Health Hazard (types of):
1. Acute toxicity: The older term used to describe immediate toxicity. Its former use was associated with toxic effects that were severe (e.g., mortality) in contrast to the term "subacute toxicity" that was associated with toxic effects that were less severe. The term "acute toxicity" is often confused with that of acute exposure. 2. Allergic reaction: Adverse reaction to a chemical resulting from previous sensitization to that chemical or to a structurally similar one. 3. Chronic toxicity: The older term used to describe delayed toxicity. However, the term "chronic toxicity" also refers to effects that persist over a long period of time whether or not they occur immediately or are delayed. The term "chronic toxicity" is often confused with that of chronic exposure. 4. Idiosyncratic reaction: A genetically determined abnormal reactivity to a chemical. 5. Immediate versus delayed toxicity: Immediate effects occur or develop rapidly after a single administration of a substance, while delayed effects are those that occur after the lapse of some time. These effects have also been referred to as acute and chronic, respectively. 6. Reversible versus irreversible toxicity: Reversible toxic effects are those that can be repaired, usually by a specific tissue's ability to regenerate or mend itself after chemical exposure, while irreversible toxic effects are those that cannot be repaired. 7. Local versus systemic toxicity: Local effects refer to those that occur at the site of first contact between the biological system and the toxicant; systemic effects are those that are elicited after absorption and distribution of the toxicant from its entry point to a distant site.
|
