1,1-difluoroethane

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

activated sludge respiration inhibition testing

Data waiving:

other justification

Justification for data waiving:

the study does not need to be conducted because there is no emission to a sewage treatment plant

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
The substance is a gas, no emission to sewage tretment plant.

Reference 2

Endpoint:

toxicity to microorganisms

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Read-across from an analogue substance for which a study is available (Klimish score=4 because secondary source)

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
See attached reporting format.

Analytical monitoring:

yes

Key result

Duration:

6 h

Dose descriptor:

EC50

Effect conc.:

> 472.57 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Remarks on result:

other: Based on a read-across from an analogue from which EC50 > 730 mg/L.

Conclusions:

Based on the read-across approach from the analogue 1,1,1,2-tetrafluoroethane, the EC50 of 1,1-difluoroethane was determined to be > 472.57 mg/l based on growth inhibition.

Executive summary:

A bacterial growth inhibition test was carried out with the analogue substance 1,1,1,2 -tetrafluoroethane on Pseudomonas putida.

HFC-134a showed a low toxicity towards P. putida. At the highest mean measured HFC-134a concentration of 730 mg/l no inhibition of the growth of P.putida was found during a period of 6 h and therefore, the EC50 based on growth inhibition was determined to be > 730 mg/l. On the basis of these results, the read-across approach was applied and the EC50 based on growth inhibition of 1,1 -difluoroethane was determined to be > 472.57 mg/l.

Description of key information

Data waiving: In accordance with Column 2 adaptation statement of REACH Annex VIII the study does not need to be conducted if there as no emission to a sewage treatment plant.

Additional information

Data waiving: In accordance with Column 2 adaptation statement of REACH Annex VIII the study does not need to be conducted if there as no emission to a sewage treatment plant.

Supporting study: A bacterial growth inhibition test was carried out with the analogue substance 1,1,1,2 -tetrafluoroethane on Pseudomonas putida. Based on the read-across approach from the analogue 1,1,1,2-tetrafluoroethane, the EC50 of 1,1-difluoroethane was determined to be > 472.57 mg/l based on growth inhibition.