**Abstract**

Trace elements play an essential role in the normal metabolism and physiological functions of living beings. The distribution and concentration of trace elements in the environment results from both anthropogenic and natural origins; this chapter will focus on volcanism as one of the major natural sources of trace elements. In volcanic areas, the emissions and deposits of volcanogenic elements are key factors for geochemical mobility of trace elements and their distribution in the environment and, their effects on animals and human health. Volcanic areas have been associated with increased incidence of several diseases, such as fluorosis or even some types of cancer, leveraging the studies on the potential of this natural phenomenon as a promoter of diseases. As the Azores Archipelago is a volcanic area, with several manifestations of active volcanism, this region presents itself as an ideal study scenario for a multidisciplinary approach on environmental health problems, such as the exposure to toxic and/or deficient levels of trace elements. This chapter will present an integrated approach, describing the occurrence, the monitoring of trace elements and their characterization, the biological role in human body, and the human biomonitoring and health risk assessment, using case studies as examples.

**Keywords:** human health, biomonitoring, risk assessment, volcanism, trace elements
