For exposure and risk assessment in occupational settings involving engineered nanomaterials (ENMs), it is important to understand the mechanisms of release and how they are influenced by the ENM, the matrix material, and process characteristics. This review summarizes studies providing ENM release information in occupational settings, during different industrial activities and using various nanomaterials. It also assesses the contextual information - such as the amounts of materials handled, protective measures, and measurement strategies - to understand which release scenarios can result in exposure. High-energy processes such as synthesis, spraying, and machining were associated with the release of large numbers of predominantly small-sized particles. Low-energy processes, including laboratory handling, cleaning, and industrial bagging activities, usually resulted in slight or moderate releases of relatively large agglomerates. The present analysis suggests that process-based release potential can be ranked, thus helping to prioritize release assessments, which is useful for tiered exposure assessment approaches and for guiding the implementation of workplace safety strategies. The contextual information provided in the literature was often insufficient to directly link release to exposure. The studies that did allow an analysis suggested that significant worker exposure might mainly occur when engineering safeguards and personal protection strategies were not carried out as recommended.

The purpose of this research was to investigate whether silver nanoparticles (AgNPs) misting could be an effective disinfection and protection method for cotton fabric. The study showed that the disinfection resulted in the reduction of microorganism number by 32-100%, depending on the strain. Fabric humidity of not less than 84% ensures high effectiveness of the process. It was proved that vegetative cells are more susceptible to nanoparticles than spores. The antimicrobial protection of cotton fabric results in the 33-93% reduction of microorganism number. The application of AgNPs does not influence significantly the optical and mechanical parameters of cotton fabric, even after accelerated light ageing. The AgNPs misting is safe for personnel. The AgNPs misting can be considered as an alternative for currently used disinfection methods of ancient textiles.

Objectives: Diesel exhaust fumes emission is a significant source of ultrafine particles, the size of which is expressed in nanometers. People occupationally exposed to diesel exhaust particles include mainly workers servicing vehicles with engines of this type. This article presents the analysis of measurements of ultrafine particle concentrations occurring in the bus depot premises during the work connected with everyday technical servicing of buses. Material and Methods: The measurements were carried out in the everyday servicing (ES) room of the bus depot before, during and after the work connected with bus servicing. Determinations included: particle concentrations in terms of particle number and particle surface area, and mass concentrations of aerosol. Results: Mean value of number concentration of 10-to 1000-nm particles increased almost 20-fold, from 7600 particles/cm 3 before starting bus servicing procedures to 130 000 particles/cm 3 during the bus servicing procedures in the room. During the procedures, the mean surface area concentration of particles potentially deposited in the alveolar (A) region was almost 3 times higher than that of the particles depositing in the tracheo-bronchial (TB) region: 356.46 μm 2 /cm 3 vs. 95.97 μm 2 /cm 3 , respectively. The mass concentration of the fraction of particulate matter with aerodynamic diameter 0.02-1 μm (PM 1 ) increased 5-fold during the analyzed procedures and was 0.042 mg/m 3 before, and 0.298 mg/m 3 while the procedures continued. Conclusions: At the time when bus servicing procedures continued in the ES room, a very high increase in all parameters of the analyzed particles was observed. The diesel exhaust particles exhibit a very high degree of fragmentation and, while their number is very high and their surface area is very large, their mass concentration is relatively low. The above findings confirm that ultrafine particles found in diesel exhaust fumes may be harmful to the health of the exposed people, and to their respiratory tract in particular.

