Fast and simple assessment of surface contamination in operations involving nanomaterials

Abstract

Highlights Surface contamination caused by handling nanomaterials was traced using fluorescently labeled 80-nm silica nanoparticles. Fluorescent silica nanoparticles granted high analytical sensibility, small sizes and high dispersability in aerosol phase. Below 100 ppm of fluorescent nanoparticles added to the aerosol matter allowed exposure assessment in wide contact surfaces. The appropriate illumination revealed the deposition zones, allowing a low-cost procedure for risk assessment tests.The deposition of airborne nanosized matter onto surfaces could pose a potential risk in occupational and environmental scenarios. The incorporation of fluorescent labels, namely fluorescein isotiocyanate (FITC) or tris-1,3-phenanthroline ruthenium (II) chloride (Ru(phen)3Cl2), into spherical 80-nm silica nanoparticles allowed the detection after the illumination with LED light of suitable wavelength (365 or 405 nm respectively). Monodisperse nanoparticle aerosols from fluorescently labeled nanoparticles were produced under safe conditions using powder generators and the deposition was tested into different surfaces and filtering media. The contamination of gloves and work surfaces that was demonstrated by sampling and SEM analysis becomes immediately clear under laser or LED illumination. Furthermore, nanoparticle aerosols of about 10 5 nanoparticles/cm 3 were alternatively fed through a glass pipe and personal protective masks to identify the presence of trapped nanoparticles at under 405 nm or 365 nm LED light. This testing procedure allowed a fast and reliable estimation of the contamination of surfaces with nanosized matter, with a limit of detection based on the fluorescence emission of the accumulated solid nanoparticles of 40 ng of Ru(phen)3@SiO2 of silica per mg of nonfluorescent matter.

Engineered Nanoparticle Release from Personal Protective Clothing: Implications for Inhalation Exposure

“…The nanotechnology market is expected to grow 17% annually up to 2024, leading to the production of a variety of products using nanomaterials. The development of new applications with nanomaterials gives rise to risks and uncertainties regarding the exposure and adverse effects to human health and the environment . One main concern with the growth of nanotechnology is the protection of frontline researchers in laboratories and workers in production facilities from exposure to engineered nanoparticles (ENPs) through inhalation or skin contact.…”

“…The development of new applications with nanomaterials gives rise to risks and uncertainties regarding the exposure and adverse effects to human health and the environment. 2 One main concern with the growth of nanotechnology is the protection of frontline researchers in laboratories and workers in production facilities from exposure to engineered nanoparticles (ENPs) through inhalation or skin contact. Workers wearing contaminated clothing are at high risk of inhaling ENPs resuspended from clothing without any awareness of the potential danger.…”

Contact transfer of engineered nanomaterials in the workplace

“…A quantitative analysis of the secondary spill images like the one performed by Clemente et al . [13] is beyond the scope of the current work. This image analysis approach would not be feasible for the direct evaluation of workplace surfaces due to the variety of optical properties of potential substrates.…”

“…If the engineered nanomaterials are not fluorescent, additional techniques specific to the properties of the target engineered nanomaterials could be used. Non-fluorescent engineered nanomaterials can be tagged with fluorescent species for tracking purposes, as suggested by Clemente et al [13]. Work practices and risk assessment models may need to be revised in the light of the contact transfer of engineered nanomaterials.…”

“…The generation of aerosols containing engineered nanomaterials has been found to be an important propagation pathway in the workplace, and inhalation is the most studied exposure route [8,11]. Recently, Clemente et al used fluorescent engineered nanomaterials to demonstrate how these materials can propagate through the air during common workplace practices like pouring powders [13]. Contact transfer is another potential pathway for engineered nanomaterial propagation in the workplace.…”