Propiononitrile

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:

2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Data source

Reference

Reference Type:

publication

Title:

Toxicity and quantitative structure–activity relationships of nitriles based on Pseudokirchneriella subcapitata

Author:

Chun-Pin Huang, Yun-Ju Wang, Chung-Yuan Chen

Year:

2007

Bibliographic source:

Huang, C.P., Wang, Y.J. & Chen, C.Y., 2007. Toxicity and quantitative structure-activity relationships of nitriles based on Pseudokirchneriella subcapitata. Ecotoxicology and Environmental Safety, 67(3), pp.439–446.

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

BOD bottles were filled with algae, medium and toxicants to determine the BOD and algal growth rate over time. This method is more applicable for volatile compounds.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Propiononitrile

EC Number:

203-464-4

EC Name:

Propiononitrile

Cas Number:

107-12-0

Molecular formula:

C3H5N

IUPAC Name:

propanenitrile

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

Twelve compounds including acetonitrile, chloroacetonitrile, dichlor- oacetonitrile, trichloroacetonitrile, bromoacetoitrile, propionitrile, 3- chloropropionitrile, butyronitrile, isobutyronitrile, 4-chlorobutyronitrile, benzonitrile, and malononitrile were tested in this study. The toxicant concentrations presented in this work are in the form of nominal concentration. All chemicals used were of reagent grade and all tests were performed in triplicate. Stock solutions of toxicants were prepared in foil-wrapped glass containers. Toxicants with low solubility were dissolved in acetone solution. Solvent controls were conducted and the results were checked using t-test at P 1⁄4 0:05. Before commencing the experiment, stock solution was freshly prepared and its concentration was analyzed using a total organic carbon (TOC) analyzer.

Test organisms

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: /
- Strain: UTEX 1648
- Source (laboratory, culture collection): not specified
- Age of inoculum (at test initiation): not specified
- Method of cultivation: The alga P. subcapitata (UTEX 1648) was grown in a 4-L transparent chemostat incubator operated under steady state.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Nominal and measured concentrations:

14.93, 59.73, 119.45, 238.91, 358.36 and 716.72 mg/L

Details on test conditions:

Algal inoculum were withdrawn from the chemostat and transferred into 300-mL BOD bottles, together with dilution water (with growth medium) and toxicants. The BOD bottles were completely filled up with no headspace left. Water seal was provided to ensure a closed test environment. The bottles were then placed on an orbital shaker operated at 100 rpm. Temperature and light intensity were kept at 2471 1C and 65 mEm-2s-1 (710%), respectively. US EPA (1996) bottle medium with no EDTA content was used for toxicity testing. The dilution water was stripped by nitrogen gas to reduce the DO level. In addition, the N2 gas contained 0.5% carbon dioxide as an extra carbon source. The DO level at the beginning of the test was approximately 1–3 mg/L. Two response endpoints were used to evaluate the toxicity of toxicants: DO production (DDO) and algal growth rate based on cell density. The median effective concentration (EC50) was defined as the toxicant concentration that reduced the final DO or algal growth rate to half of that obtained by the control. The initial inoculated cell density was 15 000 cells/mL and the duration of the test was 48 h. A detail description of the test method and the concept of experimental design can be found from the author’s previous work (Lin et al., 2005).

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

223.09 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: dissolved oxygen

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

480.26 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Applicant's summary and conclusion

Validity criteria fulfilled:

not specified

Conclusions:

In a toxicity test with BOD bottles, which is more applicable for volatile compounds, the effects of propionitrile on Pseudokirchneriella subcapitata were determined. EC50 values were 223 and 480 mg/L for change in DO and growth rate, respectively.