The invisible mould in your garden that can threaten your respiratory health

Gardening · Published 3 October 2026 Swipe more like this →

In short: You likely encounter Aspergillus mould daily in soil, compost, and rotting leaves. While harmless to most, this common fungus can trigger serious lung conditions in vulnerable individuals. Understanding how to manage your exposure is essential for those with weakened immune systems or existing respiratory issues like asthma or COPD.

Aspergillosis refers to a group of conditions caused by the Aspergillus mould. This fungus is ubiquitous in the environment, thriving in common locations such as compost heaps, piles of dead leaves, dust, and even damp buildings or air conditioning systems. For the vast majority of healthy people, breathing in these microscopic spores causes no illness. However, the risk profile shifts significantly for individuals with pre-existing lung conditions, such as cystic fibrosis, asthma, or chronic obstructive pulmonary disease. Those who have previously suffered from tuberculosis, severe influenza, or COVID-19 requiring artificial ventilation are also at heightened risk, as are individuals with weakened immune systems due to chemotherapy or organ transplants.

The clinical presentation of aspergillosis varies, ranging from allergic reactions to chronic infections or life-threatening invasive disease. Symptoms often include a persistent cough, shortness of breath, wheezing, and fever. Because these symptoms can mimic other chest infections, diagnosis often requires specialized testing, including X-rays, blood analysis, or a bronchoscopy. If left unmanaged, the infection can cause lasting damage to lung tissue. Treatment strategies are highly specific to the condition's severity, involving everything from steroid and antifungal medications to surgical intervention for removing fungal balls known as aspergillomas.

While it is nearly impossible to eliminate exposure to Aspergillus entirely, targeted preventative measures can significantly lower risk for those susceptible. Experts recommend avoiding high-risk environments like compost piles and dusty areas, or wearing a face mask when gardening. Maintaining a healthy home environment is equally critical; this includes using dehumidifiers, employing HEPA-filtered air purifiers, and keeping indoor temperatures between 18 and 21 degrees Celsius. Simple habits, such as airing out rooms regularly and avoiding drying laundry in living spaces, further reduce the likelihood of mould accumulation. For those with chronic lung conditions, vigilance regarding worsening symptoms is the primary defense against long-term respiratory complications.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

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