EXPOSURE ASSESSMENT

EXPOSURE ASSESSMENT

Initial forays into assessing exposures to ENMs were largely drawn from particulate matter and asbestos sampling techniques (Kuhlbusch et al. 2004; NIOSH 2009a). Maynard et al., Who examined a single-walled carbon nanotube (SWCNT) generation operation using an SMP analyzer for particle counting and size and filter capture, demonstrated workplace air concentrations of up to 53 µg / m 3 (Maynard et al. 2004).

In 2007, Methner et al. They conducted studies in a carbon nanofiber (CNF) facility using a real-time CPC as well as filter capture, followed by off-line transmission electron microscopy analysis, and found that the highest amount of particulate aerosolization occurred. during the use of the saw (Methner et al. 2007). These studies showed that ENM aerosols were measurable and often tied to specific tasks.

"Weaknesses of the technique"

Studies demonstrated a weakness in the ability to measure exposures in a worker's personal breathing zones,
 as well as the need for a more consistent sampling protocol that could differentiate the background concentrations of incidental non-engineered nanoparticles (such as diesel exhaust material) (Schulte et al, 2000)

APPROACH TO THE BEST CONCLUSIONS IN EXHIBITION ADVICE.

An example of these practices can be seen in the 2012 report by Dahm et al., In which careful decision-making and multiple techniques allowed the research group to demonstrate statistically significant correlations in exposure between elemental carbon levels and exposures to CNT / CNF (Dahm et al. 2012).

This has caused the amount of exposure data available to increase rapidly, and thus the field is becoming more sophisticated. In 2015, two studies were published comparing numerous sampling sites and events to derive high-confidence conclusions (Bekker et al. 2015; Dahm et al. 2015); Bekker et al. they were able to define the task with the greatest exposure in their study. Such a comprehensive sampling strategy, applied consistently and with a multifaceted methodology, represents the future of occupational exposure assessment to nanoparticles.