Occupational and environmental skin disease
The lungs and skin (as well as the nose and eyes) are the organs of first contact for most environmental exposures (excluding ingestion). This page complements other modes of learning about the skin's health in relation to occupational and environmental hazards.
Relevant fundamentals of skin structure and function
The skin is not an absolutely impermeable membrane. It consists of a layer of horny dead cells overlying living (and very vulnerable) ones. It is fairly impermeable to water splashes but continuous immersion in water with friction will macerate it. Organic fat solvents can go through the skin fairly quickly.
Inorganic caustics (strongly alkaline compounds) will damage the skin very readily by sparifying fat and hydrolysing protein. The skin has a very good capacity to regenerate provided the deepest layers are not irretrievably damaged. However while it is still damaged and not yet fully healed it remains vulnerable to damage and can be made worse by many agents which the normal skin could easily have withstood.
Health effects on the skin
Acute corrosion
Obviously strong caustics, acids or similar substances will corrode the skin severely.
Dermatitis
By far the commonest (but not the only) health effect on the skin from environmental agents is dermatitis (which can be considered synonymous with eczema) although this can also arise from non-environmental causes. Dermatitis simply means inflammation of the skin. Irritant dermatitis is caused by defatting agents (e.g. solvents, caustics), acids, or even salt(s) besides a variety of other substances. Can likewise be caused by a wide variety of agents, e.g. rubber or many substances used in its manufacture, several other plant products, dyes, insecticides, etc.
Urticaria
This is another form of usually allergic skin disease, which is often termed hives or nettle rash. Occupational urticaria, when allergic is mediated by a type I mechanism like many instances of occupational asthma (Agius website), with which it can coexist. For example latex or laboratory animal allergy can cause both asthma and urticaria, both as a result of sensitisation (Agius website). This combination may be a herald of serious anaphylactic shock and angio-oedema. In some instances it is mediated by non-immune mechanisms, perhaps as a direct manifestation of mast cell activation.
Acne
This can be caused by exposure to dioxin(s) even in low concentrations, or chlorinated organic solvents or mineral oils if the exposure is high enough.
Other toxic effects
Vesicant effects (blistering)
Various other types of toxic effects can result from skin exposure to chemicals.
For example some substances with 'alkylating' properties, e.g. 'mustard' compounds and some alkyl organometallic compounds can produce severe blistering of the skin.
The way to avoid this sort of occurrence cannot simply be to 'ban' such hazardous substances since they in specific circumstances (such as cancer treatment) they have an important beneficial role. The answer must be in appropriate control at source, protection, education and work practice to ensure that occupational exposure to the skin or in other ways does not occur.
Disorders of pigmentation
Chemical agents such as para tertiary butyl phenol can cause a depigmentation called vitiligo. (This is because in their chemical structure they resemble the amino acid tyrosine which is a precursor of the skin pigment melanin.)
Cancer
Substances containing polycyclic aromatic hydrocarbons, such as occur in pitch, tar and oil can cause skin cancer. This can also be caused environmentally or occupationally by inorganic compounds of arsenic.