We demonstrate the use of saline mouth rinse and chemical fingerprinting approach in screening for oral lesions from tobacco product using patients in low-resource settings in rural India. The method is based on the use of a nonspecific long lifetime luminescent lanthanide label, time-resolved measurement and modulator chemistry that is sensitive to ions, proteins and pH but without specific probes. The sensitivity and specificity of the method bases on the use of trained classification algorithms. The overall lesion detection accuracy of the method is shown to be about 90% with the tested patient material utilizing two differently trained classification algorithms.