What is meaning of Toxicity?

The degree to which a substance (a toxin or poison) can harm humans. Exposure to toxic or poisonous substances causes harm to human health and in more extreme cases can lead to serious injury or death. Toxicity is an intrinsic property of a chemical and cannot be modified. Even the slightest exposure to a highly toxic substance can result in serious health problems. However, correct medical first aid treatment following exposure can mitigate the consequences.

Generally there are three defined types of toxicity which relate to the nature of the substance:

1. Chemical

This relates to specific chemical compounds. The toxicity of such compounds or mixture of compounds is measured in terms of the exposure time needed to cause an effect.