La contaminación del aire y las variables meteorológicas asociadas al número de casos y defunciones por SARS-CoV-2 en la Zona Metropolitana de Guadalajara / Air pollution and meteorological variables associated with the number of cases and deaths from SARS-CoV-2 in the Guadalajara Metropolitan Zone

Objetivo: Aunque se sabe que el COVID-19 se transmite de persona a persona, no está claro si los contaminantes atmosféricos y parámetros meteorológicos promueven su transmisión. Métodos: Se realizó un estudio ecológico transversal para correlacionar contaminantes atmosféricos, variables meteorológicas, casos y defunciones por COVID-19 en la Zona Metropolitana de Guadalajara. Resultados: El análisis multivariado mostró que las correlaciones con casos y defunciones en orden descendente fueron: Bióxido de azufre (SO2), Monóxido de carbono (CO), Bióxido de nitrógeno (NO2), Partículas 2.5μm (PM2.5), Temperatura (T), Velocidad de viento (VV), Humedad Relativa (HR), Ozono (O3) y Partículas 10μm (PM10). El modelo lineal general evidenció mayor variabilidad al SO2, seguido de PM10, HR, PM2.5, T, NO2, VV, O3 y CO para los casos; en las defunciones, el orden fue SO2, PM2.5, PM10, HR, T, O3, CO, NO2 y VV. Conclusión: Los contaminantes atmosféricos y factores meteorológicos influyen en los casos y defunciones por COVID-19.

Study of the Behavior of Air Parcels, using PIXE, Hysplit and Wind Rose in the Metropolitan Zone of Toluca Valley, Mexico

Aim: The objective of this work was to determine the behavior of the trajectories of the air plots in two sites (San Mateo Atenco-(SM) and San Lorenzo Tepaltitlán-(SL)), in the atmosphere of the Metropolitan Zone of the Toluca Valley (MZTV). Methodology: In the atmosphere of the MZTV, using HYSPLIT a Backward trajectory direction analysis was performed from June 29 to July 8, 2021, considering for each day the summertime schedules of the center, indicating its Coordinated Universal Time (UTC). An ANOVA analysis (with a significance level of α=0.05) was performed for the concentrations of SM and SL obtained with PIXE, with the objective of seeing the equality of their behavior. Results: The behavior of the direction of the trajectories of the air plots in both sites is similar and the trajectories for the same day are the same in both sites but different on another day; It was determined that during night-day (19 to 12 h of the following day) the behavior is similar and changes during the remaining time, being variable. In general, the origin of the trajectories of the air plots for both sites of the MZTV is predominantly from the southeast, a situation that was confirmed with Wind Roses. Of the ANOVA analysis, the p-value was in all cases greater than the significance level of 0.05, the null hypothesis was accept, and it is possible to conclude that the elemental chemical composition of PM2.5 have equal means in both sites. Conclusion: Among other, it is possible to consider the behavior of meteorological parameters and thus take them into account for sampling studies of criteria pollutants such as PM2.5.

Changes in the temperature of the Guadalajara metropolitan zone, México under climate change scenarios / Cambios en la temperatura de la zona metropolitana de Guadalajara, México bajo escenarios de cambio climático

In the present study analyzed the average and extreme temperatures observed and simulated by regional models in the Guadalajara Metropolitan Zone (GMZ), Jalisco, Mexico. Data of daily mean, minimum and maximum temperatures of stations in the GMZ during the period 1971-2000 have been used to study the observed changes in the average and extreme temperatures. In addition, an assessment of future scenarios for the average and extreme temperatures associated with the increase in the concentration of greenhouse gases was performed using simulations of a PRECIS regional climate modeling to create the climate for present (1971-2000), and future projections for 2030, 2050 and 2080. Observational analysis of stations suggests warming through increased intensity and frequency of hot events and also with the decrease in the frequency of cold events. More than 35 to 76% of the stations have a tendency to the decrease in the number of cold events and near 39 to 64% of the stations show a growing trend in the hot events. The percentage of stations to global warming through the rates of intensity of the highs maximums, lowest minimum temperatures is 37 to 70% and the 30 to 65% of the stations, respectively. Observational analysis for the GMZ as a whole also shows similar results. Anomalies to the average and extreme temperatures per month during the period of data show an increase (decrease) in the frequency of hot (cold) events for every month. In general, PRECIS simulations under both scenarios A1B and A2 indicate warm events increase and decrease of the cold extreme events towards the end of the 21st century. Both show similar patterns, but the scenario A2 shows slightly lower magnitudes of projected changes. Temperatures are likely to increase in the year, but it is expected that changes in summer to be more prominent.

