Sampling and identification of pollen, associated with the determination of metals as an index of environmental pollution.

MOYANO MF, .; DAGUERRE A, ; ISAGUIRRE AC, ; MOGLIA MM

Mendoza

Congreso; Congreso SBC 2018; 2018

Sociedad de Biología de Cuyo (SBC)

People are exposed to a great diversity of environmental pollutants, coming from anthropogenic activities. Metal pollution has been increasing rapidly over the past century, and at the same time, the human population has continued to rise and producing contaminants. Thus, particles such as pollen grains may contain various trace elements, and their amounts vary from one species to another. They can present traces of metals such as lead (Pb), barium (Ba), cobalt (Co) and manganese (Mn), which are among the most common soil contaminants and are considered toxic to living beings. In the present work we propose a simple and fast method for the multielemental determination of traces in aerobiological samples. The sample of aeroparticles was obtained with a volumetric Lanzoni sensor, which is located on the terrace of the National University of San Luis. This device allows the capture of particles suspended in the air with a week periodicity, and with a suction flow of 10 l of air min-1, similar to the volume of air inhaled by the human lung. The pollen content was analyzed for three months of continuous aerobiological sampling, in the atmosphere of the city of San Luis, Argentina. Pollen samples were readed with an optical microscope at 400 X and they were identified through palynological atlases and with the pollen library belonging to Aerobiology´s laboratory. For multielement determination, a mass spectrometer with inductively coupled plasma (ICP-MS) was used. The aeroparticle samples were subjected to acid digestion at 90 ° C for one hour. The conditions of analytical determination in the sample were optimized. The nebulizer gas flow used was 0.87 l min1 and the RF power was 1100 W. The pollination period extended from August to October. Comparatively with others pollen types, Moraceae, Cupresaceae and Ulmus were the most abundant in the atmosphere of San Luis. Linear regression models were used to analyze the metals vs pollen content. Positive associations were found between Mn (y=0.12x + 8.53; r= 0.12, P=0.0012) and Ba (y=0.03x + 4.85; r= 0.03, P=0.73) with Cupresaceae. In the same sense it was observed positive associations between Pb (y=0.12x + 1.59; r= 0.12, P