3,7-dimethylnon-6-en-1-yn-3-ol

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: well documented guideline study

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

3,7-dimethylnon-6-en-1-yn-3-ol

EC Number:

246-061-9

EC Name:

3,7-dimethylnon-6-en-1-yn-3-ol

Cas Number:

24173-47-5

Molecular formula:

C11H18O

IUPAC Name:

3,7-dimethylnon-6-en-1-yn-3-ol

Test organisms

Test organisms (species):

Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)

Study design

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

12 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

4.6 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Any other information on results incl. tables

-

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

ETHYLDEHYDROLINALOOL reduced growth rate of this fresh water algae species
significantly at 22 mg/l and higher.

Executive summary:

A range-finding test preceded the final test to provide information about the range of concentrations to be used in the final test. Algae were exposed to a range of 0.1 to 100 mg/l, increasing by a factor 10. The results showed that algal cell growth was inhibited less than 10% at 0.1 and 1 mg/1. At 10 mg/l algal cell growth was inhibited by 53% and at 100 mg/l inhibition was almost complete at 95%. The EC50 for inhibition of algal cell growth was expected to be approximately 10 mg/l. After the range-finding test, a final EC50 test was performed exposing exponentially growing algal cultures to ETHYLDEHYDROLINALOOL concentrations of 0.46, 1.0, 2.2, 4.6, 10, 22 and 46 mg/1. The initial cell density was 10⁴ cells/ml. The total test period was 72 hours. Samples for determination of actual exposure concentrations were taken at the start and the end of the test period. Analysis of the samples was based on the two major peaks observed in the chromatograms from ETHYLDEHYDROLINALOOL, i.e. the components ETHYLDEHYDROLINALOOL-1 and ETHYLDEHYDROLINALOOL-2. Analysis of the samples taken during the final test showed that the measured concentrations at the concentrations necessary for determination of the toxicity parameters were in agreement with nominal. ETHYLDEHYDROLINALOOL reduced growth rate 1 of this fresh water algae species significantly at 22 mg/l and higher.