Workplace exposure to nanomaterials

Workers and researchers involved in the manufacturing and handling of nanoparticles and nanomaterials are likely exposed by inhalation, but published information on exposures in the workplace is still sparse. The main reason of this sparseness is that measuring exposure to nanoaerosols is not an easy task. It differs in several ways from traditional aerosols, for which established measurement procedures and techniques exist.   Although some guidance for assessing nanoaerosol exposure has been recently been proposed by published documents like ISO TR/27628 (2006) and ISO TR/12885 (2008), there is still insufficient scientific evidence to decide on which particle size range and health-relevant exposure parameters of nanoaerosol should be measured – size selective number, surface, mass concentration or something else – to characterize exposure, or which are the most appropriate instruments or methods to use. However, there are now international efforts to harmonize the different approaches to characterize emissions and potential exposures.  Here, the current state-of-art and applicable measurement techniques and strategies to characterize exposure to nanoaerosol will be discussed through data obtained during field measurement campaigns, and the measurement requirements for the future considered.  Given the limited amount of information about risks to health that may be associated with nanomaterials, taking measures to minimize worker exposures is prudent. Best practices together with appropriate engineering control techniques should be developed. For most processes and job tasks, the control of airborne exposure to nanoaerosols can be accomplished using a variety of engineering control techniques similar to those used in reducing exposure to general aerosols.