## 1 Biomarkers and Human Biomonitoring in Occupational Medicine  
Over the last years, biomarkers have increasingly expanded and become early and specific end points for monitoring cellular responses to various disease states and exposures to drugs and chemical agents [1]. They have enjoyed some success as predictors of health outcomes for a number of clinical diseases, but their application for chemical exposure risk assessments has been more limited. Biomarkers may be classified into markers of exposure, effect, and susceptibility [1]. To be useful in providing linkage to human exposure, biomarkers should be as specific as possible to the exposure agents and highly sensitive, so to detect even low levels of exposure [1; 2; 3; 4]. Assessment methods have to be carried out in the proper biological matrix, employing analytical, reliable, and reproducible lab equipment [1; 2; 3; 4]. Exposure biomarkers may be the exposure agent itself, chemical metabolites, products of the interaction between a chemical and some target molecules, cells, or fractions of them, detected in biological matrixes [1; 2; 3; 4; 5]. An aspect of the occupational medicine is evaluating the health status of workers. People who suffer a mild traumatic brain injury (mTBI) have heterogeneous symptoms and disease trajectories, which make it difficult to precisely assess long-term complications. [PERSON] and colleagues [6], in a study, identified decreased episodic memory, anxiety, more sleep problems, and a higher global DNA methylation ratio in the blood of college students with mTBI histories. Those with multiple injuries further showed a lower processing speed than those with a single injury [6]. Shift work (SW) is associated with alterations in the human biological clock and metabolism. Serum exosomal miR-92a concentration was inversely correlated with brown adipose tissue activity playing a pivotal role in energy balance. [PERSON] et al. [7], in a study, focus on exosomal miR-92a as biomarker of brown adipose metabolism among shift workers. A difference in serum exosomal miR-92a levels was found in shift workers. The lower levels of miR-92a in shift workers were suggestive of a higher brown adipose tissue activity compared with daytime workers. However, the possibility that other physiological and pathological processes may influence miR-92a cannot be ruled out [7]. Biological risk is emerging, but the classic workplaces are often put under the \"magnifying glass\" and the rarer and more particular ones are left out. The pathogenicity of environmental _Pseudomonas aeruginosa_ strains, especially isolates from museums and conservation laboratories, is not widely recognized. [PERSON] and colleagues [8] investigated on the virulence attributes of _P. aeruginosa_ isolated from pre-Columbian textiles were compared to those of a clinical strain. Both genetically identified environmental strains (KP842564 and KP842565) exhibited a high ability to form biofilms on abiotic surfaces and high hemolytic activity. In addition, strain KP842564 was a moderate pyocyanin producer and showed proteolytic properties toward bovine serum albumin, fibrinogen, mucin, and casein. In contrast to the clinical isolate, the environmental strains were susceptible to all the tested antimicrobial agents. This study highlights the need to identify microorganisms which inhabit historic objects, in order to avoid exposure to occupational hazards [8]. Exposure limits for the general population are not always available. [PERSON] et al. [9] evaluate the urinary levels of free 2,5-hexanedione (2,5-HD) in Italian subjects non-occupationally exposed to n-hexane, in order to define background values in non-occupational settings. Results of this investigation highlighted that the urinary levels of free 2,5-HD were in the range of \(<\)12.0-77.9 \(\upmu\)g/L (5 th-95 th percentiles). The urinary excretion of the metabolite did not seem to be influenced by gender, age, smoking habit, or area of residence.