6H-Benzofuro[3a,3,2-ef][2]benzazepin-6-one, 1-bromo-4a,5,9,10,11,12-hexahydro-3-methoxy-11-methyl-, (4aR,8aR)-rel-

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2001-11-05 to 2002-01-25

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EU Commission Directive 87/302lEEC

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

439-750-2

EC Name:

-

Cas Number:

183487-56-1

Molecular formula:

Hill formula: C17H19BrClNO3 CAS formula: C17H19BrClNO3

IUPAC Name:

(4aR*,8aR*)-1-bromo-4a,5,9,10,11,12- hexahydro-3-methoxy-11-methyl-6H-ben zofuro[3a,3,2-ef][2]benzazepin-6-one hydrochloride

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: RT002113G3A231
- Expiration date of the lot/batch: 2001-12-01 (retest date)
- Purity test date: no data

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature at about 20°C, away from direct sunlight
- Stability under test conditions: Determined in RCC study 825265
- Solubility and stability of the test substance in the solvent/vehicle: in water 120 g/L (non-GLP, sponsor's information; determined in RCC study 825030)

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: no stock solution could be prepared due to insufficient water solubility. Test item amounts were directly weighed into the test flasks. Then, 284 mL of tap water and 16 mL of synthetic wastewater were added to each flask. The test item was mixed by intense stirring for ten minutes at room temperature. Then, 200 mL of activated sludge inoculum was added. The stirring was kept short because according to the results of a pre-test the test item was not stable in water.
- Controls: two controls (tap water, synthetic wastewater and activated sludge inoculum, without test item) and the reference item 3,5-dichlorophenol (positive control) at nominal concentrations of 5, 16 and 50 mg/L were tested in parallel under otherwise identical test conditions.

Test organisms

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Laboratory culture: predominantly domestic wastewater treatment plant, ARA Ergolz II, Füllinsdorf, Switzerland
- Preparation of inoculum for exposure: washed once with tap water by centrifugation, supernatant liquid phase decanted, homogenized aliquot of final sludge suspension weighed, dried, and ratio wet to dry weight calculated.
- Pretreatment: an aliquot of washed sludge was suspended in tap water at 3 g dw/L, holding 3 days prior to testing, fed daily with 50 mL synthetic wastewater per L, kept at room temperature and continuous aeration.
- Initial biomass concentration: 2.3 g dw/L test medium
- The pH of the activated sludge inoculum was adjusted from 8.4 to 6.9 with a diluted sulfuric acid solution.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Test conditions

Hardness:

not applicable

Test temperature:

21-22°C

pH:

8.0-8.6

Dissolved oxygen:

The concentration of dissolved oxygen did not drop below 2.5 mg/L during the incubation period, and just before measurement of the respiration rates the dissolved oxygen concentrations were at least
7.2 mg/L.

Salinity:

not applicable

Nominal and measured concentrations:

Nominal concentrations: Control, 11, 34, 100, 320, 1000 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 1000 mL glass flasks, 500 mL fill-volume
- Aeration: continuously aerated by intense stirring on magnetic stirrers.
- Number of replicates: 5
- Number of control replicates: 2
- Biomass loading rate: initial loading ca. 2.3 g dw/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: tap water + synthetic wastewater, as prescribed by guidelines

OTHER TEST CONDITIONS
- Adjustment of pH: the pH of the activated sludge inoculum was adjusted from 8.4 to 6.9 with a diluted sulfuric acid solution.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): respiration rate measured after 3 h of exposure (well-mixed sample poured into a BOD flask and not further aerated, dissolved oxygen concentration measured with oxygen electrode (WTW OXI 539 meter, Weilheim, Germany) and continuously recorded for 10-15 min)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: x 3.2
- Range finding study
- Test concentrations: results not shown
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

696 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Remarks on result:

other: 95% C.L.: 398-1902 mg/L

Effect concentrations 2

Key result

Duration:

3 h

Dose descriptor:

NOEC

Effect conc.:

325 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Remarks on result:

other: 47-529

Details on results:

- Effect concentrations exceeding solubility of substance in test medium: no data
- The 3h-EC20 = 375 mg T002113/L (95% CL 77-607 mg T002113/L)
- The 3h-EC80 = 1293 mg T002113/L (95% CL 766-16012 mg T002113/L - The upper CL should be valued critically since the inhibition of the respiratory rate was about 70% at the highest test concentration)

Results with reference substance (positive control):

3-h EC50 = 20 mg/L (95% CI = 3-449 mg/L).
This is within the recommended range of 5-30 mg/L confirming suitability of the activated sludge used.

Reported statistics and error estimates:

The 3-h EC50 values and their 95% confidence intervals were as far as possible calculated by Probit Analysis.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

An activated sludge respiration inhibition test (according OECD guideline 209) with activated sludge from a predominantly domestic wastewater treatment plant resulted in a 3-h EC50 of 696 mg T002113/L. The results of the study can be considered reliable without restriction.