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Environmental Nanoparticles Reach Human Fetal Brains

LILIAN OFELIA CALDERON GARCIDUEÑAS ANGEL AUGUSTO PEREZ CALATAYUD ANGELICA GONZALEZ MACIEL RAFAEL REYNOSO ROBLES Héctor Gabriel Silva Pereyra Andrea Ramos Morales RICARDO TORRES JARDON Candelario de Jesús Soberanes Cerino Raúl Carrillo Esper JESÚS CARLOS BRIONES GARDUÑO Yazmin del Socorro Conde Gutiérrez (2022, [Artículo])

"Anthropogenic ultrafine particulate matter (UFPM) and industrial and natural nanoparticles (NPs) are ubiquitous. Normal term, preeclamptic, and postconceptional weeks(PCW) 8–15 human placentas and brains from polluted Mexican cities were analyzed by TEM and energy-dispersive X-ray spectroscopy. We documented NPs in maternal erythrocytes, early syncytiotrophoblast, Hofbauer cells, and fetal endothelium (ECs). Fetal ECs exhibited caveolar NP activity and widespread erythroblast contact. Brain ECs displayed micropodial extensions reaching luminal NP-loaded erythroblasts. Neurons and primitive glia displayed nuclear, organelle, and cytoplasmic NPs in both singles and conglomerates. Nanoscale Fe, Ti, and Al alloys, Hg, Cu, Ca, Sn, and Si were detected in placentas and fetal brains. Preeclamptic fetal blood NP vesicles are prospective neonate UFPM exposure biomarkers. NPs are reaching brain tissues at the early developmental PCW 8–15 stage, and NPs in maternal and fetal placental tissue compartments strongly suggests the placental barrier is not limiting the access of environmental NPs. Erythroblasts are the main early NP carriers to fetal tissues. The passage of UFPM/NPs from mothers to fetuses is documented and fingerprinting placental single particle composition could be useful for postnatal risk assessments. Fetal brain combustion and industrial NPs raise medical concerns about prenatal and postnatal health, including neurological and neurodegenerative lifelong consequences."

Environmental medicine Placental impairment Neurodevelopmental disorders Fetal brains Erythroblasts Preeclampsia Nanoparticles NPs extracellular vesicles Petrochemical pollution Villahermosa Tabasco BIOLOGÍA Y QUÍMICA QUÍMICA BIOQUÍMICA BIOQUÍMICA

Sustainable urban mobility: An alternative for air pollution in the Guadalajara Metropolitan Area

José Antonio Olivares Mendoza Clemente Hernandez-Rodriguez Luz Alicia Jimenez Portugal (2023, [Artículo, Artículo])

The objective of this paper is to evaluate whether the low-carbon transport strategy (subway, rapid transit bus system -Macrobús-, trolleybus, and shared bicycles) implemented in the Guadalajara Metropolitan Area (AMG) from 2000 to 2019 improves air quality. Sustainable urban mobility is the movement of people in cities in a way that generates the least impact on the environment. We analyze three actions of government intervention in the same sense. This is the first study for Guadalajara, the third-largest city in Mexico. We use robust Newey-West estimators and endogenously model pollution disruptions using the Bai Perron approach. Our results suggest that this type of public transport reduces SO2, NO2, O3, and CO, though we find an increase in PM10. We also identified that when the service of the first line of the Bus Rapid Transit was consolidated CO, O3 and PM10 decreased. In addition, the improvement in the connectivity of the bus network with the subway means that only NO2 diminished. Finally, the entry into operation of the shared bicycle program reduced PM10, while increasing O3 and in SO2. In short, sustainable urban mobility is an alternative to making the transit of people efficient, while mitigating air pollution in the AMG.

Contaminación del aire Transporte urbano Bicicletas compartidas Autobuses de tránsito rápido Metro CIENCIAS SOCIALES CIENCIAS SOCIALES Air pollution Urban transport Bus Rapid Transit

Las patologías de los recubrimientos en muros y su repercusión en la salud respiratoria de los usuarios

Rosario Tovar (2023, [Tesis de doctorado])

251 páginas. Doctorado en Diseño Bioclimático.

El nivel de calidad del aire interior (CAI) tiene incidencia directa en la salud humana, por eso, es objeto de estudio del diseño bioclimático, toda vez que éste promueve el aprovechamiento de los factores ambientales para la creación y acondicionamiento de espacios en los que los usuarios experimenten confort y bienestar. Además, de impulsar la construcción con sentido común, en donde prevalezca el uso racional de los recursos y una baja dependencia energética. En la presente tesis se pudieron identificar las propiedades de los materiales más comunes que conforman los recubrimientos de muros (cal, cemento, mortero de cemento y yeso) para reconocer los que mejor se adaptan al clima en la Cd. de México, mismos que según se pudo constatar, contribuyen en el control de algunos factores de riesgo (físico: humedad, químico: tóxicos y biológico: microbios) relacionados con una baja calidad del aire al interior de las viviendas. Tal función mitiga o reduce la aparición de algunos de los padecimientos respiratorios más frecuentes en los usuarios como: alergias, asma, rinitis, gripe y sinusitis. Los análisis a los que fueron sometidos los recubrimientos de cuatro materiales ligantes, permitieron evaluar su desempeño ante factores ambientales semi-controlados (temperatura, humedad relativa y concentración de dióxido de carbono) inherentes al funcionamiento del propio espacio interior y al lugar de emplazamiento del mismo. Obviamente, todos los recubrimientos reaccionaron de forma distinta y acorde con las propiedades físicas y químicas de los materiales presentes en cada uno de ellos. Siendo las variaciones más representativas y satisfactorias, las relacionadas con la permeabilidad y el efecto biocida de los recubrimientos hechos con mezcla de cal. Las patologías que mostraron algunos recubrimientos a lo largo del periodo de monitoreo, debido a la insuficiente gestión de la humedad, al alto desarrollo microbiano y a la naturaleza química del material ligante, fueron criptoeflorescencias, moho, bacterias y desprendimiento/diseminación de partículas; mismas que se consideraron definitorias para establecer que al igual que los seres vivos, los materiales de construcción necesitan rangos higrotérmicos específicos, que permitan su óptimo estado de operación. En apego a lo anteriormente citado, es que se considera conveniente concientizar a la población en temas tan importantes para el bienestar social, como la selección de materiales y -consecuente- conservación de los recubrimientos de muros, no sólo para disminuir los costos de ejecución y mantenimiento, sino para aprovechar sus propiedades, ya que tienen una incidencia directa en lo relacionado con el control de las condiciones ambientales básicas, la regulación de la calidad del aire interior y por ende, en la salud de los usuarios. Dicha labor puede iniciar en la etapa formativa de los profesionales de la construcción, con la intención de normalizar el estudio o correcta selección de los sistemas constructivos en función del clima, pero también identificando la función de cada espacio; para garantizar así, que las propuestas de diseño responderán -satisfactoriamente- a los requerimientos de regulación de la humedad, mediante su absorción, transpiración y/o evaporación.

The level of indoor air quality (IAQ) has a direct incidence on the human health, therefore, is the object of study of bioclimatic design, since it promotes the harnessing environmental factors for the creation and conditioning of spaces in which users experience comfort and well-being. In addition, to encourage construction with common sense, where the rational use of resources and low energy dependence prevail. In this thesis it has been identified the properties of the materials that make up the most common wall coverings (hydrated lime, cement, cement mortar and gypsum) for recognizing those that best adapt to the weather in Mexico City, as it could be verified, they contribute to the control of some risk factors (physical:moisture, chemical:toxics and biological:microbes) related with a low indoor air quality at dwellings. This function mitigates or reduces the appearance of some of the most frequent respiratory ailments in users such as: allergies, asthma, rhinitis, flu and sinusitis. The analyses to which the coatings of four binding materials were subjected, allowed to evaluate their performance in the face of semi-controlled environmental factors (temperature, relative humidity, and carbon dioxide concentration) inherent to the operation of the interior space itself and the place of its location. Obviously, all the coatings reacted differently and according with the physical and chemical properties of the materials in each of them. Being the most representative and satisfactory variations, those related to the permeability and biocidal effect of coatings made with hydrated lime mixture. The pathologies that some coatings showed throughout the monitoring period, due to insufficient moisture management, the high microbial development, and the chemical nature of the binding material, were cryptoefflorescences, mold, bacteria and particle shedding/dissemination; they were defining to establish that in similar way to living beings, building materials need specific hygrothermal ranges, to let them works in an optimal state. According with the above, it is considered convenient to raise awareness among the population on issues as important for social welfare, such as the selection of materials and -consequently- conservation of wall coverings, not only to reduce the costs of execution and maintenance, but to take advantage of their properties, since they have a direct incidence in all related with the control of basic environmental conditions, the regulation of indoor air quality and therefore, in users’ health. This work can begin in the formative stage of construction professionals, with the intention of standardizing the study or correct selection of construction systems depending on the weather, but also identifying the function of each space; to guarantee that the design proposals will respond -satisfactorily- to the requirements of humidity regulation, through its absorption, transpiration and/or evaporation.

