We formulated the principles of designing bioluminescent enzyme tests for assessing the quality of complex media which consist in providing the maximum sensitivity to potentially toxic chemicals at a minimal impact of uncontaminated complex media. The developed principles served as a basis for designing a new bioluminescent method for an integrated rapid assessment of chemical safety of fruits and vegetables which is based on using the luminescent bacterium enzymes (NAD(P)H:FMN oxidoreductase and luciferase) as a test system.