4-hydroxy-2-methylnaphthyl benzoate

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: study performed according to OECD and GLP guidelines

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1998

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4-hydroxy-2-methylnaphthyl benzoate

EC Number:

218-647-4

EC Name:

4-hydroxy-2-methylnaphthyl benzoate

Cas Number:

2211-28-1

Molecular formula:

C18H14O3

IUPAC Name:

4-hydroxy-2-methyl-1-naphthyl benzoate

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

12 mg/L

Based on:

ThOD/L

Results and discussion

% Degradation

Parameter:

% degradation (CO2 evolution)

Value:

ca. 14

Sampling time:

28 d

Details on results:

not readily biodegradable

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

other: about 14% degradation observed

Conclusions:

The criterion for ready biodegradability (at least 60% degradation within 10 days of biodegradation exceeding 10%) was
not met.

Executive summary:

MONOBENZOATE was tested for its ready biodegradability in the carbon dioxide (C02) evolution test (modified Sturm test) at 31-32 mg per 2 litres, corresponding to 12 mg TOG/l. The study procedure was based on EEC directive 92/69, C.4-C, December 1992, and OECD guideline No. 301 B July 17, 1992. The Theoretical CO2 production (ThC02) of MONOBENZOATE was calculated to be 2.85 mg CO2/mg. The relative degradation values calculated from the measurements performed during the test period revealed 10 and 19% degradation of MONOBENZOATE for A and B respectively. Thus, the criterion for ready biodegradability (at least 60% degradation within 10 days of biodegradation exceeding 10%) was not met. In the toxicity control MONOBENZOATE was found to be not inhibitory. Since all acceptability criteria prescribed by the protocol were met, this study was considered to be valid. In conclusion, MONOBENZOATE was not readily biodegradable under the conditions of the modified Sturm test presently performed.