Benzeneacetic acid, 4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-oxobutyl]-.alpha.,.alpha.-dimethyl-, ethyl ester

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Start of experimental part: September 24, 1997 / End of experimental part: September 24; 1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study according to international guideline

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.11 (Biodegradation: Activated Sludge Respiration Inhibition Test)

Test guideline 3

Qualifier:

according to guideline

Guideline:

ISO 8192 (Water quality - Test for inhibition of oxygen consumption by activated sludge for carbonaceous and ammonium oxidation)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

4-[4-[4-(Hydroxydiphenylmethyl)-1-piperidinyl]-1-oxobutyl]-α,α-dimethyl-ethyl ester benzeneacetic acid

EC Number:

616-391-1

Cas Number:

76812-02-7

Molecular formula:

C34 H41 N O4

IUPAC Name:

4-[4-[4-(Hydroxydiphenylmethyl)-1-piperidinyl]-1-oxobutyl]-α,α-dimethyl-ethyl ester benzeneacetic acid

Constituent 2

Reference substance name:

4-(4-(4-Hydroxydiphenylmethyl)-1-piperidinyl)-1-oxobutyl- alpha,alphadimethylbenzeneacetic acid ethyl ester

IUPAC Name:

4-(4-(4-Hydroxydiphenylmethyl)-1-piperidinyl)-1-oxobutyl- alpha,alphadimethylbenzeneacetic acid ethyl ester

Details on test material:

Name: Fexofenadonethylester
Synonym: Terfenadonethylester
Exact characterization: 4-[4-[4-hydroxydiphenylmethyl]-1-piperidinyl]-1-oxobutyl]-a,a-dimethylbenzeneacetic acid ethyl ester
Code: HOE CG 0529 0Y ZD99 0001
Batch: TAM40-96-13 of August 27, 1996
Solubility in water: not soluble
Analytical certificate of : August 19, 1997
Expiry date: August 27, 1998
Purity (tested batch): 98.65% (w/w)
Impurities: Azacyclonol [115-46-8], p-Cyclopropylketon [169280-10-8]
Stability in water solution: 96 h (information by the sponsor)
Date of delivery (test substance): August 28, 1997

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

activated sludge, domestic

Details on inoculum:

Origin: Sewage treatment plant at Frankfurt am Main-Sindlingen
Type of inoculum: Domestic activated sludge
Preparation of the suspension: sediment from activated sewage sludge was washed three times by centrifuging and resuspending in water with 0.9 %NaCl.
Amount used: 450 ml/l sludge suspension
Content of suspended solids: 23.8 g/l (centrifuged wet matter)
Content of suspended solids: 3.56 g/l (dry matter)
Content in the final test volume: 1.6 g/l (dry matter)
Pretreatment: corresponding to the cited test guideline.
State of acclimatization: not pre-adapted to the test substance or the reference substance.
Storage: The concentrated inoculum suspension was aerated over 2 days. Nutrition solution was added during this period, as mentioned in the test guideline.

Study design

Water media type:

freshwater

Total exposure duration:

3 h

Test conditions

Test temperature:

The incubation temperature was controlled at 19.4°C to 20.2°C.

pH:

8.0-8.4 after the incubation of the test batches.

Nominal and measured concentrations:

Nominal: Test concentration: 1000 mg/l

Details on test conditions:

Technical equipment
Incubation vessels : Glasbottles with a diameter of 60 mm and a grounded neck (NS 29), height 170 mm and a total volume of approx.480 ml.
Test volume : 200 ml each batch
Temperature control : The temperature control was performed by a water circulating thermostate.
Aeration rate/test vessel : 50 litres per hour, only during the incubation period.
Oxygen measurements : With oxygen electrodes, connected to oximeters and two-channel recorders.
Monitoring : During the measuring period the oxygen concentration curves were plotted by the recorders.
Respiration rate : The slope of the linear of the respiration curves accorded to the corresponding respiration rates.
Measurements of the pH : pH-meters

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol in the concentrations of 5, 20 and 30 mg/l

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

3 h

Dose descriptor:

other: EC20

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Effect concentrations 2

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Effect concentrations 3

Duration:

3 h

Dose descriptor:

other: EC80

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Results with reference substance (positive control):

The EC50 of the reference substance 3,5-Dichlorophenol was between 5 mg/l and 30 mg/ and amounted to 15 mg/l. The range of confidence was 8 to 25 mg/l, P=95%.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The EC50 of Fexofenadonethylester to activated sludge (domestic sewage treatment plant) is higher than 1000 mg/l, which was the highest concentration in the test.