Atmosphere metals, emission

Table 3. Global heavy metals emissions into atmosphere and oceans (1(P tons per year).

Annual emissions of heavy metals from the anthropogenic sources of HELCOM countries significantly decreased during the period of 1990-2001. In particular, annual emissions of cadmium decreased by 45%, whereas lead and mercury emissions reduced by 60%. Following this reduction and also due to the changes of heavy metals emissions in other European countries the level of atmospheric depositions to the Baltic Sea has also significantly decreased (Figure 20). Compared to 1990... 

The results reported by Carrasco et al. (1998) revealed that nearly all studied metal emissions, measured at the exit of a cement kiln stack, were significantly higher when a blend of 80 wt% coal + 20 wt% TDF was combusted instead of pure coal. Especially notable are increased emissions in Cr, Mn, Cu, Zn, and Pb (Table 9). The exception to this trend is Hg, which exhibited a 30% reduction in its emission rate when the coal + TDF mixture was burned. The data further document reductions in NO and organic compound emissions, including PAHs, where the most drastic decrease was observed for dioxins and furans. On the other hand, emissions of CO, S02, and HC1 increased considerably with the addition of TDF (Table 9). The total particulate emissions from combustion of the blend were only slightly greater than those from pure coal. Carrasco et al. (1998) used their data to model atmospheric dispersion of the emitted contaminants in the vicinity of the... 

Vinylidene chloride can enter the atmosphere as emissions from its production and use in the manufacture of plastics. It has been detected in wastewater from plastics manufacturing and metal finishing (United States National Library of Medicine, 1997). 

Bhanarkar, A.D., Rao, P.S., Gajghate, D.G. and Nema, P. (2005) Inventory of SO2, PM and toxic metals emissions from industrial sources in Greater Mumbai, India. Atmospheric Environment, 39(21), 3851-64. 

Pacyna, J.M., Munch, J. and Axenfeld, F. (1991) European inventory of trace metal emissions to the atmosphere. In Heavy Metals in the Environment (ed. Vernet, J.R). Elsevier, Amsterdam. 

The continuous vaporization of cosmic dust in the upper atmosphere leads to permanent metal atom layers at altitudes between 90-100 km. As pointed out in the introduction, the metals play an important role in the lower regions of the ionospheric region (see Fig. 2). The first manifestation of upper atmospheric metals was noticed early this century, when coarse spectra of the night sky revealed a line at 589.2 nm. In 1929, Slipher suggested that this emission line was due to sodium.Later studies refined the measurement to 589.3 nm, and tne identification of the Na-D emission line was definitely made. Shortly after, the first association of the Na-D line emissions in the nightglow with meteors entering the Earth s atmosphere was made by a number of authors.The actual chemical mechanism that can lead to optical emission of the Na-D line was first suggested by Chapman" ... 

From the above data it is obvious that atmospheric emissions on land are a major source of heavy-metal contamination to our natural environment. In the following sections the focus will be on these emissions due to the fact that there are numerous data available to constmct emission estimates (Nriagu and Pacyna, 1988) and that historical atmospheric emissions have been archived in continental ice accumulations (Greenland and Antarctica). The metal emission estimates of Nriagu and Pacyna (1988) are the most complete, and recent data are available for worldwide metal emissions. 

The presence of heavy metals in the atmospheric particulate matter in Antarctica can be attributed to different sources, both natural and anthropogenic. Some authors state that almost all natural sources of heavy metals in Antarctica are generally situated in the southern hemisphere (4, 14, 15). The natural sources are normally volcanic activities, erosive processes, continental dusts, marine spray from the ocean, low-temperature biological processes, etc. (7, 10, 16-18). Important local human sources of heavy metal emissions into the Antarctic atmosphere are presumed to be the Antarctic stations and their activities, especially all kinds of transport, power plants, waste burning (incinerators), etc. (10, 12, 15, 19). 

A project was undertaken to perform retrospective reconstruction of environmental histories at the sites of previous long term atmospheric metal exposures. The effort required development of appropriate emission information and dispersion modeling capabilities on both the regional and urban spatial scales. The development of useful urban scale emission inventories dating back several decades proved to be a limiting factor. At present, therefore, the retrospective reconstruction of environmental histories is not possible for the large number of sites in the metals corrosion data base. This precludes derivation of damage functions at this time. 

According to the 1992 inventory of heavy metal emissions in the Slovak Republic, stationary sources played a significant role in lead emissions. Steel and iron production (Kosice, Podbrezova) emitted the largest amounts of lead to the atmosphere (43%). The power sector (coal combustion) and non-ferrous metal production were also significant contributors (17 and 7%, respectively). Traffic was the second largest source of lead emissions in 1992, after iron and steel production, representing about... 

As with all atmospheric species, trace metal emissions undergo atmospheric transport and dilution before they reach a particular receptor site. Mathematical models can be constructed based on the fundamentals of atmospheric chemistry and physics that will track the contributions from many emission sources as they undergo atmospheric transport. Indeed, the development of such models will receive considerable attention in this book. In the case of particulate emissions, an alternative is available. It is possible to attack the source contribution identification problem in reverse order, proceeding from measured particulate concentrations at a receptor site backward to the responsible emission sources (see Chapter 24). The unique metals content of the emissions from each source type is viewed as a fingerprint for the presence of material from that source in an ambient aerosol sample. 

Table 1 The main sources of metal emissions to the atmosphere in 1995 (tonnes/year) (data from Pacyna and Pacyna 2001)...

Fig. 4 Global metal emissions to the atmosphere by region (tonnes/year) for arsenic (As), cadmium (Cd), mercury (Hg) and molybdenum (Mo) (a) chromium (Cr), copper (Cu) and manganese Mn (b) nickel (Ni), lead (Pb), vanadium (V) and zinc (Zn) (c) and antimony (Sb), selenium (Se), tin (Sn) and thallium (Tl) (d) (data from Pacyna and Pacyna 2001)...

Caggiano R, Ragosta M, D Emilio M, Macchiato M (2001) Rye grass species as biomonitors of atmospheric heavy metal emissions. Fresenius Environ Bull 10 31-36... 

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