p-tert-butylphenyl 1-(2,3-epoxy)propyl ether

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: The study was conducted according to the O.E.C.D. test guideline 201 with GLP compliance.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2210453-2

IUPAC Name:

2210453-2

Constituent 2

Reference substance name:

p-tert-butylphenyl-1-(2,3)-epoxypropyl ether

IUPAC Name:

p-tert-butylphenyl-1-(2,3)-epoxypropyl ether

Constituent 3

Reference substance name:

p-tert-butylphenyl 1-(2,3-epoxy)propyl ether

EC Number:

221-453-2

EC Name:

p-tert-butylphenyl 1-(2,3-epoxy)propyl ether

Cas Number:

3101-60-8

Molecular formula:

C13H18O2

IUPAC Name:

2-[(4-tert-butylphenoxy)methyl]oxirane

Constituent 4

Reference substance name:

Oxirane, 2-((4-(1,1-dimethylethyl)phenoxy)methyl)-

IUPAC Name:

Oxirane, 2-((4-(1,1-dimethylethyl)phenoxy)methyl)-

Test material form:

other: Liquid at room temperature.

Details on test material:

As per IUCLID5 Sections 1.1. 1.2. and 4.1.

Sampling and analysis

Analytical monitoring:

no

Test solutions

Details on test solutions:

A stock solution of the test substance was prepared at a concentration of 20 mg/L by adding the required nominal amount of test substance in the diluent (Algal stock culture medium with EDTA up to 0.300 mg/L) , and mixing the solution for approximately 1.25 hours. Dilution of the test substance stock solution were made as necessary to achieve the required final concentrations.

Test organisms

Test organisms (species):

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

Details on test organisms:

The green algae, Pseudokirchneriella subcapitata was maintained in culture in Algal stock culture medium (Woods Hole) with EDTA up to 0.300 mg/L by Stillmeadow, Inc. The algal cultures were maintained with constant aeration and a temperature of 24 +/- 2°C with Continuous lighting (400 + 40 fi. c.).

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Post exposure observation period:

None

Test conditions

Hardness:

No data

Test temperature:

22-25°C

pH:

7.2-8.3

Dissolved oxygen:

Approximately 100% saturation.

Salinity:

Freshwater based algal culture medium.

Nominal and measured concentrations:

0, 0.625, 1.25, 2.5, 5 and 10 mg/L nominal.

Details on test conditions:

250-mL sterile Erlenmeyer flasks with stoppers and aeration tubing were used for test substance. These test containers received constant aeration. The test cultures were divided into 250-mL flasks containing the appropriate concentration of test substance (three flasks for each test concentration and six flasks for the untreated control). A positive control group consisted of three flasks treated with 10 mg/L zinc chloride The flasks were set on a shaker table for constant agitation at approximately 100 cycles/minute. At 24,48 and 72 hours following dosing, observations of inhibition were made for each test container by measuring the mean cell density with a hemacytometer. The temperature was recorded daily, and the pH of each container was recorded at study termination.

Reference substance (positive control):

yes

Remarks:

Zinc chloride at 10 mg/L.

Results and discussion

Effect concentrations

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Remarks on result:

other: 8.3-9.3 mg/L

Details on results:

Generally, growth inhibition was not observed until 72 hr following initiating of treatment. After 72 hr of exposure the percent grow
th inhibition at the high test substance concentration of 10 mg/L was 40.4% relatuve to the control value.

Results with reference substance (positive control):

At 24 hr the mean relative growth of the positive control zinc chloride cultures was 21.8%. After 72 hr of treatment the relative growth of the positive control was 0.56%.

Reported statistics and error estimates:

EC50 95% confidence Limits = 8.3-9.3 mg/L.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Algal growth inhibition was generally not observed until 72 hr of exposure had occured. The EC50 for growth inhibition was 9.0 mg/L with 95% confidence Limits of 8.3 - 9.3 mg/L.

Executive summary:

The test substance, p-tert-butylphenyl-1-(2,3)-epoxypropyl ether was evaluated for acute toxicity to green algae in an O.E.C.D. test guideline 201 study. Algal growth inhibition was generally not observed until 72 hr of exposure had occured. The EC50 for growth inhibition was 9.0 mg/L with 95% confidence Limits of 8.3 - 9.3 mg/L.