Registration Dossier

Administrative data

Endpoint:
phototransformation in water
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2007
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to OECD TG 101 and in accordance with the Principles of GLP.
Cross-referenceopen allclose all
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2007
Report Date:
2007

Materials and methods

Study type:
direct photolysis
Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EPA OPPTS 835.2210 (Direct Photolysis Rate in Water by Sunlight)
Deviations:
no
Remarks:
Not specified in the report.
Qualifier:
according to
Guideline:
other: OECD 101
Deviations:
no
Remarks:
Not specified in the report
Principles of method if other than guideline:
not applicable
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Bioban CS-1246
- Molecular formulas: C7H13NO2
- Molecular weight: 143.09
- Physical state: not specified
- Analytical purity: 98.55 %
- Impurities (identity and concentrations): water 0.53 %
- Composition of test material, percentage of components: 5-ethyl-1-aza-3,7-dioxabicyclo[3,3,0]octane (active ingredient)
- Isomers composition: not applicable
- Purity test date: August 24, 2005
- Lot/batch No.: TC1031LAH3
- Expiration date of the lot/batch: not specified in the report
- Storage condition of test material: frozen
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
not applicable

Study design

Radiolabelling:
no
Analytical method:
not specified
Details on sampling:
not applicable
Buffers:
A solution of Bioban CS-1246 in methanol was prepared by diluting 55.97 mg of the test substance to volume in a 50 ml volumetric flask. The final concentration of Bioban CS-1246 in this solution was 7.710 x 10(-3) M (moles/liter)
Light source:
not specified
Light spectrum: wavelength in nm:
200 - 800
Details on light source:
Duplicate scans were analyzed from 200-800 nm, recording the absorbance at 1 nm intervals. The scan parameters were as follows:
- Wavelength accuracy: ± 0.5 nm
- Wavelength repeatability: ± 0.2 nm
- Spectral Bandwidth: ≤ 1.8 nm
- Wavelength range: 200-800 nm
- Scan speed: 1200 nm/min
- Interval: 35 sec
- cell path length (l): 1 cm

The calibration of the DU-640B spectrophotometer was checked prior to use in the study by analyzing a set of sealed standards: benzene vapor for wavelength resolution, samarium perchlorate for wavelength calibration, saturated lithium carbonate for stray light and potassium dichromate for p hotometric accuracy
Details on test conditions:
A UV/Visible absorption experiment was conducted with BIOBAN CS-1246 in methanol to determine the possibility of direct photolysis. The absorbance of the test substance >290 nm was used to predict the half-life of photolysis of the test substance at 40 °N latitude in summer, assuming a quantum yield of 1.
A solution of BIOBAN CS-1246 in methanol was prepared by diluting 55.97 mg of the test substance to volume in a 50 mL volumetric flask. The final concentration of BIOBAN CS-1246 in this solution was 7.710 x 10-3 M (moles/liter). Duplicate scans were analyzed from 200-800 nm, recording the absorbance at 1 nm intervals.
The scan parameters were as follows:
- Wavelength accuracy: ± 0.5 nm
- Wavelength repeatability: ± 0.2 nm
- Spectral Bandwidth: ≤ 1.8 nm
- Wavelength range: 200-800 nm
- Scan speed: 1200 nm/min
- Interval: 35 sec
- cell path length (l): 1 cm
Reference substance:
no
Dark controls:
no
Computational methods:
not applicable

Results and discussion

Preliminary study:
not applicable
Test performance:
A UV/Visible spectrum study was conducted with BIOBAN CS-1246 (5-ethyl-1-aza-3,7-dioxabicyclo[3.3.0]octane) following OECD 101 guidelines. UV/Visible spectral analyses in the wavelength range of 200-800 nm were carried out with BIOBAN CS-1246 solutions prepared in methanol, and adjusted to pH 2 and 10. The absorption maxima ranged from 201 to 209 nm for all solutions tested. Molar absorption coefficients at the UVmax were determined to be 28, 107 and 37 L mol-1 cm-1 at pH <2, 7.6 and >10, respectively.
The UV absorption characteristics of BIOBAN CS-1246 were also investigated as Tier 1 of the aqueous photolysis study following OPPTS 835.2210 guidelines, to determine if there was significant absorbance >290 nm, and thus, the possibility of photolysis. Assuming a quantum yield of 1 and using the spectral data from the test substance in methanol, the maximum half-life was estimated to be 63 days. Based on the results of the Tier 1 experiment, significantly less than 50% photodegradation would occur over a 30-day period, therefore a Tier 2 experiment was not necessary. The results of the study indicate that aqueous photolysis of BIOBAN CS-1246 is not expected to be a major degradation pathway for the test substance in the environment.
Spectrum of substanceopen allclose all
Parameter:
max epsilon
Value:
28 L/(mol cm)
Remarks:
at pH <2
Parameter:
max epsilon
Value:
107 L/(mol cm)
Remarks:
at pH 7.6
Parameter:
max epsilon
Value:
37 L/(mol cm)
Remarks:
at pH >10
Quantum yield (for direct photolysis):
1
Predicted environmental photolytic half-life:
Assuming a quantum yield of 1 and using the spectral data from the test substance in methanol, the maximum half-life was estimated to be 63 days. Based on the results of the Tier 1 experiment, significantly less than 50% photodegradation would occur over a 30-day period, therefore a Tier 2 experiment was not necessary.
Transformation products:
not measured
Details on results:
The absorption maxima ranged from 201 to 209 nm for all solutions tested. Molar absorption coefficients at the UVmax were determined to be 28, 107 and 37 L mol-1 cm-1 at pH <2, 7.6 and >10, respectively.

Based on the results of the Tier 1 experiment, significantly less than 50% photodegradation would occur over a 30-day period, therefore a Tier 2 experiment was not necessary. The results of the study indicate that aqueous photolysis of BIOBAN CS-1246 is not expected to be a major degradation pathway for the test substance in the environment.
Results with reference substance:
not specified in the report

Any other information on results incl. tables

not applicable

Applicant's summary and conclusion

Validity criteria fulfilled:
no
Conclusions:
The results of the study indicate that aqueous photolysis of BIOBAN CS-1246 Biocide is not expected to be a major degradation pathway for the test substance in the environment.
Executive summary:

A UV/Visible spectrum study was conducted with BIOBAN™ CS-1246 Biocide (5- ethyl-1-aza-3,7-dioxabicyclo[3.3.0]octane) following OECD 101 guidelines. UV/Visible spectral analyses in the wavelength range of 200-800 nm were carried out with BIOBAN

CS-1246 solutions prepared in methanol, and adjusted to pH 2 and 10. The absorption maxima ranged from 201 to 209 nm for all solutions tested.

Molar absorption coefficients at the UVmax were determined to be 28, 107 and 37 L mol-1 cm-1 at pH <2, 7.6 and >10, respectively.

The UV absorption characteristics of BIOBAN™ CS-1246 Biocide were also investigated as Tier 1 of the aqueous photolysis study following OPPTS 835.2210 guidelines, to determine if there was significant absorbance >290 nm, and thus, the possibility of photolysis. Assuming a quantum yield of 1 and using the spectral data from the test substance in methanol, the maximum half-life was estimated to be 63 days.

Based on the results of the Tier 1 experiment, significantly less than 50% photodegradation would occur over a 30-day period, therefore a Tier 2 experiment was not necessary. The results of the study indicate that aqueous photolysis of BIOBAN™ CS-1246 Biocide is not expected to be a major degradation pathway for the test substance in the environment.