Diisobutyl adipate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

OECD SIDS

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

Deviations:

no

GLP compliance:

yes

Inoculum or test system:

activated sludge, non-adapted

Remarks:

Japanese standard activated sludge

Duration of test (contact time):

ca. 28 d

Key result

Parameter:

half-life in days (QSAR/QSPR)

Value:

ca. 1 850

Sampling time:

28 d

Remarks on result:

readily biodegradable based on QSAR/QSPR prediction

Key result

Parameter:

% degradation (O2 consumption)

Value:

>= 86 - <= 95

Sampling time:

28 d

Remarks on result:

readily biodegradable based on QSAR/QSPR prediction

Key result

Parameter:

% degradation (test mat. analysis)

Remarks:

GC analysis

Value:

>= 100

Sampling time:

28 d

Remarks on result:

readily biodegradable based on QSAR/QSPR prediction

Details on results:

Readily biodegradable:
86-95% (BOD) in 28 days,
100% (GC) in 28 days

Type: aerobic [X]; anaerobic [ ]

Inoculum: adapted [ ]; non-adapted [X];

Concentration of 100 mg/l related to Test Substance [X]

the chemical:

Medium: water[ ];water-sediment[ ];soil [ ];sewage treatment [ ]

other [Japanese standard activated sludge]

Degradation: Degree of degradation after 28 days

89; 95; 86 % from BOD

100, 100 and 100 % from GC analysis

Results: Readily biodeg. [X]; Inherently biodeg. [ ]; under test condition no

biodegradation observed [ ]

Method: OECD Test Guideline 301 C

GLP: Yes [X] No [ ] ? [ ]

Test substance: Dibutyl adipate

Reference: MITI (1994b)

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

If released into water, this substance is readily biodegraded (MITI (I), corresponding to the OECD 301C: 86 - 95 % during 28 days based on BOD and 100 % based on GC analysis) (MITI, Japan, 1994b).

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

Version / remarks:

adopted in 1984

Deviations:

no

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

Source of inoculum/activated sludge: obtained from municipal laboratory wastewater treatment plant (16 Mar 1987)
- Concentration of sludge: 30 mg/L (in test)

Duration of test (contact time):

ca. 28 d

Initial conc.:

ca. 52 - 200 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Number of culture flasks/concentration: 100 mg/L: 3 replicats; 52/200 mg/L: two replicats
- pH: 6.8 - 7.8

CONTROL AND BLANK SYSTEM
- Toxicity control: yes

Reference substance:

aniline

Remarks:

100 mg/L

Key result

Parameter:

% degradation (O2 consumption)

Value:

>= 90 - <= 100

Sampling time:

28 d

Details on results:

- lag phase 3 day
- > Manometric Respirometry test60% degradation after 10 days
- biodegradation degree after 28 days: >90%
The test substance is readily biodegradable.

Results with reference substance:

The toxicity control indicates that the test substance is not inhibitory to activated sludge microorganisms (> 90% degradation after 14 days)

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test substance reached a biodegradation of 90 - 100% in 28 days. The 10-day-window was passed. Therefore, the test substance is readily biodegradable according to OECD criteria.

Executive summary:

The ready biodegradability of Bis(2-ethylhexyl) adipate was tested according to EU method C.4-D (manometric respirometry test equivalent to OECD 301F) under GLP conditions. Non-adapted municipal activated sludge was used as inoculum. The test substance was tested at concentrations between of 52 and 200 mg/L. The validity criteria are fulfilled. The pass level of 60% biodegradation was reached in less than 10 days. After 28 days a biodegradation of 90 – 100 % was observed. Therefore, the test substance is readily biodegradable according to OECD criteria.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable