Total emission, traffic

Ammonium in aerosols originates from the neutralisation of sulphuric and nitric acid by ammonia. Ammonia is emitted by different sources, most notably animal manure, traffic and application of fertiliser. In general, emissions are for the largest part (80-95%) associated with agricultural activities [19]. Erisman et al. [20] estimated the natural emissions at about 10% of the total emissions in Europe. This percentage includes contributions from wild animals and wetlands. We assume a similar percentage for ammonium in north-western Europe. 

An order of magnitude of the relative importance of traffic in the total emissions of carbon monoxide, hydrocarbons, nitrogen oxides, sulfur oxides and dust is shown in Fig. 2. From these data, it is apparent that road traffic is one of the major sources of carbon monoxide, hydrocarbons and nitrogen oxides emissions [1]. 

Figure 2. Total emissions of hydrocarbons (HC), carbon monoxide, nitrogen oxides (NO,v), sulfiir dioxide and dust in the Federal Republic of Germany in 1989, and relative importance of traffic.

Real-world emission rates of in-use motor vehicles (road traffic) can be quantified by measurements in road mnnels. The results reported for particle mass emissions in PMio varied from several mg veh km to some hundred mg veh km , with reduced amounts for the fine particle fraction PM2.5. The particles released mainly consist of EC, OC, soluble ions (NHj, S04 , NOs ) and mineral components (Si, Fe, Ca, Al, Mg). Trace metal emissions (Ba, Co, Cr, Cu, Mn, Ni, Pb, Sb, Sn, Sr, Ti, V, Zn) contribute usually for less than 1 % of total emissions in all size fractions. Observed particulate vehicle emissions could be attributed to several tailpipe and non-tailpipe sources. The main part of carbon emissions may be contributed to tail-pipe exhaust fraction, whereas the non-carbon emissions are most likely non-exhaust derived components. PMjo emissions are usually dominated by resuspended matter as well as by brake wear, whereas fine particles (PM2.5) are mainly derived from combustion processes. 

Maximum concentration of carbon monoxide has been exceeded in one area (Lower Silesia), due to the excess concentration in the health-resort Cieplice-Zdroj (near the Jelenia Gora). It should be noted that the concentrations of the standards for health resorts are much more stringent than for other areas. As can be seen from the data shown in Figure 1 the share of road transport in total emissions of this compound is high and the value is at the level 23.15%. Due to the location of the health resort area in the neighbourhood of major road transport routes with heavy traffic the sphere of road transport can cause excess of the limit. 

From the point of view of criterion (human health) for PM air pollution in only four areas the acceptable level of concentration has not been exceeded (cities of Elblag, Koszalin, Olsztyn and Zielona Gora). In other cities, and in all voivodships permissible concentration has been exceeded. As can be seen from the data shown in Figure 2 share of road transport in total emissions of particulate matter PM q fraction is at the level 10.36%. It can be concluded that one of the reasons for exceeding the limit value can thus be heavy traffic, especially in cities and towns over 100 thousand inhabitants. This reason is not dominant because the engines of new cars must comply with ever higher emission standards Euro. 

In densely populated areas, traffic is responsible for massive exhausts of nitrous oxides, soot, polyaromatic hydrocarbons, and carbon monoxide. Traffic emissions also markedly contribute to the formation of ozone in the lower parts of the atmosphere. In large cities, fine particle exposure causes excess mortality which varies between one and five percent in the general population. Contamination of the ground water reservoirs with organic solvents has caused concern in many countries due to the persistent nature of the pollution. A total exposure assessment that takes into consideration all exposures via all routes is a relatively new concept, the significance of which is rapidly increasing. 

The potential benefits of such measures can be illustrated by reference to a trial road charging scheme introduced in Stockholm city centre in 2006. It was estimated that the scheme resulted in a 15% reduction in total road use within the charging zone. Emissions of NOx and PM10 from road traffic in the zone fell by 8.5% and 13%, respectively [41]. 

The complexity of the urban environment does not always allow for a clear separation of road traffic sources consequently, most of source apportionment studies present results only for total contributions from road traffic. It is also common to find studies where the road dust component of traffic emissions is mixed with other mineral/soil sources. Nevertheless, for air quality management and exposure studies it is important to understand the individual source contributions. PM contributions from vehicular traffic should be differentiated between exhaust and non-exhaust. Ideally non-exhaust contributions should be further separated between road dust, brake, tyre and road wear. 

