Twenty-four male industrial workers, exposed to various chromium compounds for 1-17 years (but deprived of overt symptoms of chromium toxicity) were the subjects of our study. The workers’ urine chromium was measured serially by atomic absorption spectrometry. The simple kinetic model was proposed for tracking pre-shift and post-shift as well as day-to-day variation of urine chromium concentrations. This model proved to be useful in determining the biological effects of exposure to chromium compounds. Subsequently, the statistically significant associations of chromium status parameters (as delivered by the kinetic model) with biochemical indices, blood panel parameters, spirometric indices, and oncentrations of tumour markers [carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SC -Ag), cytokeratin 19 fragment (CY FRA 21-1), and neuron-specific enolase (NSE)] in those workers were evaluated by means of the hierarchical partial least squares method (PLS 2 model). These relations should be further studied in larger groups of workers. In several individuals, outlined in the PLS 2 model, cigarette smoking did not constitute any important source of chromium, although seniority at work in the chemical plant did influence biochemical status.