Publications by authors named "Roberta C Urban"

Article Synopsis
  • The study investigated microplastic (MP) concentrations in the atmosphere at Alvaro Guião School in São Carlos, Brazil, from 2021 to 2022, finding significant levels both outdoors and indoors.
  • The predominant type of MP detected was fragments, with polyester being the top component, and indoor fiber concentrations were notably higher during the dry season due to factors like clothing and ventilation.
  • This research highlights the presence of plastic pollution in environments frequented by children, emphasizing the need for guidelines to assess acceptable levels of microplastics in the air.
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In the context of a rising global temperature, biomass burning represents an increasing risk to human health, due to emissions of highly toxic substances such as polycyclic aromatic hydrocarbon (PAHs). Size-segregated particulate matter (PM) was collected in a region within the sugarcane belt of São Paulo state (Brazil), where biomass burning is still frequent, despite the phasing out of manual harvesting preceded by fire. The median of the total concentration of the 15 PAHs determined was 2.

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Atmospheric Particulate Matter (PM) is a pollutant with diverse origins, exhibiting varying chemical compositions, and undergoes several molecular transformations in the atmosphere. In this study, PM samples (PM, PM and TSP) were collected in five Brazilian cities (Camboriú-SC; Catalão-GO; Florianópolis-SC; Limeira-SP and Novo Hamburgo-RS) during the four seasons of the year. Analysis of Variance (ANOVA) was used to evaluate the differences between each city and season in PM concentration.

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Brazil maintains its position at the top of the global ranking of plastic producers, yet recycling efforts have been incipient. Recent data reveals an annual production of approximately 14 million tons of plastic waste, not accounting for the surge in the usage of plastic masks and related materials due to the COVID-19 pandemic. However, what remains largely unreported is that over half of post-consumer plastic packaging in Brazil is managed without any monitoring, and it remains unclear how this will contribute to the occurrence of plastic waste and microplastics in Brazilian freshwaters.

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The effects of PM on human health were investigated using samples collected in São Carlos city (São Paulo state), by the determination of the concentrations of PAHs and derivatives, together with evaluations of cytotoxicity and the formation of ROS in in vitro tests. In 2016, the mean concentrations of PM, ΣPAHs, Σoxy-PAHs, Σnitro-PAHs, Σsaccharides, and Σions were 21.12 ± 9.

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The present study reports the development of a bioassay using Artemia spp. to analyse the preliminary ecotoxicity of atmospheric aerosols (PM), which can affect the environment and human health. Herein, PM samples were collected in the city of Goiânia (Brazil) in 2016, extracted with ultrapure water and subsequently filtered through membranes with different pore sizes (100, 0.

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In this study, positive matrix factorization method was used for source apportionment of PM in the city of São Carlos from 2015 to 2018. The annual mean concentrations of PM, 15 PAHs, 4 oxy-PAHs, 6 nitro-PAHs, 21 saccharides, and 17 ions in these samples were in the ranges 18.1 ± 6.

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Objectives To determine the concentration of calcium, iron, manganese and zinc ions after the application of chelator to Enterococcus faecalis biofilms. Material and Methods Fifty bovine maxillary central incisors were prepared and inoculated with E. faecalis for 60 days.

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