Defatting can be prevented by wearing appropriate protective clothing such as gloves, lab coats and aprons when working regularly with defatting agents. Prolonged skin contact or chronic defatting of the skin increases the possibility for developing irritant contact dermatitis and has the potential to worsen pre-existing skin conditions. Patients with chronic dermatitis are advised to use non-irritating soaps and dishwashing liquids sparingly and to choose those with a neutral pH and minimal defatting capability.

Defatting is caused by the exposure of human skin to a chemical substance, including alcohols, detergents, chemical solvents and motor oil. Aliphatic compounds (commonly found in kerosene) cause defatting action, with lower-boiling point aliphatics having the greatest defatting action and therefore the most potential to cause dermatitis. Aromatic compounds, such as styrene also have a defatting capacity.

Chemical irritant contact dermatitis is either acute or chronic, which is usually associated with strong and weak irritants respectively. The following definition is provided by Mathias and Maibach (1978): The mechanism of action varies. Detergents, surfactants, extremes of pH, and organic solvents all directly affecting the barrier properties of the epidermis. These effects include removing fat emulsion, defatting of dermal lipids, inflicting cellular damage on the epithelium, and increasing the transepidermal water loss by damaging the horny layer water-binding mechanisms and damaging the DNA, which causes the layer to thin. Concentrated irritants have an acute effect, but this is not as common as the accumulative, chronic effect of irritants whose deleterious effects build up with subsequent doses (ESCD 2006).

Chemical irritants are often strong alkalis as found in drain cleaners and soap with lye residues. Many other chemical compounds can also cause contact dermatitiis.

Irritant contact dermatitis is a form of contact dermatitis that can be divided into forms caused by chemical irritants and those caused by physical irritants.