An Overview of Bioaerosols Suspended in the Atmosphere of Metropolitan Zone of Toluca Valley

Particulate matter (PM) is recognized as a type of pollutant emitted through the air that generates adverse health effects. Bioaerosols are PM of biological origin, that has not been morphologically characterized as exhaustively as other types of PM. The term bioaerosols collectively refers to all dead or living airborne particles with biological origins, including pollen, fungi, bacteria, viruses, plant or animal debris, as well as fragments and products of pathogenic microorganisms. Pathogenic airborne microorganisms may have public health consequences. Bioaerosols suspended in ambient air from the Metropolitan Zone of Toluca Valley (MZTV), State of Mexico were identified by scanning electron microscopy followed by energy dispersive x-ray spectroscopy, to determine their morphology, elemental chemical composition, and average sizes. The bioaerosols detected were pollen, spores, microorganisms, fragments, and diatoms that exhibited diverse morphological structures; while some particles had rough or smooth surfaces, others were spongy and spherical or had irregular or thorny surfaces. Others, yet, had well-structured surfaces such as the amoeba that were detected in the study. EDS analyses carried out on SEM samples demonstrated that C and O were the main chemical elements of them. The main components of diatoms were the silicon and oxygen. The particle radii (r) of detected pollen was 2 µm ≤ r ≤ 23 µm, spores were 0.17 µm ≤ r ≤ 3.7 µm, microorganisms were 0.16 µm ≤ r ≤ 12 µm, and diatoms were 2.3 µm ≤ r ≤ 23 µm. Bioaerosols aerodynamic sizes range can be potentially poses adverse health effects. Resumen. El material particulado (MP) se reconoce como un tipo de contaminante emitido a través del aire que genera efectos adversos para la salud. Los bioaerosoles son MP de origen biológico, que no han sido caracterizados morfológicamente tan exhaustivamente como otros tipos de MP. El término bioaerosoles se refiere colectivamente a todas las partículas muertas o vivas transportadas por el aire con orígenes biológicos, que incluyen polen, hongos, bacterias, virus, restos de plantas o animales, así como fragmentos y productos de microorganismos patógenos. Los microorganismos patógenos transportados por el aire pueden tener consecuencias para la salud pública. Los bioaerosoles suspendidos en el aire de la Zona Metropolitana del Valle de Toluca (MZTV), Estado de México, fueron identificados mediante microscopía electrónica de barrido seguido de espectroscopía de rayos X de energía dispersiva, para determinar su morfología, composición química elemental y tamaño promedio. Los bioaerosoles detectados fueron polen, esporas, microorganismos, fragmentos y diatomeas que exhibieron diversas estructuras morfológicas; mientras que algunas partículas tenían superficies rugosas o lisas, otras eran esponjosas y esféricas o tenían superficies irregulares o espinosas. Otros, sin embargo, tenían superficies bien estructuradas como la ameba que se detectó en el estudio. Los análisis de MEB-EDS realizados en muestras demostraron que el C y el O eran los principales elementos químicos de las mismas. Los principales componentes de las diatomeas fueron el silicio y el oxígeno. El radio de partícula (r) del polen fue de 2 µm ≤ r ≤ 23 µm, las esporas fueron de 0.17 µm ≤ r ≤ 3.7 µm, los microorganismos fueron de 0.16 µm ≤ r ≤ 12 µm y las diatomeas fueron de 2.3 µm ≤ r ≤ 23 µm. El intervalo de tamaños aerodinámicos de los bioaerosoles puede presentar efectos adversos para la salud.

Cytogenotoxicity Evaluation of Young Adults Exposed to High Levels of Air Pollution in a Mexican Metropolitan Zone Using Buccal Micronucleus Cytome Assay

