Registration Dossier

Environmental fate & pathways

Additional information on environmental fate and behaviour

Administrative data

Endpoint:
additional information on environmental fate and behaviour
Type of information:
experimental study
Adequacy of study:
key study
Study period:
27 Apr - 28 Apr 2011
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GWP calculation according to standard method, reference compound GWP reproduces literature values exactly

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2011
Report Date:
2011

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other:
Principles of method if other than guideline:
IR spectrum obtained according to EPA method 320, integrated according to Pinnock et al (1995) (J. Geophys. Res., 100, 23227-23238) and used to estimate Global warming potential according to IPCC methods.
GLP compliance:
no
Type of study / information:
Infrared spectrum, global warming potential.

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Perfluoro(4-isopropylmorpholine), PIPM
- Substance type: multi-constituent substance

Results and discussion

Any other information on results incl. tables

See attachment for infrared (IR) spectrum of FC-770. Average cross-section in the absorbance range of ozone (1000 - 1100 cm-1) was 0.10 x 10-18 cm2 molecule-1, which is less than the value (0.148) that would indicate that the radiative forcing should be corrected for confounding by ozone absorbance. Instantaneous radiative forcing was adjusted using a "cloudy-sky" factor of 1.07. The adjusted radiative forcing is 0.71 W∙m-2∙ppbV-1. Assuming an atmospheric lifetime range of 1500-4000 years, the 100-year GWP of FC-770 is 11,200 - 11,400 was calculated for this study summary using the WMO 1998 model with updated CO2 response and forcing. The 100-year GWP is, to a good approximation, independent of lifetime for essentially inert (lifetime >1000 years) compounds. The reported value is rounded to two significant digits for this study summary, for a 100-year GWP of 11,000. A 20-year GWP of 8,100 was also determined.

The 100-year GWP values for reference compounds were determined in a separate study (E11-0095) using the approach described above. The values are essentially identical to those reported in the literature (see Table).

Table, Calculated and reported GWPs for reference compounds

Compound

100 yr GWP

Relative Difference

3M Environment Lab Calculation

IPCC AR4 Report

CF4

7,390

7,390

0%

C2F6

12,200

12,200

0%

C3F8

8,840

8,830

0%

SF6

22,800

22,800

0%

 

Applicant's summary and conclusion

Conclusions:
The 100-year GWP for FC-770 is 11,000
Executive summary:

Potential effects of FC-770 on climate were addressed by calculation of 100-year integrated global warming potential (100-year GWP). A high-resolution infrared spectrum was taken using a protocol following EPA method 320. Integrated IR cross-section and radiative forcing were calculated using the approach of Pinnock et al (J. Geophys. Res., 100, 23227-23238). Atmospheric lifetime was determined elsewhere in this dossier. GWP was calculated for this study summary using the WMO 1998 model with updated CO2 response and forcing. The integrated radiative forcing was 0.71 W∙m-2∙ppbV-1. The 100-year GWP by this method is 11,000. A 20-year GWP of 8,100 was also determined.

No testing guideline has been promulgated to determine global warming potential. However, the infrared cross-section data were collected according EPA method 320, and the radiative forcing and GWP were calculated by methods accepted by IPCC. The overall approach used in this study was able to accurately reproduce GWP of several standard chemicals which have been reported in IPCC literature. Therefore, this study is classified as reliable without restrictions.