1,1,2,3,3-pentafluoro-3-(heptafluoropropoxy)prop-1-ene

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 Sep - 11 Oct 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1,1,2,3,3-pentafluoro-3-(heptafluoropropoxy)prop-1-ene

EC Number:

817-766-4

Cas Number:

91891-42-8

Molecular formula:

C6F12O

IUPAC Name:

1,1,2,3,3-pentafluoro-3-(heptafluoropropoxy)prop-1-ene

Test material form:

liquid

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: MA-3-HO-ANL 1600356
- Expiration date of the lot/batch: 31 Aug 2020
- Purity test date: 05 Feb 2018
- Purity: 96.9%
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature container flushed with nitrogen
- Stability under test conditions: Yes

Other: ThOD calculated to be 0.25 mg O2/mg

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Remarks:

predominantly domestic

Details on inoculum:

- Source of inoculum/activated sludge: Activated sludge from the 'Waterschap Aa en Maas' municipal sewage treatment plant ('s-Hertogenbosch, The Netherlands), receiving predominantly domestic waste.
- Storage conditions: Continuous aeration until use.
- Storage length: Not reported ("freshly obtained")
- Preparation of inoculum for exposure: Before use, the sludge was coarsely sieved (1 mm) and washed with mineral medium.
- Concentration of sludge: 3 g SS/L

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

315 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

80 mg/L

Based on:

ThOD

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: Mineral medium as per method TG301, water was purified by reverse osmosis and subsequently passed over activated carbon (Millipore, Bedford, MA, USA)
- Solubilising agent: none
- Test temperature: 22-23 °C
- pH: 7.6-7.7 on day 0, 7.7-8.7 on day 28
- pH adjusted: no
- Suspended solids concentration: 6 mg SS/L
- Continuous darkness: no

TEST SYSTEM
- Culturing apparatus: brown glass bottles with automatic respirometer head. Bottles held in a incubator with inductive stir motor
- Number of culture flasks/concentration: two
- Method used to create aerobic conditions: continuous stirring.
- Measuring equipment: Lovibond BD600-GLP manometric respirometry system. Decrease in air pressure due to respiration was measured by the respirometer heads and automatically converted into oxygen consumption (mg O2/L).
- Details of trap for CO2 and volatile organics if used: Two NaOH pellets held by a rubber gasket in each bottle
- Measurement frequency: Oxygen utilization was recorded on days 0, 4, 7, 11, 14, 18, 21, 25, and 28.

CONTROL AND BLANK SYSTEM
- Inoculum blank: duplicate
- Abiotic sterile control: none
- Procedural control: single
- Toxicity control: single, containing both reference and test substance at 80 mg ThOD/L

Reference substance

Reference substance:

acetic acid, sodium salt

Remarks:

80 mg ThOD/L

Results and discussion

% Degradation

Key result

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

28 d

Remarks on result:

other: Oxygen consumption less than in blanks

Details on results:

At all time points, oxygen consumption in test bottle A was less than in blank bottles (Table 1). At all time points after day zero, oxygen consumption in test bottle B was less than the measurement range of the equipment and was reported as zero before comparison with blank.

The reference substance was 68% degraded by day 7 and 78% degraded by day 14 (Table 2). Biodegradation in the toxicity control (Table 3) was 33% by day 7 and 35% by day 14. Therefore, MA-3 is not toxic to activated sludge

Any other information on results incl. tables

Table 1, Oxygen consumption (mg O2 g/L) in the blanks

Day	Blank 1	Blank 2	Mean blank
0	0	0	0
4	2	5	4
7	3	6	5
11	5	7	6
14	7	8	8
18	7	8	8
21	8	7	8
25	9	9	9
28	9	9	9

Table 2, Oxygen Consumption (mg O2/L) and Percentage Biodegradation in the Procedure Control

Day	Mean blank	Reference substance	BOD	%BOD
0	0	1	1	1
4	4	59	56	69
7	5	68	64	79
11	6	74	68	85
14	8	78	71	88
18	8	79	72	89
21	8	80	73	91
25	9	82	73	91
28	9	83	74	93

Table 3 Oxygen Consumption (mg O2/L) and Percentage Biodegradation in the Toxicity Control

Day	Mean blank	Reference substance	BOD	%BOD
0	0	0	0	0
4	4	50	47	29
7	5	57	53	33
11	6	60	54	34
14	8	64	57	35
18	8	57	50	31
21	8	54	47	29
25	9	57	48	30
28	9	59	50	31

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

DO uptake in blanks < 60 mg/L at end of test. Reference substance pass by day 14, <20% difference in biodeg for test material

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

MA-3 was 0% biodegraded in a 28-day OECD 301F test.

Executive summary:

Ready biodegradability of MA-3 was studied in a test done according to OECD TG 301F. MA-3, sodium acetate (reference substance), or both chemicals (toxicity control) were introduced to respirometer bottles at 80 mg/L theoretical oxygen demand (ThOD). Bottles also contained mineral medium inoculated with activated sludge from a predominantly domestic source. Blank bottles containing only inoculated medium were also prepared. Oxygen utilization was monitored automatically at defined intervals. No degradation of MA-3 was measured after 28 days of incubation. The blank bottles had <60 mg/L oxygen utilization at end of test, and the reference substance was >60% degraded by day 14. The toxicity control exhibited sufficient degradation (>25% by 14 days) that MA-3 was considered to have not inhibited microbial actitivity in this test. Since MA-3 was not biodegraded in this test, it is not readily biodegradable.

This test was conducted under an internationally accepted guideline suitable for volatile chemicals, and was in accord with GLP criteria. Therefore, this study is reliable without restrictions.