Ideas in this flowchart

• Environmental substances and energy sources can increase free radicals in the body.
• They can add to or accelerate the production of free radicals.
• Relevant exposures include excessive sunlight, ozone, smoke, heavy metals, ionizing radiation, asbestos, and other toxic chemicals.
• Some environmental substances increase free radicals because they are free radicals themselves.
• Other substances add energy that provokes electrons to move between atoms.
• Excessive environmental exposure can contribute to disease.
• The exposure can overwhelm the body's free radical detoxifying systems.
• It can also overwhelm processes that repair oxidative damage.