2,2'-dihydroxy-4,4'-dimethoxybenzophenone

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:

1991-05-14 - 1991-06-11

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

no

Remarks:

The test was not conducted according to GLP guidance but according to GLP-compliant guidance. Accordingly, the study is documented in compliance with GLP but a statement of the quality assurance is not required.

Test material

Test material information

Constituent 1

Reference substance name:

2,2'-dihydroxy-4,4'-dimethoxybenzophenone

EC Number:

205-027-3

EC Name:

2,2'-dihydroxy-4,4'-dimethoxybenzophenone

Cas Number:

131-54-4

Molecular formula:

C15H14O5

IUPAC Name:

2-(2-hydroxy-4-methoxybenzoyl)-5-methoxyphenol

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 03-3849

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Stability under test conditions: Stability to Hydrolysis, Photolysis, Oxidation and Temperatures up to 100 °C is warranted according to the information of the sponsor.

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): activated sludge taken from a laboratory scale waste water treatment plant (K 210) of the test facility (BASF AG, Emissionsüberwachung und ökoloqie ( DUO) Labor für Ökologie ( DUU/OO ) K 210, 6700 Ludwigshafen/Rhein, Germany); the inoculum for the lab scale fermenter was muncipal activated sludge without pre-treatment
- dry solids: 1 g/L
- Preparation of inoculum for exposure: washing
- Concentration of washed sludge: 750 mg/L (used as inoculum),
- Final concentration in the treatment groups: 30 mg/L
- Water filtered: no

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

other: The biological oxygen demand (BOD) was measured over a 28-day period. After this period, amounts of the dissolved organic carbon (DOC) and residual test substance were measured. The biodegradability of the test substance was evaluated from these results.

Details on study design:

TEST CONDITIONS
- Composition of medium: according to OECD 301 C
- Additional substrate: none
- Solubilising agent (type and concentration if used): none
- Test temperature: 22 ± 2 °C. according to EEC 79/831 Annex V, Methods for determination of ecotoxicity, Biodegradation Part IV,
Manometric Respirometry (Method C.4-D)
- pH: 6,7 - 7,2
- pH adjusted: no
- Suspended solids concentration: 30 g/L
- Continuous darkness: yes (closed Sapromat)

TEST SYSTEM
- Culturing apparatus: Respirometer (Sapromat, not further specified)
- Number of culture flasks/concentration: one concentration of test item with 7 flasks; two controls, toxicity control, aboiotic control, reference item (positve control)
- Method used to create aerobic conditions: constant O2 partial pressure (Sapromat)
- Measuring equipment: Sapromat integrated control
- Test performed in closed vessels due to significant volatility of test substance: no
- Test performed in open system: no
- Details of trap for CO2 and volatile organics if used: soda lime

SAMPLING
- Sampling frequency: integrated closed system with automatic data logging

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes, 2 flasks
- Abiotic sterile control: yes, 1 flask
- Toxicity control: yes, 1 flask

Reference substance

Reference substance:

aniline

Results and discussion

Test performance:

There was no specific factor which might have affected the reliability of the test results.
The test was judged valid since the measurement results fulfilled all of the validity criteria of the guideline.

% Degradation

Key result

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

28 d

Details on results:

Due to the lack of biodegradation, no substance specific analysis has been conducted.

BOD5 / COD results

BOD5 / COD

BOD5 / COD 1

Key result

Parameter:

BOD5

Value:

0 mg O2/g test mat.

BOD5 / COD 2

Parameter:

COD

Value:

1 940 mg O2/g test mat.

BOD5 / COD 3

Parameter:

ThOD

Value:

1 831 mg O2/g test mat.

Results with reference substance:

The reference substance Alinin showed a degradation of 63% after 9 days.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The test item is not readily biodegradable. Maximum Biodegradation in the respirometric study was 0% ThOD and 0% COD.
The test guideline validity criteria were fulfilled.
The test item is not inhibitory to activated sludge based on toxicity control.
The test item is not inhibitory to activated sludge based on activated sludge respiration inhibition test.

Executive summary:

Biodegration of the test item has been conducted by means of an OECD 301 C test. Prior to the test, bacterial respiration inhibition (OECD 209), water solubility, chemical oxygen demand (DOC) and biochemical oxygen demand (BOD/ThOD) were determined. Primary biodegradation has not been assessed.

The test item is considered to be not readily biodegradable. The test item does not inhibit bacterial respiration and activity.