Still, considerable uncertainties exist with regard to the different kinds of nonexhaust PM emissions. In recent studies tyre abrasion, initially estimated to make up to 10% of total traffic PM10 contribution, has been shown with a new method for analysing specific rubber components to have much lower impact [62]. Accordingly, most tyre particles have aerodynamic diameters above 10 pm and their contribution to PM10 is 0.5 mass% at maximum. 

Other human activities that release arsenic include herbicide use, automobile traffic, marine vessels, glass manufacturing, steel production, waste incineration, Portland cement manufacturing, and the combustion of CCA-preserved wood ((Shih, 2005), 88 (Matschullat, 2000), 302 (Chein et al., 2006 Wasson et al., 2005 Frey and Zhao, 2004) Chapter 7). Total anthropogenic emissions of arsenic to the atmosphere are about 18 800-25 800 t per year (Shih, 2005), 88. 

Spring type the normalized concentration of PAHs increased with molecular size. 6-ring benzo[g,/z,z ]perylene, indeno[l,2,3-c<7]pyrene, and 5-ring benzo[b + k fluoranthene accounted for the majority of the total PAH concentrations, indicating that traffic emission was clearly a significant source of PAHs in spring. 

Ward, N.I., Dudding, L.M. Platinum emissions and levels in motorway dust samples influence of traffic characteristics. Sci. Total Environ. 334-335, 457 63 (2004)... 

LCI is the methodology for estimating the consumption of resources, the quantities of wastes, the emissions, the traffic accidents, the noise, etc., that are associated with each stage in a product s life cycle. The material and energy flows are modeled between the processes within a life cycle. The overall models provide mass and energy balances for the product system, its total inputs and outputs into the environment, on a per functional unit basis. 

The Dutch PRTR is a bit different from other PRTRs and comprises the inventory, analysis, localization, and presentation of emission data of both industrial and nonindustrial sources in the Netherlands. The PRTR is used as the national instrument to monitor the emissions from all sources to air, water, soil, and offsite transfers as waste. In total, some 800 substances are included in the Dutch PRTR. Data cover industry, public utilities, traffic, households, agriculture, and natural sources, and it is to some extent open to public. The emission data are partly updated every year and some 170 most important substances are covered in a report that is published annually in close cooperation with all actors in the field. 

In this work atmospheric concentrations of a large number of non-methane volatile organic compounds (NMVOCs) emitted by different anthropogenic sources, in particular from traffic exhaust and solvent use, have been investigated. The results from the studies should provide more information about the relative importance of road traffic and solvent use to the total NMVOC emission in Europe. 

Dijfuse sources are highly dynamic, spread out pollution sources and their magnitude is closely related to meteorological factors such as precipitation. Major diffuse sources under this definition include surface runoff (load from atmospheric deposition), groundwater, erosion (load from eroded material), diffuse loads of paved urban areas (atmospheric deposition, traffic, corrosion) including combined sewer overflows, since these events occur discontinuously over time and are closely related to precipitation (it has to be pointed out that emissions from urban areas are also partly involved in the point source term, so these discharges are not constant in reahty). Both point and diffuse sources contribute to the total contaminant load of rivers. 

Fig. 3 Values of the diagnostic ratio Cbaa C baa + cchr) fe refers to total atmospheric concentration, Cj g + Ci p) at 16 sites with well defined sources (Czech Republic) during various seasons in 2001-2008 influenced by road traffic and residential heating emissions...

For assessment of the contribution of traffic derived emissions to total pollution levels in an urban atmosphere, detailed information about the emission characteristics of motor vehicles operated under real-world conditions is needed. 

Composition and size distribution of the emitted particles depend on the contribution of the individual emission sources related with road traffic—in particular combustion and non-tail-pipe emissions. Tailpipe emissions are vehicle exhaust emissions which are produced during fuel combustion (including additives) and released through the vehicle tailpipe (Rogge et al. 1993 Cadle et al. 1999). The particles derived from tail-pipe emissions are mainly composed of EC and OC, thus average total carbon emission rates are usually very close to the PM mass emission rates. Inorganic anions account for some percent of total tail-pipe emissions, the contribution of the elemental fraction is also in the order of few percent. 

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