3-nitro-p-cresol

Toxicity to microorganisms

Administrative data

Endpoint:

toxicity to microorganisms

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Data source

Reference

Reference 1

Reference Type:

review article or handbook

Title:

Assessing Applicability Domains of Toxicological QSARs: Definition, Confidence in Predicted Values, and the Role of Mechanisms of Action

Author:

Terry W. Schultz, Mark Hewitt, Tatiana I. Netzeva, Mark T. D. Cronin

Year:

2007

Bibliographic source:

QSAR Comb. Sci. 26, 2007, No. 2, 238 – 254

Reference 2

Reference Type:

review article or handbook

Title:

Accurate Prediction of Aquatic Toxicity of Aromatic Compounds Based on Genetic Algorithm and Least Squares Support Vector Machines

Author:

Beilei Lei, Jiazhong Li, Huanxiang Liu and Xiaojun Yao

Year:

2008

Bibliographic source:

QSAR Comb.Sci. 27, 2008, No.7, 850 – 865

Materials and methods

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Automatically generated during migration to IUCLID 6, no data available

IUPAC Name:

Automatically generated during migration to IUCLID 6, no data available

Details on test material:

CAS Number: 2042-14-0
SMILES : c1c(O)ccc(C)c1N(=O)(=O)
CHEM : 3-Nitro-p-cresol
MOL FOR: C7 H7 N1 O3
MOL WT : 153.14

Test organisms

Test organisms (species):

Tetrahymena pyriformis

Results and discussion

Effect concentrations

Dose descriptor:

EC50

Effect conc.:

ca. 27.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Any other information on results incl. tables

Population growth impairment testing with the protozoa, T. pyriformis was conducted following the protocol of T. Wayne Schultz et al. [Schultz, T.W. TETRATOX: Tetrahymena pyriformis population growth impairment endpoint - a surrogate for fish lethality. Toxicol. Mech. Meth. 1997, 7, 4, 289–309.]. This static assay uses population density quantified spectrophotometrically at 540 nm as its endpoint. The test protocol allows for eight to nine cell cycles in controls. The testsubstance was tested separately three times.

For each test, two controls were used to provide a measure of the acceptability by indicating the suitability of the medium

and test conditions as well as a basis for interpreting data from other treatments. The first control had no test substance but was inoculated with T. pyriformis. The other was a blank and had neither test substance nor ciliates.

Each assay consisted of six to ten different concentrations with duplicate flasks at each concentration. Only replicates with control-absorbence values >0.60 but <0.90 were used in the analyses.

Toxic potency was quantified as the 50% Growth Inhibitory Concentration (IGC50). The IGC50 was determined for

the test substance by Probit Analysis using the Statistical Analysis System (SAS) software with the Y-values being absorbencies

normalized as percentage of control and the X-values being toxicant concentrations in mg/L. Toxicity data were converted to mmol/L.

Applicant's summary and conclusion

Executive summary:

A test with Tetrahymena pyriformis according to Population growth impairment assay.

The 50% growth inhibitory concentration (IC50) is determined by Probit Analysis of Statistical Analysis System (SAS). ).

An EC50 of 27.9 mg/L related to the nominal concentration of 3-Nitro-p-cresol was observed.