An overview of methods and instruments for the assessment of occupational exposure to nanoparticles

: In recent years, there has been a dramatic increase in the application of nanotechnology in industries and the number of workers occupied in different processes of research on and construction, production and residue disposal of products containing nanoparticles. Despite this growth, however, there is still a dearth of information on the risk of occupational exposure to these materials. Due to the growing application of nanoparticles in the workplace, selecting suitable sampling and characterization techniques and instruments as well as investigating their efficiency for the evaluation of occupational exposure is very important. The present review study was conducted to introduce the methods and instruments used for evaluating occupational exposure to nanoparticles with an emphasis on the results of the existing literature on methods and instruments of evaluating occupational exposure to nanoparticles and the different contributing factors and conditions through library resources. The results of this study demonstrate that, in spite of the wide application of nanotechnology in the workplace, a reliable, international and standard method for evaluating occupational exposure to nanoparticles is still lacking. This study also shows that occupational exposure to nanoparticles can be evaluated through modern instruments that identify and characterize nanoparticles in terms of their number, mass concentration and surface area. The Scanning Mobility Particle Sizer (SMPS) was the most widely-used instrument for measuring the number and size distribution of particles. The accuracy and precision of the methods and instruments used for evaluating the exposure to nanoparticles can be investigated in future research as a way of establishing a suitable and reliable evaluative standard.