Background: Exposure to fine and ultrafine particles from transport processes is a main consequence of emissions from engines, especially those with self-ignition. The particles released in these processes are a source of occupational and environmental particles exposure. The aim of this study was to assess the fine and nano-sized particles emission degree during work connected with transport and vehicle servicing. Material and Methods: The tests were carried out at 3 workplaces of vehicles service and maintenance (a car repair workshop, a truck service hall, and a bus depot) during 1 work day in each of them. Measurements were performed using the following devices: DISCmini meters, GRIMM 1.109 optical counter and the DustTrak monitor. The number, surface area and mass concentration, and the number size distribution were analyzed. Results: The mean number concentration (DISCmini) increased during the analyzed processes, ranging from 4×104 p/cm 3 to 8×104 p/cm 3 , and the highest concentration was found in the car repair workshop. The particles mean diameters during the processes ranged 31-47 nm, depending on the process. An increase in the surface area concentration value was observed in correlation with the particles number, and its highest concentration (198 m 2 /cm 3 ) was found during work in the car repair workshop. The number size distribution analysis (GRIMM 1.109) showed the maximum value of the number concentration for particles sized 60 nm. The mean mass concentrations increased during the tested processes by approx. 40-70%, as compared to the background. Conclusions: According to the measurement results, all the workplaces under study constituted a source of an increase in all analyzed parameters characterizing emissions of nano-sized particles. Such working environment conditions can be harmful to the exposed workers; therefore, at such workplaces solutions for minimizing workers' exposure, such as fume hoods or respiratory protection, should be used. Med Pr. 2021;72(5)

StreszczenieWstęp: Celem badania była ocena uwalniania do powietrza stanowisk pracy cząstek ultradrobnych podczas przesypu i pakowania sadzy technicznej. Materiał i metody: Ocena obejmowała wyniki pomiarów przeprowadzonych w zakładzie przesypu sadzy technicznej przed rozpoczęciem procesu przesypu, w czasie wykonywania i po zakończeniu procesu. Określono stęże-nie liczbowe cząstek o wymiarach z zakresu 10-1000 nm i 10-100 nm z wykorzystaniem kondensacyjnego licznika cząstek (condensation particle counter -CPC). Do oceny stężenia masowego cząstek użyto monitora stężenia aerozolu w powietrzu DustTrak II DRX aerosol concentration monitor. Oszacowano także stężenie powierzchniowe cząstek potencjalnie odkładających się w rejonie pęcherzykowym (alveolar -A) i tchawiczo-oskrzelowym (tracheo-bronchial -TB) człowieka, korzystając z monitora nanocząstek AeroTrak 9000. Wyniki: Średnie stężenie masowe cząstek podczas procesu było 6-krotnie wyższe w porównaniu z wartością przed jego rozpoczęciem. Zaobserwowano 3-krotny wzrost średniego stężenia liczbowego cząstek 10-1000 nm i czą-stek 10-100 nm podczas wykonywania ww. czynności. Stężenie powierzchniowe cząstek potencjalnie zdeponowanych w rejonie pęcherzykowym (A) i w rejonie tchawiczo-oskrzelowym (TB) wzrosło 4-krotnie. Wnioski: Podczas przesypywania i pakowania sadzy odnotowano istotnie wyższe wartości każdego z analizowanych parametrów charakteryzujących narażenie na cząstki ultradrobne. Med. Pr. 2015;66(3):317-326 Słowa kluczowe: narażenie zawodowe, sadza techniczna, cząstki ultradrobne, stężenie liczbowe cząstek, stężenie powierzchniowe cząstek, pomiary stężenia cząstek Abstract Background: The aim of the project was to assess the exposure of workers to ultrafine particles released during handling and packing of carbon black. The assessment included the results of the measurements performed in a carbon black handling plant before, during, and after work shift. Material and Methods: The number concentration of particles within the dimension range 10-1000 nm and 10-100 nm was assayed by a condensation particle counter (CPC). The mass concentration of particles was determined by a DustTrak II DRX aerosol concentration monitor. The surface area concentration of the particles potentially deposited in the alveolar (A) and tracheo-bronchial (TB) regions was estimated by an AeroTrak 9000 nanoparticle monitor. Results: An average mass concentration of particles during the process was 6-fold higher than that before its start, while a 3-fold increase in the average number concentration of particles within the dimension range 10-1000 nm and 10-100 nm was observed during the process. At the same time a 4-fold increase was found in the surface area concentration of the particles potentially deposited in the A and TB regions. Conclusions: During the process of carbon black handling and packing a significantly higher values of each of the analysed parameters, characterizing the exposure to ultrafine particles, were noted. Med Pr 2015;66(3):317-326