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Environmental fate & pathways

Phototransformation in water

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Administrative data

Endpoint:
phototransformation in water
Type of information:
other: Technical discussion
Adequacy of study:
supporting study
Study period:
Not available
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Well documented discussion on substance properties

Data source

Referenceopen allclose all

Reference Type:
review article or handbook
Title:
Photoreactivity of selected aromatic hydrocarbons in water
Author:
Zepp, R.G., Schlotzhauer, P.F.
Year:
1977
Bibliographic source:
In: "Polynuclear aromatic hydrocarbons", Jones, P.W., Leber, P., eds., pp. 141-158. Ann Arbor Science Publishers, Inc., Ann Arbor, MI, USA
Reference Type:
publication
Title:
Rates of direct photolysis in the aqueous environment
Author:
Zepp, R., Cline, D.
Year:
1977
Bibliographic source:
Environmental Science and Technology 11: 359-366.
Reference Type:
review article or handbook
Title:
Chapter 8. Rate of aqueous photolysis
Author:
Harris, J.C.
Year:
1982
Bibliographic source:
In:" Handbook of chemical property estimation methods", Lyman, W.J., Reehl, W.F., Rosenblatt, D.H., eds. McGraw-Hill Book Company, New York, USA.
Reference Type:
other: QSAR Estimation
Title:
Unnamed
Year:
1999

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Technical discussion

Test material

Reference
Name:
Unnamed
Type:
Constituent

Results and discussion

Applicant's summary and conclusion

Validity criteria fulfilled:
not applicable
Conclusions:
The substance does not exhibit any potential to undergo phototransformation in water.
Executive summary:

The direct photolysis of an organic molecule occurs when it absorbs sufficient light energy to result in a structural transformation. The absorption of light in the ultra violet (UV) -visible range, 110-750 nm, can result in the electronic excitation of an organic molecule. The stratospheric ozone layer prevents UV light of less than 290 nm from reaching the earth's surface. Therefore, only light at wavelengths between 290 and 750 nm can result in photochemical transformations in the environment.

A conservative approach to estimating a photochemical degradation rate is to assume that degradation will occur in proportion to the amount of light wavelengths >290 nm absorbed by the molecule. This substance contains hydrocarbon molecules that absorb UV light below 290 nm, a range of UV light that does not reach the earth's surface. Therefore, this substance does not have the potential to undergo photolysis in water and soil, and this fate process will not contribute to a measurable degradative loss of this substance from the environment.