In my research group we study the adverse effects of chemicals on biological systems with a focus on mitochondria. The types of chemicals we investigate include environmental contaminants, pesticides, plastics, nanoparticles and dietary fats. Mitochondria are important subcellular organelles that are called the powerhouse of the cell because they convert the food we eat to cellular energy known as ATP. One area of interest is the ability of chemicals to cause oxidative stress in mitochondria which involves the generation of reactive oxygen species (ROS) such as superoxide anion radical, hydrogen peroxide and hydroxyl radical. ROS can oxidize cellular protein, DNA and membranes causing dysfunction that eventually leads to cell death and disease. Organisms are able to defend themselves against the adverse effects of ROS by using antioxidant vitamins, enzymes and glutathione. Our work examines how chemicals and antioxidants interact to affect cellular and mitochondrial function. The scientific discipline for this type of research is toxicology which is represented nationally by the Society of Toxicology, SOT.