2-methoxy-4-(methoxymethyl)phenol

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

7 - 17 October 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Reliability 1 is assigned because the study was conducted according to OECD TG 202 in compliance with GLP.

Reason / purpose for cross-reference:

other: Information used for read across

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

The test concentrations of the test item were verified by HPLC analysis with UV/Vis detection.

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: Straus
- Source: cultured in-house, obtained from a strain originating from the University of Sheffield in UK
- Age at study initiation: 6-24 hours old
- They were not first brood progeny.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

The numbers of mobile, immobile and floating Daphnia were counted approximately 24 and 48 hours after the start of the study.

Hardness:

250 mg/l

Test temperature:

19 - 21°C

pH:

7.8 - 7.9

Dissolved oxygen:

> 8.5 mg O2/l

Nominal and measured concentrations:

Nominal test concentrations: 4.6, 10, 22, 46 and 100 mg/I.
Measured test concentrations (at the day 0): 4.79, 10.2, 21.1, 44.3 and 90.5 mg/l.
Measured test concentrations (at the day 2): 4.65, 10.2, 21.8, 42.6 and 88.6 mg/l.
Measured test concentrations (means): 4.72, 10.2, 21.4, 43.4 and 89.5 mg/I.

Details on test conditions:

TEST SYSTEM
- At each concentration and for the control, 20 daphnids were used, divided into two replicates of ten daphnids each. The daphnids were randomly distributed to the test vessels at initiation of the test. The loading rate was lower than one daphnia per 2 ml test solution.
- The test was performed in 100 ml glass beakers filled with 50 ml test medium.
- Cultures were maintained at 19 - 21 °C under a photoperiod of 16 hours light : 8 hours dark (light intensity: 500 - 685 Lux) and without supplementary feeding during the 48 hour exposure period.
- The temperature in each vessel, the pH and dissolved oxygen levels were recorded at the start and at the end of the study. The appearance of the test media was visually recorded at the start of the test and after 24 and 48 h.

EFFECT PARAMETERS MEASURED: Daphnia were considered to be immobilised if they were unable to swim for approximately 15 seconds after gentle agitation of the test vessel.

Reference substance (positive control):

yes

Remarks:

potassium dichromate, tested at least once a year

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

23 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL 17 and 30 mg/L

Details on results:

Measured concentrations in the analyzed test media from the start and the end of the test ranged between 89-104 % of the nominal values. The test item was stable in the test media during the test period of 48 h. Therefore, the results are based on the nominal concentrations.
Individual pH, temperature and dissolved oxygen values remained within acceptable limits throughout the duration of the study.

Reported statistics and error estimates:

The 48-hour EC50 and the 95% confidence limits were calculated by Probit Analysis.

Cumulative immobilisation data for Daphnia magna exposed for 48 hours to the test substance:

Nominal test item concentration (mg/l)	No. of daphnids tested	Immobilized daphnids after 24 hours – no.	Immobilized daphnids after 24 hours – %	Immobilized daphnids after 48 hours – no.	Immobilized daphnids after 48 hours – %
0	20	0	0	0	0
4.6	20	0	0	0	0
10	20	0	0	4	20
22	20	0	0	11	55
46	20	2	10	16	80
100	20	4	20	18	90

Validity criteria fulfilled:

yes

Conclusions:

The 48 h-EC50 is 23 mg/l.

Executive summary:

An acute Daphnia study was performed in accordance with OECD TG 202 using static exposure. Groups of twenty Daphnia (less than 24 hours old) were exposed for 48 hours to five concentrations of the substance dispersed in test water. The test solution at the nominal concentration of 100 mg/l was prepared and was stirred intensely for 10 min at RT. Then the other test solutions were prepared by diluting this solution. The nominal concentrations ranged from 4.6 to 100 mg/l. Measured concentrations in the analyzed test media from the start and the end of the test ranged between 89-104 % of the nominal values. The test item was stable in the test media during the test period of 48 h. Therefore, the results are based on the nominal concentrations. The EC50 after 48h was 23 mg/I.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: read across was applied

Justification for type of information:

Read across from Methyl diantilis was applied. The respective read-across document can be found in the endpoint summary. The read-across document is also attached in the endpoint summary.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

23 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL 17 and 30 mg/l

Description of key information

The EC50 after 48h was 23 mg/I, based on read across from Methyl diantilis.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

23 mg/L

Additional information

For Vaniwhite, read across from Methyl diantilis was applied. Read across justification is added in the endpoint summary of Aquatic toxicity because also the algae toxicity is presented there. Below the experimental results for Methyl diantilis are presented.

An acute Daphnia study was performed in accordance with OECD TG 202 using static exposure. Groups of twenty Daphnia (less than 24 hours old) were exposed for 48 hours to five concentrations of the substance dispersed in test water. The test solution at the nominal concentration of 100 mg/l was prepared and was stirred intensely for 10 min at RT. Then the other test solutions were prepared by diluting this solution. The nominal concentrations ranged from 4.6 to 100 mg/l. Measured concentrations in the analyzed test media from the start and the end of the test ranged between 89-104 % of the nominal values. The test item was stable in the test media during the test period of 48 h. Therefore, the results are based on the nominal concentrations. The EC50 after 48h was 23 mg/I.