983694 - Trace Elements Enrichment Factor from Cupressus Macrocarpa Used as Biomonitor in a High Pollution Industrial Area of Puchuncaví Valley, Chile

In central Chile is located the Puchuncaví valley. In this area there is an important industrial complex which main activities are copper smelting and coal-fired power plants, among others. Due to the type of activity developed in the area, the environment is strongly affected by the anthropogenic pollution, such as discharged of atmospheric deposition, gaseous pollutants and deposition of metal-rich particles. Plants such as Cupressus macrocarpa, tend to accumulate pollutant elements in leaves due to their great ability to adapt to the chemical variabilities of the environment.

The goal of this study was to evaluate in Cupressus macrocarpa the enrichment factor of trace metals coming from the industrial complex (IC), such as: As, Ca, Cd, Cu, Mo, Pb, S, Sb and Zn.

Leaves of 1 year old were sampled during April 2016, in 5 sites: La Greda (LG), Los Maitenes (LM), Puchuncaví (Pu), Valle Alegre (VA) and a Control Site. These sites are located at different distance from the IC. For the trace element analysis, leaves unwashed were first frozen, then lyophilized, milled in an agate mill, digested with acid and subsequently analyzed by ICP-MS (7900, Agilent). The enrichment factor (EF) was calculated as a percentage for each element and monitoring point using the following equation (1):

〖EF〗_E=(〖CE〗_sample-〖CE〗_control)/〖CE〗_control x 100 (1)
Where EFE is the enrichment factor of the element E, CEsample is the concentration of element E in the leaf sample, and CEcontrol is the concentration of element E in the leaf sample from Control Site (CS). For the interpretation criteria, EF > 100% indicates significant enrichment, EF of 50-100% indicates moderate enrichment, while EF < 50% indicates normal conditions.

The EF of the elements as Cu, As, Mo, Pb and Sb were observed enriched significantly in all sites evaluated, LG, LM, Pu and VA. Besides in LG, the closest site to IC, as well was enriched significantly for the elements Cd, S and Zn. A critical case was observed for Cu in two site closet to IC, (LG and LM), where an EF> 3000 % was calculated, also the Cu value in leaves in this areas were found in phytotoxic levels.

Acknowledgements
ANID + FONDECYT + Folio (11200853), and Centre for Environmental Technologies (CETAM), Universidad Técnica Federico Santa María, Chile.