2,2,4(or 2,4,4)-trimethylhexanedinitrile

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:

1988-11-28 to 1988-12-01

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test procedure in accordance with national standard methods with acceptable restrictions: Many details of standard procedure not included in report

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: German Umweltbundesamt draft procedure (1984)

Deviations:

not specified

GLP compliance:

no

Test material

Test material information

Constituent 1

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:

2,2,4 (or 2,4,4)-Trimethylhexanedinitrile of Hüls AG, commercial purity (not quantified); yellow liquor

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

STOCK AND TEST SOLUTION AND THEIR PREPARATION
- Concentration of vehicle/ solvent: 0.5 g test substance/l, no vehicle or solvent

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISMS
- Strain: CHODAT (86.81 SAG)
- Initial cell concentration: approx. 20,000 cells/ml

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Nominal and measured concentrations:

- nominal concentrations: 7.5 / 15 / 30 / 60 / 125 / 250 mg/l
- range finder test with 2.5 / 25 / 250 mg/l

Details on test conditions:

TEST SYSTEM
- Number of replicates: 3

TEST PARAMETER
- measurement of turbidity

Reference substance (positive control):

not specified

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

15.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

91.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 76.4-108.5 mg/L

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC90

Effect conc.:

535.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Any other information on results incl. tables

Concentration   / Effect
  7.5 mg/l      /  3.7 %
 15.0 mg/l      / 13.9 %
 30.0 mg/l      / 17.5 %
 60.0 mg/l      / 38.7 %
125.0 mg/l      / 46.7 %
250.0 mg/l      / 86.1 %

Applicant's summary and conclusion

Validity criteria fulfilled:

not specified

Conclusions:

The ErC50 (72 hours) was determined as 91.1 mg/L indicating that the test subsance may be harmful to algae.

Executive summary:

The effects of 2,2,4(or 2,4,4)-trimethylhexanedinitrile on the growth of Scenedesmus subspicatus were investigated by Hüls AG (1988) over a period of 72 hours according to a draft procedure developed by the German Federal Environment Authority (Umweltbundesamt). Six concentrations ranging from 7.5 to 250 mg/L plus control were tested. The turbidity of the test solutions was measured at daily intervals and the percentag growth inhibition was calculated thereof. The following endpoint was derived:

ErC50 (72 hours, growth rate): 91.1 mg/L (CL: 76.4 - 108.5 mg/L)

The study was assessed as "reliable with restrictions".