Detection of Polycyclic Aromatic Hydrocarbons in Magnolia Leaves
Authors:Sylvine Deprele, Yeneri Torres
Mentor:Sylvine Deprele, Professor of Chemistry, Mount St. Mary's College
Polycyclic Aromatic Hydrocarbons (PAHs) are potent pollutants composed of fused aromatic rings and are of a major concern to our environment and health. PAHs are deteriorating non polluted environments and a few are linked to being carcinogenic, mutagenic, and teratogenic. The purpose of our research is to analyze the concentrations of pollution in the Los Angeles area through the collection of leaves from three locations. Magnolia trees are commonly found in the Brentwood neighborhood as residential and street trees. These trees are evergreen and carry large size leaves with high surface area, which are necessary components for pollutant collection. Three distinct areas were chosen for examination: a private mountainside (MSMC campus), a busy main street (Sunset Blvd.), and an interstate freeway (I-405). The leaves were analyzed for PAH (pollutants) qualification and quantification from each location. We predicted the leaves with the most PAHs would be from the Church Ln. location because it's close to all the pollution from Interstate 405. The collected leaves went through an extraction process by homogenization, sonication, filtration, and evaporation. Once we obtained the concentrated samples; we used Gas Chromatography Mass Spectrometry (GC/MS) to detect the PAHs and separate the components of the sample. We used standards of common PAHs as controls. Unfortunately, we were unable to identify pure PAHs in our solutions but managed to categorized derivatives of Naphthalene from the Chalon and Church Ln. samples. We anticipate revising our extraction methodology and the solvents used in order to improve our results.