Registration Dossier

Administrative data

Endpoint:
activated sludge respiration inhibition testing
Type of information:
experimental study
Adequacy of study:
key study
Study period:
15th March 2019
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2019
Report Date:
2019

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test (Carbon and Ammonium Oxidation))
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid

Test solutions

Vehicle:
no

Results and discussion

Effect concentrations
Key result
Remarks on result:
not determinable because of methodological limitations
Remarks:
Result not determined as test item was completely lost to the atmosphere within 10 minutes.
Details on results:
After 5 minutes of the test item being exposed to air, an 85% loss of test item was observed with a 100% loss of test item after 9 minutes.
These results indicated that the test item was extremely volatile.

Applicant's summary and conclusion

Conclusions:
HCFO-1233yd (Z) is extremely volatile. 100% of test item was lost to the atmosphere after 9 minutes.

The calculated Henry’s law constant would suggest that, following the guidance given in the OECD Draft Guidance Document on Aquatic Toxicity Testing of Difficult Substances and Mixtures, significant losses of the test item due to volatilisation may occur under the test conditions employed in a Toxicity to Activated Sludge in a Respiration Inhibition Test, therefore making it not technically possible to conduct this study.

Alternative tests such as a nitrification inhibition test (ISO 9509:2006) are also not suitable for this test item due to its high volatility as this method is only applicable to non-volatile chemicals.

It is therefore considered scientifically justifiable to omit the Toxicity to Activated Sludge in a Respiration Inhibition Test from the testing program for HCFO-1233yd(Z).
Executive summary:

Preliminary work for an Activated Sludge Respiration Inhibition study was conducted using the test material HCFO-1233yd(Z). The test item was weighed onto a watch glass and measurements were taken at 5 and 9 minute time points. Due to the volatility of the test item, 85% had been lost to the atmosphere after 5 minutes. After 9 minutes, 100% of the test item had been lost.

Due to this high volatility, it is not scientifically possible to conduct other similar methods.