WORKPLACE EXPOSURE CHARACTERISATION AT A TiO2 NANOPARTICLE PRODUCTION SITEMarkus Berges1, Carsten Möhlmann1, Bert Swennen2, Yves van Rompaey2, Patrick Berghmans31BGIA ? BG Institute for Occupational Health and Safety, 53754 Sankt Augustin, GermanyTel: +49-2241-2312673, Fax: +49-2241-2312234, E-mail: Markus.Berges@dguv.de2Umicore Nanomaterials, Kasteelstraat 7, 2250 Olen, BelgiumTel: +32-14-245018, Fax: +32-14-245716, E-mail: Yves.Vanrompaey@umicore.com3VITO ? Flemish institute for technological research, Boeretang 200, 2400 Mol, BelgiumTel: +32-14-335378, Fax: +32-14-32118, E-mail: Patrick.Berghmans@vito.beKeywords: titanium dioxide, nanoparticles, production, sacking, exposureThe assessment of human exposure to nanoparticles needs precise information on the occurrence of nanoparticles at the workplace. As it is not defined which metric is needed for assessing the biological impact, different characteristics must be measured simultaneously [1]. Measurements at different nanoparticle production processes were carried out. They involve the packing processes for TiO2 like bin and bag filling, taking samples from sacked material and a comparison with outside conditions.Parameters measured are the total number concentration for a certain size range below 1µm, the size distribution of the number concentration using a SMPS (TSI model 3080 with long DMA 3081, software AIM V8.0.0.0 with multiple charge and diffusion correction), the total surface concentration (TSI NSAM model 3550), the size distribution of the mass concentration using a low pressure cascade impactor (type Berner, AERAS LPI 25/0.018/2.0, Hauke, Austria), the size distribution of micrometer particles (TSI APS model 3321), and the mass concentrations of respirable and inhalable dust fractions according to EN 481 [2, 3].ResultsAt the bin filling station total number concentrations between 15 000 and up to 133 000 particles per cm³ appeared (range 14-673 nm) with maxima varying between 20 and 30 nm (Fig. 1). The higher concentrations were due to a leak and after closing the leak the concentrations decreased to less than 29 000 particles per cm3 with maxima at 20 nm. Beyond the maxima the particle number concentration decreased steadily with increasing particle diameter up to 20 µm. The total number concentration outside the plant was approximately 13 000 particles per cm³. The inhalable dust concentration at the bin filling station was 0.232 mg/m³, the respirable dust concentration 0.10 mg/m³. Personal dust sampling for a worker in that area, who performed also different tasks, revealed 0.141 mg/m³ respirable dust concentration. On a filter surface mainly aggregates and/or agglomerates besides a few primary particles could be detected using TEM. The primary particle diameters lay between 25 and 100 nm. The main element in these particles was titanium.References[1] ISO/TR 27628:2007, Workplace atmospheres ? Ultrafine, nanoparticle and nano-structured aerosols ? Inhalation exposure characterization and assessment, ISO, Geneva, February 2007[2] EN 481:1993, Workplace atmospheres - size fraction definitions for measurement of airborne particles; CEN 1993[3] CEN/TR 15230, Workplace atmospheres - Guidance for sampling of inhalable, thoracic and respirable aerosol fractions, CEN 2005
