Dustin, Malia; Holden, Maliea; Peterson, Rob; Chilom, Gabriela (Dixie State University)
Faculty Advisor: Chilon, Gabriela (Dixie State University, Chemistry)
Particulate matter (PM) is a complex mixture of extremely small particles and liquid droplets suspended in air. Particles vary in terms of origin, chemical composition and size. Particles with diameter of 10 µm and smaller carry an increased risk for human health as they can penetrate deeper into the lungs, even to the alveolar regions. Recent studies suggest that trees can remove particles from the atmosphere through their leaves and their removal capacity depends on the chemistry and morphology of the leaves.
The goal of this project is to analyze the composition of PM for three species of trees commonly grown in St George, Utah: Pyrus Calleryana Bradford, Prunus x Cistena, and Chilopsis Linearis. The amount of PM accumulated on the surface of leaves was determined gravimetrically for two size fractions (2.5-10µm and 10-100µm). Both fractions were analyzed by inductively coupled plasma-mass spectrometry (ICP MS) after acid digestion of filters that collected PM. The average concentrations of the following metals: Mn, Fe, Co, Ni, Cu, Zn, Ti, V, Cr, As, Zr, Mo, Se, Cd, Sn, Sb, Pt, and Pb is reported.
The accumulation of heavy metals on leaf surfaces can prevent the metals from being airborne, therefore reducing the exposure of residents to PM pollution.