Why drying clothes indoors could put your health at risk

Analysis: Drying wet clothing indoors in poorly ventilated spaces could increase the amount of mould growing in your home

By Rebecca A. Drummond, University of Birmingham

Hanging the washing out to dry in the garden has been a rare sight these last few months, with winter storms bringing freezing temperatures and 100mph gusts of wind. But does the way we dry our clothes indoors actually matter?

Drying wet clothing on racks in poorly ventilated spaces could increase the amount of mould growing in your home, which is associated with poor health and, in some cases, even death. When mould grows in your home, it can form black or green coloured patches on the walls, and usually creates an unpleasant musty smell. It shouldn’t be ignored, because being exposed to mould over long periods of time can have serious health implications.

We need your consent to load this rte-player contentWe use rte-player to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences

From RTÉ Radio 1’s Today with Claire Byrne, home economist and lecturer at TUS Agnes Bouchier- Hayes on using tumble dryers to dry clothes

Mould is a broad term for a group of fungi that produce tiny particles called spores. Fungi produce spores when conditions are right for their growth, which can include cooler temperatures and high humidity. This is why you’re more likely to find mould growing on bathroom ceilings or damp walls, where there is more water for fungal spores to settle and grow.

There are many different species of mould. The most common ones to cause problems in damp homes are penicillium and aspergillus. It’s estimated that we breathe in small numbers of spores from these fungi on a daily basis.

Luckily, our immune system is very good at spotting and killing fungal spores, which limits the number of fungal lung infections in humans even though we’re constantly exposed. Immune cells called macrophages sit inside the air spaces of the lungs (called alveoli), and these cells eat anything you inhale that could be considered harmful, including fungal spores.

We need your consent to load this rte-player contentWe use rte-player to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences

From RTÉ Radio 1’s Morning Ireland, ‘It’s really tough’: Dublin tenants talk about struggling with mould in their homes

Risks for compromised immune systems

However, there are many people whose immune systems are not able to remove fungal spores, and in these cases the fungi can cause dangerous infections or make underlying health conditions (such as asthma) much worse.

People who have damaged or compromised immune systems are at higher risk of becoming seriously unwell from fungal infections. Moulds like aspergillus cause infections in patients with limited immune function, or who have lung damage from diseases like asthma, cystic fibrosis and chronic obstructive pulmonary disease (COPD) associated with heavy smoking.

In people with asthma, the immune system overreacts to triggers (including fungal spores) causing inflammation in the lung. This inflammation makes it more difficult to breathe by reducing the size of the airways. The same type of immune response is responsible for the symptoms of asthma and allergic responses, and fungal spores can also trigger these same types of immune responses. This means that fungal spores can be a particularly powerful trigger for some people.

We need your consent to load this rte-player contentWe use rte-player to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences

From RTÉ Radio 1’s Today with Claire Byrne, Prof Stanley Miller from COPD Support Ireland on how to live well with COPD

In very extreme cases, the fungal spores don’t just cause inflammation but can invade the airways and block them leading to bleeding within the lung. This happens when spores germinate and form long spiderweb-like projections called mycelium which create sticky lumps that block airways and damage the delicate tissues of the lung.

Growing resistance

Aspergillus infections are treated with antifungal drugs called azoles, which prevent the fungal cells from forming properly. Azoles are very effective, but there are increasing rates of resistance to azoles reported in aspergillus which is a significant cause for concern.

We have a limited range of antifungal drugs available to treat mould infections – and when resistance develops this can severely reduce the options a patient has for treatment. Resistance to drugs such as azoles can develop in patients who take these drugs for long periods of time, but recent research has indicated that resistance is more commonly developing in the environment, where most fungi are found. This means that even before a patient is diagnosed with an aspergillus infection, it may already be too late for the antifungal drugs to be effective.

We need your consent to load this facebook-post contentWe use facebook-post to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences

Development of drug resistance in environmental fungi has been linked to use of azoles and other antifungal drugs in farming. Fungal infections are a big problem for crops, and plants need protection from these infections the same way we do. Unfortunately, the same drugs we use in the clinic are the same types that are being used in agriculture.

Climate change may also be driving drug resistance in environmental fungi. Exposure to high temperatures was recently found to help moulds develop resistance to commonly prescribed antifungal drugs. There have also been reports of patients becoming ill from species of mould that were not thought to cause human disease, in part because they could not grow at the human body temperature.

More mould species could therefore be picking up the ability to cause infections, as well as becoming drug resistant. Research programs and healthcare initiatives that monitor for these changes are vital to help us become prepared for potential increases in mould infections.

READ: 6 hacks for drying laundry without using a tumble dryer

While a healthy immune system means that typical exposure to fungal spores is not likely to cause you any health problems, being exposed to very large amounts of fungal spores can prove to be fatal even for people who don’t have underlying health issues.

It’s important, then, to help keep your home free of mould. The best way to do this is ensure you have good ventilation and take other measures to reduce damp, such as using a dehumidifier or investing in a heated clothes rack to dry your clothes indoors in the winter.

Rebecca A. Drummond is Associate Professor, Immunology and Immunotherapy at the University of Birmingham. This article was originally published by The Conversation

Follow RTÉ Brainstorm on WhatsApp and Instagram for more stories and updates

The views expressed here are those of the author and do not represent or reflect the views of RTÉ