Common hazardous substance hazards - Hazardous substances - Healthy Working Lives

Hazardous substances

Identifying hazardous substances and steps you can take improve safety

Those exposed for long periods of time are generally more at risk than those exposed for short periods or to less hazardous substances.

Use the links below to find information and resources to help you identify the risk to employees and the precautions you can take. 

  1. Common hazardous substance hazards
  2. Hazardous substance safety precautions

1. Common hazardous substance hazards

Hazardous substances can include

  • biological agents - such as fungi, bacteria, viruses
  • natural substances - such as grain, flour or enzyme dusts
  • substances generated by work - such as soldering or welding fumes, or wood dust
  • chemical products used or produced at work - such as adhesives or cleaning agents.

These can be present in your workplace from a variety of sources, including

  • gas - such as chlorine or carbon monoxide
  • liquid - such as degreasing solvent or cleaning chemicals
  • spray or mist - such as paint and epoxy sprays and acid mists
  • fumes - such as welding, hot rubber, soldering, galvanising fumes
  • vapour - such as solvent vapour released from adhesives, paints or inks
  • dust, powder or paste - such as wood, cement, metal, flour, grain, rubber or stone dust.

The video below can be used and shared with your employees to help raise awareness and encourage discussion on the hazardous substances. 

Workplace Exposure Limits (WELs)

Hazardous substances can have an effect when they come into contact with the human body. Many of these substances will carry WELs. Exposure to substances can occur through

  • ingestion
  • contact with the skin
  • breathing in substance
  • injection through a puncture in the skin.

You can find out more ab​out WELs on the Health and Safety Executive (HSE) website.

Visit the HSE site for guidance on WELs

Skin contact

Direct skin contact from using a substance can happen through

  • using a product
  • accidental contact such as a splash
  • inadvertent contact such as using a cloth with a substance already on it.

This can result in

  • burns
  • dermatitis
  • skin cancers
  • eye damage.

Other forms of contact

Damage to the body also comes from inhalation, injection or ingestion of the substance which can result in

  • bronchitis
  • lung cancers
  • airway obstruction
  • lung diseases such as asthma.

Or damage to internal organs causing

  • nervous system diseases
  • cancer in other parts of the body
  • disorders of reproductive organs.

Who is at risk?

Workers can be exposed to hazardous substances depending on their work activity. Examples are provided below.

  • Hairdressers, through hairdressing products that can damage skin and lungs.
  • Healthcare, animal care and agricultural staff, through exposure to biological agents.
  • Cleaners, through cleaning materials that cause localised burns and skin complaints.
  • Bakery workers, through flour dust that causes irritation of eyes and nose, skin problems and asthma.
  • Welders, garage and engineering workers, through paints, solvents, oils and grease, exhausts and other fumes.
  • Construction trades workers, through exposed to fumes and dusts and specific hazards such as lead and asbestos.

The Control of Substances Hazardous to Health Regulations (COSHH) place duties on you to take measures to prevent or control the exposure. There are also specific regulations relating to lead and asbestos.

Carry out a risk assessment

To help identify if there could be a hazard, you need to consider if any products you use have danger labels or signs. For example

  • toxic
  • irritant
  • harmful
  • corrosive
  • very toxic.

You also need to consider if any of the products you use

  • have safety data sheets or other warnings
  • gives off dust, mist, spray, splashes, fumes, smoke or gases
  • have safety information in your trade association or trade magazine
  • have people coming into contact with it by touch, breathing it in or ingesting it.

Your workplace risk ​assessment​ should identify if hazardous substances are used or generated in the workplace. 

Find out how to carry out a risk assessment

COSHH assessment

You may then need to carry out a more specific assessment of the risk posed to workers and the controls you will need to put in place to protect them. This is known as a COSHH assessment.

We have created a publication with guidance and a form to help you carry out a COSHH assessment.

Go to our COSHH assessment publication

​Find out more

The HSE site has further information and guidance including hazardous substances at work and COSHH Essentials .