Muro, recubrimientos, patologías, salud. Wall, coating, pathologies, health. Indoor air pollution--Health aspects. Architecture--Health aspects. Interior walls. Protective coatings. Lime as a disinfectant. Building materials. Communicable diseases--Transmission--Prevention. Contaminación del aire interior. Muros interiores. Revestimientos. Cal como desinfectante. RA577.5 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS ARQUITECTURA DISEÑO ARQUITECTÓNICO

Microbiological Analysis of the Air in a Popular Fish Processing and Marketing Area

Angélica Sinaí Quintanilla Martínez Lizet Aguirre Güitrón Luis Daniel Espinosa Chaurand MAYRA DIAZ RAMIREZ ALEJANDRO DE JESUS CORTES SANCHEZ (2022, [Artículo])

"Fish are marketed as a food and consumed worldwide. During the production of food, contamination by microorganisms is possible through the air, soil, water, surfaces, food handlers, etc. The air does not have a natural microbial composition, but it is a vehicle for the transmission of microorganisms of economic and health interest because they are associated with food spoilage and human diseases. The objective of this study was the microbiological analysis of the air in an area popular for the processing and marketing of fish products in the city of Tepic Nayarit. Using the passive or sedimentation method to collect microorganisms present in the air, the proportion of aerobic mesophile bacteria, coliform bacteria, fungi and yeast was determined at different locations in the fish processing and marketing area for four weeks. The results indicated that the aerobic mesophiles had the highest counts among all the microbial groups analyzed at the twelve different sampling points during the four weeks of the study; their numbers ranged from 2.44 to 2.95 log CFU/m3/h, followed by molds with counts from 1.44 to 2.75 log CFU/m3/h, yeasts with counts from 0.7 to 2.01 log CFU/m3/h and coliforms with counts that ranged from 0.7 to 1.68 log CFU/m3/h. We determined the proportion of the viable microbiological population present in the air at the different sampling points of the study area; several of these sampling points presented values above those recommended by various agencies around the world. Knowledge of the biological hazards transported through the air is important to establish and reduce the risk to the health of occupants and the contamination pathways of processed and marketed fishery products that may be associated with spoilage and foodborne diseases."

food safety, food quality, air pollution, airborne biohazard, environmental monitoring INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LOS ALIMENTOS HIGIENE DE LOS ALIMENTOS HIGIENE DE LOS ALIMENTOS

Spatial Effects of Urban Transport on Air Pollution in Metropolitan Municipalities of Mexico

GERZAIN AVILES POLANCO Marco Antonio Almendárez Hernández Luis Felipe Beltrán Morales Alfredo Ortega Rubio (2022, [Artículo])

"The objective of this work was to estimate the local effects and spatial spillover effects of the number of vehicles, use of urban public transport, and population density on nitrogen oxide emissions for 405 metropolitan municipalities in Mexico in 2016. To this end, a Spatial Durbin Model was estimated. We found positive direct effects of the number of vehicles and population density and negative direct effects of the use of urban public transport. The number of vehicles in circulation had negative spillover effects on the nitrogen oxide emissions of neighboring municipalities. These results indicate that the design of public policy programs aimed at reducing air pollution in Mexico should be based on coordination across metropolitan municipalities."

private car transportation, air pollution, nitrogen oxide emissions, spatial spillover effects, metropolitan municipalities CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO METEOROLOGÍA CONTAMINACIÓN ATMOSFÉRICA CONTAMINACIÓN ATMOSFÉRICA