3-methoxy-3-methylbutan-1-ol

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:

2001-12-05 to 2002-03-26

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:

yes

Remarks:

The Test Guideline includes Part I - the 24h EC 50 acute immobilisation test and Part II - the reproduction test (at least 14 days). Accoding to this study the acute immobilisation test was conducted with a duration of 48 h, part II was not conducted.

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Test chemical was refrigerated. 500 mg test chemical was diluted in 500 mL dilution water and which was used as 1000 mg/L test solution.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia Magna
-Strain: had been reproduced for 5 years.
- Source: National Institute for Environmental Studies, Ministry of Environment, .
- Age at study initiation (mean and range, SD): Juveniles less than 24 hours old
- Method of breeding: Subculture (maximum rearing period: four weeks, frequency of water exchange: at least twice a week)
- Feeding during test: no feeding


ACCLIMATION
- Acclimation period: December 19, 2001 to January 15, 2002, Parental daphnids were acclimated for 27 days on test condition before testing
- Acclimation conditions (same as test or not): same; water temperature 20+-1°C, 16-8 hours room light-dark photocycle
- Type and amount of food: Chlorella vulgaris, 0.15-0.2 mgC (organic carbon)/organism/day
- Health during acclimation (any mortality observed): death rate of parents was 5% or less in two weeks before exposure, no production of resting eggs or males was observed

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

no data, artificially prepared water Elendt M4

Test temperature:

20.4 - 20.6°C +/- 1°C

pH:

8.1

Dissolved oxygen:

8 - 8.2 mg/L

Salinity:

no data, artificially prepared water Elendt M4

Nominal and measured concentrations:

measured concentration was within +/- 20% of the nominal value

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL glass vessel with screw tubes
- Material, size, headspace, fill volume: 100 mL/container
- Aeration: not described
- No. of organisms per vessel: 5 fleas /container
- No. of vessels per concentration (replicates): 4 containers /concentration

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M4

OTHER TEST CONDITIONS
- Adjustment of pH: no adjustment,but ph measurement
- Photoperiod: 16-8 hours light dark photocycle
- Light intensity: room light

TEST CONCENTRATIONS
- Justification for using less concentrations than requested by guideline: Based on the results of the preliminary test, the concentraion of 1000 mg/L and control were set.
- Test concentrations: 1000 mg/L test solution

Reference substance (positive control):

yes

Remarks:

48 hour median immobilization concentration (EiC50) by potassium dichromate, special grade chemical was 0.67 mg/L (EiC50 value at our site is 0.49 - 1. 1 mg/L, n = 5, since October 1999)

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Infrared absorption spectrum of the refrigerated test chemical was detected at the start and the end of the test, and both spectrums are not contradictory to each other.

The immobility of the control group under 48 -hour exposure was 0% and the rate of the fleas that surfaced was 0% and it fulfilled the conditions for establishing the test.

Mortality or Immobility: No test organism was Immobilized
at any concentration.
-----------------------------------------------------------
       Cumulative Number of Dead or Immobilized
Daphnids
Nominal         (Percent Mortality or Immobility)
Conc.      
-----------------------------------------------------------
mg/L                  24 Hour         48 Hour
-----------------------------------------------------------
Control               0 ( 0 )         0 ( 0 )
1,000                 0 ( 0 )         0 ( 0 )
-----------------------------------------------------------

Validity criteria fulfilled:

not specified

Conclusions:

MMB was observed to cause no immobilizing effects on daphnia magna after 48h at a concentration of 1000 mg/L.

Executive summary:

The test on acute toxicity of 3-methoxy-3-methyl-1-butanol towards invertebrates was performed according to OECD 202. The water flea (Daphnia magna) juveniles, within 24 hours after birth, were used as test organisms. The study was conducted under static conditions over 48h. Each of 20 test organisms was exposed to the test concentration of 1000 mg/L and the control. The concentration of the test substance was within +/- 20% of the nominal value, and each effect concentration was calculated, adopting the nominal value. MMB was found to cause no toxicity on daphnia magna after 24h and after 48h at a concentration of 1000 mg/L . The EC50 24h was > 1000 mg/L and the EC50 48 h was > 1000 mg/L.

Description of key information

48h-EC50 > 1000 mg/L

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1 000 mg/L