Influence of saw chain type and wood species on the concentration of wood dust in a forestry operation.

This study examines the impact of chainsaw chain type and tree species on the concentration of inhalable wood dust generated during motor-manual harvesting in forested areas. The effects of conducting real-world measurements of inhalable dust within the operator's breathing zone during forestry work are investigated. Two different chain types were evaluated: the commonly used 3/8" pitch chain (conventional chain) and the 0.325" pitch chain. Additionally, measurements were taken for three tree species: beech, oak, and pine (including both live and standing dead trees after a fire). Results showed that, overall, using the conventional 3/8" chain type yielded the highest concentration of wood dust for all three tree species. Notably, the highest wood dust concentration was observed in the burned Pinus brutia cluster, also with the 3/8" chain pitch. These findings emphasize the importance of understanding how chain type and tree species contribute to wood dust levels.

Contrasting nature of aerosols over South Asian cities and its surrounding environment.

Cross-country assessment of aerosol loading was made over several South Asian megacities using multiple high-resolution remote-sensing database to assess how aerosols vary within the city and its suburbs. Parameters sensitive to aerosol optical and microphysical properties were processed over city-core and its surrounding, separated by a buffer zone. Cities across the Indo-Gangetic Plain (IGP; AOD:0.52-0.72) along with Mumbai (0.47) and Bangalore (0.46) denote comparatively high aerosol loading against non-IGP cities. City-core specific AOD was invariably high compared to surrounding, however with varying gradient having robust geographical signature. Exceptions to this general trend were in Kathmandu (ΔAOD:-0.07) and Dhaka (ΔAOD:-0.01) while strong positive AOD gradient was noted in Bangalore (+0.11), Colombo (+0.08) and in Mumbai (+0.07). While all mainland cities exhibited robust intraannual variability, distinction between city-core and its surrounding AOD exhibited varying seasonality. City-specific geometric coefficient of variation indicated insignificant association with mean AOD as opposed to European and American cities. Both pixel-based and city-specific analysis revealed a strong increasing AOD trend with highest magnitude in Varanasi and Bangalore. Aerosol sub-types based on aerosols' sensitivity to UV-absorption and particle size denotes higher relative abundance of carbonaceous smoke aerosols within city-core, without having significant distinction for mineral dusts and urban aerosols.

Assessing the risks associated with indoor and outdoor air quality in relation to the geographic placement of nursing home.

Indoor air quality significantly impacts the well-being and health of elderly residents in nursing homes. This study was conducted to explore the connection between indoor and outdoor PM (Particulate Matter) concentrations in nursing homes and their association with the facilities' location and construction characteristics. The findings revealed that indoor PM2.5 and PM10 concentrations ranged from 0.2 to 124 µg/m3 and 2-188.4 µg/m3, respectively, which were approximately 12.67 and 1.25 times higher than their outdoor counterparts. A strong correlation (P < 0.05) was identified between indoor PM levels and various factors, including proximity to parks, passenger terminals, and gas stations, as well as building attributes such as single-glazed windows, ceramic floor coverings, and the use of radiators. The risk assessment indicated that carcinogenic risk factors were well within acceptable limits for all nursing homes. However, it's important to note that certain PM components, particularly polycyclic aromatic hydrocarbons (PAH), may have long-term adverse effects on the health of nursing home residents. Even though indoor PM levels met the standards established by the U.S. Environmental Protection Agency (USEPA) for particulate matter risk assessments, the study emphasized that even low levels of indoor air pollutants can affect the health and well-being of older adults, particularly considering the increased vulnerability associated with aging. Consequently, the study underscores the importance of nursing home location selection and the regular monitoring of particulate matter concentrations. These measures are essential for enhancing air quality within nursing homes, ultimately contributing to the improved well-being and health of their residents.

Differential Inflammatory Cytokine Elaboration in Serum from Brick Kiln Workers in Bhaktapur, Nepal.

