Registration Dossier

Administrative data

Endpoint:
short-term toxicity to fish
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2000-08-23 until 2000-12-08
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline-conform study under GLP without restrictions.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2000
Report Date:
2000

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 203 (Fish, Acute Toxicity Test)
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material : BMDBM: butyl methoxydibenzoylmethane
- Substance type: organic mono constituent
- Physical state: White to pale yellow powder

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
- Concentrations: 0 - 100 mg/l
- Sampling method: During the study samples were taken from the blank-control and the filtered and unfiltered solutions prepared at 100 mg/l for analysis.
Sampling:
Frequency At t= 0 h, t = 24 h, and t= 96 h.
Volume 10 ml from the approximate centre of the test vessels.
- Sample storage conditions before analysis: Samples were stored in a freezer until analysis.

Test solutions

Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Preparation started with three solutions containing a loading of 100 mg/I. These three solutions were stirred for 3 days in the dark. Two of the resulting suspensions were then filtered through a paper filter (5 µm) to remove the fraction of non-dissolved test substance particles. The other suspension was not filtered and was used as such. Preparation was performed in the dark as much as possible.
- Differential loading: 100 mg/I and 0.1, 1.0, 10 and 100% of a filtrate prepared from 100 mg/I.
- Controls: Test medium without test substance or other additives (0 mg/I).
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): not applicable
- Concentration of vehicle in test medium (stock solution and final test solution): not applicable
- Evidence of undissolved material (e.g. precipitate, surface film, etc): Deposits and a film were observed at test item concentration 100 mg/l (unfiltered)

Test organisms

Test organisms (species):
Cyprinus carpio
Details on test organisms:
TEST ORGANISM
- Common name: carp
- Strain: Cyprinus carpio
- Source: Zodiac, proefacc, “De Haar Vissen”, L.U. Wageningen, the Netherlands
- Age at study initiation (mean and range, SD): no data
- Length at study initiation (length definition, mean, range and SD): 2.27 ±0.13 cm
- Weight at study initiation (mean and range, SD): 0.38 ± 0.20 g
- Method of breeding: no data
- Feeding during test
- Food type: Trouvit
- Amount: no data
- Frequency: daily


ACCLIMATION
- Acclimation period: At least 12 days after delivery.
- Acclimation conditions (same as test or not): same
- Type and amount of food: Trouvit
- Feeding frequency: daily
- Health during acclimation (any mortality observed): no abnormalities reported


QUARANTINE (wild caught)
not applicable

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
96 h
Post exposure observation period:
not applicable

Test conditions

Hardness:
250 mg/I expressed as CaCO3
Test temperature:
20.0 to 21.3 °C
pH:
At 0h: 7.9 - 8.1
At 96h: 7.5 - 7.7
Dissolved oxygen:
At 0h: 8.6 - 9.2
At 96h: 6.7 - 8.2
Salinity:
Not particularly stated, however detailed description of the composition of the ISO Medium is given in the original study report.
Nominal and measured concentrations:
Nominal concentration: 100 mg/l

Measured:
Sampling time: 0 hours
Unflitered sample measured concentration: 17 mg/l
Flitered sample measured concentration: 0.194 mg/l

Sampling time: 96 hours
Unflitered sample measured concentration: 4.93 mg/l
Flitered sample measured concentration: < 0.04 mg/l (= LOD)
Details on test conditions:
TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 6 litres, all-glass
- Aeration: Test solutions were not aerated during the test
- No. of organisms per vessel: 7 or 3 per vessel, resp.
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.57g fish/litre, i.e. 3 fish per 2 litres of test medium or 0.53 g fish/litre, i.e. 7 fish per 5 litres of test medium.


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: prepared in milli-RO water
- Total organic carbon: Not particularly stated, however detailed description of the composition of the ISO Medium is given in the original study report.
- Particulate matter: no data
- Metals: Not particularly stated, however detailed description of the composition of the ISO Medium is given in the original study report. (Ca, Mg, Na, K).
- Alkalinity: Not particularly stated, however detailed description of the composition of the ISO Medium is given in the original study report.
- Ca/Mg ratio: 4.0
- Conductivity: Not particularly stated, however detailed description of the composition of the ISO Medium is given in the original study report.
- Culture medium different from test medium: no
- Intervals of water quality measurement: at 0h, 24 h, and 96 h


OTHER TEST CONDITIONS
- Adjustment of pH: no data
- Photoperiod: Exposure in the dark.
- Light intensity: Protected from light.


