Chemical and Biological Health Hazards and Risk Control

Introduction to Chemical And Biological Health Hazards

Did you know that each year considerably more people suffer from work related ill health incidents, exacerbated through working with hazardous substances. Some of these illnesses in extreme cases can cause fatality, however more commonly they lead to illnesses such as skin sensitisation and respiratory disease. It is estimated that within the UK 30% of all cancers have an occupational link. This article intends to introduce you to Chemical and Biological Health Hazards and Risk Control. The Regulation which support this article are Control of Substances Hazardous to Health (COSHH), further guidance and information is available here.

Chemical Agents

Chemicals can be transported by numerous agents and using many forms. Here is a brief description of the main types of chemical agents present in the workplace and further down the page Chemical and Biological Health Hazards and Risk Control.

Dusts – Have you considered the hazard of dust within your workplace? Are your people being exposed to dust through their normal work activities, or does your work activity generate dust which could be a hazard for others? Dust are solid particles that are suspended in the air for a period of time depending upon the weight of the particle will determine the time it is suspended in the air. The dust particles can vary in size from around 0.4mm up to 10mm, these are categorised as fine and course respectively. We create dust through mechanical and construction processes or through other specific tasks such as waste handling. An example that we recently came across was a waste operative being exposed to dust from waste when an employee opened up a large container and a gust of wind entered and disturbed the dust causing it to become airborne, the employee breathed the dust in as their normal work activity did not require any Respiratory Protection Equipment (RPE). The employee became ill and was away from work for two weeks due to that illness. The small fine dust particles are considered more hazardous due to the fact that they can penetrate the bodies natural defences and affect our lungs, this is known as respirable dust, and in some circumstances this dust can even enter our blood and cause damage to our organs. Some examples of these fine dusts are cement and silica dust. Repeated exposure may lead to long term chronic ill health such as lung disease.

Gases– Substances which are present at a temperature above their boiling point, steam is a gaseous form of water. Gases are absorbed into our bloodstream and may cause harm such as carbon monoxide.

Vapours – We recently had a client who engaged us to carryout some health and safety work, during the course of the morning the business owner complained that her headaches had returned after a holiday where she experienced no headaches. After initial investigation it was discovered that the premises used a hazardous substance that gave off vapours that were flammable. It was highlighted to the client that hazardous substances must be controlled and exposure to this vapour could have been the cause of headaches. Controls were implemented and the client gave us feedback a couple of weeks after the work that her headaches had subsided and everyone within the premises was feeling healthier than before the controls were in put in place. Vapours are substances which are close to their boiling point, they are gaseous in form. The vapours if inhaled, enter our bloodstream and may cause short term ill health effects such as drowsiness and dizziness. They are also capable of causing long term ill health effects such as brain damage.

Liquids – Substances which usually exist at temperatures between their freezing and boiling points. Often referred to as fluids in health and safety legislation. An example of a hazardous liquid is some vaping liquids and bleach, even furniture polish carried a hazard warning symbol.

Mists – Substances that are similar to vapours but are closer to liquids, as such they are small liquid droplets suspended in vapour. Mists can be produced during a car spray paint task. A recent visit to a local aircraft engineering plant highlighted the importance of isolation and ventilation when dealing with mists. The mist hazard was present within their spray painting facility. Most industrial mists can be dangerous when inhaled and produce similar effects to vapours. It is possible for mists to enter our body through inhalation and absorption.

Fumes – This substance is a collection of tiny metallic particles which have condensed from the gaseous state. they are less than 1mm in diameter. Fumes can be generated from welding activity and the particles tend to be within the fine respirable range which is 0.4mm up to 1mm which may lead to long term ill health effects such as permanent lung damage. The nature of harm will depend upon the duration of exposure and what substance is in use. It is a constant source of both joy and sadness when we can prevent exposure to such hazards as hazardous fumes because we are happy that they have been suitably controlled, however prior to intervention people have been exposed to them and may suffer ill health effects. This is where health surveillance will play a vital part in early detection and monitoring of those effects. Health surveillance will be covered in another section of our blog.

Biological Agents

We have looked briefly at chemical agents and biological hazards can be transported by numerous forms of agent such as:

Fungi – These are small organisms which can appear as plant like such as a mushroom. However unlike plants, they are unable to produce their own food and live off organic matter, animals, plants and parasites. Fungi reproduce using spores, which may cause allergic reaction when inhaled. Fungal infections can range from minor to severe and are usually treated with antibiotics. All mushroom varieties are fungi, most are not harmful, so it is still a staple on our plate when shop purchased.

