Atmospheric particulates particle/vapor distribution

Once in the air, pesticides can exist as vapor, liquid aerosols or be sorbed/partitioned on dust and particulates. Even though in-depth information exists for particle phase distributions of organics in the atmosphere (24, 25, 26, 27, 28), few studies have appeared in the literature that assesses the vapor/aerosol distribution of pesticides under actual tropospheric conditions (29). Further research to determine how pesticides are distributed among atmospheric phases will be needed to better gauge the overall significance of wet/d deposition versus gas and particle-phase transformation processes occurring in air. 

If released to the atmosphere, most of the 23 plasticizers in Table 18.1 can, in the vapor phase, be soibed by air-borne particulate matter which is subject to rain out and gravitational settling. Weschler concluded for example, that adsorption of phthalates by dust particles was responsible for the wide-spread distribution of the chemicals in an office... 

Atmospheric pollutants can occur in a variety of forms, namely, fumes, dust, gases and vapors, and mists and aerosols. The knowledge of the distribution of atmospheric pollutants between the gaseous and the particulate phase is very important for the environmental analytical chemist. Gases and particles, in fact, are very different in terms of their adverse effects on human health and on the ecosystem they generally involve different formation pathways and removal processes. 

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