August 27, 2017

HSE Corner: Working with Hazardous Substances


Every year, thousands of workers are made ill by hazardous substances, contracting lung disease such as asthma, cancer and skin disease such as dermatitis.

These diseases cost countries many millions of dollars each year. As the employer, you are responsible for taking effective measures to control exposure and protect health. These measures can also improve production or cut waste.


Looking after your business

Your aim in running your business is to make a profit. You know what you do, and how you are doing it. You know what ‘processes’ and ‘tasks’ are involved. You know the shortcuts. Ensuring your workers remain healthy may also lead to healthy profits.


Which substances are harmful?

  • Dusty or fume-laden air can cause lung diseases, e.g. in Jewellery manufacturing or woodworking.
  • Metalworking fluids can grow bacteria and fungi which cause dermatitis and asthma.
  • Flowers, bulbs, fruits and vegetables can cause dermatitis.
  • Wet working, e.g. catering and cleaning, can cause dermatitis.
  • Prolonged contact with wet cement in construction can lead to chemical burns and/or dermatitis.
  • Benzene in crude oil can cause leukaemia.

Many other products or substances used at work can be harmful, such as paint, ink, glue, lubricant, detergent and beauty products. Many substances can harm health but, if used properly, they almost never do.

Substances can also have other dangerous properties. They may be flammable, for example, solvent-based products may give off flammable vapour. Clouds of dust from everyday materials, such as wood dust or flour, can explode if ignited.


In what way are they harmful?

You can find out by:

  • Checking information that came with the product, e.g. a material safety data sheet (MSDS);
  • Asking the supplier or sales representative;
  • Checking on the Internet.


Exposure to hazardous substances

You can be exposed to hazardous substances in different ways:

  • Breathing in gases, fumes, mist or dust
  • Contact with the skin
  • Swallowing
  • Contact with the eyes
  • Skin puncture


Exposure by breathing in

Once breathed in, some substances can attack the nose, throat or lungs while others get into the body through the lungs and harm other parts of the body, e.g. the liver.


Exposure by skin contact

Some substances damage skin, while others pass through it and damage other parts of the body.

Skin gets contaminated:

  • By direct contact with the substance, e.g. if you touch it or dip your hands in it
  • By splashing
  • By substances landing on the skin, e.g. airborne dust
  • By contact with contaminated surfaces – this includes contact with contamination inside protective gloves


Exposure by swallowing

People transfer chemicals from their hands to their mouths by eating, smoking…etc. without washing first.


Exposure to the eyes

Some vapours, gases and dusts are irritating to eyes. Caustic fluid splashes can damage eyesight permanently.


Exposure by skin puncture

Risks from skin puncture such as butchery or needle stick injuries are rare, but can involve infections or very harmful substances, e.g. drugs.


Assessing risk

Risk assessment is not just a paper exercise. It’s about taking sensible steps to prevent ill health. You need to know how workers are exposed, and to how much, before you can decide if you need to do anything to reduce their exposure.

Sometimes, it’s easy to judge the amount of exposure to substances and decide what you can do about it.


For more information on hazardous substances or any HSE issues, please contact

Topics: Health, Safety & Environment (HSE)

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