3-methyl-4-phenylbutan-2-ol

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:

Between 19 and 21 October 1987

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The information is used for read across to Muguesia.

Reason / purpose for cross-reference:

read-across: supporting information

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

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Stability of test concentrations were verified by chemical analysis at 0 and 48 hours

Vehicle:

no

Details on test solutions:

The test water was dechlorinated (with sodium thiosulphate) and aged laboratory tap water,' Total hardness =: 350 mq/l as CaC03' This value is slightly higher than the recommended range but is not considered to have had any significant effects on the results of this test.

Test organisms (species):

Daphnia magna

Details on test organisms:

Name: Daphnia magna (Straus).
Source: Laboratory cuIture oriqinating from a strain supplied by IRCHA, France.
Culture: At 20 ± 2°C in glass vessels containing two litres of dechlorinated and aged tap-water. Cultures were fed daily with mixture of fry fish food (Liquifry ®) and a suspension of mixed algae (predominantly Chlorella spp.). Culture conditions ensure that reproduction is by parthenogenesis.
Selection: Gravid adults were isolated 24 hours prior to initiation of the test. Young daphnids produced overnight were used for testing.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

Not reported

Test temperature:

21 ± 1°C.

pH:

Not reported

Dissolved oxygen:

Not reported

Salinity:

freshwater used.

Nominal and measured concentrations:

0.18, 0.32, 0.56, l.0, 1.8, 3.2, 5.6, 10 and 18 mg/l.

Details on test conditions:

Exposure Conditions

Test vessels: Glass jars each containing 200 ml test solution.

Experimental design: 9 test concentrations plus 1 control (including 100 µl/l auxiliary solvent), each in duplicate. 20 animals per test concentration.

Method of initiation: Daphnia were placed in the test solutions after addition of the test substance.

Loading: 20 ml test solution per organism.

Photoperiod: 16 h light 8 h dark

Temperature: 21 ± 1°C.

Aeration: None.

Test concentrations: 0.18, 0.32, 0.56, l.0, 1.8, 3.2, 5.6,10 and 18 mg/l.

Medium renewal: None

Duration of exposure: 48 hours.

Criteria of effect: Daphnia were considered to be immobilised if they were unable to swim for approximately 15 seconds after gentle agitation.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

8.7 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CL 7. 3 - 10 mg/l

Details on results:

Analysis* of the immobility data gave the following results:

Time (h) EC" (mq/1) 95% confidence limits (mg/l)
24 >18 -
48 8.7 7.3 - 10
"no-effect" level~ at 24 h = 5.6 mg/l
"no-effect" level~ at 48 h = 3.2 mg/l

~Immobilisation less than or equal to 10%

*Thompson, W.R. and Weil, C.S. (1952) Biometrics

The results of the analytical verification of the test concentrations showed to be between 88 and 101% of nominal at 0 hours and between 54 and 88% after 48 hours.

Validity criteria fulfilled:

yes

Conclusions:

The 48h-EC50 of Pamplefleur to Daphnia magna was 8.7 mg/L (95% CL 7.3-10 mg/L).

Executive summary:

The acute toxicity of Pamplefleur to Daphnia magna was assessed under static conditions in a GLP study according to OECD Guideline No. 202. Daphnia were exposed to test concentrations of 0.18, 0.32, 0.56, l.0, 1.8, 3.2, 5.6,10 and 18 mg/L. Verifications of the test concentrations showed a decline of 54 to 69% after 48 hours only in the 0.18 and 0.56 mg/L test concentrations. In the 1.8, 5.6 and 18.0 mg/L test concentrations 86 to 88% of the substance could be verified. The 48h-EC50 was 8.7 mg/L with a 95% confidence limit of 7.3 -10 mg/L.

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

Justification for type of information:

The executive summary of the aquatic toxicity is presented. This includes the information on algae. The full read across is presented in the Endpoint summary. The accompaning files are also attached there.
Executive summary: Muguesia has the same aquatic toxicity as Pamplefleur because both substances are very similar in structure. Structural similarities and differences: The target and the source chemicals both have a phenyl-butyl backbone and an alcohol functional group. The differences are that an additional methyl is present on the butyl chain of Pamplefleur, and while Muguesia is a secondary alcohol, Pamplefleur is a primary alcohol. Overall, Pamplefleur has one more carbon than Muguesia, resulting in a slightly higher molecular weight and hence log Kow.
Bioavailability: The source chemical and the target chemical have similar bioavailability based on the similarity in chemical structure and physico-chemical properties. The molecular weight of the target substance (Muguesia) is 164.25, whereas for the source (Pamplefleur) it is 178.75. They are both liquids. They have similar vapour pressures, 1.1 and 0.3 Pa. The water solubility of Muguesia (3300 mg/L) is somewhat higher possibly due to the one methyl group less. This, however did not result in a lower log Kow (3.1) compared to Pamplefleur (log Kow is 3.0). The calculated log Kows did show a higher log Kow for Pamplefleur (ECOSAR) as expected.
Mode of Action and the prediction of the aquatic toxicity information: Muguesia and Pamplefleur have the same Neutral organic Mode of Action (OECD Toolbox and Verhaar rules).
Uncertainty of the prediction: There is no remaining uncertainty in view of the reasoning above. It is not thought necessary to convert the values of Pamplefleur towards Muguesia in view of the minor differences in both molecular weight and log Kow.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

8.7 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CL 7. 3 - 10 mg/l

Validity criteria fulfilled:

yes

Conclusions:

For Muguesia the 48h EC50 (immobilisation) value for Daphnia magna is 8.7 mg/L, based on the read-across substance Pamplefleur.

Description of key information

Muguesia is concluded to have an 48h EC50 value of 8.7 mg/L, based on the result of the read across substance Pamplefleur. The value is based on measured concentrations. The acute toxicity of Pamplefleur to Daphnia magna was assessed under static conditions in a GLP study according to OECD Guideline No. 202. Daphnia were exposed to test concentrations of 0.18, 0.32, 0.56, l.0, 1.8, 3.2, 5.6, 10 and 18 mg/L. Verifications of the test concentrations showed a decline of 54 to 69% after 48 hours only in the 0.18 and 0.56 mg/L test concentrations. In the 1.8, 5.6 and 18.0 mg/L test concentrations 86 to 88% of the substance could be verified. The 48h-EC50 was 8.7 mg/L with a 95% confidence limit of 7.3 -10 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

8.7 mg/L