Types of skin diseases - Dermatitis

What is Work-Related Contact Dermatitis?

Work-related contact dermatitis, (sometimes called eczema) can be caused by the skin coming into contact with:

• chemicals;
• frequent contact with water (eg more than two hours a day);
• biological agents (eg plants, bacteria and fungi);
• physical agents (eg vibration, UV radiation); and
• mechanical abrasion (eg abrasive substances such as sand and rough edged surfaces and tools).

Contact dermatitis

As the term implies, contact dermatitis is a disease resulting from skin coming into contact with an outside agent. These agents can be chemical, biological or physical in nature. There are two types of contact dermatitis associated with skin exposure to chemicals: Irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD).

The signs of contact dermatitis include redness, swelling, blistering, flaking and cracking. It can lead to itching, bleeding and puss formation.

Irritant contact dermatitis (ICD)

ICD is a local inflammation of the skin. It can develop after a short heavy single exposure (acute) or be due to repeated and prolonged exposure (chronic) to hazardous agents, including chemicals. In some cases, more than one agent will be involved, for example water and detergents. The irritant action of a chemical depends on its ability to cause changes to the horny (outside) layer of the skin. Some substances can remove skin oils, fats and moisture from the surface. This action reduces the protective action of the skin and increases the ability of the irritant substance to enter or infiltrate the skin.

Allergic contact dermatitis (ACD)

ACD develops in stages. The allergic reaction begins with a process called sensitisation. Sensitisation starts when an allergic substance (eg chromium in cement) penetrates the skin. This provokes a number of immunological responses. The process can last from four days to three weeks.

When a sensitised person is re-exposed to an allergenic substance, white blood cells recognise it and react to protect the body. But they also release chemicals called lymphokines. These cause itching, pain, redness, swelling and blisters on the skin. Once sensitised, the allergic reaction is likely to remain with the individual for life. If further contact is prevented, the level of sensitivity may gradually decline.

Occupations affected by contact dermatitis

It affects most industries and business sectors:

These are the business sectors with the highest risk of work-related dermatitis. But remember, dermatitis can affect people working in all sectors.