M. Tomašević

Active moss biomonitoring of trace elements with Sphagnum girgensohnii moss bags in relation to atmospheric bulk deposition in Belgrade, Serbia

Active biomonitoring with wet and dry moss bags was used to examine trace element atmospheric deposition in the urban area of Belgrade. The element accumulation capability of Sphagnum girgensohnii Russow was tested in relation to atmospheric bulk deposition. Moss bags were mounted for five 3-month periods (July 2005-October 2006) at three representative urban sites. For the same period monthly bulk atmospheric deposition samples were collected. The concentrations of Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, and Pb were determined by instrumental neutron activation analyses and atomic absorption spectrometry. Significant accumulation of most elements occurred in the exposed moss bags compared with the initial moss content. High correlations between the elements in moss and bulk deposits were found for V, Cu, As, and Ni. The enrichment factors of the elements for both types of monitor followed the same pattern at the corresponding sites.

Monitoring of trace element atmospheric deposition using dry and wet moss bags: accumulation capacity versus exposure time.

To clarify the peculiarities of trace element accumulation in moss bags technique (active biomonitoring), samples of the moss Sphagnum girgensohnii Rusow were exposed in bags with and without irrigation for 15 days up to 5 months consequently in the semi-urban area of Belgrade (Serbia) starting from July 2007. The accumulation capacity for 49 elements determined by ICP-MS in wet and dry moss bags was compared. The concentration of some elements, i.e. Al, V, Cr, Fe, Zn, As, Se, Sr, Pb, and Sm increased continuously with exposure time in both dry and wet moss bags, whereas concentration of Na, Cl, K, Mn, Rb, Cs, and Ta decreased. Irrigation of moss resulted in a higher accumulation capacity for most of the elements, especially for Cr, Zn, As, Se, Br, and Sr. Principal component analysis was performed on the datasets of element concentrations in wet and dry moss bags for source identification. Results of the factor analysis were similar but not identical in the two cases due to possible differences in element accumulation mechanisms.

First assessment of the PM10 and PM2.5 particulate level in the ambient air of Belgrade city.

Intention, Goal, Scope, BackgroundAs the strong negative health effect of exposure to the inhalable particulate matter PM10 in the urban environment has been confirmed, the study of the mass concentrations, physico-chemical characteristics, sources, as well as spatial and temporal variation of atmospheric aerosol particles becomes very important.ObjectiveThis work is a pilot study to assess the concentration level of ambient suspended particulate matter, with an aerodynamic diameter of less than 10 µm, in the Belgrade central urban area. Average daily concentrations of PM10 and PM2.5 have been measured at three representative points in the city between June 2002 and December 2002. The influence of meteorological parameters on PM10 and PM2.5 concentrations was analyzed, and possible pollution sources were identified.MethodsSuspended particles were collected on Pure Teflon filters by using a Mini-Vol low-volume air sampler (Airmetrics Co., Inc.; 5 1 min-1 flow rate). Particle mass was determined gravimetrically after 48 h of conditioning in a desiccator, in a Class 100 clean room at the temperature T = 20°C and at about 50% constant relative humidity (RH) .Results and DiscussionAnalysis of the PM10 data indicated a marked difference between season without heating - (summer; mean value 56 ug nr3) and heating season - (winter; mean value 96 µg m3); 62% of samples exceeded the level of 50 µg nr3. The impact of meteorological factors on PM concentrations was not immediately apparent, but there was a significant negative correlation with the wind speed.ConclusionsThe PM10 and PM2.5 mass concentrations in the Belgrade urban area had high average values (77 µg nr3 and 61 µg m3) in comparison with other European cities. The main sources of particulate matter were traffic emission, road dust resuspension, and individual heating emissions. When the air masses are coming from the SW direction, the contribution from the Obrenovac power plants is evident. During days of exceptionally severe pollution, in both summer and winter periods, high production of secondary aerosols occurred, as can be seen from an increase in PM2.5 in respect to PM10 mass concentration.Recommendation and OutlookThe results obtained gave us the first impression of the concentration level of particulate matter, with an aerodynamic diameter of less than 10 µm, in the Belgrade ambient air. Due to measured high PM mass concentrations, it is obvious that it would be very difficult to meet the EU standards (EEC 1999) by 2010. It is necessary to continue with PM10 and PM2.5 sampling; and after comprehensive analysis which includes the results of chemical and physical characterization of particles, we will be able to recommend effective control measures in order to improve air quality in Belgrade.

Trace element content in urban tree leaves and SEM-EDAX characterization of deposited particles

Leaves of common deciduous trees: Aesculus hippocastanum and Tilia spp. from three parks within the urban area of Belgrade (Serbia) were studied as biomonitors of trace elements (V, Cr, Fe, Ni, Cu, Zn, As, Cd, and Pb) air pollution. Using a scanning SEM-EDAX, the size, size distribution, morphology and chemical composition of individual particles were examined on adaxial and abaxial surfaces of the leaves. Morphological and chemical composition indicated that the most abundant particles were soot and dust with minor constituents such as Pb, Zn, Ni, V, Cd, Ti, As, and Cu. Total element concentrations in the leaves were determined by ICP-OES and ICP-MS. This investigation included spatial, seasonal, and temporal variations in leaves of the selected species. The leaves of A. hippocastanum showed a significantly higher elements concentration and more consistency in trend of element accumulation during the vegetation season in the period 2002-2006 than Tilia spp., so it may be considered as a more suitable species for the assessment of trace element atmospheric pollution, especially Pb and Cu which correlated with the bulk deposition data.

