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