Dusts - Emissions and Pollutions 1991

Map Description

Emissions – Total Dust 1989

All groups of emitters are grouped together in the Map 03.04.1. They present a picture which is far from uniform. Particularly high emissions can be discerned in the vicinity of power and heating stations and in the vicinity of the cement works in Rüdersdorf to the east of Berlin. Further maximums can be associated with the various industrial zones distributed through the city, without any one such zone standing out.

Since Unification there have been changes in Berlin, as in the new German states, which have had significant impact on the emissions of airborne pollutants. The decline in the use of coal and of unprocessed brown coal in particular, has had a significant influence on the level of air pollution. As the emissions surveys are only continued in stages of several years, it was not possible to adapt the data to the period in which the pollution measurements were made. It has been assumed that the total dust emissions in East Berlin and surrounding region in 1991 were lower than in 1989, the year to which the data in Map 03.04.1 relates.

Pollutions – Floating Dust 1991

In contrast to previous years the Maps 03.04.2 and 03.04.3 now show only very minor variations in concentrations between the individual stations for the average yearly value and the 98 %-value of pollution. The values measured on the outskirts were comparatively low. The average yearly values here are between 58 and 66 µg/m3, and the 98 %-values between 172 and 184 µg/m3, i.e. 60 % of the pollution values of TA-Luft.

The maximum average yearly value of 94 µg/m3 (63 % of the IW1 of TA-Luft) was recorded at the station in Oberschöneweide and the maximum 98 %-value of 302 µg/m3 at the station in Friedrichshain. Thus the concentration of floating dust in Friedrichshain lies just above the pollution value IW2 (300 µg/m3) of TA-Luft, which in the 1985 Environmental Atlas also applied to parts of Wedding, Reinickendorf, Tiergarten and Kreuzberg (cf. Map 03.04.2, SenStadtUm 1985).

Increased values are shown by stations within this range which are in the vicinity of roads such as the road monitoring station in Charlottenburg, where the average yearly value of 83 µg/m3 is 16 µg/m3 (20 %) above the level of the surrounding stations and the 98 %-value of 211 µg/m3 is higher by 17 µg/m3 (10 %).

The lowest average yearly value of 49 µg/m3 was recorded at the station in Grunewald. Monitoring here is conducted beneath the treetops at a height of 4.5 m. Measurements at this height show greatly reduced wind speeds which hinder the transportation of pollutants. Filter effects in the treetops play an additional role. A 20 % lower concentration of floating dust was recorded in contrast to neighboring monitoring stations where the air can circulate freely. As no measurements are made of the major vertical air movements, it is not possible to quantify the absorption effect of the trees. Treetop-zone assessments have been drawn up for individual constituents of floating dust (calcium, lead and cadmium) in the framework of the research and development plan “forest ecosystems in the vicinity of conurbations”. This allows the role of individual factors such as treetop permeability and trunk run-off to be determined (cf. Fischer 1993). This research revealed the great significance of the treetop zone for the interception of pollutants. The quantity of acids deposited in the treetop zone was partially twice that registered for open spaces.

Constituents – Floating Dust 1991

A selection of six of the total of 17 recorded substances is shown in the Maps 03.04.4., 03.04.5 and 03.04.6. Map 03.04.4 shows the average yearly concentrations of arsenic, cobalt, chromium and nickel, which are classified as carcinogenic.

Concentrations of arsenic ranged from a minimum of 5.9 nanograms per cubic meter (ng/m3, 1 ng = 0.001 µg) at the monitoring point in Grunewald to maximum values of 7.7 ng/m3 in Tegel and Lichtenberg. The mean variation of the measured values of eight percent from the city’s total average value reveals only minimal local variations. Most of the time only very low values for this substance are recorded in the entire urban area. These values are in the region of the detectability threshold of the given measuring process (1 ng/m3). The relatively high average values are due to concentrations increasing sharply on a limited number of days. On these days the wind blows from an east-south-easterly to a south-south-westerly direction and all stations record almost equally heightened concentrations (in 1991 up to 70 ng/m3). It can therefore be assumed that broad plumes of smoke or dust containing arsenic particles are transported by the wind to Berlin and beyond. Emitters in Berlin itself would appear to play next to no role. In view of the wind direction the pollution is considered to stem from the winning and processing of non-ferrous metals north of Wroclaw (Poland) and in the German state of Thuringia.

Similar to arsenic, there are only minimal distributive variations in nickel concentrations in the urban area – 13 % mean variation from the monitoring stations’ average values. Correspondingly no substantial emissions of this substance either are to be expected in Berlin.

