 2.5, 5.1 and 11 mg solids/L. No mortality or other effects were observed in the control and at the three lowest concentrations tested during the exposure period. All fish exposed to the highest concentration were found dead after the first 24 hours of exposure. Six of the 7 fish exposed to 5.1 mg solids/L were found dead after 96 hours of exposure. The 96h-LC50 was calculated to be 4.0 mg solids/L based on average exposure concentrations (95% confidence interval: 3.3 - 4.8 mg solids/L). The test met all validity criteria and is considered to be reliable without restriction. This result is read across to Amphoacetates C8.

Description of key information

In a study performed in accordance with OECD 203 (1992) and according to GLP principles, the acute toxicity of the analogue Amphoacetates C8 -C18 to Cyprinus carpio was investigated. The test item consisted of 39.15% solids in water and was completely soluble in test medium at the concentrations tested. A correction factor of 2.554 was used and concentrations/doses are expressed as mg solids/L.

In a semi-static test, carp were exposed for 96 hours to an untreated control and nominal test concentrations of 0.46, 1.0, 2.2, 4.6 and 10 mg solids/L. Measured concentrations were at the level of nominal concentrations (99 -115%) in freshly prepared medium and at 95 - 142% of nominal in spent solutions. Therefore, the average exposure concentrations were calculated to be 0.54, 1.1, 2.5, 5.1 and 11 mg solids/L.

No mortality or other effects were observed in the control and at the three lowest concentrations tested during the exposure period. All fish exposed to the highest concentration were found dead after the first 24 hours of exposure. Six of the 7 fish exposed to 5.1 mg solids/L were found dead after 96 hours of exposure. The 96h-LC50 was calculated to be 4.0 mg solids/L based on average exposure concentrations (95% confidence interval: 3.3 - 4.8 mg solids/L). The test met all validity criteria and is considered to be reliable without restriction. This result is read across to Amphoacetates C8.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

4 mg/L

Additional information

96h-LC50: 4.0 mg/L, based on analytically confirmed test substance corrected for water content (and specified in the report as "solids").