Development of a detection method based on dielectric spectroscopy for real-time monitoring of meta-cresol contamination in beach-sand

•A microwave based, in-vitro, spectroscopic technique has been developed.•Close-ended transmission line coaxial prototype probe was designed for amplification strategy.•This novel approach was applied to analyse the polarization mechanisms to better understand the electromagnetic characteristics of beach-sand samples.•This probe sensitivity is 0.58%−1 for water and 0.12%−1 for meta-cresol.•This microwave sensor has broad band frequency (10MHz–1GHz) coverage.