Symptoms that show up quickly are called acute effects . For example, exposure to chlorine makes it hard to breathe, and causes nausea, and stinging and burning sensations in the eyes, nose and throat. Many health problems are long lasting but do not show up right after an exposure. The symptoms or disease happen long after exposure or from being exposed to small amounts of an agent for a long time. These delayed or long lasting problems are called chronic effects.
Cancer is an example of a disease that develops years after exposure.
A health effect is local when it only affects the part of the body exposed. A broken toe, a cut finger and a burn are examples of local effects. A health effect is systemic when an agent enters the body and causes damage to other parts of the body. A cut that gets infected and causes fever and other symptoms is systemic. Breathing a chemical that makes you feel high or dizzy may cause liver or kidney damage if you are exposed over a long time, even if you have never had any acute or local effects.