Related Experiment Video
Updated: Jul 16, 2026

Ecotoxicological Method with Marine Bacteria Vibrio anguillarum to Evaluate the Acute Toxicity of Environmental Contaminants
Published on: May 26, 2017
QSARS for acute toxicity of halogenated benzenes to bacteria in natural waters
Guang-Hua Lu1, Chao Wang, Yu-Mei Li
1Key Laboratory for Integrated Regulation and Resources Exploitation on Shallow Lakes, Ministry of Education, College of Environmental Science and Engineering, Hohai University, Nanjing 210098, Jiangsu, China. ghlucc@sina.com
Objective:
To measure the acute toxicity of halogenated benzenes to bacteria in natural waters and to study quantitative relationships between the structure and activity of chemicals.
Methods:
The concentration values causing 50% inhibition of bacteria growth (24h-IC50) were determined according to the bacterial growth inhibition test method. The energy of the lowest unoccupied molecular orbital and the net charge of carbon atom of 20 halogenated benzenes were calculated by the quantum chemical MOPAC program.
Results:
The log1/IC50 values ranged from 4.79 for 2,4-dinitrochlorobenzene to 3.65 for chlorobenzene. A quantitative structure-activity relationship model was derived from the toxicity and structural parameters: log1/IC50 = -0.531(E(LUMO)) + 1.693(Qc) + 0.163(logP) + 3.375. This equation was found to fit well (r2 = 0.860, s = 0.106), and the average percentage error was only 1.98%.
Conclusion:
Halogenated benzenes and alkyl halogenated benzenes are non-polar narcotics, and have hydrophobicity-dependent toxicity. The halogenated phenols and anilines exhibit a higher toxic potency than their hydrophobicity, whereas 2,4-dinitrochlorobenzene is electrophile with the halogen acting as the leaving group.
Related Concept Videos
Reactions at the Benzylic Position: Halogenation
Electrophilic Aromatic Substitution: Chlorination and Bromination of Benzene
Toxicity Testing in Animals
Microbial Bioremediation of Hydrocarbons

