Dip coating of air purifier ceramic honeycombs with photocatalytic TiO 2 nanoparticles: A case study for occupational exposure.

Autor: Koivisto AJ; National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark. Electronic address: jok@nrcwe.dk., Kling KI; National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark., Fonseca AS; National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark., Bluhme AB; National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark; Technical University of Denmark, Department of Micro- and Nanotechnology, Ørsteds Plads, Building 345B, DK-2800 Kgs. Lyngby, Denmark., Moreman M; TNO, PO Box 360, 3700AJ Zeist, The Netherlands., Yu M; China Jiliang University, Hangzhou, China; Key Laboratory of Aerosol Chemistry and Physics, Chinese Academy of Science, Xi'an, China., Costa AL; CNR-ISTEC, Via Granarolo, 64, 48018 Faenza, RA, Italy., Giovanni B; COLOROBBIA CONSULTING S.r.L., Via Pietramarina 53, 50053, Sovigliana, Vinci, FI, Italy., Ortelli S; CNR-ISTEC, Via Granarolo, 64, 48018 Faenza, RA, Italy., Fransman W; TNO, PO Box 360, 3700AJ Zeist, The Netherlands., Vogel U; National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark., Jensen KA; National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark.
Jazyk: angličtina
Zdroj: The Science of the total environment [Sci Total Environ] 2018 Jul 15; Vol. 630, pp. 1283-1291. Date of Electronic Publication: 2018 Mar 07.
DOI: 10.1016/j.scitotenv.2018.02.316
Abstrakt: Nanoscale TiO 2 (nTiO 2 ) is manufactured in high volumes and is of potential concern in occupational health. Here, we measured workers exposure levels while ceramic honeycombs were dip coated with liquid photoactive nanoparticle suspension and dried with an air blade. The measured nTiO 2 concentration levels were used to assess process specific emission rates using a convolution theorem and to calculate inhalation dose rates of deposited nTiO 2 particles. Dip coating did not result in detectable release of particles but air blade drying released fine-sized TiO 2 and nTiO 2 particles. nTiO 2 was found in pure nTiO 2 agglomerates and as individual particles deposited onto background particles. Total particle emission rates were 420×10 9 min -1 , 1.33×10 9 μm 2 min -1 , and 3.5mgmin -1 respirable mass. During a continued repeated process, the average exposure level was 2.5×10 4 cm -3 , 30.3μm 2 cm -3 , <116μgm -3 for particulate matter. The TiO 2 average exposure level was 4.2μgm -3 , which is well below the maximum recommended exposure limit of 300μgm -3 for nTiO 2 proposed by the US National Institute for Occupational Safety and Health. During an 8-hour exposure, the observed concentrations would result in a lung deposited surface area of 4.3×10 -3 cm 2 g -1 of lung tissue and 13μg of TiO 2 to the trachea-bronchi, and alveolar regions. The dose levels were well below the one hundredth of the no observed effect level (NOEL 1/100 ) of 0.11cm 2 g -1 for granular biodurable particles and a daily no significant risk dose level of 44μgday -1 . These emission rates can be used in a mass flow model to predict the impact of process emissions on personal and environmental exposure levels.
(Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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