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The Multiple Path Particle Dosimetry (MPPD) model is computer software that estimates and visualizes the deposition, clearance, and retention of particles in the respiratory tract systems of humans, rats, and other species. The mathematical model provides a broad spectrum of settings and input options. This research aims to explore the MPPD model concept and determine the deposition fraction (DF), clearance, and retained mass in the human respiratory tract (HRT) based on the geometric mean diameter (GMD) and mass concentration (MC) of particulate matter (PM) emitted during the 3D printing process. We used the real-time air sample data collected during the 8-hour working shift in the 3D printing office. Ultrafine PM deposits mainly in lungs (56%), fine PM mostly deposits in the upper respiratory tract (URT) (41%) and lungs (39%), but coarse PM mostly deposits in the URT (81%). The biggest DF in lower respiratory tract is ultrafine PM (487 μg), the smaller DF is coarse PM (185 μg) and the smallest DF is fine PM (123 μg). The biggest DF in lung for all PM - lower lobes (fine PM - 60%, ultrafine PM, coarse PM - 61%). In a model, where exposure was 5 hours a day, five days a week, during one month, followed by one year of post-exposure period, it was shown that retained mass in the tracheobronchial (TB) region was 1% for ultrafine and coarse PM each, 2% for fine PM, and 55% for all PM in the pulmonary region. The MPPD software is an easily accessible and valuable tool for assessing the impact of PM on the HRT. Particulate matter decreasing in diameter, tend to deposit mostly in the deeper levels of HRT. Tracheobronchial region clearance is more rapid than pulmonary region clearance. Potentially for persons using the 3D-printer regularly the worst health impact could be associated with smaller size of PM, due to tendency deposit mostly in pulmonary region where the clearance rate is slower.

Svina noteikšanas iespējas asinīs ar instrumentālajām analīzes metodēm, izmantojot dažādus paraugu sagatavošanas veidus. Ribkinska L., darba vadītājas Dr. med. Inese Mārtiņsone un Dr. Chem. Agnese Osīte. Maģistra darbs, 45 lappuses, 18 attēli, 12 tabulas, 45 literatūras avoti, 18 pielikumi. Latviešu valodā. Maģistra darbā ir apkopota literatūra par instrumentālajām analīzes metodēm (ETAAS un ICP-MS), paraugu sagatavošanas metodēm un svina toksisko iedarbību uz cilvēka veselību. Eksperimentālajā daļā veikta svina masas koncentrācijas noteikšana asinīs, izmantojot dažādus paraugu sagatavošanas veidus. Paraugu sagatavošanas metodēm veikta to salīdzināšana, kā arī rezultātu pareizības kontrolei izmantotas divas analīzes metodes: ICP-MS un ETAAS. Tika izvērtēts arī svina līmenis nodarbināto asinīs, kuriem darba vidē ir saskarsme ar svinu., Lead determination options in the blood by instrumental analysis methods using different types of sample preparation. Ribkinska L., supervisors Dr. med. Inese Mārtiņsone and Dr. chem. Agnese Osīte. Master`s thesis, 45 pages, 18 figures, 12 tables, 45 literature references, 18 appendices. In Latvian. The literature review of the master’s thesis contains information about instrumental analysis methods (ETAAS and ICP-MS), sample preparation methods, as well as information about lead and its toxic effects on human health. Lead determination in the blood using different types of sample preparation was performed in experimental part. Sample preparation methods were compared and for the accuracy control two methods of analysis: ICP-MS and ETAAS were used. The concentrations of lead were also evaluated in the blood of employees who are exposed to lead at the working environment.