Butanenitrile, 2-amino-2,3-dimethyl-

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: EPA 600/9-78-016/OTS/ASTM

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2-amino-2,3-dimethylbutanenitrile

Cas Number:

13893-53-3

Molecular formula:

C6H12N2

IUPAC Name:

2-amino-2,3-dimethylbutanenitrile

Sampling and analysis

Analytical monitoring:

not specified

Test solutions

Vehicle:

no

Details on test solutions:

- Test concentrations were prepared by preparing a stock solution in deionized water and serially diluting to obtain desired concentration.

Test organisms

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Nominal and measured concentrations:

- Based on the results of the range-finder, test concentrations (nominal) were set at 0, 0.01, 0.1, 0.5, 1.0, and 10 mg/L.

Details on test conditions:

- Temperature and light readings were measured throughout the test and were within acceptable limits.
- The static algal toxicity study on Selenastrum capricornutum was conducted in 250 mL Erlenmeyer flasks containing 100 mL of synthetic algal nutrient medium.
- The deionized water was filtered through a millipore Milli-Q water purification system.
- After the media was prepared, the pH was adjusted to 7.5 and filter-sterilized through a 0.45 um filter.
- To each flask was added 1 mL of algal inoculum containing 2 ×106 ± 10 % cells.
- The test vessels were incubated for 96 hours at 24 ± 2°C under continuous "cool white" fluorescent light and constant shaking.
- Temperature and light intensity were monitored throughout the study.
- Log phase growth was confirmed at 96-hours with a count of 6.9 x 105 cells/ml in the control.
- A 96-hour range finding study was conducted to determine the concentration range for the definitive study.
- Test flasks were prepared in triplicate for each test concentrations and the control.
- Gravimetric determinations of algal growth at each test concentration (0, 0.01, 0.1, 0.5, 1.0, and 10 mg/L) indicated percent effected as 7, 7, 7, 58, 95, and 100, respective to the concentrations tested.
- Statistical analysis of the concentration vs. effect data was obtained by employing a computerized LC50 program.
- This program calculated the LC50 statistic and its 95% C.L. using the moving average test.
- The method of calculation selected for use was that which gave the narrowest confidence limits for the LC50.
- The no effect level was determined by using ANOVA and a multiple means comparison test (Fisher’s LSD).

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

0.36 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate