3,7-dimethyloct-6-en-3-ol

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

09/05/2000-31/08/2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study according to international guideline (OECD Guideline 203) under GLP conditions, validity criteria considered to be met.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

2000

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

in darkness

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

yes

Remarks:

in darkness

Principles of method if other than guideline:

Not relevant

GLP compliance:

yes

Remarks:

Statement of compliance

Test material

Test material information

Constituent 1

Reference substance name:

3,7-dimethyloct-1-en-3-ol

EC Number:

242-358-2

EC Name:

3,7-dimethyloct-1-en-3-ol

Cas Number:

18479-49-7

Molecular formula:

C10H20O

IUPAC Name:

3,7-dimethyloct-6-en-3-ol

Details on test material:

- Name of test material (as cited in study report): Dihydrolinalool
- Physical state: Liquid
- Storage condition of test material: In refrigerator protected from light

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not relevant

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Nominal 5.6, 10, 18, 32 and 56 mg/l
- Sampling method: During the test samples were taken from 5.6, 18 and 56 mg/l and the blank-control for analysis. Since all fish died at the highest concentration before the end of the exposure period, samples were taken from the highest remaining concentration (32 mg/l). No samples were
taken at the start (0h) and before removal of the dead fish at 56 mg/l. Samples were taken at the start of the second renewal period (t=24h) from the
freshly prepared solution of 56 mg/l and of the respective 24h-old solution (t=48h), at the start of the third renewal period (t=48h) from the freshly prepared solutions of 5.6, 18 and 32 mg/l and the blank control and of the respective 24h-old solutions (t=72h) and at the start of the fourth
renewal period (t=72h) from the freshly prepared solutions of 5.6, 18 and 32 mg/l and the blank control. The volume of the samples was 10 ml from
the approximate centre of the test vessels, except for one samples pf 32 mg/l (20 ml).
- Sample storage conditions before analysis: Not applicable, samples were analysed on the day of sampling.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Preparation of test solutions started with a stock solution of 1000 mg/l. Magnetic stirring was sufficient to achieve complete dissolution of the test substance in the test medium. The lower concentrations tested were prepared by subsequent dilutions in test medium. Test solutions were renewed after 24 hours of exposure. The preparation of test solutions was performed in the dark as much as possible.
- Controls: Test medium without test substance or other additives was used as a blank-control

Test organisms

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM
- Common name: Carp
- Source: Zodiac, proefacc, "De Haar Vissen", L.U. Wageningen, The Netherlands
- Length at study initiation (length definition, mean, range and SD): 3.26 ± 0.23 cm
- Weight at study initiation (mean and range, SD): 1.04 ± 0.20 g
- Method of breeding: F1 from a single parent-pair bred in UV-treated water

ACCLIMATION
- Acclimation period: At least 12 days after delivery.
- Type and amount of food: Trouvit
- Feeding frequency: Daily
- Health during acclimation (any mortality observed): In the batch of fish used for the test, mortality during the seven days prior to the start of the
test was less than 5%.

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Test conditions

Hardness:

Water hardness 250 mg CaCO3/l

Test temperature:

The temperature of the test medium measured in all test vessels ranged from 20.0 to 21.4 °C

pH:

7.5-8.1

Dissolved oxygen:

6.6-9.3 mg/l

Salinity:

Not relevant

Nominal and measured concentrations:

Nominal concentrations: 5.6, 10, 18, 32 and 56 mg/l
For measured concentrations see additional information on materials and methods.

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: 13 litres, all-glass
- Aeration: No aeration during the test
- Renewal rate of test solution (frequency/flow rate): Daily renewal of test solutions
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.61 g fish/litre, i.e. 7 fish per 12 litres of test medium

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: ISO-medium, formulated using Milli-Ro water (tap-water purified by reverse osmosis; Millipore Corp., Bedford, Mass., USA) with the following composition: Ca2+: 80 mg/l; Mg2+: 12 mg/l; Na+: 15 mg/l; K+: 3 mg/l; Cl-: 145 mg/l; SO4 2-: 49 mg/l; HCO3-: 47 mg/l; CaCO3: 250 mg/l
- Culture medium different from test medium: no
- Intervals of water quality measurement: Dissolved oxygen content, pH and temperature of the medium: daily in all vessels, beginning at the start of
the test (day 0). Inadvertently, no measurements were performed on the last day of the test period.

OTHER TEST CONDITIONS
- Photoperiod: Test vessels were protected from light

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Mortality and other effects measured at 2 hours and 20 minutes and 24, 48, 72 and 96 hours following the start of exposure.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.8
- Range finding study
- Test concentrations: 0.1, 1, 10 and 100 mg/l.
- Results used to determine the conditions for the definitive study: All fish died at 100 mg/l during the 96-hour exposure period. Hence, the LC50
for carp exposed to dihydrolinalool appeared to be between 10 and 100 mg/l. Analytical results of samples taken from nominal 10 mg/l during the range-finding test showed that dihydrolinalool concentrations decreased by 40% after 96 hours, but could be maintained at more than 80% of initial
during the first 24 hours. Based on these data, further testing was performed under semi-static conditions with daily renewal of the test solutions.

Reference substance (positive control):

yes

Remarks:

A reference test with pentachlorophenol was carried out from 17-01-2000 to 21-01-2000

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

2.5 h

Dose descriptor:

LC50

Effect conc.:

42 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 2

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

42 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL: 32-56 mg/l

Effect concentrations 3

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 4

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

5.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Effect concentrations 5

Duration:

2.5 h

Dose descriptor:

LC100

Effect conc.:

56 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: Hypoactive swimming and loss of equilibrium
- Mortality of control: 0% mortality in control
- Other adverse effects control: no abnormalities

Results with reference substance (positive control):

- Results with reference substance valid? During the test the pH, oxygen concentration and the temperature of the medium were within the optimal
ranges for fish.
- LC50: 24h-LC50: 0.18 mg/l, 96h-LC50: 0.14 mg/l (95% CI 0.13-0.18 mg/l), already reached at 48h.
- Other: 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 approximately every 3 months since April 1988. The carp originating from this batch can be considered as relatively sensitive to toxic substances.

Reported statistics and error estimates:

The LC50 could not be determined using the maximum likelihood estimation method with the probits of the percentages of dead fish as function of
the logarithms of the corresponding concentrations (Finney, D.J., 1971: Probit analysis, Cambridge University Press, Cambridge, U.K., 3rd edition).
This was because there was no concentration between the highest concentration (A) at which 0% mortality and the lowest concentration (B) at which
100% mortality occurred. Instead the LC50 was calculated as (AB)1/2, with A and B being limits of the 95% confidence level.

Any other information on results incl. tables

Sublethal observations / clinical signs:

Not relevant.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

No mortality in the control group, oxygen concentration > 60% of saturation value, exposure concentration > 80% of initial concentration, the test system was optimized to expose fish to original molecules of test substance

Conclusions:

The 96h LC50 of Dihydrolinalool to carp was reached after ca. 2.5 hours of exposure and was 42 mg/l, with 95% confidence interval 32 - 56 mg/l.

Executive summary:

The toxicity of Dihydrolinalool to carp (Cyprinus carpio) was determined in a 96-hour semi-static test according to the OECD Guideline for Testing of Chemicals No. 203 (1992), under GLP. Validity criteria for the test were met. The 96h LC50 was reached after ca. 2.5 hours and was found to be 42 mg/l (95%-confidence interval 32 -56 mg/l). The NOEC was 5.6 mg/l.