How can Hazardous Substances affect workers?

Inhalation: Dust, fumes or aerosols in the air can easily be breathed in. This can cause damage to the nose, upper respiratory tract and lungs. It is also the most efficient way of absorbing chemicals into the blood stream.

Skin Contact: Hazardous substances that come into contact with the skin can damage the skin itself causing burns or dermatitis.
Some substances can trigger an allergic reaction. Others can be absorbed through the skin to affect other organs in the body.

Ingestion: Finally people can swallow hazardous substances. In a workplace setting this is usually less of a risk than inhalation or skin contact. However, it can happen. For example, poor hygiene practices could mean that workers hands are contaminated when they take a meal break.

Generally the effects on health include:

Acute Effects: Immediate effects such as irritation, burns, shortness of breath are called acute effects. They are often easy to spot and the need to control the chemical that causes them may be fairly obvious. For example, it is well known that sodium hydroxide solution is caustic so the need to protect against exposure when using it as cleaning product is clear.

Chronic Effects: Longer term damage such as cancer, or liver damage are called chronic effects. It is also possible for an acute problem such as dermatitis to develop into a chronic problem if there is repeated exposure over a period of time. Chronic effects may often be much more difficult to recognize.