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Diss Factsheets

Administrative data

Endpoint:
toxicity to microorganisms
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1991-07-29 to 1991-08-02
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Comparable to guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1991
Report date:
1991

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
other: Bringmann G and Kühn R (1977). Z. Wasser Abwasser Forsch. 10, 87-98.
Deviations:
not specified
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
2,2,4(or 2,4,4)-trimethylhexanedinitrile
EC Number:
283-810-9
EC Name:
2,2,4(or 2,4,4)-trimethylhexanedinitrile
Cas Number:
84713-17-7
Molecular formula:
C9H14N2
IUPAC Name:
2,2,4-trimethylhexanedinitrile; 2,4,4-trimethylhexanedinitrile
Details on test material:
- Test substance: 2,2,4(or 2,4,4)-Trimethylhexanedinitrile of Hüls AG.
- Batch No. 080291 1200 of 08 Feb 1991.
- Purity 96.3 %, sample ID 3630/81302.

Sampling and analysis

Analytical monitoring:
no

Test solutions

Vehicle:
no
Details on test solutions:
STOCK AND TEST SOLUTION AND THEIR PREPARATION
- Stock solution: 1500 mg/l in bidistilled water
- Nutrient solutions: According to guideline, no details reported
- Addition of   80 ml stock solution (undiluted / 1:2 / 1:4 / 1:8) or bidistilled water; 5 ml nutrient solution I ; 5 ml nutrient solution II; 10 ml bacteria 
suspension or aqueous NaCl

Test organisms

Test organisms (species):
Pseudomonas putida
Details on inoculum:
- Bacteria suspension: 436 nm extinction adjusted from 0.303 to 0.300  with aqueous NaCl

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
18 h
Remarks on exposure duration:
+/- 1 hour

Test conditions

Test temperature:
25 +- 2 °C
pH:
6.9; not adjusted
Nominal and measured concentrations:
150; 300; 600; 1200 mg/l (nominal)
Details on test conditions:
TEST SYSTEM
- Exposure vessel type: Sterile 250 ml Erlenmeyer flasks with cellulose  plugs
- Number of replicates: 2 independent tests with each
3 replicates per exposure concentration
5 growth controls (no test substance)
4 sterile controls (no test organisms)

TEST PARAMETER: light absorption at 436 nm, related to sterile controls

STATISTICAL METHODS: graphic evaluation
Reference substance (positive control):
no

Results and discussion

Effect concentrations
Duration:
18 h
Dose descriptor:
EC10
Effect conc.:
230 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: extinction / light absorption
Remarks on result:
other: mean value of test 1 and 2

Any other information on results incl. tables

Test 1: EC10 = 195 mg/l
Test 2: EC10 = 265 mg/l

Mean: EC10 = 230 mg/l

Applicant's summary and conclusion

Validity criteria fulfilled:
not specified
Conclusions:
The EC10 (18 hours) was determined as 230 mg/L (mean value) indicating that the test substance does not pose a significant hazard to aquatic
bacteria.
Executive summary:

The effects of 2,2,4(or 2,4,4)-trimethylhexanedinitrile on the growth of the bacteria species Pseudomonas putida were evaluated by Hüls AG (1991) according to a national standard procedure. Five concentrations ranging from 150 to 1200 mg/L were tested over a period of 18 hours. The light absorbtion (extinction) of the test solutions was measured and the percentage inhibion in relation to the sterile controls was calculated. The following endpoint was derived:

EC10 (18 hours): 230 mg/L

The test was assessed as "reliable without restrictions".