Development and optimisation of quantitative analytical method to determine BTEX in environmental water samples using HPLC-DAD

Abstract

Petroleum contamination of groundwater and waterways is common throughout the world. Among the fuel components, BTEX compounds are most likely to reach the boreholes and pose a gross risk. The present work describes a simple, reliable analytical technique that fulfils the determination of BTEX (benzene, toluene, ethylbenzene, and xylene isomers) in environmental water samples. The procedure was based on the purge of BTEX (a group of volatile organic compounds (VOCs)) from water samples to a specific volume of acetonitrile prior to making the analysis by high performance liquid chromatography equipped with a photo diode array detector. The developed method was optimised using full factorial design, and the resulting optimum parameters were applied in the experiments of validation which confirm method reliability; recovery was between 94 and 106% with a maximum relative bias of 5.9%, relative standard deviation was less than 7.7% (n = 10), and limit of detection varied from 0.18 to 0.6 μg L⁻¹. Various gas chromatographic methods are available for the analysis of VOCs, but the proposed procedure could be a good alternative choice since many of the conventional methods require time and high cost special techniques coupled with the GC instrument. This analytical method was used successfully to measure the concentrations of BTEX in both laboratory spiked samples and environmental water samples.