Air pollution has become a serious public health problem globally. Recent studies support the harmful effect of air pollution on human health, in addition to scientific evidence that recognizes it as a human carcinogen. The buccal micronucleus cytome (BMC) assay is employed extensively to measure cytotoxic and genotoxic damage in a population exposed to environmental contamination. The objective of this study was to evaluate the cytotoxic and genotoxic effects in healthy young adults exposed to different levels of air pollution and to identify areas with air pollution rates above the regulatory limits. This study was performed through the BMC assay in oral mucosa samples from 80 healthy young adults from the Guadalajara metropolitan zone. Three highly contaminated areas were taken into account: Tlaquepaque, Miravalle, and Las Pintas. Las Aguilas, a less contaminated area, was used as a reference. The frequencies of nuclear abnormalities in the areas with the highest and lowest levels of air pollution were compared with the Mann–Whitney U test. In addition, an analysis of the concentration of environmental pollutants, particulate matter ≤ 10 μ m (PM10), ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO), were carried out in the mentioned areas, in order to identify the events above the regulatory limits in a year period. The results showed that young adults exposed to a higher concentration of pollutants showed higher frequencies of nuclear abnormalities. The individuals from the areas of Tlaquepaque, Miravalle, and Las Pintas showed cytotoxic damage since statistically significant differences were found in the abnormalities of pyknotic nuclei (PNs), condensed chromatin (CC), karyorrhexis (KX), and karyolysis (KL). The individuals who showed the most cytotoxic damage were from the Las Pintas area with higher frequencies in nuclear abnormalities (PNs, CC, KX, and KL) ( p < 0.0001 ). Genotoxic damage was found in individuals from two zones, Miravalle and Las Pintas, with statistically significant differences in the abnormality of nuclear buds (NBUDs) ( p < 0.0001 ). Our results suggest that exposure to high levels of air pollution in healthy young adults has an effect on cellular and nuclear integrity and thus in human health, since areas with higher air pollution showed an increase in cytotoxicity, specifically in early and late markers of cell death (CC, KX, PN, and KL) and genotoxic damage (BUDs).

“AMONG DEAD AND WOUNDED”: MAPPING, CHARACTERIZATION AND ANALYSIS OF FIRES WITH VICTIMS IN RECIFE’S METROPOLITAN ZONE

This article presents the mapping and analysis of fires with dead and wounded people in the Metropolitan Region of Recife (MRR) served by the Firefighters Department from 2013 to 2016. There was an average rate of 1 death per million inhabitants, similar to countries such as Singapore and Vietnam. The weighted number of fires per wounded or dead person results in rates of 0.5 and 1.7 per 100 recorded fires, respectively. These numbers are concerning, especially when compared to rates from other regions in the world. The victims of fires in MRR were shown to generally not be a perceivable problem in terms of common sense, yet they are real and require accurate analysis and effective measures.

The Seismic Network of Zapopan: Evaluating the local seismicity of the western Guadalajara Metropolitan Zone

&lt;p&gt;The Municipality of Zapopan, Jalisco, is located west of the Guadalajara Metropolitan Zone at the intersection of three rift zones: Tepic-Zacoalco, Chapala-Tula, and Colima. The importance of this region lies in the recent population growth that it has experienced in a few years. This growth has been supported by the development in commercial and service activities, and mainly in industry and technology, being ranked as the second-most populous city in Mexico, behind the federal capital.&lt;/p&gt;&lt;p&gt;The western region of the Guadalajara Metropolitan Zone (GMZ) has numerous fault systems where, historically, there have been significant earthquakes and seismic swarms such as those that occurred in 1685-1687, 1875, 1932, 1995 and 2002, showing similar characteristics. Besides, it is in this region where the Caldera de la Primavera is located, a rhyolitic volcanic caldera that continues presenting seismic and geothermal activity.&lt;/p&gt;&lt;p&gt;Recently, in the years 2015 and 2016, new seismic swarms occurred and were recorded instrumentally for the first time by the Jalisco Seismic and Accelerometric Network (RESAJ). The two seismic sequences took place in two alignments in the same direction as the Colima rift. These epicenters suggest the existence of two almost parallel normal faults, and that would be forming the Graben of Zapopan. Due to the length of these faults, 16 km for the east fault, and 28 km for the west fault, earthquakes of magnitudes 6.2 - 6.5 could be generated.&lt;/p&gt;&lt;p&gt;In the framework of the CeMIEGeo P-24 project (SENER-CONACyT), we continue studying the seismicity of this region with the deployment of 25 seismic stations in the vicinity of La Caldera de la Primavera. This study revealed the high seismicity that was taking place in the area of &amp;#8203;&amp;#8203;Zapopan, Tesist&amp;#225;n Valley, and La Caldera de la Primavera.&lt;/p&gt;&lt;p&gt;Based on these new studies and the knowledge of the seismic history of the region, a collaboration agreement has been established between the Research Group UDG-CA-276 SisVOc and Civil Protection of the Municipality of Zapopan for the installation of a local seismic network that will allow to define tectonic and structurally the fault systems of the region and mitigate the possible effects of the local seismicity in the population. Since May 2019, three Obsidian 8X seismic stations with Lennartz 1Hz LE3D and Episensor sensors and two accelerometers installed in the city have been operating, constituting the Zapopan Seismic and Accelerometric Network (RESAZ). The RESAZ operates together with the nearest stations of the RESAJ. In this work, we present the first results of the seismicity analysis recorded in Zapopan.&lt;/p&gt;