Previous studies involving workers at brick kilns in the Kathmandu Valley of Nepal have investigated chronic exposure to hazardous levels of fine particulate matter (PM2.5) common in ambient and occupational environments. Such exposures are known to cause and/or exacerbate chronic respiratory diseases, including chronic obstructive pulmonary disease (COPD) and asthma. However, there is a paucity of data regarding the status of systemic inflammation observed in exposed workers at brick manufacturing facilities within the country. In the current study, we sought to elucidate systemic inflammatory responses by quantifying the molecular cytokine/chemokine profiles in serum from the study participants. A sample of participants were screened from a kiln in Bhaktapur, Nepal (n = 32; 53% female; mean ± standard deviation: 28.42 ± 11.47 years old) and grouped according to job category. Blood was procured from participants on-site, allowed to clot at room temperature, and centrifuged to obtain total serum. A human cytokine antibody array was used to screen the inflammatory mediators in serum samples from each of the participants. For the current study, four job categories were evaluated with n = 8 for each. Comparisons were generated between a control group of administration workers vs. fire master workers, administration workers vs. green brick hand molders, and administration workers vs. top loaders. We discovered significantly increased concentrations of eotaxin-1, eotaxin-2, GCSF, GM-CSF, IFN-γ, IL-1α, IL-1ß, IL-6, IL-8, TGF-ß1, TNF-α, and TIMP-2 in serum samples from fire master workers vs. administration workers (p < 0.05). Each of these molecules was also significantly elevated in serum from green brick hand molders compared to administration workers (p < 0.05). Further, each molecule in the inflammatory screening with the exception of TIMP-2 was significantly elevated in serum from top loaders compared to administration workers (p < 0.05). With few exceptions, the fire master workers expressed significantly more systemic inflammatory molecular abundance when compared to all other job categories. These results reveal an association between pulmonary exposure to PM2.5 and systemic inflammatory responses likely mediated by cytokine/chemokine elaboration. The additional characterization of a broader array of inflammatory molecules may provide valuable insight into the susceptibility to lung diseases among this population.

Particulate and gaseous air pollutants exceed WHO guideline values and have the potential to damage human health in Faisalabad, Metropolitan, Pakistan.

First-ever measurements of particulate matter (PM2.5, PM10, and TSP) along with gaseous pollutants (CO, NO2, and SO2) were performed from June 2019 to April 2020 in Faisalabad, Metropolitan, Pakistan, to assess their seasonal variations; Summer 2019, Autumn 2019, Winter 2019-2020, and Spring 2020. Pollutant measurements were carried out at 30 locations with a 3-km grid distance from the Sitara Chemical Industry in District Faisalabad to Bhianwala, Sargodha Road, Tehsil Lalian, District Chiniot. ArcGIS 10.8 was used to interpolate pollutant concentrations using the inverse distance weightage method. PM2.5, PM10, and TSP concentrations were highest in summer, and lowest in autumn or winter. CO, NO2, and SO2 concentrations were highest in summer or spring and lowest in winter. Seasonal average NO2 and SO2 concentrations exceeded WHO annual air quality guide values. For all 4 seasons, some sites had better air quality than others. Even in these cleaner sites air quality index (AQI) was unhealthy for sensitive groups and the less good sites showed Very critical AQI (> 500). Dust-bound carbon and sulfur contents were higher in spring (64 mg g-1) and summer (1.17 mg g-1) and lower in autumn (55 mg g-1) and winter (1.08 mg g-1). Venous blood analysis of 20 individuals showed cadmium and lead concentrations higher than WHO permissible limits. Those individuals exposed to direct roadside pollution for longer periods because of their occupation tended to show higher Pb and Cd blood concentrations. It is concluded that air quality along the roadside is extremely poor and potentially damaging to the health of exposed workers.

Microplastic presence in dog and human testis and its potential association with sperm count and weights of testis and epididymis.

The ubiquitous existence of microplastics and nanoplastics raises concerns about their potential impact on the human reproductive system. Limited data exists on microplastics within the human reproductive system and their potential consequences on sperm quality. Our objectives were to quantify and characterize the prevalence and composition of microplastics within both canine and human testes and investigate potential associations with the sperm count, and weights of testis and epididymis. Using advanced sensitive pyrolysis-gas chromatography/mass spectrometry, we quantified 12 types of microplastics within 47 canine and 23 human testes. Data on reproductive organ weights, and sperm count in dogs were collected. Statistical analyses, including descriptive analysis, correlational analysis, and multivariate linear regression analyses were applied to investigate the association of microplastics with reproductive functions. Our study revealed the presence of microplastics in all canine and human testes, with significant inter-individual variability. Mean total microplastic levels were 122.63 µg/g in dogs and 328.44 µg/g in humans. Both humans and canines exhibit relatively similar proportions of the major polymer types, with PE being dominant. Furthermore, a negative correlation between specific polymers such as PVC and PET and the normalized weight of the testis was observed. These findings highlight the pervasive presence of microplastics in the male reproductive system in both canine and human testes, with potential consequences on male fertility.

Tetrabromobisphenol-A/S and their derivatives in surface particulates from workshop floors of three representative e-waste recycling sites in China.

