Triisononyl benzene-1,2,4-tricarboxylate

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:

2018-02-21 - 2018-04-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

Deviations:

yes

Remarks:

Ammonium chloride excluded from medium to prevent oxygen consumption as a result of nitrification / river water used as inoculum

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

trinonyl trimellitate

IUPAC Name:

trinonyl trimellitate

Details on test material:

Physical state at 25°C: Liquid
Storage conditions: Keep container tightly closed. Keep in a dry, cool and well ventilated place.
Lot number: 3607211300
Expiry date: The product TM 9 due to its nature does not have expiry date.
Purity: 99.98% w/w
Date received: 15 November 2011
Storage at testing facility: 5 years

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source: Commercial batch
- Lot/batch No.of test material: 2103218004
- Purity: 99.9%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Ambient conditions, in the dark
- Stability under test conditions: Stable

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: None

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

natural water: freshwater

Details on inoculum:

- Source of inoculum/activated sludge: River water from the Rhine near Heveadorp, The Netherlands. The nearest plant (Arnhem-Zuid) treating domestic wastewater biologically was 3 km upstream of the sampling site.
- Pretreatment: Aerated for 7 days before use to reduce the endogenous respiration. River water without particles was used as inoculum. The particles were removed by sedimentation after 1 day while moderately aerating.

Duration of test (contact time):

60 d

Initial test substance concentration

Initial conc.:

2 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: As per OECD TG 301 less ammonium chloride (to prevent nitrification)
- Solubilising agent (type and concentration if used): Tween 80, 2.0 mg/L
- Test temperature: 22.6 - 23.0 deg C
- pH: 8.0
- pH adjusted: No
- Continuous darkness: Yes

TEST SYSTEM
- Culturing apparatus: 300 mL BOD bottles
- Number of culture flasks/concentration: 10
- Method used to create aerobic conditions: Aeration of inoculum
- Measuring equipment: Oxygen electrode

SAMPLING
- Sampling frequency: Days 0, 7, 14, 21, 28, 42 and 60

CONTROL AND BLANK SYSTEM
- Inoculum blank: Yes
- Other: Yes - bottles containing inoculum + surfactant

Reference substance

Reference substance:

acetic acid, sodium salt

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

0 d

% Degradation 2

Parameter:

% degradation (O2 consumption)

Value:

2

Sampling time:

7 d

% Degradation 3

Parameter:

% degradation (O2 consumption)

Value:

15

Sampling time:

14 d

% Degradation 4

Parameter:

% degradation (O2 consumption)

Value:

29

Sampling time:

21 d

% Degradation 5

Parameter:

% degradation (O2 consumption)

Value:

46

Sampling time:

28 d

% Degradation 6

Parameter:

% degradation (O2 consumption)

Value:

63

Sampling time:

42 d

% Degradation 7

Parameter:

% degradation (O2 consumption)

Value:

71

Sampling time:

60 d

BOD5 / COD results

Results with reference substance:

76% degrdation after 14 days

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

inherently biodegradable

Conclusions:

The substance was biodegraded by 46% at day 28 in the Closed Bottle test. In the prolonged Closed Bottle test (enhanced biodegradability test) the substance was biodegraded by 71% within 60 days.
The biodegradation percentage of >60% demonstrates that test substance is inherently biodegradable. Moreover, the biodegradation in excess of 60% within the 60-day test period allows classification of the substance as not persistent

Executive summary:

Biodegradation has been studied in the Closed Bottle test, performed according to slightly modified EEC, OECD and ISO Test methods.

The substance was biodegraded by 46% at day 28 in the Closed Bottle test. In the prolonged Closed Bottle test (enhanced biodegradability test) the substance was biodegraded by 71% within 60 days.

The biodegradation percentage of >60% demonstrates that test substance is inherently biodegradable. Moreover, the biodegradation in excess of 60% within the 60-day test period allows classification of the substance as not persistent