MedicalResearch.com Interview with: [caption id="attachment_60068" align="alignleft" width="150"] Dr. Goodrich[/caption] Jesse Goodrich PhD Assistant Professor Department of Population and Public Health Sciences Keck School of Medicine University of Southern California MedicalResearch.com: What is the background for this study? Response: Per- and poly-fluoroalkyl substances (PFAS) are a group of persistent chemicals that are known to interfere with hormones and metabolism. In our previous research, we have found that PFAS exposure is associated several specific diseases, especially in children and adolescents. These include obesity, type 2 diabetes, liver disease, and even liver cancer. However, we are still only just starting to fully understand all of the health effects of the many different PFAS in existence. Previous studies have focused primarily on one or two main PFAS. However, there are over 9,000 known PFAS, and people are exposed not just to a single PFAS but to mixtures of many PFAS. Importantly, the combination of these chemical exposures may affect us differently than single exposures alone. To address this challenge, we used an innovative approach to study design to examine how exposure to PFAS impacts biological processes which may underly the development of many different diseases in adolescents and young adults. To do this, we first measured thousands of naturally occurring chemicals, known as metabolites, in people's blood. Then, using a new biostatistical method developed by our team, we identified how exposure to a mixture of several PFAS impacted each individual chemical. Finally, we used this information to determine which biological processes are changed by PFAS exposure.