Abstract
Since Cyprus entered the European Union (EU) in 2004, there has been a rapid expansion associated with the development of major motorway networks, tourist centres, commercial and industrial activity within major cities. To date, very little research has been undertaken in Cyprus, to assess the impact of such urban development on chemical levels in the environment. This research aimed to assess the possible levels of chemicals in the southern part of Cyprus using the olive tree as a potential biomonitor for evaluating the degree of Mn, Cu, Zn, Pb, Cr, Co, Ni, V, Mo, Cd and As contamination in Cyprus. Olive tree bark, leaves, tree-rings, olives (olive oil) and surface soils were collected from four areas (rural, tourist, urban and transport). In addition, samples were collected from different urban centres namely: Nicosia, Larnaca, Limassol and Paphos. This study confirmed that olive tree bark could be used to assess the release of chemicals from anthropogenic sources, especially from urban and transport activities. Unwashed olive bark lead levels for highways (mean 25.2; range 0.63 to 119 mg/kg Pb dry weight) were significantly higher than for rural areas (1.62; 0.08 to 3.81 mg/kg Pb d.w.). The other parts of the olive tree have provided data on the mobility and accumulation of the elements and possible links between the different media (tree-rings, leaves, olives, olive oil and surrounding surface soils). The overall elemental levels for the southern part of Cyprus were found to be lower than reported literature values. This research has also found that the highest elemental levels are in samples from urban (Nicosia) and from transport sites. This is due to construction-demolition activities, road expansion (including re-surfacing and widening) and high vehicular traffic densities. Unwashed tree ring cores in Larnaca showed high levels of copper (41.3 to 54.9 mg/kg Cu d.w.) in segments which represented 20-30 years ago, showing the effect of the closure and decommissioning of the petroleum refinery. The elemental levels found in the tourist and rural areas were significantly lower. Rural or ‘non-polluted’ sites were used to provide control data for Cyprus. In addition, high elemental levels were not found in the olives and olive oil. Relatively high zinc levels (1.83 and 3.05 mg/kg Zn) were found in olive oils bought from the Cyprus and UK markets. There is no set limit for zinc which makes the evaluation of the risk difficult. Comparing the levels with the literature, the data was in agreement with levels found in other countries. Arsenic (total and speciation) analysis of the water and surrounding media (soils and poultry manure), near Nicosia, showed the highest arsenic levels to be 59.8 μg/l As in water, with the predominant species to be arsenate (Asv). A few groundwater As levels surpassed the World Health Organisation Guideline for drinking water (10 pg/lAs). In conclusion, continuous monitoring is necessary, as the island is rapidly growing and developing, especially major motorways and tourist/city centres. The database created through this research will be able to assist and provide a leading start to future studies for other researchers in Cyprus and other countries, especially in the Mediterranean who grow olives and are undergoing urban development.