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Levels of BTEX (Benzene, Toluene, Ethylbenzene and p-Xylene) were determined in the ambient air of two urban sites located in the Metropolitan Area of Monterrey (MAM) during two climatic seasons of 2023. The study revealed that BTEX compounds in Santa Catarina and Obispado had the following relative abundance: p-Xylene (20.09 µg m−3) > Toluene (19.50 µg m−3) > Ethylbenzene (19.34 µg m−3) > Benzene (17.39 µg m−3). Their concentrations were consistent with global reports, showing diurnal and seasonal variability. Levels were higher during the dry season due to elevated temperatures, low wind speeds, and lack of precipitation, which reduced pollutant dispersion. BTEX concentrations in Santa Catarina (industrial site) and Obispado (urban site) were influenced by local activities like industrial processes, area sources, and vehicular traffic. Wind rose analysis confirmed the influence of local sources, with higher BTEX levels when winds came from the east. This was linked to pollutant transport within MAM and thermal inversions trapping pollutants during the dry season. Benzene/Toluene (B/T) and p-Xylene/Ethylbenzene (X/E) ratios showed that the sampling sites were influenced by vehicular sources and local fresh emissions. Benzene inhalation has an unacceptable lifetime cancer risk, urging MAM authorities to implement stricter regulations to protect public health. While non-cancer risks were within acceptable limits, controlling Benzene and p-Xylene emissions remains critical to improving air quality. [ABSTRACT FROM AUTHOR]

The current environmental deterioration of ecosystems is unquestionable, even though for some time now work has been done to change the dominant social paradigm that places Nature as a tool at the service of human beings. Environmental psychology proposes that environmental problems are strongly related to human behavior, thus, its studies are oriented to measure behavioral variables. To propose a version of the Ecological Behavior Scale (EBS) for use in Mexican populations, the psychometric properties of the instrument were explored, obtaining as a result an EBS scale of 28 items and three factors, with an overall Cronbach's alpha of .79. [ABSTRACT FROM AUTHOR]

This study reports the trace metal concentrations in PM10 collected in two urban sites of Campeche, Mexico (the INAH site, located in the downtown, and the TNL site, located in the Tecnologico Nacional de Mexico campus Lerma). Trace metals (Cd, Co, Cu, Fe, Mn, and Zn) were determined by flame atomic absorption spectroscopy, with Fe and Mn being the most dominant species. Cd and Co showed high values of enrichment factors, indicating that they were highly enriched by anthropogenic sources. A health risk assessment was carried out according to the IRIS-EPA methodology considering both carcinogenic and non-carcinogenic effects and different age and gender population groups. The TNL site showed cancer risk coefficients that exceed the maximum limits established by the EPA and the WHO (1 × 10−6 and 1 × 10−5, respectively), being higher for Cd and Co. The non-carcinogenic risk exceeded the limits recommended by the EPA, being higher in the INAH site for cobalt (HQ = 28.92). There is a latent risk that the exposed population may develop cardiovascular and respiratory diseases due to inhalation of the metals measured in PM10. It is necessary to carry out more continuous monitoring campaigns of trace metals linked to PM10 in this area to enable a better understanding of the effects of these contaminants on the health of the exposed population. The results of the present work constitute the first efforts to evaluate the trace metals concentrations in PM10 in urban areas of the city of Campeche, Campeche and can be used to develop programs focused on improving air quality. [ABSTRACT FROM AUTHOR]

A field study was carried out in the Metropolitan Area of Monterrey (MAM), the second most populated city in Mexico, characterized by increasing urbanization, high traffic density, and intense industrial activity. These characteristics commonly present high concentrations of air pollutants leading to the degradation of air quality. PM2.5 was analyzed for heavy metals at two urban sites located within the MAM (Juarez and San Bernabe) in order to determine sources, health risk, morphology, and elemental content during the COVID-19 pandemic (autumn 2020 and spring 2021). Twenty-four-hour samples of PM2.5 were collected at each site during 30-day periods using high-volume equipment. Gravimetric concentrations and 11 metals were measured (Ca, Cd, Co, Cu, Fe, K, Mg, Mn, Ni, Cr, and Pb) by different analytical techniques (flame atomic absorption spectroscopy, graphite furnace atomic absorption spectroscopy, and inductively coupled plasma optical emission spectroscopy). Selected samples were analyzed by scanning electron microscopy-energy-disperse spectroscopy in order to characterize their morphology and elemental content. PM2.5 concentrations exceeded the Mexican standard and WHO guidelines in Juarez during spring 2021. Cu, Cd, and Co were highly enriched by anthropogenic sources, and Ni, K, Cr, and Pb had a moderate enrichment. Mg, Mn, and Ca were of crustal origin. Bivariate statistics and PCA confirmed that alkaline metals originated from crustal sources and that the main sources of trace metals included traffic emissions, resuspension from soil/road dust, steel industry, smelting, and non-exhaust emissions at both sites. Lifetime cancer risk coefficients did not exceed the permissible levels established by EPA and WHO, implying that local residents are not at risk of developing cancer. Non-carcinogenic risk coefficients revealed that there is a possible risk of suffering cardiovascular and respiratory diseases due to inhalation of cobalt at the study sites. [ABSTRACT FROM AUTHOR]

