Nanometric particles unintentionally released into the workplace are potentially toxic to workers. They can easily settle in the respiratory system, and are distinctive because of their large specific surface area and high potential for causing pulmonary inflammation.

A new study published by the IRSST characterize unintentionally released nanoparticles (URNPs) found in six workplaces, an underground mine, a truck repair shop, an underground transportation network, a foundry, a machine shop and a wax casting shop, on the basis of a broad range of indicators. 

Concentrations were assessed according to numerical and mass metrics, using an array of direct reading instruments (DRIs). Time-averaged measurements were also taken, based on the type of contaminant specific to each workplace. In parallel, measurements for microscopy characterization were taken in the same six workplaces.

An innovative strategy enabled the research team to characterize the URNPs released in the different workplaces with respect to both number and mass concentrations. Microscopy studies on particle samples from the microscope grid taken with a Mini Particle Sampler^® were used to characterize the particles collected based on their morphology and chemical composition.

Nanoparticles are defined as particles of matter between 1 and 100 nanometres (nm) in diameter. There is a distinction between manufactured nanoparticles (MNPs) and unintentionally released ones (URNPs, also known as ultrafine particles or UFPs). The former are the result of commercial production in the field of nanotechnology, while the latter are natural (e.g. evaporation, erosion, volcanic eruption) or anthropogenic (welding fumes or diesel emissions) in origin.