Moulds – These are a small group of fungi which under damp conditions grow on surfaces such as walls and foods such as cheese. Some mould is beneficial such as penicillin or may cause harm by infecting our lungs (Farmers Lung) and may lead to asthma. Farmers lung is contracted from breathing in mould spores, hay dust and animal grain dust. The breathing in of mould spores can be controlled through the use of ventilation systems, using effective filters in vehicles and equipment. Also consider changing to a low dust content material such as a pellet and consider using safer substances which can substitute the substance in use.

Bacteria – These are small organisms . they can live outside of our body. They are controlled through the use of antibiotics. Not all bacteria is harmful to humans, it is bacteria which helps us to break down food during digestion. However harmful Bacteria such as legionnaires, tuberculosis and tetanus can cause severe and even fatal harm. Bacteria can be controlled through temperature and filtration.

Viruses – These are tiny non-cellular organisms. Smaller than bacteria and cannot be controlled by antibiotics. New virus strains are continually developing. They can be treated and defeated by the human bodies natural defences and healing system. Medication can be used to treat the symptoms but are unable to cure it. The HIV virus spreads AIDS. The common cold is a viral infection and unfortunately the Corona virus fits into this section.

Classification of Hazardous Substances and Associated Risks to health

A hazardous substance can cause ill health to persons at work such as certain paints and fumes or naturally occurring such as dusts. Hazardous substances are classified according to the severity and type of hazard they present when a person comes into contact with them. Here are the 5 most common classifications:

Irritant – A non-corrosive substance which is capable of causing skin and lung inflammation after contact. A person who reacts to an irritant are sensitised or allergic to that substance. Many household substances such as detergent, bleach and glue are irritants.

Corrosive – Substances which cause harm usually through burning of living tissue. Strong acids and alkali such as sulphuric acid and caustic soda, oven cleaning products are corrosives.

Harmful – This is the most common classification and describes a substance which if a person has contact through ingestion, inhalation and absorption it may pose a limited health risk. Many household substances fall into this category.

Toxic – These substances impede or prevent body function of one or more organs within our body, such as kidney and liver. A toxic substance is a poisonous substance. The health effects on a person is dependent upon the concentration and toxicity of the substance and the exposure time and frequency of exposure. Also the effectiveness of any controls in place will be taken into account.

Carcinogenic – These are substances that are known or are suspected of effecting normal development of body cells which could lead to cancers. Asbestos and creosote are carcinogenic and it is vital to follow any precautions when using these types of substance.

Mutagenic – Anything that causes a mutation (a change in the DNA of a cell). DNA changes caused by mutagens may harm cells and cause certain diseases, such as cancer. Examples of mutagens include radioactive substances, x-rays, ultraviolet radiation, and certain chemicals. The effects on human health may be acute which are short in duration and appear rapidly after exposure. Chronic effects develop over a period of time which could be many years after exposure. Chronic ill health effects are caused by prolonged or repeated exposure to a hazardous substance, which could result in illness which could remain undetected for many years. Many cancers fall into the chronic catergory and an individual may experience no symptoms during the development stage of illness.

Hazard Statements

Hazard Statements (H-Statements) are part of the Globally Harmonised System of Classification and Labelling of Chemicals (GHS). Hazard statements provide standardised wording to indicate the hazards of a product including, when appropriate, the degree of the hazard. A hazard statement is a phrase that describes the nature of the hazard in the substance or mixture. A hazard statement will be determined by the application of the classification criteria. Examples of hazard statements include: Causes serious eye damage. Toxic if swallowed.

Routes of Entry into the Body of Hazardous Substances

Inhalation- This is where a hazardous substance enters through normal breathing activity. This is the most common route of entry and the substances can be chemical, biological such as bacterial and fungi. They enter the lungs and gain access to our blood stream and organs.

Absorption – This is where a substance can enter our body through the pores in our skin or through a wound.

Ingestion – The substance enters our body through the mouth and swallowed into our stomach and digestive system. Poor hand hygiene is a major factor when considering this method of entry.

Injection/ Puncture – This is where a substance enters our body through injection and or puncture such as a needle stick from a discarded syringe or injury from equipment that may inject a hazardous substance into the body through the wound.

COSHH Regulations

The COSHH regulations are a comprehensive and significant piece of legislation focused upon Chemical And Biological Health Hazards and will be covered separately in one of our articles which can be found here.

Further Reading

If you are interested in hazardous substances and who wouldn’t be! here is a book which will offer you an in-depth insight about information that is covered and assessed for the NEBOSH Diploma.