Reaction products of 1,4-Benzenedimethanol and 1-naphthol

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:

06 May 2013 to 08 May 2013

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)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: The Japanese Ministry of Economy Trade and Industry (METI), Ministry of Health,Labour and Welfare (MHLW) and Ministry of the Environment (MOE).

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: JMAFF 2-7-2-1 The guidelines related to the study reports for the registrationapplication of pesticide (Ref. No. 12-Nousan-8147 on 24 November 2000 & Ref.No.13-Seisan-3986 on 10 October 2001).

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

No further details specified in the study report

Analytical monitoring:

yes

Remarks:

HPLC-UV analysis

Details on sampling:

Analytical measurement was performed at the applied test concentration level daily in the case of old and fresh media where was possible, and at the control at the start and at the end of the test. At each occasion, three replicate samples were taken from the test solutions and one sample from the control solution.
The samples were analysed by HPLC-UV.

Vehicle:

no

Details on test solutions:

Because the test item is very poorly soluble in water, a test solution was prepared using a saturated solution method according to the Guidance Document on Aquatic Toxicity Testing of Difficult Substances and Mixtures, OECD No. 23. A supersaturated test item stock solution (nominally 100 mg/L) was prepared by dispersing/dissolving the amount of test item into the test medium (ISO medium) two days before the start of the study. This solution was shaken for about 24 hours at approximately 30°C and then was equilibrated for about 24 hours at the test temperature. The non-dissolved test material was removed by filtration through a fine (0.22 μm) filter to give the 100 % v/v saturated solution.
As limit test was carried out, further dilution of stock solution was not performed.

Untreated Control
The dilution water (ISO medium) was used without addition of the test item.

Reference Control
For the evaluation of the quality of the Daphnia clone and the experimental conditions, Potassium dichromate is tested at least twice a year to demonstrate satisfactory test conditions.
The date of the last study (Study Code: 13/019-023DA) with reference item Potassium dichromate (batch no.: 0769128) is: 07-08 February 2013.
The 24h EC50: 0.89 mg/L, (95 % confidence limits: 0.72 – 1.02 mg/L)

Dilution Water
Reconstituted water (ISO medium, according to OECD 202) was used as dilution water for both the range finding and definitive tests. The same composition of reconstituted water was used for the tests and for breeding the test animals.

Test organisms (species):

Daphnia magna

Details on test organisms:

Species and strain: Daphnia magna
Source: National Institute of Public Health ,1097 Budapest Gyáli u. 2-6. Hungary
Breeding: The Daphnia are bred in Ecotoxicological Laboratory of CiToxLAB Hungary Ltd.
The health of the stock animals is continuously monitored by visual daily checking. Abnormal behavior or significant decrease of population is recorded.
Justification of strain: Daphnia magna is the standard species of the acute immobilisation test.
Number of animals: There were 20 animals in test group and control group respectively, divided into 4 replicates (5 animals/replicate).
Age of the animals: They were less than 24 h old at the beginning of the test
Acclimatization: There was no acclimatization because the water used was similar to the culture water.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Remarks on exposure duration:

Carried out in accordance to guideline specifications.

Post exposure observation period:

Not specified

Hardness:

The reconstituted water (ISO medium) had an approximate theoretical total hardness of 249 mg/L (as CaCO3).

Test temperature:

The test temperature was in the range of 20.3 – 20.4°C measured in the test vessels.
The additionally measured temperature in the climate chamber was between 20.0 and 20.6°C.

pH:

The pH of the test solution was not adjusted and not varied by more than 1.5 units in any one test. The pH was measured in each test vessel daily in the case of old and fresh media where was possible and was in the range of 7.76 – 8.03.

Dissolved oxygen:

The dissolved oxygen concentration was measured in each test vessel daily in the case of old and fresh media where was possible and was in the range of 7.8 – 8.1 mg/L.

Salinity:

Not specified

Conductivity:

Not specified

Nominal and measured concentrations:

Because a significant toxic response was not observed during the preliminary concentration range-finding test, only one test concentration at the solubility level of the test item in the test medium (100 % v/v saturated solution) and one control group were tested in a limit test.

Details on test conditions:

DESCRIPTION OF THE TEST PROCEDURE

The test duration was 48 hours. Twenty animals, divided into four groups (glass beaker) of five animals each (at least 5 mL test solution/animal) were used at the test concentration and for the control in a semi-static system. The animals were not fed during the test.
The choice of the test concentration was done on the basis of the results of a preliminary range-finding test.

Preliminary Range-Finding Test
A concentration range-finding test was conducted to determine the approximate toxicity of the test item so that appropriate test concentrations can be selected for use in the definitive test. Ten daphnids (divided into two replicates) in each test concentration and control were exposed for 48 hours under semi-static conditions.
During the formulation procedure the test solutions were prepared by the similar method described above except for test solutions of 1 % v/v saturated solution and 0.1 % v/v saturated solution. These solutions were prepared by appropriate dilution of test solutions of 10 % v/v saturated solution and 1 % v/v saturated solution respectively.

OBSERVATIONS
The immobility or mortality of the daphnids was determined by visual observation 24 and 48 hours after the start of the test. Those animals not able to swim within 15 seconds after gentle agitation of the test beaker are considered to be immobile.
The number of immobilised animals and the percentage of immobility were determined at 24 and 48 hours.
The water temperature, oxygen concentrations and pH of the control and the test solutions were measured at the start and at the end of each renewal period where it was possible.

Reference substance (positive control):

no

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

> 100 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

> 100 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Details on results:

There were no immobilized animal in the control group and the dissolved oxygen concentration at the end of the test in control and test vessels was more than 3 mg/L. All validity criteria were within acceptable limits and therefore the study can be considered as valid.
The number of immobilised animals and the percentage of immobility were determined at the 24th and 48th hour. In addition to immobility, no abnormal behaviour or appearance of test animals was detected.

