2,3-epoxypropyl o-tolyl 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:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

yes

Remarks:

Nominal concentrations only.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2,3-epoxypropyl o-tolyl ether

EC Number:

218-645-3

EC Name:

2,3-epoxypropyl o-tolyl ether

Cas Number:

2210-79-9

Molecular formula:

C10H12O2

IUPAC Name:

oxirane

Constituent 2

Reference substance name:

Oxirane, 2-[(2-methylphenoxy)methyl]-

IUPAC Name:

Oxirane, 2-[(2-methylphenoxy)methyl]-

Details on test material:

As per IUCLID Sections 1.1. 1.2. and 4.1.

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

Test substance treatment solutions were prepared by by adding the required nominal amount of test substance in stock culture medium (Woods Hole) and mixing.

Test organisms

Test organisms (species):

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

Details on test organisms:

The green algae Selenastrum capricornutum was maintained by Stillmeadow, Inc. Mass culture initiated 3-7 ±1 days prior to dosing and were used on-study at a density of 50,000 cells/mL. The algal cultures were maintained in Algal stock culture medium (Woods Hole) with EDTA up to 0.300 mg/L in 250-mL sterile Erlenmeyer flasks with stoppers and aeration tubing. The test containers received constant aeration. The temperature was maintained at 24 ±2°C with continuous lighting (400 ±40 ft. 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:

24ºC

pH:

7.4-8.9 treminal

Dissolved oxygen:

no data

Salinity:

Freshwater

Nominal and measured concentrations:

1.25, 2.5, 5, 10 and 20 mg/L nominal.

Details on test conditions:

The five concentrations of the test substance were used. The test cultures (50,000 cells/mL) were divided into 250-mL flasks containing the appropriate concentration of test substance (three flasks per test concentration and six flasks for the 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:

10 mg/L zinc chloride

Results and discussion

Effect concentrations

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 5.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Remarks on result:

other: 95% confidence Limits = 0.0 - 9.85 mg/L nominal

Details on results:

At 10 mg/L test substance after 72 hr the relative percent cell growth inhibition was 35.9%. Complete cell growth inhibition was observed at 20 mg/L of test substance at 72 hr.

Results with reference substance (positive control):

The positve control zinc chloride at 10 mg/L caused complete (100%) cell growth inhibiton at 72 hr relative to the untreated control cultures.

Reported statistics and error estimates:

The EC50 95% Confidence Limits were 0.0 - 9.85 mg/L (nominal).

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The EC50 value for the test substance in this study of 5.1 mg/L demonstrates that it is toxic to algae under the conditions of the study.

Executive summary:

The test substance, 2,3 -epoxypropyl o-tolyl ether, was accesed for toxicity to green algae in a GLP, O.E.C.D. test gudeline 201 study.The EC50 value for the test substance in this study of 5.1 mg/L demonstrates that it is toxic to algae under the conditions of the study.