Surface particulates collected from the workshop floors of three major e-waste recycling sites (Taizhou, Qingyuan, and Guiyu) in China were analyzed for tetrabromobisphenol A/S (TBBPA/S) and their derivatives to investigate the environmental pollution caused by e-waste recycling activities. Mean concentrations of total TBBPA/S analogs in surface particulates were 31,471-116,059 ng/g dry weight (dw). TBBPA, TBBPA-BGE, and TBBPA-BDBPE were the most frequently detected in particulates with average concentration ranges of 17,929-78,406, 5601-15,842, and 5929-21,383 ng/g dw, respectively. Meanwhile, TBBPA, TBBPA-BGE, and TBBPA-BDBPE were the most abundant TBBPA/S analogs, accounting for around 96% of the total. The composition profiles of TBBPA/S analogs differed significantly among three e-waste sites. Similarly, principal component analysis uncovered different pollution patterns among different sites. The discrepancy in the profiles of TBBPA/S analogs largely relied on the e-waste types recycled in different areas. E-waste recycling led to the release of TBBPA/S analogs, and TBBPA/S analogs produced differentiation during migration from source (surface particulates) to nearby soil. More researches are necessary to find a definite relationship between pollution status and e-waste types and study differentiation behavior of TBBPA/S analogs in migration and diffusion from source to environmental medium.

Measurement of the Optical Constants of Sand Samples Using Ellipsometry on Sand-Adhesive Composites.

In order to model the propagation of light through a sand cloud, it is critical to have accurate data for the optical constants of the sand particles that comprise it. The same holds true for modeling propagation through particles of any type suspended in a medium. Few methods exist, however, to measure these quantities with high accuracy. In this paper, a characterization method based on spectroscopic ellipsometry (SE) that can be applied to a particulate material is presented. In this method, a polished disc of an adhesive compound is prepared, and its optical constants are measured. Next, a mixture of the adhesive and a sand sample is prepared and processed into a polished disc, and SE is performed. By treating the mixture as a Bruggeman effective medium, the optical constants of the particulate material are extracted. For verification of the proposed method, it is first applied to pure silica powder, demonstrating good agreement between measured optical constants and literature values. It is then applied to Arizona road dust, a standard reference material, as well as real desert sand samples. The resulting optical constant data is input into a rigorous scattering model to predict extinction coefficients for various types of sand. Modeling results are compared to spectroscopic measurements on static sand samples, demonstrating good agreement between predicted and measured spectral properties including the presence of a Christiansen feature near a wavelength of 8 µm.

Analytical methods for determining environmental contaminants of concern in water and wastewater.

Control and prevention of environmental pollution have emerged as paramount global concerns. Anthropogenic activities, such as industrial discharges, agricultural runoff, and improper waste disposal, introduce a wide range of contaminants into various ecosystems. These pollutants encompass organic and inorganic compounds, particulates, microorganisms, and disinfection by-products, posing severe threats to human health, ecosystems, and the environment. Effective monitoring methods are indispensable for assessing environmental quality, identifying pollution sources, and implementing remedial measures. This paper suggests that the development and utilization of highly advanced analytical tools are both essential for the analysis of contaminants in water samples, presenting a foundational hypothesis for the review. This paper comprehensively reviews the development and utilization of highly advanced analytical tools which is mandatory for the analysis of contaminants in water samples. Depending on the specific pollutants being studied, the choice of analytical methods widely varies. It also reveals insights into the diverse applications and effectiveness of these methods in assessing water quality and contaminant levels. By emphasizing the critical role of the reviewed monitoring methods, this review seeks to deepen the understanding of pollution challenges and inspire innovative monitoring solutions that contribute to a cleaner and more sustainable global environment.•Urgent global concerns: control and prevention of pollution from diverse sources.•Varied contaminants, diverse methods: comprehensive review of analytical tools.•Inspiring a sustainable future: innovative monitoring for a cleaner environment.

Combination of magnetic field and ultraviolet for fouling control in saline wastewater distribution systems.

