Could there be legionella risk in your garden?

Author: Charlie Brain, senior consultant, Water Hygiene Centre

In today’s world people are trying to save money, lead healthier lifestyles, eat healthier foods and be more active. Many people take pride in their gardens and use gardening to help with healthier lifestyles by growing their own healthy foods and enjoying the fresh smell of flowers.

Can gardening equipment harbour legionella?

Leading up to the summer months, many gardeners think about saving rainwater for their garden’s thirstiest months. It is a little-known issue, but neglect and misuse of our gardening equipment can represent health risks in the form of waterborne bacteria and diseases. Water butts, hose pipes, ponds and even compost can all harbour harmful levels of bacteria if not looked after correctly. 

In this blog, we look at some of the issues with gardening equipment and other devices used or found in the garden and what might be done to reduce the risk of exposure to soil and waterborne bacteria.

Why is it important to regularly maintain your gardening equipment?

There is a plethora of soil and waterborne bacteria, one type of bacteria is ‘legionella’. Exposure to legionella can cause legionnaires’ disease. In recent times, there have been reported cases of legionnaires’ disease linked with gardening activities, for example:

• Between 2008 and 2013, 16 people in Scotland contracted legionnaires’ disease from compost. 2 of these cases were fatal.
• A 63-year-old gardener from Norfolk contracted legionnaires’ disease and sadly died, they had been exposed to the Legionella after using a hose pipe.
• RHS - Minimising health risk in the garden.
• The Times - Gardeners using water butts risk spreading legionella germ.
• The Guardian - Dr Dillner's health dilemmas: can you catch legionella when gardening?
• The Telegraph - Hygiene warning to gardeners after study finds legionella in compost.

Articles like these demonstrate the potentially catastrophic consequences of failing to properly manage and understand the risk of legionella bacteria. Making sure the public is aware of legionella risk and the control measures available will go a long way to potentially reducing the risks they may be exposing themselves to whilst enjoying their gardens.

What types of legionella can be found in gardening equipment?

With all gardening-related activities there are 2 types of legionella bacteria that have been reported within the UK;

1. Legionella longbeachae – This is not common but can be found in potting mixes, compost heaps and composted animal manures. Respiratory disease can develop after inhaling dust from contaminated compost.
2. Legionella pneumophila – This is more common as the bacteria forms naturally in watercourses but will multiply in purpose-built water systems. Where these systems are allowed to stagnate or are slow moving, where sediment and scale are present, and where temperature of the water is between 20°C to 45°C, provides ideal conditions for waterborne pathogens to proliferate. Inhalation of water aerosols (sprays) is the route of infection. The source of which can be hoses or sprinklers, outside taps, hot tubs and water features or fountains. This type of bacteria accounts for 90% of legionella cases in the UK. 

Who is most at risk from legionella?

The health and safety executive (HSE) have defined those with increased susceptibility to developing an illness caused by legionella bacteria as:

• People over 45 years of age;
• Smokers and heavy drinkers;
• People suffering from chronic respiratory or kidney disease;
• Diabetes, lung and heart disease;
• Anyone with an impaired immune system.

The UK population is approximately 67 million, of which approximately 27 million people partake in gardening. What is the demographic of these gardeners? Many sources state that the typical gardener is female, aged 55 and over. The latter is most pertinent here when looking at susceptibility.

Conclusion

Gardeners should be aware of potential risks associated with gardening equipment, devices found or used in the garden. 

Like any product, individuals should ‘always read the label’ for advice how to operate, maintain and minimise any legionella risks created by them, for example warning label on the side of bags of compost. 

Landlords and dutyholders should also undertake a legionella risk assessment to help minimise the potential risk. By increasing awareness of these risks and sharing of information we can all help to reduce the amount of exposure to legionella, and beat the micro beasties lurking in our gardens!

The following blog post is for informational purposes only and should not be considered professional or legal advice. The views and opinions expressed in this post are those of the author and do not reflect the official policy or position of the National Association of Local Councils. Any links to external sources included in this blog post are provided for convenience and do not constitute endorsement or approval of those websites' content, products, services, or policies. Therefore, readers should use discretion and judgment when applying the information to their circumstances. Finally, this blog post may be updated or revised without notice.