4-bromobenzonitrile

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1997-01-13 - 1997-01-14

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods

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:

other: DIN 38412 Part L8

Version / remarks:

03-1991

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: NEN-EN-ISO 10712

Version / remarks:

1996

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

4-bromobenzonitrile

EC Number:

210-764-9

EC Name:

4-bromobenzonitrile

Cas Number:

623-00-7

Molecular formula:

C7H4BrN

IUPAC Name:

4-bromobenzonitrile

impurity 1

Reference substance name:

2-bromobenzonitrile

EC Number:

218-045-1

EC Name:

2-bromobenzonitrile

Cas Number:

2042-37-7

Molecular formula:

C7H4BrN

IUPAC Name:

2-bromobenzonitrile

impurity 2

Reference substance name:

3-bromobenzonitrile

EC Number:

230-127-9

EC Name:

3-bromobenzonitrile

Cas Number:

6952-59-6

Molecular formula:

C7H4BrN

IUPAC Name:

3-bromobenzonitrile

impurity 3

Reference substance name:

Benzonitrile

EC Number:

202-855-7

EC Name:

Benzonitrile

Cas Number:

100-47-0

Molecular formula:

C7H5N

IUPAC Name:

benzonitrile

impurity 4

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

Water

Test material form:

solid

Sampling and analysis

Analytical monitoring:

not specified

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

other: Psreudomonas putida

Details on test organisms:

TEST ORGANISM
- Common name:
- Strain:
- Source (laboratory, culture collection):
- Age of inoculum (at test initiation):
- Method of cultivation:

ACCLIMATION
- Acclimation period:
- Culturing media and conditions (same as test or not):
- Any deformed or abnormal cells observed:

Study design

Test type:

static

Water media type:

freshwater

Total exposure duration:

16 h

Test conditions

Test temperature:

23 +/- 1

pH:

7.1 - 7.4

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flasks
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: glas, 100 mL, ./. 40 mL
- Aeration: no
- Type of flow-through (e.g. peristaltic or proportional diluter): na
- Renewal rate of test solution (frequency/flow rate): na
- Initial cells density: FNU/436 nm = 50
- Control end cells density:
- No. of organisms per vessel:
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 10
- No. of vessels per vehicle control (replicates): 0

GROWTH MEDIUM
- Standard medium used: no
- Detailed composition if non-standard medium was used:
Solution I: 10.0 g NaNO3
2.4 g K2HPO4
1.2 g KH2PO4
1.0 g yeast extract
Dissolved in 500 mL water
Silution II: 10.0 g NaNO3
2.4 g K2HPO4
1.2 g KH2PO4
Dissolved in 500 mL water
Solution III: 40.0 g D(+)-glucose monohydrate
Dissolved in 500 mL water
Solution IV: 0.01 g Fe(III)citrate
4.0 g MgSO4 * 7 H2O
Dissolved in 1 L water

test medium: 25 mL I
25 mL III
50 mL IV
made up to 1 L with water

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
tab water purified by reverse osmosis and subsequently passed over activated carbon and ion-exchange cartiges
- Total organic carbon:
- Particulate matter:
- Metals:
- Pesticides:
- Chlorine:
- Alkalinity:
- Ca/mg ratio:
- Conductivity:
- Culture medium different from test medium:
- Intervals of water quality measurement:

OTHER TEST CONDITIONS
- Sterile test conditions:
- Adjustment of pH: 7.1 - 7.4
- Photoperiod:
- Light intensity and quality:
- Salinity (for marine algae):

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: spectrophotometer
- Chlorophyll measurement: na
- Other:

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Justification for using less concentrations than requested by guideline:
- Range finding study na
- Test concentrations (mg/L): 0; 6.3; 12.5; 25; 50; 100; 200
- Results used to determine the conditions for the definitive study:

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

16 h

Dose descriptor:

EC10

Effect conc.:

ca. 57 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Effect concentrations 2

Key result

Duration:

16 h

Dose descriptor:

EC50

Effect conc.:

ca. 135 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Results with reference substance (positive control):

- Results with reference substance valid? yes
- EC50: 22 mg/L
- Other:

Reported statistics and error estimates:

Linear regression

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Based on the result of the test presently performed, the toxicity threshold value (EC10) of 4-Bromobenzonitrile was 57 mg/L. The "Bewertungszahl" is therefore 4.2 (Bewertung wassergefährdender Stoffe, 1989).
The EC50 was calculated to be 135 mg/L.

Executive summary:

4 -Bromobenzonitril was investigated for its ability to inhibit the cell multiplication of the bacteria species Pseudomonas putida according to DIN 38412 Part L 8 (March 1991) and NEN-EN-ISO 10712 (1996).

Suspensions of Speudomonas putida were exposed th concentrations ranging from 6.3 to 200 mg/L 4 -Bromobenzonitrile.

After incubation for 16 h the extinction values of the bacterial cell suspensions were measured. Significant (> 10 %) toxicity was observed at 100 and 200 mg/L.

Based on the result of the test presently performed, the toxicity threshold value (EC₁₀) of 4-Bromobenzonitrile was 57 mg/L. The "Bewertungszahl" (Assessment figure or value for bacterial toxicity) is therefore 4.2 (Bewertung wassergefährdender Stoffe, 1989). The EC₅₀ was calculated to be 135 mg/L.

The EC₅₀ value for the reference substance, 3,5 -dichlorophenol, tested during the same experiment, was 22 mg/L. Since this value was within the eccepted range of 10 - 30 mg/L for the EC₅₀, and the multiplication factor of the bacteria within the test was over 60, it was concluded that the test conditions were optimal and the results obtained were valid.