Fouling is a significant challenge for recycling and reusing saline wastewaters for industrial, agricultural or municipal applications. In this study, we propose a novel approach of magnetic field (MaF) and ultraviolet (UV) combined application for fouling mitigation. Results showed, combination of MaF and UV (MaF-UV) significantly decreased the content of biofouling and reduced the complexity of microbial networks, compared to UV and MaF alone treatments. This was due to MaF as pretreatment effectively reduced the water turbidity, improve the influent water quality of UV disinfection and increases UV transmittance, eliminating the adverse impacts of UV scattering and shielding, hence increased the inactivation effectiveness of UV disinfection process. MaF assisted UV also reduced the abundance of UV-resistant bacteria and inhibited the risk of bacterial photoreactivation and dark repair. Meanwhile, MaF-UV drastically reduced the contents of precipitates and particulate fouling by accelerating the transformation rate of CaCO3 crystal from compact calcite to loosen hydrated amorphous CaCO3, and enhancing the flocculation process. These findings demonstrated that MaF-UV is an effective anti-fouling strategy, and provide insights for sustainable application of saline wastewaters.

Process for maintaining appropriate air quality in a hospital setting during and following a nearby building implosion.

Air quality in a cancer facility is integral to the success of patient treatment. The organization must be committed to providing a patient care environment free of physical and biological hazards that result from construction and demolition activities. This project intended to safely demolish a derelict building in Texas while minimizing air quality risks and impacts to nearby hospitals and a proximal cancer hospital. Two of the neighboring facilities were less than 18 feet (5.5 m) away from the demolition location. Adjacent facilities included inpatient and outpatient cancer treatment clinics, a large data center, a pediatric hospital complex, and a heart institute. Plans to minimize infection risks and dust for respective facilities were designed before implosion and remained in place until total debris removal. Risk assessments of nearby buildings were completed to determine the appropriate precautions and physical barriers needed. Culturable and non-culturable fungal air samples were collected during implosion to verify the management of outside contaminants. Additionally, continuous particulate and routine sampling for culturable and non-culturable fungi were performed for approximately 7 months after the project demolition. Air sampling results from 32 internal areas indicated that most areas remained at pre-implosion background levels. Areas that experienced elevated particle counts were cleaned and resampled, and baseline values returned to pre-implosion levels within 12 hr. Fungal air sampling results were acceptable based on predetermined infection control guidelines. The building was successfully demolished via implosion with no injuries and minimal damage to nearby facilities. The team learned that an integrated approach to project management that includes all stakeholders is essential to success. Contingency planning should account for all variables; no assumptions should be made. Staffing plans should be reviewed to ensure the sampling strategy developed can be implemented appropriately.

Detection of atmospheric aerosols and terrestrial nanoparticles collected in a populous city in southern Brazil.

The main objective of this study is to analyze hazardous elements in nanoparticles (NPs) (smaller than 100 nm) and ultrafine particles (smaller than 1 µm) in Porto Alegre City, southern Brazil using a self-made passive sampler and Sentinel-3B SYN satellite images in 32 collection points. The Aerosol Optical Thickness proportion (T550) identification was conducted using images of the Sentinel-3B SYN satellite at 634 points sampled in 2019, 2020, 2021, and 2022. Focused ion beam scanning electron microscopy analyses were performed to identify chemical elements present in NPs and ultrafine particles, followed by single-stage cascade impactor to be processed by high-resolution transmission electron microscopy. This process was coupled with energy-dispersive X-ray spectroscopy and later analysis via secondary ion mass spectrometry. Data was acquired from Sentinel-3B SYN images, normalized to a standard mean of 0.83 µg/mg, at moderate spatial resolution (260 m), and modeled in the Sentinel Application Platform (SNAP) software v.8.0. Statistical matrix data was generated in the JASP software (Jeffreys's Amazing Statistics Program) v.0.14.1.0 followed by a K-means cluster analysis. The results demonstrate the presence of between 1 and 100 nm particles of the following chemical elements: Si, Al, K, Mg, P, and Ti. Many people go through these areas daily and may inhale or absorb these elements that can harm human health. In the Sentinel-3B SYN satellite images, the sum of squares in cluster 6 is 168,265 and in cluster 7 a total of 21,583. The use of images from the Sentinel-3B SYN satellite to obtain T550 levels is of great importance as it reveals that atmospheric pollution can move through air currents contaminating large areas on a global scale.

Airborne desert dust in the Northern Adriatic area (Croatia): Different sources.

