Exposure assessment

Workers have the highest chance of being exposed to engineered nanomaterials; therefore, if such materials display hazardous effects, workers might develop adverse health effects upon exposure. In the absence of definitive information about the possible biological risk posed by nanomaterials, evaluation of exposure and implementation of measures avoiding or reducing exposure are mandatory. This chapter discusses the modalities of exposure to nanomaterials in workers according to the specific occupational settings, and to the routes of exposure. Emphasis is placed on the physicochemical modifications, which the nanomaterials may undergo before coming in contact with the biological barriers of the workers (i.e., lung, skin, and the gastrointestinal tract) and how these modifications may translate into different biological outcomes. We highlight some of the challenges in assessing exposure in the workplace including measurement strategies, metrics, and instrumentations. Finally, considerations on the most appropriate health surveillance programs, based on the current, albeit incomplete knowledge of the biological effects of nanomaterials, are discussed.