How could toxic mould affect me?

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What causes toxic mould?

Minute mould spores can be detected in the air that we breathe. However, like most organisms they need moisture and nutrients to grow and develop into mould. All types of mould (whether they are toxic or not), need a significant amount of moisture to grow. Mould tends to be more prevalent in environments with high levels of humidity or dampness.

Where is it found?

Mould can be found both indoors and outdoors, typically being spores carried in the air or on shoes, clothing, pets and other items. These spores can then germinate in environments where there is excessive moisture and suitable nutrients. This can include surfaces such as carpets and fabrics, wood, various building products, paper, cardboard and a whole host of other materials. Wet cellulose materials (i.e. cardboard and other paper/wood products and high localised relative humidity (typically above 70%) are reported to be particularly conducive to the growth of a range of moulds.

Buildings with tight structural envelopes and a range of susceptible materials as well as those that remain damp through usage and/or leaks etc. can be more prone to developing mould on relevant internal surfaces.

What are the health implications of exposure to toxic mould?

Currently, there is no authoritative scientific study which clearly demonstrates that exposure to any kind of airborne mould is toxic to human beings, rather the moulds can produce toxins (they can be toxigenic) which then have an effect on us. Certain groups of individuals are more susceptible/sensitive to the effects of mould and these include people who are/have:

  • Very young and the elderly;
  • Immunocompromised;
  • Respiratory conditions;
  • Allergies and asthma; and
  • Skin problems.

Contact through touching or inhaling the mould spores/allergens can trigger allergic reactions or respiratory distress, with symptoms ranging from wheezing, red/itchy eyes and skin and runny or “stuffy” noses to in very extreme cases infections of the respiratory tract and lungs.

Why is toxic mould an issue?

In the US, toxic mould is recognised as affecting people from all walks of life and has resulted in both property and personal injury losses. A Texan family was awarded $32 million after a subsidiary of The Farmers Insurance Group allegedly mishandled a claim for water damage arising as a result of toxic mould, which resulted in their mansion being demolished.  In Delaware, another claimant was awarded $1 million in respect of a mould outbreak which aggravated an asthmatic condition. California is so concerned about toxic mould, that it has brought in legislation requiring anyone selling or leasing property to disclose any potentially dangerous mould problems by its “Toxic Mould Disclosure Act 2001”. If the UK follows the US trend, it is feared that toxic mould could become an increasing insurance issue.

Is there any legislation governing toxic mould?

There is no specific UK legislation governing toxic mould. If toxic mould were detected in your building, it could potentially be classified as a hazardous substance under the Control of Substances Hazardous to Health (COSHH) Regulations. This would mean that the employer would be liable if an employee were exposed to the mould and suffered any ill effects. To comply with the COSHH Regulations, the employer must conduct a suitable and sufficient assessment of risks presented to the staff and identify the steps which need to be taken to prevent any risks to such employees.

Assurity Consulting is the UK's leading independent compliance consultancy specialising in workplace health, safety and environmental solutions. We have over 30 years' experience of helping customers of all sizes, from across all sectors, manage their compliance responsibilities, making sure that their organisation is compliant, their employees are safe, their processes are cost effective and their management team is in control.

This guide is of a general nature; specific advice can be obtained from Assurity Consulting by calling tel. 01403 269375 or by email