During the implementation of the INTERREG IT-HR project ECOMOBILITY, whose one of the goals was to estimate the impact of ship emissions on air quality in the port city of Rijeka (Croatia) and Venice (Italy), two particular weekly samples were collected in Rijeka, during the first and the thirteen weeks of sampling, i.e. S01 (16.10.-23.10.2018) and S13 (24.04.-30.04.2019.), respectively. Both samples have similarities regarding species characteristic for desert dust contribution, but HYSPLIT analyses excluded Saharan desert to be the source of the S01 sample. Unlike Saharan dust, this sample had a high contribution of fine and ultrafine particles (>50 % and 9.8 %, respectively), as well as secondary inorganic (sulfates, ammonium) and organic (water soluble organic compounds - WSOC) aerosols. Detailed synoptic situation and HYSPLIT backward trajectories pointed out the Syrian Desert as the source of this collected sample. The same source was proved by MERRA-2 reanalysis of the desert dust emission. Although the Saharan dust episodes, mostly in precipitation, are well known in the Northern Adriatic area, this is the first time to indicate Syrian Desert as a source of airborne particulates. This assumption was confirmed with chemical species characteristic for the Syrian Desert, i.e. higher content of potassium from K- feldspar and phosphates.

Lung toxicity, deposition, and clearance of thermal spray coating particles with different metal profiles after inhalation in rats.

Thermal spray coating is a process in which molten metal is sprayed onto a surface. Little is known about the health effects associated with these aerosols. Sprague-Dawley rats were exposed to aerosols (25 mg/m3 × 4 hr/d × 4 d) generated during thermal spray coating using different consumables [i.e. stainless-steel wire (PMET731), Ni-based wire (PMET885), Zn-based wire (PMET540)]. Control animals received air. Bronchoalveolar lavage was performed at 4 and 30 d post-exposure to assess lung toxicity. The particles were chain-like agglomerates and similar in size (310-378 nm). Inhalation of PMET885 aerosol caused a significant increase in lung injury and inflammation at both time points. Inhalation of PMET540 aerosol caused a slight but significant increase in lung toxicity at 4 but not 30 d. Exposure to PMET731 aerosol had no effect on lung toxicity. Overall, the lung responses were in the order: PMET885≫PMET540 >PMT731. Following a shorter exposure (25 mg/m3 × 4 h/d × 1d), lung burdens of metals from the different aerosols were determined by ICP-AES at 0, 1, 4 and 30 d post-exposure. Zn was cleared from the lungs at the fastest rate with complete clearance by 4 d post-exposure. Ni, Cr, and Mn had similar rates of clearance as nearly half of the deposited metal was cleared by 4 d. A small but significant percentage of each of these metals persisted in the lungs at 30 d. The pulmonary clearance of Fe was difficult to assess because of inherently high levels of Fe in control lungs.

The Cellular Accumulation of Vehicle Exhaust Particulates Changes the Acidic pH Environment of Lysosomes in BEAS-2B Airway Epithelial Cells.

Many people are exposed every day to vehicle exhaust particulates (VEPs), which are thought to be taken up by epithelial cells that are the first barrier in our biological defense. The study aim was to investigate how VEPs are processed in the lysosomal degradation system. BEAS-2B airway epithelial cells easily ingest VEPs and have been shown to accumulate in cells for several days, but no elevated cytotoxicity was observed over that time period. An analysis of 3D images confirmed the presence of VEPs in or near lysosomes, and an accumulation of VEPs resulted in an increase in the normal acidic pH in lysosomes and the extracellular release of the lysosomal enzyme ß-hexosaminidase. Epithelial cells were thought to activate the lysosome-mediated secretion of extracellular vesicles to avoid damage caused by non-degradable foreign substances, such as VEPs, and as a side reaction, the acidic pH environment of the lysosomes could not be maintained.

On the Efficiency of Laser Alloying of Grey Cast Iron with Tungsten and Silicon Carbides.

Cast iron is widely used in engineering production and in the surface alloying of workpieces, which is exploited to improve the properties of the material. Research on cast iron is still valid and needed for the manufacturing processes throughout the product life cycle. In this study, the gray, cast iron GJL 200 laser processing is described based on surface alloying with WC and SiC particulates. SEM analysis and XRD analysis, as well as microhardness testing and tribological behavior studies, were employed. It was revealed that laser alloying with carbide particulates affects structural, mechanical, and operational properties compared to cast iron in its initial state. Most importantly, the right choice of laser processing conditions can increase the wear resistance of the cast iron base. The wear resistance after WC alloying was 4-24 times higher compared to the initial material, while after SiC alloying, it was 2-18 times lower than that of the initial material.

Dasatinib suppresses particulate-induced pyroptosis and acute lung inflammation.

