A pilot study was undertaken to characterize the concentration, duration and particle size distribution of the talc cloud that forms in the personal breathing zone (PBZ) during application of certain talc-containing cosmetics. Multiple direct-reading instruments were employed to simultaneously monitor PM concentrations (particulate matter with aerodynamic diameter < 4 µm; mg/m) at different distances from each of three subjects while they applied talc products. Results indicated that the purpose and method of applying the talc product, combined with behavioral and physical differences amongst subjects, all strongly influenced airborne talc concentrations and the duration of the cloud. Air concentrations of talc in the PBZ averaged around 1.0 mg/m, and the duration of exposure varied from less than one minute to more than ten minutes. The real-time monitors captured the occasional formation of secondary clouds, likely caused by resuspension of talc particles from skin or other surfaces. Measurements of aerosolized baby powder, face powder, and two adult body powders indicated that the median aerodynamic diameter of the talc cloud ranged from 1.7 to 2.0 µm. These direct-reading approaches were valuable for providing detailed characterization of short duration exposures to airborne talc particles, and will be useful to support future exposure assessments of talc and other powders in consumer products.
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http://dx.doi.org/10.3390/ijerph16203830 | DOI Listing |
Nano Lett
January 2025
Engineering Research Center of Nano-Geomaterials of Ministry of Education, China University of Geosciences, Wuhan 430074, China.
The crystalline phase of metal oxides is a key determinant of the properties and functions of the nanomaterials. Traditional approaches have focused on replicating bulk-phase structures, with limited exploration of phase diversity due to challenges in controlling the crystal morphology. Here, we introduce a nanoclay-mediated strategy for crystal-phase engineering, using talc to modulate the morphology and phase of manganese oxide (MnOx) nanoparticles.
View Article and Find Full Text PDFEnviron Pollut
January 2025
Department of Geology, Aligarh Muslim University, Aligarh, India.
Evolution of groundwater genesis in Central Ganga Plain (CGP) is scrutinized with due consideration of hydrochemical and hydrodynamic environment within Quaternary alluviums. Wide variation in hydrochemical facies in CGP indicates a dynamic hydro-geochemical environment influenced from the seasonal rainfall, return flows, canal seepages, and anthropogenic activities. The Ca-HCO facies retaining meteoric nature is characterized by shallow water levels, high recharge rate, high hydraulic conductivity, low salinity and trace elemental load.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
School of Basic Education, Beijing Polytechnic College, Beijing 100042, China.
In this study, waterborne polyurethane (WPU), a novel modifier, was used for the wet surface modification of talc, and its mechanism was investigated. Polypropylene (PP)-based composites with modified talc were synthesized and subjected to an examination of their mechanical properties. The wetting contact angle demonstrated that the modified talc exhibited an excellent modification effect at a specific amount of modifier (2.
View Article and Find Full Text PDFPharmaceutics
December 2024
Área de Análisis de Medicamentos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario and Instituto de Química Rosario (IQUIR, CONICET-UNR), Suipacha 531, Rosario S2002LRK, Argentina.
Triclabendazole (TCB) is a well-established anthelmintic effective in treating fascioliasis, a neglected tropical disease. This study employs quality by design (QbD) to investigate the impact of TCB polymorphism and pharmacotechnical variables, from the development of immediate-release tablets to process optimization and green analysis. Critical process parameters (CPPs) and critical material attributes (CMAs), characterized by type of polymorph, composition of excipients (talc, lactose, cornstarch, and magnesium stearate), and compression force, were screened using a Plackett-Burman design (n = 24), identifying polymorphic purity and cornstarch as a CPP.
View Article and Find Full Text PDFEur J Pharm Sci
February 2025
Ss. Cyril and Methodius University in Skopje, Faculty of Pharmacy, Institute of Pharmaceutical Technology, Mother Theresa 47, 1000 Skopje, North Macedonia. Electronic address:
This study leverages Fourier Transform Near-Infrared (FT-NIR) spectroscopy to monitor the coating process of pharmaceutical tablets using PVA-based TiO-free films, with talc and iron oxides as opacifiers. By employing a combination of multivariate analytical techniques, the correlation between film coating progression and film thickness was evaluated. Assessment of coating thickness for different coating levels was performed by optical microscopy.
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