Copyright of Revista Nutrición Clínica y Dietética Hospitalaria is the property of Sociedad Espanola de Dietetica y Ciencias de la Alimentacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agrociencia is the property of Colegio de Postgraduados and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Atmospheric benzene and carbonyls were studied in San Nicolas de los Garza, Nuevo Leon, during 2011 and 2012. The relative abundance for measured VOCs was the following: formaldehyde (9.06 μg m.-3) > acetaldehyde (8.06 μg m.-3) > benzene (0.65 μg m.-3). All measured VOCs had a clear seasonal trend with higher values of concentration during summer. Benzene and formaldehyde had a marked diurnal trend with the highest levels during morning, whereas acetaldehyde did not show a clear diurnal pattern. Meteorological analysis showed that the dominant winds came from NNE and ENE, suggesting that sources located in these directions contribute to the VOC levels. Principal component analysis (PCA) analysis revealed that photochemical activity influenced benzene and carbonyl levels during summer and that benzene was associated with vehicular traffic emissions during autumn and winter, showing good correlation with CO. Meteorological data showed that measured VOCs were influenced by regional sources. A health risk assessment showed that local exposure to carbonyls and benzene exceeded 1 × 10-6 for integrated lifetime cancer risk. People living in San Nicolas de los Garza, thus, have a probable risk of suffering cancer in their lifetime. It is, therefore, necessary to improve environmental policies for controlling VOC levels in this area. [ABSTRACT FROM AUTHOR]

The use of native strains of microorganisms from soils is an excellent option for bioremediation. To our knowledge, until now there has been no other group working on the isolation of Actinobacteria from contaminated soils in Mexico. In this study, samples of soils close to areas with oil activity in the State of Veracruz, Mexico, were inoculated for the isolation of Actinobacteria. The strains isolated were characterized morphologically, and the concentrations of NaCl and pH were determined for optimal growth. Strain selection was performed by the detection of a phylogenetic marker for Actinobacteria located at the 23S rRNA gene, followed by species identification by sequencing the 16S rRNA gene. Several haloalkalitolerant Actinobacteria were isolated and identified as: Kocuria rosea, K. palustris, Microbacterium testaceum, Nocardia farcinica and Cellulomonas denverensis. Except for C. denverensis, the biomass of all strains increased in the presence of anthracene. The strains capacity to metabolize anthracene (at 48 h), determined by fluorescence emission, was in the range of 46-54%. During this time, dihydroxy aromatic compounds formed, characterized by attenuated total reflectance Fourier transform infrared spectroscopy bands of 1205 cm-1 and 1217 cm-1. Those Actinobacteria are potentially useful for the bioremediation of saline and alkaline environments contaminated with polycyclic aromatic hydrocarbon compounds. [ABSTRACT FROM AUTHOR]

Short-term effects of air pollution on the number of hospital admissions in eight municipalities of the Metropolitan Area of Monterrey, Mexico, were assessed from 2016 to 2019 using a time-series approach. Air quality data were obtained from the Atmospheric Monitoring System of Nuevo Leon State (SIMA) which belongs to SINAICA (National System of Air Quality Information), providing validated data for this study. Epidemiological data were provided by SINAIS (National System of Health Information), considering admission by all causes and specific causes, gender and different age groups. Guadalupe had the highest mean concentrations for SO2, CO and O3; whereas Santa Catarina showed the highest NO2 concentrations. Escobedo and Garcia registered the highest levels for PM10. Only PM10 and O3 exceeded the permissible maximum values established in Mexican official standards. A basal Poisson model was constructed to assess the association between daily morbidity and air pollutants, from this, a second scenario in which daily mean concentrations of air pollutant criteria increase by 10% was considered. Most of pollutants and municipalities studied showed a great number of associations between an increase of 10% in their current concentrations and morbidity, especially for the age group between 5 and 59 years during cold months, excepting ozone which showed a strongest correlation during summer. Results were comparable to those reported by other authors around the world, however, in spite of relative risk index (RRI) values being low, they are of public concern. This study demonstrated that considering the nature of their activities, economically active population and students, they could be more vulnerable to air pollution effects. Results found in this study can be used by decision makers to develop public policies focused on protecting this specific group of the population in metropolitan areas in Mexico. [ABSTRACT FROM AUTHOR]