Measurements of formaldehyde and acetaldehyde in the atmosphere of Mexico City

Ambient levels of carbonyls were measured at the University of Mexico campus, Mexico City. Only formaldehyde and acetaldehyde were measured, since aldehydes with higher molecular weight were not detected. The most abundant aldehyde was formaldehyde, with an overall ratio CH3CHO/H2CO of 0.43. Maximum concentrations occurred for formaldehyde at 10:00 h while for acetaldehyde at 8:00 h. Comparing the concentration measured in this work with those in urban areas it was found that the formaldehyde and acetaldehyde levels in Mexico City are among the highest reported in the literature.