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Environmental fate & pathways

Biodegradation in water: screening tests

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Administrative data

Endpoint:
biodegradation in water: screening tests
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
supporting study
Study period:
No data
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Acceptable, well-documented publication which meets basic scientific principles, on closely-related compound (the laevo enantiomer and minor component of the registered substance). Enantiomers tend to have similar biodegradation potential.

Data source

Reference
Reference Type:
publication
Title:
Degradation of α-pinene oxide and [2H7]-2,5,6-trimethyl-hept-(2E)-enoic acid by Pseudomonas fluorescens NCIMB 11761
Author:
Zorn H, Neuser F, Berger RG
Year:
2004
Bibliographic source:
Journal of Biotechnology 107, 255-263

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Batches of α-pinene oxide added every 15 minutes to a 100 ml cell suspension of Pseudomonas fluorescens for 3 or 5 hours. Sampling was carried out shortly before the test substance was added on each occasion, with the presence of metabolites (and the unconverted substrate) measured by gas chromatography.
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Test material form:
not specified
Details on test material:
- Name of test material (as cited in study report): (-)-α-pinene oxide
- Molecular formula (if other than submission substance): C10-H16-O
- Molecular weight (if other than submission substance): 152.235
- Smiles notation (if other than submission substance): C1([C@@H]2[C@]3(O[C@H]3C[C@@H]1C2)C)(C)C
- InChl (if other than submission substance): 1S/C10H16O/c1-9(2)6-4-7(9)10(3)8(5-6)11-10/h6-8H,4-5H2,1-3H3/t6-,7-,8+,10-/m1/s1
- Structural formula attached as image file (if other than submission substance): see Fig. 1
- Substance type: no data
- Physical state: no data
- Analytical purity: no data
- Impurities (identity and concentrations): no data
- Composition of test material, percentage of components: no data
- Isomers composition: no data
- Purity test date: no data
- Lot/batch No.: no data
- Expiration date of the lot/batch: no data
- Stability under test conditions: no data
- Storage condition of test material: no data

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
other: Pseudomonas fluorescens NCIMB 11761
Duration of test (contact time):
>= 3 - <= 5 h
Initial test substance concentrationopen allclose all
Initial conc.:
152 mmol/L
Based on:
other: total of 12 additions of 12.7 mmol/L provided at 15 minute intervals over a 3-hr period
Initial conc.:
571 mmol/L
Based on:
other: total of 18 additions of 31.7 mmol/L provided at 15 minute intervals over a 5-hr period

Results and discussion

% Degradationopen allclose all
Parameter:
other: aldehyde yield
Value:
ca. 56
Sampling time:
3 h
Remarks on result:
other: without Lewatit
Parameter:
other: aldehyde yield
Value:
ca. 67
Sampling time:
3 h
Remarks on result:
other: with Lewatit
Parameter:
other: aldehyde yield
Value:
ca. 63
Sampling time:
5 h
Remarks on result:
other: without Lewatit
Parameter:
other: aldehyde yield
Value:
ca. 66
Sampling time:
5 h
Remarks on result:
other: with Lewatit
Details on results:
In the 3-hour experiment, a continuous accumulation of isonovalal started after the second dose, and substrate concentration remained at a low steady state level (of about 2 g/L, about 12.7 mmol/L). The concentration of novalal increased slowly from 0 to almost 1 g/L at 3 hours. Other volatiles were found in traces. [Similar data is not provided for the 5-hour experiment.]

Applicant's summary and conclusion

Validity criteria fulfilled:
not specified
Interpretation of results:
other: rapidly degraded under test conditions
Conclusions:
In a non-guideline study, the closely related substance L-pinene alpha epoxide was very rapidly degraded [removal of the epoxide group at least] following a 3- or 5-hour incubation with Pseudomonas fluorescens.
Executive summary:

In a good-quality, non-guideline study, the degradation of the closely-related compound L-pinene alpha epoxide has been evaluated in Pseudomonas fluorescens.

L-pinene alpha epoxide was added in regular batches to a 100 ml bacterial cell suspension [bacterial concentration not given]. Shortly before this, 1 ml samples were taken for analysis by gas chromatography. In a 3-hour test, 1.27 mmol was added every 15 minutes (total dose 15.24 mmol). A similar 5-hour test was conducted, in which 3.17 mmol was added every 15 minutes (total dose 57.06 mmol). Each test was conducted with and without Lewatit, which was used to collect metabolites before conversion to substances not amenable to gas chromatography.

In the 3-hour test, 56% and 67% of the administered dose was recovered as volatile aldehydes, with and without Lewatit, respectively. In the 5-hour test, recovery was 63% and 66% with and without Lewatit. The key detected metabolite was isonovalal [predicted as readily biodegradable in EPISuite], while levels of novalal and trace volatiles were also seen to increase.

Under the conditions of this study, L-pinene alpha epoxide was very rapidly degraded [removal of the epoxide group at least] when incubated with P. fluorescens. It is expected that the dextro enriched form will also be rapidly degraded. Enantiomers tend to have similar biodegradation potential.