The Monterrey Metropolitan Area (MMA) is the third largest city in México. Few studies have been carried out regarding its air pollution. The aim of this study was to analyze the temporal behavior of PM 10 (particulate matter Յ10 m in aerodynamic diameter). Data reported by the "Sistema Integral de Monitoreo Ambiental" (Integrated Environmental Monitoring System) network from 2006 to 2008 were used. PM 10 levels were compared among the stations by year, season, and day of week. A bootstrap technique was used to obtain subsamples to which Student's t test and ANOVA were applied. PM 10 levels were high and exceeded the annual limit of 50 g/m 3 set up by the Mexican standard Norma Oficial Mexicana NOM-025-SSA1-1993. These levels could have serious health effects. The southwest zone of MMA had the highest levels of PM 10 during the period studied. Winter was the most polluted season, and summer was the least polluted season. Thursday and Friday were the most polluted days, and Sunday was the least polluted day. The hours with the highest levels of PM 10 were 8:00 to 10:00 a.m., whereas nighttime hours were the cleanest.
The air PM 2.5 concentration and its heavy metal content (Fe, Pb, Mn, Ni, As) were measured in the Metropolitan Area of Monterrey, Méxicoin Mexico, an area that is characterized by both very active and diverse industrial activity and intense highway traffic and industrial activity. The 24-h PM 2.5 samples were collected in two different zones during a 1-year-long measurement program (February 2008-February 2009). The year PM 2.5 average was above 15 µg/m 3 exceeding Mexican and international standards. The difference of PM 2.5 in each zone was not statistically significant. The greatest metal content was for iron, followed by lead, manganese, nickel and arsenic. The difference in metal content for Pb, Mn, and As was statistically significant.
Objetivo. Confirmar la presencia de dexametasona y diclofenaco como adulterantes de un producto comercializado como de origen natural. Material y métodos. Para la identificación y confirmación de la presencia de los fármacos se utilizó un método de análisis instrumental por cromatografía de líquidos de alta presión acoplado a espectrometría de masas en tándem. Resultados. En el análisis de 11 frascos de Reumofan Plus obtenidos de pacientes y médicos de la localidad se confirmó la presencia de dexametasona y diclofenaco. La metodología utilizada permitió separar los esteroisómeros dexametasona y betametasona, las abundancias relativas de iones productos 237.2 y 279.2 m/z permiten diferenciar espectralmente un compuesto de otro. Conclusiones. Se confirmó la presencia de dexametasona y diclofenaco en muestras de un producto comercializado como “100% natural” obtenidas de diferentes pacientes o médicos en el periodo enero a diciembre de 2011.
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