Diurnal and seasonal variation of volatile organic compounds in the atmosphere of Monterrey, Mexico

Atmospheric Levels of Benzene and C1-C2 Carbonyls in San Nicolas de los Garza, Nuevo Leon, Mexico: Source Implications and Health Risk

“…The formaldehyde and acetaldehyde concentrations in the present study were lower than those reported in downtown Monterrey, Nuevo Leon, Mexico by Menchaca-Torre et al [42] and similar to those reported in Chendu (China) [49], but higher than those reported in Longmen Southern China during 2012-2013 by Guo et al [50].…”

“…Additionally, around noon, the increasing surface air temperature removes the thermal inversion and increases the mixed layer depth to its afternoon maximum. Menchaca-Torre et al [42] observed the same behavior in afternoon benzene concentrations measured during 2011 and 2012 in a nearby location in Monterrey, including accelerated secondary pollutant production from photochemical reactions, decreasing VOC levels especially between 2:00 and 6:00 p.m.…”

“…This is more than twice the value found in this study. In a second study [42] at this same site these authors reported formaldehyde and acetaldehyde values slightly higher than those reported in this study. The higher benzene concentrations reported at the Obispado site [42] are likely due to the Obispado site's location not only within an industrial zone, but also 42 km from a Mexican Petroleum Company (PEMEX) refinery (Cadereyta, Nuevo Leon).…”

“…In a second study [42] at this same site these authors reported formaldehyde and acetaldehyde values slightly higher than those reported in this study. The higher benzene concentrations reported at the Obispado site [42] are likely due to the Obispado site's location not only within an industrial zone, but also 42 km from a Mexican Petroleum Company (PEMEX) refinery (Cadereyta, Nuevo Leon). Despite reporting higher mean concentrations, the diurnal variation in benzene reported by Menchaca et al [42] was similar to that found in this study: VOCs exhibited a higher concentration in the 6:00-10:00 a.m. time interval, and decreased during the subsequent two sampling intervals.…”

“…Menchaca-Torre et al [42] reported a mean value for benzene of 1.5 µg/m 3 for Obispado, which is located in the center of Monterrey near San Nicolas de los Garza). This is more than twice the value found in this study.…”