Arsenic and SO2 hotspot in South-Eastern Europe: An overview of the air quality after the implementation of the flash smelting technology for copper production.

This extensive study considered the air pollution data after the flash smelting technology for copper production had become fully operational. The assessment of the air quality after the implementation was significantly important, since the modernisation was necessary for reducing the environmental contamination in one of the most polluted regions in South-Eastern Europe. The concentrations of SO2, PM10 and toxic elements (As, Pb, Cd, Ni) in PM10 samples were monitored at different sites, with respect to the copper smelter, in the period 2016-2019. The air quality evaluation was performed concerning the corresponding limit and target values defined by the Serbian and European legislation, as well as the World Health Organization Air Quality Guidelines (WHO AQG). The measured SO2 concentrations indicated frequent exceedances of the defined daily and annual limit values, at both national and European level. Although exceedances were not as pronounced as in the period before the implementation of the new technology, the episodes of extreme air pollution with SO2 persisted on the daily basis. The maximum daily SO2 concentration of 2125 µg m-3 was more than 100 times higher compared to the WHO AQG, but lower compared to the period before the implementation of the flash smelting technology. The air quality considering PM10 and especially As levels in PM10 samples was notably poorer after the modernisation. The annual target value for As, defined by the European and Serbian Regulation, was exceeded at all the measuring sites, with maximum exceedance of more than 90 times at the suburban site during 2019. The frequent exceedances of the corresponding annual limit and target values were also denoted for Pb and Cd in PM10 samples. The analysed data emphasised that the Bor area could still be characterised as an environmental hotspot in Serbia and beyond.

Assessment of As, Cd, Cu, Fe, Pb, and Zn concentrations in soil and parts of Rosa spp. sampled in extremely polluted environment.

This research was conducted in order to determine As, Cd, Cu, Fe, Pb, and Zn concentrations in soil and parts of wild rose (Rosa spp., predominantly Rosa canina L.) in the Bor area, known for more than 100 years of mining and pyrometallurgical production of copper, as well as to determine the possibility of its usage as an environmental indicator or for phytoremediation. The results showed that the sampled soils were highly contaminated with As and Cu, since the obtained concentrations exceeded the corresponding limit and remediation values. The soil samples from the sites which were closest to the Mining-Metallurgical Complex or in the prevailing wind directions were most enriched with the analyzed elements. According to the element analysis in the parts of Rosa spp., branches, leaves, and roots contained higher concentrations of the studied elements than the fruits. Based on the values of the biological factors, it can be concluded that Rosa spp. restricted the absorption of the elements from the soil. Since the absorption rates from soil to roots were low for all the studied elements, Rosa spp. was not suitable for the phytoextraction or phytostabilization. Statistically significant positive correlations of the elements in the soil and parts of Rosa spp. indicated their anthropogenic origin. Differences in the element concentrations in the plant parts and the soil samples from the background and the sites which were under the influence of the emissions from the Mining-Metallurgical Complex indicated that Rosa spp. had a potential for usage in biomonitoring.

Metal/metalloid content in plant parts and soils of Corylus spp. influenced by mining-metallurgical production of copper.

The town of Bor and its surroundings (Serbia) have been under environmental pollution for more than a century, due to exploitation of large copper deposits. Naturally present Corylus spp. were sampled in the surroundings of the mine and flotation tailings at 12 sites distributed in six zones with different pollution loads, under the assumption that all the zones were endangered except for the background. As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb and Zn inputs from soil and the air were evaluated in plant parts, in terms of absorption, accumulation and indication abilities of Corylus spp. The obtained results showed that As and Cu were the most enriched elements in soil, and their concentration exceeded the limit and remediation values proposed by the regulation. Plant parts (root, branch, leaf and catkin) also showed enrichment of most studied elements in wide ranges. According to the enrichment factor for plant, metal/metalloid inputs, particularly in leaves, were from anthropogenic origin. Plant absorption which occurred at the soil-root interface was low, based on the bioaccumulation factor, which could be indicative of resistance mechanisms of root to abiotic stress induced by a high content of elements in soil substrate. The values of bioaccumulation coefficient suggested weak and intermediate absorption and exclusion abilities of Corylus spp. to the studied elements. Element concentrations differ in unwashed and washed leaves, as well as pollution loads in plant and soil samples from the background, traffic and the sites with clear mining-metallurgical influence. Therefore, Corylus spp. could be promising in biomonitoring studies.

Extreme air pollution with contaminants originating from the mining-metallurgical processes.

Levels of SO2 and metals/metalloids in the air near a copper smelter in Bor (Serbia) from 2009 to 2015 were presented in this study. Annual levels of SO2 were constantly above the proposed limit value (LV), at almost all the measuring sites. SO2 concentrations on an annual level measured in different zones in Bor were several times higher compared to the LV in 2011, 2012, 2014 and 2015. Enormously high daily SO2 concentrations measured at the suburban zone (3734µgm-3) was 187 times higher than the LV given by the World Health Organization. Annual arsenic concentrations exceeded the LV at all the measuring sites during the study period. Extremely high annual As level in 2012 was 21 times higher than the LV proposed by the European Union. The annual lead and cadmium concentrations frequently exceeded the LV. The vicinity of the measuring sites to the copper smelter and the location of the sites in regard to the prevailing wind directions contribute to higher content of air pollutants. The data presented in this study revealed that extremely high concentrations of air polluting substances could rank the town of Bor as one of the most polluted regions in Serbia and beyond.