Background: Humans are constantly exposed to various industrial, environmental, and endogenous particulates that result in inflammatory diseases. After being engulfed by immune cells, viz. Macrophages, such particulates lead to phagolysosomal dysfunction, eventually inducing pyroptosis, a form of cell death accompanied by the release of inflammatory mediators, including members of the interleukin (IL)-1 family. Phagolysosomal dysfunction results in the activation of the nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome, an immune complex that induces pyroptosis upon exposure to various external stimuli. However, several particulates induce pyroptosis even if the NLRP3 inflammasome is inhibited; this indicates that such inhibition is not always effective in treating diseases induced by particulates. Therefore, discovery of drugs suppressing particulate-induced NLRP3-independent pyroptosis is warranted. Methods: We screened compounds that inhibit silica particle (SP)-induced cell death and release of IL-1α using RAW264.7 cells, which are incapable of NLRP3 inflammasome formation. The candidates were tested for their ability to suppress particulate-induced pyroptosis and phagolysosomal dysfunction using mouse primary macrophages and alleviate SP-induced NLRP3-independent lung inflammation. Results: Several Src family kinase inhibitors, including dasatinib, effectively suppressed SP-induced cell death and IL-1α release. Furthermore, dasatinib suppressed pyroptosis induced by other particulates but did not suppress that induced by non-particulates, such as adenosine triphosphate. Dasatinib reduced SP-induced phagolysosomal dysfunction without affecting phagocytosis of SPs. Moreover, dasatinib treatment strongly suppressed the increase in IL-1α levels and neutrophil counts in the lungs after intratracheal SP administration. Conclusion: Dasatinib suppresses particulate-induced pyroptosis and can be used to treat relevant inflammatory diseases.

Particulates, unregulated and regulated emissions and catalytic converter efficiency evaluation of methanol (M15) fuelled BS-VI compliant light-duty spark-ignition engine.

Methanol adaptation in the transport sector is being encouraged worldwide. Methanol, a high-octane fuel, is emerging as a strong fuel candidate for powering spark-ignition (SI) engines and it can be indigenously produced from low-value agricultural biomass waste and high-ash coal. This study investigated particulates and unregulated and regulated emissions from M15 (15 % v/v methanol, 82 % v/v gasoline, 3 % v/v propanol) fueled Bharat Stage-VI (BS-VI) 2020 compliant light-duty SI engine equipped with a multipoint port fuel injection system and compared it with baseline gasoline fueled engine. The catalytic conversion efficiency for controlling regulated and unregulated emission species are also discussed for both test fuels. The experimental results showed a reduction in carbonaceous emissions from M15 fueled engine. Hydrocarbons (HC), carbon monoxide (CO) and particulate emissions reduced, while oxides of nitrogen (NOx) emissions were comparable to baseline gasoline-fueled engine. The catalytic conversion of CO emission was higher for M15 but lower for HC and NOx emissions. Various unregulated trace emission components such as formaldehyde, acetaldehyde, methane, ethene and propene reduced with methanol addition to gasoline. Considerable reductions in benzene and toluene trace emissions were observed for M15, but methanol and ethane trace emissions were higher. The catalytic conversion of all unregulated trace emission components was comparable for both test fuels except alcohols, where M15 exhibited increased trace emission values. The study reflected that M15 could easily replace gasoline in BS-VI-compliant light-duty SI transportation engines. However, verification of all regulatory emission compliances, diagnostics and durability compliances need be ascertained before large-scale implemetation.

An evaluation of microcrystalline cellulose attributes affecting compaction-induced pellet coat damage through a multi-faceted analysis.

Pellet coat damage in multi-unit pellet system (MUPS) tablets has previously been studied and addressed with limited success. The effects of lactose filler material attributes on pellet coat damage have been relatively well-studied but a similar understanding of microcrystalline cellulose (MCC) is lacking notwithstanding its high cushioning potential. Hence, the relationships between MCC attributes and pellet coat damage were investigated. Single pellet in minitablets (SPIMs) were used to isolate pellet-filler effects and reveal the under-unexplored impact of risk factors found in MUPS tablets. MUPS tablets and SPIMs were prepared with various grades of MCC and pellets with an ethylcellulose or acrylic coat at various compaction pressures. Subsequently, the extent of pellet coat damage was determined by dissolution test and quantified using two indicators to differentiate the nature of the damage. A multi-faceted analytical approach incorporated linear regression, correlations and a classification and regression tree algorithm and evaluated how MCC attributes, such as flowability, particle size and plastic deformability, exert various influences on the extent of ethylcellulose and acrylic pellet coat damage. This analysis improved the understanding of the different mechanisms by which pellet coat damage to these two polymer types occurs which can help enhance future pellet coat damage mitigation strategies.