Study of heavy and trace elements atmospheric deposition by means of the moss biomonitoring in Georgia

Author: Omari Chaligava
Keywords: heavy and trace elements, atmospheric deposition, biomonitoring, mosses, neutron activation analysis, Atomic absorption spectrometry
Annotation:

Nowadays air pollution is a serious worldwide problem caused by anthropogenic activities and is closely related to the environmental situation, economics, and human health. Heavy and trace elements concentrations in atmosphere are much lower than those that induce acute effects, so the principal air pollution concern about metals is the longer-term, low concentration exposures. Referring to the World Health Organization, mortality rate attributed to household and ambient air pollution in the biggest cities of Georgia is very alarming (WHO, 2016). It must be admitted that air pollution monitoring is continuously performed only in Tbilisi, Kutaisi, Chiatura and Batumi and the concentrations of pollutant allowed by law is often exceeded. Unfortunately, there is a lack of data in the rest of the country, as such monitoring is expensive. The advantage of the moss biomonitoring technique is that it is inexpensive and can be easily used for investigations of large territories, what increases the confidence and precision in estimation. The use of epiphytic plants as passive biomonitors is an established method of determining atmospheric deposition. In Scandinavia, mosses have been used as biomonitors for determining pollution with heavy metals since the late 1960s. Numerous projects have since been carried out with mosses; the method has been developed systematically and also used in large-scale European studies. Since 2001, the European biomonitoring program has been coordinated by the UNECE ICP-Vegetation under the Convention on Long-range Transboundary Air Pollution (LRTAP Convention). Later, in 2014, the moss survey coordination centre has moved to the Joint Institute for Nuclear Research and Head of this center is Assoc. Prof. Marina Frontasyeva. The possibilities of biomonitoring technique for geophysical conditions of Georgia were preliminary investigated by a small team with the head of Assoc. Prof. Shetekauri (TSU, Tbilisi) and support of Assoc. Prof. Marina Frontasyeva (JINR, Dubna) and her team, using neutron activation analysis in 2014 (Shetekauri S., 2015). The aims of the present study were to determine levels of trace elements in mosses from different regions of Georgia, to identify the areas where there is a high deposition of heavy and trace elements and to compare the results to the European data. To perform all these, mosses were analyzed using epithermal Neutron activation and atomic absorption spectrometry. The data was statistically analyzed and GIS technologies were used to visualize data. This research was performed in the frame of Shota Rustaveli National Science Foundation grant AR/198/9-240/14 (28.04.2015-28.04.2017) and Grant of Plenipotentiary of Georgia in JINR, Order #18 of 15.01.2016.