Residential heating contribution to level of air pollutants (PAHs, major, trace, and rare earth elements): a moss bag case study

In areas with moderate to continental climates, emissions from residential heating system lead to the winter air pollution peaks. The EU legislation requires only the monitoring of airborne concentrations of particulate matter, As, Cd, Hg, Ni, and B[a]P. Transition metals and rare earth elements (REEs) have also arisen questions about their detrimental health effects. In that sense, this study examined the level of extensive set of air pollutants: 16 polycyclic aromatic hydrocarbons (PAHs), and 41 major elements, trace elements, and REEs using Sphagnum girgensohnii moss bag technique. During the winter of 2013/2014, the moss bags were exposed across Belgrade (Serbia) to study the influence of residential heating system to the overall air quality. The study was set as an extension to our previous survey during the summer, i.e., non-heating season. Markedly higher concentrations of all PAHs, Sb, Cu, V, Ni, and Zn were observed in the exposed moss in comparison to the initial values. The patterns of the moss REE concentrations normalized to North American Shale Composite and Post-Archean Australian Shales were identical across the study area but enhanced by anthropogenic activities. The results clearly demonstrate the seasonal variations in the moss enrichment of the air pollutants. Moreover, the results point out a need for monitoring of air quality during the whole year, and also of various pollutants, not only those regulated by the EU Directive.

Moss bag biomonitoring of airborne toxic element decrease on a small scale: A street study in Belgrade, Serbia.

A database of potentially hazardous substances, necessary for estimating the exposure of humans to air pollutants, may be deficient because of a limited number of regulatory monitoring stations. This study was inspired by undeniably harmful effects of human long-term exposure to intense traffic emissions in urban area. Moss bag biomonitors were used to characterize spatial variation of airborne toxic elements near crossroads and two- and one-lane streets. The Sphagnum girgensohnii and Hypnum cupressiforme moss bags were exposed for 10 weeks to 48 sampling sites across Belgrade (Serbia) during the summer of 2014. In addition, oven-drying pretreatment of the moss bags was tested. During the experimental period, traffic flows were estimated at each site by counting the number of vehicles during the rush hours. The concentrations of 39 elements were determined in the moss samples. There was no significant difference between the results obtained for nontreated and oven-dried moss bags. For the majority of elements, the moss bags identified a common pattern of decrease in the concentration from crossroads to two- and one-lane streets. The exposed moss bags were enriched with Sb, Cu and Cr. The correlation coefficients (r=0.65-0.70) between the moss concentrations of Cr, Cu, Fe and Sb and the site-counted traffic flows also confirmed a dependence of the airborne element content on traffic emissions. A strong correlation with traffic flows makes Sb, Cu and Cr reliable traffic tracers.

Assessment of Air Quality in an Urban Area of Belgrade, Serbia

Mirjana Tasi a, Slavica Rajsi a, Milica Tomasevi a, Zoran Miji a, Mira Ani i a, Velibor Novakovi a, Dragan M. Markovi a, Dragan A. Markovi b, Lazar Lazi c, Mirjana Radenkovi d and Jasminka Joksi d aInstitute of Physics, Belgrade, Serbia bFaculty of Applied Ecology, Singidunum University, Belgrade, Serbia cInstitute of Meteorology, Faculty of Physics, Belgrade, Serbia dInstitute of Nuclear Science Vin a, Belgrade, Serbia

The novel approach to the biomonitor survey using one- and two-dimensional Kohonen networks.

To compare the applicability of the leaves of horse chestnut (Aesculus hippocastanum) and linden (Tilia spp.) as biomonitors of trace element concentrations, a coupled approach of one- and two-dimensional Kohonen networks was applied for the first time. The self-organizing networks (SONs) and the self-organizing maps (SOMs) were applied on the database obtained for the element accumulation (Cr, Fe, Ni, Cu, Zn, Pb, V, As, Cd) and the SOM for the Pb isotopes in the leaves for a multiyear period (2002–2006). A. hippocastanum seems to be a more appropriate biomonitor since it showed more consistent results in the analysis of trace elements and Pb isotopes. The SOM proved to be a suitable and sensitive tool for assessing differences in trace element concentrations and for the Pb isotopic composition in leaves of different species. In addition, the SON provided more clear data on seasonal and temporal accumulation of trace elements in the leaves and could be recommended complementary to the SOM analysis of trace elements in biomonitoring studies.

Trace Elements and Radionuclides in Urban Air Monitored by Moss and Tree Leaves

In urban areas, air quality is strongly influenced by numerous anthropogenic activities. High population density, heavy traffic and domestic heating in winters in the centre, and various industrial activities at the outskirts, influence atmospheric concentrations of trace elements and radionuclides. Consequently, large population is exposed to possible adverse effects arising from the altered urban air composition. Therefore, air quality monitoring has become one of the standard quality control procedures in urban areas.

The first survey of airborne trace elements at airport using moss bag technique

Air traffic represents an important way of social mobility in the world, and many ongoing discussions are related to the impacts that air transportation has on local air quality. In this study, moss Sphagnum girgensohnii was used for the first time in the assessment of trace element content at the international airport. The moss bags were exposed during the summer of 2013 at four sampling sites at the airport ‘Nikola Tesla’ (Belgrade, Serbia): runway (two), auxiliary runway and parking lot. According to the relative accumulation factor (RAF) and the limit of quantification of the moss bag technique (LOQT), the most abundant elements in the samples were Zn, Na, Cr, V, Cu and Fe. A comparison between the element concentrations at the airport and the corresponding values in different land use classes (urban central, suburban, industrial and green zones) across the city of Belgrade did not point out that the air traffic and associated activities significantly contribute to the trace element air pollution. This study emphasised an easy operational and robust (bio)monitoring, using moss bags as a suitable method for assessment of air quality within various microenvironments with restriction in positioning referent instrumental devices.