Health hazards generally cause illnesses.
Safety hazards cause injuries.
The way an agent enters your body also can make a difference in what happens to you. There are four main ways that harmful agents can enter your body. You can swallow chemicals along with your food if you do not wash your hands after handling chemicals. In dusty areas you can swallow chemicals such as lead or asbestos particles that are in the air or that land on food or in drinks. Some diseases, such as hepatitis A, are spread by swallowing food or liquid that is contaminated with the hepatitis A virus.