Reaction products of 2-methylimidazole and 2,2'-[(1-methylethylidene)bis(4,1-phenyleneoxymethylene)]bisoxirane

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:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Reaction products of 2-methylimidazole and 2,2'-[(1- methylethylidene)bis(4,1-phenyleneoxymethylene)]bisoxirane

EC Number:

701-436-0

Molecular formula:

(C15H16O2.C4H6N2.C3H5ClO)x

IUPAC Name:

Reaction products of 2-methylimidazole and 2,2'-[(1- methylethylidene)bis(4,1-phenyleneoxymethylene)]bisoxirane

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

As per IUCLID5 Sections 1.1. 1.2. 1.4. and 4.1.

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

Stock solutions were prepared at concentrations of 25, 50, 100 and 200 mg/L by adding the required nominal amount of test substance in the diluent, algal stock culture medium (Woods Hole) with EDTA up to 0300 mg/L and and mixing the solution for approximately 1 hour.

Test organisms

Test organisms (species):

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

Details on test organisms:

The green algae Pseudokirchneriella subcapitata was used for the study. The stock cultures were maintained by STILLMEADOW, Inc. cultures in 250-mL sterile Erlenmeyer flasks with stoppers and aeration tubing containing Algal stock culture medium (Woods Hole) with EDTA up to 0.30 mg/L. The test containers received constant aeration and continuous lighting (400 ± 40 ft. c.). The temperature was maintained at 23-25°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:

23-25°C

pH:

7.6-7.7 control cultures, 8.6-8.9 test substance treated cultures.

Dissolved oxygen:

Saturated

Salinity:

No data

Nominal and measured concentrations:

6.25, 12.5, 25, 50 and 100 mg/L, nominal.

Details on test conditions:

The test was conducted using concentrations of 6.25, 12.5, 25, 50 and 100 mg/L of the test substance. The test culturesat 50,000 cells/mL
were divided into 250-mL flasks containing the appropriate concentration of test substance (three flasks for each 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 test initiation, the pH was measured in the control and 100 mgfL concentration. 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.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Details on results:

Based on relative cell number the mean percent survival of the 25 mg/L test substance concentratioin wwas 67% and the relative percent survival at 100 mg/L was 54 % after 72 hr of exposure.

Results with reference substance (positive control):

The mean relative survival of the positive control 10 mg/L zinc chloride cultures was 1.56 % at 24 hr and 0.48 % at 72 hr of exposure.

Reported statistics and error estimates:

he NOEC and EC50 were determined by a commercially available statistical program (ToxCalc Version 5.OTM). The Linear Interpolation model was selected for the determination of the values in this study.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 72 hr EC50 value based on mean relative cell number was > 100 mg/L of test substances. The mean relative percent survival was approximately 54 % at a test substance concentration of 100 mg/L after 72 hr of exposure.

Executive summary:

The test substance, Bisphenol A, epichlorohydrin polymer, 2-methylimidazole condensate, was accessed for toxicity to green algae in an O.E.C.D. test guideline 201 study. The 72 hr EC50 value based on mean relative cell number was > 100 mg/L of test substances. The mean relative percent survival was approximately 54 % at a test substance concentration of 100 mg/L after 72 hr of exposure.