Results with reference substance (positive control):

Not specified

Reported statistics and error estimates:

No statistical analysis was performed because of the lack of toxic effects.
The EC50, NOEC, LOEC and EC100 values were determined directly from the raw data.

Results of the Preliminary Range-Finding Test

% v/v saturated solution	Untreated control	0.1	1	10	100
Number of treated / immobilised animals	10 / 0	10 / 0	10 / 0	10 / 0	10 / 0

Number and percentage of immobilised animals

Test group	Number of treated animals	Number of immobilised animals
		24 hours		48 hours
		Number	Percent	Number	Percent
Control	20	0	0	0	0
100% v/v saturated solution	20	0	0	0	0

 

Temperature measured in the test vessels (°C)

Test Group	Replicate	Measuring
		0 h	24 h Old media	24 h Fresh media	48 h
Control	1	20.4	20.3	20.4	20.4
	2	20.4	20.3	20.4	20.4
	3	20.4	20.3	20.4	20.4
	4	20.4	20.3	20.4	20.4
100% v/v saturated solution	1	20.4	20.3	20.4	20.4
	2	20.4	20.3	20.4	20.4
	3	20.4	20.3	20.4	20.4
	4	20.4	20.3	20.4	20.4

Dissolved oxygen concentration measured in the test vessels (mg/L)

Test Group	Replicate	Measuring
		0 h	24 h Old media	24 h Fresh media	48 h
Control	1	7.9	7.9	8.0	8.0
	2	7.9	7.8	8.0	8.0
	3	7.9	7.8	8.0	7.9
	4	7.9	7.8	8.0	8.0
100% v/v saturated solution	1	8.0	8.1	8.0	8.0
	2	8.0	8.1	8.0	7.8
	3	8.0	8.1	8.0	7.9
	4	8.0	8.1	8.0	8.0

pH measured in the test vessels

Test Group	Replicate	Measuring
		0 h	24 h Old media	24 h Fresh media	48 h
Control	1	8.03	7.86	8.01	7.77
	2	8.03	7.87	8.01	7.80
	3	8.03	7.85	8.01	7.79
	4	8.03	7.87	8.01	7.76
100% v/v saturated solution	1	7.99	7.84	8.00	7.89
	2	7.99	7.85	8.00	7.92
	3	7.99	7.90	8.00	7.91
	4	7.99	7.83	8.00	7.88

 

Immobilisation of the test animals

Test Group	Replicate	Number of treated animals	Number of immobilised animals
			24 h	48 h
Control	1	5	0	0
	2	5	0	0
	3	5	0	0
	4	5	0	0
100% v/v saturated solution	1	5	0	0
	2	5	0	0
	3	5	0	0
	4	5	0	0

 

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of this Daphnia magna acute immobilisation study the observed endpoints for the effect of SN-475N were the followings:

The 24h and 48h EC50 value: > 100 % v/v saturated solution
The 48h NOEC: 100 % v/v saturated solution
The 48h LOEC: > 100 % v/v saturated solution
The 48h EC100 value: > 100 % v/v saturated solution

Based on the results of this study, the test item SN-475N had no toxic effect at saturation on Daphnia; the EC50 results and the LOEC are higher than the solubility level of the test item in the test medium.

Executive summary:

Acute toxicity of SN-475N onDaphnia magnawas assessed in an Acute immobilisation test, over an exposure period of 48 hours in a semi-static test system.

Toxic effects were not observed during the preliminary concentration range-finding test therefore a limit test was performed in the main experiment using only one test concentration at the limit of solubility of the test item in the test medium (100 % v/v saturated solution) and one control group.

Test concentration was analytically determined at the start and at the end of the experiment, however the measured concentration was below the Limit of Quantification (LOQ = 2.0 mg/L) daily during the test period, after increasing the concentration by a factor of 25 by freeze-drying method. Therefore it can be stated that the solubility level of the test item is lower than 2.0/25=0.08 mg/L.

Twenty animals, divided into four groups (glass beaker) of five animals each were used at the test concentration and for the control.

All validity criteria were met during this study.

Under the conditions of thisDaphnia magnaacute immobilisation study the observed endpoints for the effect of SN-475N were the followings:

The 24h and 48h EC50value: > 100 % v/v saturated solution

The 48h NOEC: 100 % v/v saturated solution

The 48h LOEC: > 100 % v/v saturated solution

The 48h EC100value: > 100 % v/v saturated solution

Based on the results of this study, the test item SN-475Nhadno toxic effect at saturation on Daphnia; the EC50results and the LOEC are higher than the solubility level of the test item in the test medium.

Description of key information

Acute toxicity of SN-475N on Daphnia magnawas assessed in an Acute immobilisation test, over an exposure period of 48 hours in a semi-static test system.

Based on the results of this study, the test item SN-475Nhadno toxic effect at saturation on Daphnia; the EC50 results and the LOEC are higher than the solubility level of the test item in the test medium.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

Toxic effects were not observed during the preliminary concentration range-finding test therefore a limit test was performed in the main experiment using only one test concentration at the limit of solubility of the test item in the test medium (100 % v/v saturated solution) and one control group.

Under the conditions of thisDaphnia magnaacute immobilisation study the observed endpoints for the effect of SN-475N were the followings:

The 24h and 48h EC50value: > 100 % v/v saturated solution

The 48h NOEC: 100 % v/v saturated solution

The 48h LOEC: > 100 % v/v saturated solution

The 48h EC100value: > 100 % v/v saturated solution