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality and other effects


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10
- Range finding study
- Test concentrations: Filtered: 0.1%, 1%, 10%, and 100% of a 100 mg/l test item solution; 100 mg/l test item solution unfiltered
- Results used to determine the conditions for the definitive study: As expected, analysis of the samples taken from the unfiltered test solution showed that the concentration measured in the water phase decreased from 17.0 to 2.5 mg/I during the first 24-hour test period due to precipitation and deposition of the undissolved test substance particles. The measured concentration after 96 hours was 4.9 mg/I. The concentration measured in the filtered test solution decreased from 0.19 mg/I to a value below the limit of detection, i.e. below 0.04 mg/I during the test period. This decrease in test concentrations could not be prevented and was a consequence of the extremely low water solubility of butyl methoxydibenzoylmethane, i.e. 3 µg/I.
Reference substance (positive control):
yes
Remarks:
pentachlorophenol

Results and discussion

Effect concentrationsopen allclose all
Duration:
96 h
Dose descriptor:
LC50
Effect conc.:
> 0.03 mg/L
Nominal / measured:
nominal
Conc. based on:
dissolved
Basis for effect:
mortality
Remarks on result:
other: 5 µm filtered test solution prepared at a nominal loading of 100 mg/I; the measured concentration measured in the test medium was below the detection limit of 0.04 mg/L. Max. water solubility was determined to be 0.03 mg/l (endpoint water solubility).
Duration:
96 h
Dose descriptor:
NOEC
Effect conc.:
>= 0.03 mg/L
Nominal / measured:
nominal
Conc. based on:
dissolved
Basis for effect:
mortality
Remarks on result:
other: 5 µm filtered test solution prepared at a nominal loading of 100 mg/I; the measured oncentration measured in the test medium was below the the detection limit of 0.04 mg/I; Max. water solubility reported to be 0.03 mg/l.
Duration:
96 h
Dose descriptor:
LL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality
Remarks on result:
other: WAF: 5 µm filtered test solution prepared at a nominal loading of 100 mg/L, the regulatory limit concentration.
Duration:
96 h
Dose descriptor:
NOELR
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality
Remarks on result:
other: WAF: 5 µm filtered test solution prepared at a nominal loading of 100 mg/L, the regulatory limit concentration.
Details on results:
- Behavioural abnormalities: none reported
- Observations on body length and weight: none reported
- Other biological observations: None reported
- Mortality of control: 0
- Other adverse effects control: none reported
- Abnormal responses: none reported
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: Owing to the extremely low solubility of butyl methoxydibenzoylmethane in water, actual concentrations in both the filtered and unfiltered solution could not be maintained at more than 80% of the initial concentration. However, every possible effort was made to ensure that the maximum soluble fraction of butyl methoxydibenzoylmethane was tested and maintained (continuous stirring for three days of a supersaturated 100 mg/I solution followed by filtration). Further, the measured concentration in the unfiltered solution at the end of the test period was still far above the water solubility (3 µg/I).
- Effect concentrations exceeding solubility of substance in test medium:Yes. Nominal concentration 100 mg/l. Water solubility reported to be 3 µg/l only.
Results with reference substance (positive control):
- Results with reference substance valid? yes
- Mortality: Incidence of mortality observed in the reference study
- LC50: The 96h-LC50 for carp exposed to PCP was already reached after 48 hours of exposure and was 0.14 mg/I with a 95% confidence interval between 0.13 and 0.18 mg/I.
Reported statistics and error estimates:
no statistics applied

Any other information on results incl. tables

Table 2: Incidence of mortality in the combined limit/range-finding test:

 Test group  Measured concentrations (mg/l)

Response at 96 h

Number 

Response at 96 h      

 Blank control n.d.   0 0       
   0.1%  filtrate  n.m.   0     0   
   1%  filtrate  n.m.   0  0      
  10%  filtrate   n.m.  0     0
 100% filtrate   0.19 - <0.04  0 *     0

  100 mg/l

 17 - 2.5 

0 * 

 0

n.d. not detected

 n.m. not measured

* Deposits and a film were observed.

Initial number of fish in blank control and 100 mg/l batches: 7 each

Initial number of fish in 0.1%, 1% and 10% batches: 3 each

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
Due to low solubility of test item, actual concentrations could not be maintained at more than 80% of the initial concentration. However, every possible effort was made to ensure that the maximum soluble fraction of the test item was tested and maintained
Conclusions:
Owing to the extremely low solubility of butyl methoxydibenzoylmethane in water, concentration levels toxic for fish could not be reached. Therefore, the 96h-LC50 for Carp exceeded the maximum solubility of butyl methoxydibenzoylmethane in water at a loading of 100 mg/I, the regulatory limit concentration (water solubility of butyl methoxydibenzoylmethane was determined to be ca. 0.03 mg/l).
Executive summary:

96-Hour Acute Toxicity Study in Carp with butyl methoxydibenzoylmethane. The study procedures described in this report were based on the EEC directive 92/69, Part C.1. “Acute toxicity for fish”; and the OECD guideline No. 203: “Fish Acute Toxicity Test”.

Butyl methoxydibenzoylmethane induced no mortality in Carp when exposed to a filtered or an unfiltered solution prepared at 100 mg/I.

Due to low solubility of test item, actual concentrations could not be maintained at more than 80% of the initial concentration. However, every possible effort was made to ensure that the maximum soluble fraction of the test item was tested and maintained. In conclusion, owing to the extremely low solubility of butyl methoxydibenzoylmethane in water, concentration levels toxic for fish could not be reached. Therefore, the 96h-LC50 for Carp exceeded the maximum solubility of butyl methoxydibenzoylmethane in water at a loading of 100 mg/l (nominal), the regulatory limit concentration. The water solubility of butyl methoxydibenzoylmethane was determined to be 0.03 mg/l.