The concentrations of cobalt and chromium at the monitoring point in Grunewald are only half as high as those in the central parts of the city. At the monitoring point in Tegel, in the vicinity of an industrial zone with iron- and steel-processing works, and at the autobahn monitoring point in Charlottenburg the values are up to 40 % above those in the city center. Only small differences can be recorded at the other monitoring points. On the basis of the measurements obtained it can be assumed that particular industries and also motor-vehicle traffic contribute significantly to the pollution of Berlin’s air with these substances.

Maps 03.04.5 and 03.04.6 show particularly large variations in the concentrations of lead and cadmium with a range of around 35 %. The concentration of these substances at the monitoring point in Grunewald was low – 73 ng/m3 of lead and 0.99 ng/m3 of cadmium were recorded. However, the accumulation of these substances in the humus on the forest floor must also be taken into consideration, so that even low pollution rates can lead to problems over longer periods of time (cf. Gensior et al. 1992). The highest lead concentration of 303 ng/m3 was measured at the autobahn monitoring point in Charlottenburg and the highest cadmium concentration of 3 ng/m3 at the monitoring point in Tegel close to the industrial zone.

The lead concentration in the air is still caused largely by motor vehicles using leaded petrol, although the pollution level in the last several years has declined significantly. In addition to traffic, lead and cadmium are also emitted by a number of small industrial polluters. However, the concentrations reach less than 20 % of the pollution values of TA-Luft and the limit level of the EC-guideline or Regulation no. 22 of BImSchV. Also in the 1985 Environmental Atlas the lead and cadmium pollution in close proximity to roads was significantly higher than the concentrations recorded at monitoring points far from roads. In residential areas in general it reached 10 % of the pollution values of TA-Luft, in close proximity to roads 25 %.

Dust Precipitation Including Constituents

Due to the special set-up of the dust precipitation collectors the pollution measurements must be considered in two separate groups.

The first group consists of collectors which, following the requirements of TA-Luft, are set up more than 20 m away from direct sources of pollution. At monitoring points of this group minimum yearly average dust precipitation values of 50 to 60 mg/m2 per day are measured where the immediate vicinity has unbroken plantings of trees and grass or is surrounded by water. This precipitation is largely determined by the constituents of the rain and pollen. Average yearly values for dust precipitation in residential areas in Berlin are between 70 and 210 mg/m2 per day. Values under 140 mg/m2 per day are recorded if there is relatively abundant greenery in the vicinity of the monitoring point. If the surroundings consist of streets, pavements or unsealed ground the values are between 140 and 210 mg/m2 per day. Where there is little green and also heavy traffic the precipitation can rise to between 210 and 280 mg/m2 per day.

Map 03.04.7 (dust precipitation) suggests that the values recorded in East Berlin tend to be higher than those in West Berlin. But when the monitoring points are in comparable surroundings it can be shown that the high values of between 200 and 280 mg/m2 per day measured in the eastern boroughs Pankow, Prenzlauer Berg, Mitte are also to be found in western boroughs such as Tegel, Steglitz and Neukölln.

The standard monitoring points with readings of over 300 mg/m2 per day should be treated as exceptions. These stations are either in industrial areas with a very heavy flow of traffic, such as Marienfelde and Tegel, or were subject to extreme conditions in their surroundings in the period in which measurements were carried out (a major building-site in Kaulsdorf, a holiday parking-lot in Berlin’s south east).

The second group consists of the collectors set up immediately beside or on the median strip of main roads with heavy traffic. These monitoring points serve to determine the level of dust precipitation and lead pollution from motor-vehicle traffic. It is here at the edge of the city autobahn with a daily traffic volume of 150,000 vehicles that the highest dust precipitation of up to 756 mg/m2 per day is registered. The third-highest value is recorded in Grunewald on the edge of the main road AVUS, where motor-vehicle traffic and rain are the only factors of significance. A similar picture to that of dust precipitation is given in Maps 03.04.8 and 03.04.9 which show the yearly averages of lead and cadmium in dust precipitation. In areas with heavy flow of traffic a comparison with the corresponding maps of the 1985 Environmental Atlas confirms the frequency of increased dust precipitation and the higher proportion of lead and cadmium in this precipitation.

Two monitoring points are of particular note. In comparison with the very low level of pollution from dust precipitation at the Grunewald Tower (73 mg/m2 per day), the monitoring point here reveals relatively high levels of lead and cadmium pollution (47 µg/m2 and 0.7 µg/m2 per day respectively) which are above those of the surrounding area. It is highly probable that these values are due to the corrosion protection (treatment with cadmium and minium) of lightning rods and fittings on the roof of the tower. This monitoring point is thus unsuitable for determining dust constituents.

The road monitoring point in the borough Friedrichshain shows a significantly higher level of lead pollution in comparison with dust precipitation pollution and compared with other monitoring points. In 1991 this may have been a late consequence of the higher level of lead in petrol in the former GDR.