Cyclohexylbenzene

Phototransformation in water

Administrative data

Endpoint:

phototransformation in water

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented report which meets basic scientific principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1983

Report date:

1983

Materials and methods

Study type:

direct photolysis

Test guideline

Qualifier:

no guideline followed

Deviations:

not applicable

Principles of method if other than guideline:

As developed in Saeger V.W. and Adams W.J. “Method for conducting Sunlight photolysis screening of organic chemicals in aqueous solution”, Monsanto Report ES-81-M-23.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Cyclohexylbenzene

EC Number:

212-572-0

EC Name:

Cyclohexylbenzene

Cas Number:

827-52-1

Molecular formula:

C12H16

IUPAC Name:

cyclohexylbenzene

Details on test material:

Lot N°: 091187
Source: Aldrich

Study design

Radiolabelling:

no

Analytical method:

gas chromatography

Details on sampling:

Sampling for the parent compounds: day 0, 1, 3, 7, 14 and 29

Light source:

sunlight

Duration of test at given test condition

Duration:

29 d

Temp.:

90 °F

Initial conc. measured:

20 other: ppm

Results and discussion

% Degradation

% Degr.:

0

Sampling time:

29 d

Transformation products:

not specified

Any other information on results incl. tables

The results of the photolysis study on the 3 isomers are summarized below. The concentrations found for each sampling day are expressed as a percentage of the concentration pound at day 0.

It can be seen that for cyclohexylbenzene, no degradation occurred both in the dark and sunlight-exposed test tubes.

Sampling day	Cyclohexylbenzene % remaining
0	100
1 – Exposed 1 – Dark	105 110
3 – Exposed 3 – Dark	103 109
7 – Exposed 7 – Dark	112 119
14 – Exposed 14 – Dark	100 100
29 – Exposed 29 – Dark	109 112

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Cyclohexylbenzne was tested for direct photolysis with sunlight during a 29 day period. No significant decrease in concentration after 29 days of sunlight exposure was observed, indicating that cyclohexylbenzene are not susceptible to direct aqueous photolysis by sunlight.

Executive summary:

Polyphenyls are strong absorbers of UV light. It is well established that many compounds that absorb visible and UV light undergo rapid photodegradation in the environment. The purpose of this study was to examine the photolytic behavior of cyclohexylbenzene.

The substance was exposed to sunlight for 29 days as a 20 ppm solution in 50/50 acetonitrile/water. The concentration of cyclohexylbenzene was monitored on days 0, 1, 3, 7, 14 and 29 via GC/FID analysis.

No significant decrease in the concentration of cyclohexylbenzene was observed.