BOSTON UNIVERSITY SCHOOL OF MEDICINE Thesis SOLID STATE CHARACTERIZATION OF CORROSION PRODUCTS: DETERMINING TIME SINCE DEPOSITION by MEGAN

iii ACKNOWLEDGEMENTS I am grateful to so many who have encouraged me, instructed me, inspired me, and distracted me throughout the course of this project. Thank you to all of the BUSM Biomedical Forensic Sciences Program students and faculty for the support the last two years. First, I must thank my thesis advisor Catherine Grgicak. Your efforts and energy spent training me, teaching me the basics of electrochemistry and corrosion, and overall commitment to this project exceeded my expectations. I cannot thank you enough for the constant encouragement to push myself harder and generate a body of work to be proud of. I could not have done it without you. Thank you, Amy Reynolds, for aiding me in understanding SEM and for reading and editing my work while in the last weeks of your pregnancy. I am indebted to Anlee Krupp and Joel Sparks for the training and instrumentation used during the course of my project. Thank you Katie Webster for the hard work that you put into the beginning stages of this project. I am so appreciative of my friends and family. In particular, thank you to my San Diego friends for always having couches to crash on and ears to listen-especially when I needed a dose of sunshine. Corissa and Anna: thank you for the laughter, ladies nights, coffee dates, and general camaraderie. Alissa: your adventures and grammatical help were priceless. love you all. Mom: you have always been my champion. Thank you for believing in me. ABSTRACT Forensic analysts commonly examine ballistics evidence in forensic laboratories where gunshot residue, bullets and firearms can be examined to aid in criminal investigations. Despite extensive means and protocols to examine discharge residues from firearms, there is no current method available to determine time since submersion of a firearm in a body of water. When a firearm has been disposed of in a body of water and becomes corroded, its appearance is altered. However, characterizing the solid state of firearms and their corrosion products may provide information regarding time since deposition in aqueous environments. Previous studies which examined mass loss of four handgun slides and a stainless steel standard were conducted, and showed that without previous knowledge regarding metal composition, little can be said about the length of time a metal object has been exposed to a particular environment. Since a priori knowledge of gun composition is required, a detailed study …