The mechanism of development of the lesion may be divided into three phases:
Skin or eye contact occurs when the chemical product is splashed on the skin or in the eye. Contact with the digestive tract ( mouth, oesophagus, stomach) occurs when the chemical product is swallowed. In the case of the airways, it takes place when vapours of the chemical product are inhaled.
Once the product is in contact with the tissue, it may penetrate the tissue, in spite of the biological barriers. The characteristics of the chemical product define its penetration potential and penetration rate into tissue.
The chemical product will penetrate into tissue until it encounters a biological constituent with which it can react. The penetration depth of the chemical product into the tissue before it reacts therefore depends on its type.
Once the chemical product has reached the biological constituent of the target tissue, the chemical reaction takes place. The biological equilibrium is changed, the tissue is locally destroyed and the lesion forms.
The lesion therefore only develops during the chemical reaction, once the chemical product has reached its target. Each splash of chemical product contains a very large number of molecules capable of reacting with a target molecule or with a target cell of the human body.
Rapid intervention following contact makes it possible to restrict the extent of the lesion:
Emergency decontamination is paramount.
The type, depth and severity of the lesion depend on many factors: