Sulfates, airborne particulates containing

Solids containing oxidized anions (carbonates, sulfates, hydroxides, and oxides) are the dominant forms of Cu in airborne particulate matter. In the few studies that have addressed the reactions of these particles in atmospheric washout, about 50% of the copper has been found to be soluble. Since the solubility is strongly dependent on pH, acid precipitation and acidification of receiving waters may have a significant effect on the form and fate of airborne copper. 

As discussed in Chapter 7, polluted air varies in composition from locale to locale and with the time of day and meteorological conditions in a given locale. Polluted urban air contains oxides of sulfur and nitrogen, carbon monoxide, ozone, uncombusted and partially combusted hydrocarbons from gasoline and diesel vehicles, and particulate matter. PM 2.5 particulates, the standard for evaluating pollution related to cardiovascular disease, are composed of combustion products, airborne soil, sulfates, nitrates, and heavy metals as listed in Table 29.4.141-45 ... 

The first joint shipboard and airborne smdy related to the chemical compositiOTi and water-uptake behavior of particulates in ship emissions was conducted on emissions from a Post-Panamax class container ship off the central coast of California. The results showed that the majority of particles outside the ship plume did not show slow water uptake kinetics as compared to ammonium sulfate, but in-plume particles with critical supersaturation between 0.1% and 0.35% had slower uptake kinetics than ammonium sulfate [288]. 

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