Is Mould Dangerous? The Effects of Household Mould

Is Mould Dangerous? The Effects of Household Mould

Feb 07, 2024Richard Weager | Greenshop Paints

Have you ever spotted a suspicious patch of grey or black on your walls and felt that knot in your stomach as you realise it’s mould? You're not alone. 

As someone who's tackled mould head-on in my own cottage, I understand the anxiety it can cause. However, it’s important to tackle mould straight away no matter how small, as it can become a silent home invader often unnoticed until it becomes unsightly and problematic. 

In this comprehensive article, we'll explore the true impact of mould. Whether you're dealing with a small patch or a widespread problem. Learning about the risks of mould is the first step to understanding the potential impact it can have on your home. 

So, take a deep breath (mould-free, hopefully!) and let's dive into the world of mould.

How Harmful Can Mould Be to Your Health, Home, and Finances?

Mould can be a silent predator affecting your health, home and eventually your finances. From my personal experience, I've seen first-hand how it can rapidly transform a vibrant living space into a health hazard. 


Mould exposure, particularly over prolonged periods, can lead to a range of health issues. These can include: respiratory problems, allergies, skin conditions, eye irritation, headaches, nausea and even mould poisoning in extreme cases.

Respiratory - conditions like asthma can be exacerbated or triggered by mould spores, which can bring on severe asthma attacks. People with a weakened immune system are at a higher risk of developing respiratory diseases like bronchitis and pneumonia. It can also cause new respiratory issues such as wheezing and coughing.

Allergies - It is relatively common for tiny mould spores to trigger an allergic reaction when inhaled, irritating your nose, throat, and lungs. This can also cause redness, itchiness and conjunctivitis in the eyes, a runny nose and sneezing. In my case, my mild allergies became significantly worse until I identified and removed the mould in my cottage.

Skin problems - skin conditions can also be triggered by excessive mould in the home, including eczema and dermatitis.

Lastly, in worst but rare cases, mould exposure can lead to a serious illness called mould poisoning. Symptoms of mould poisoning can include fever, chills, muscle aches, and respiratory problems. If you experience these symptoms in a mould infested home, it's important you seek out medical advice immediately.

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The impact of mould extends beyond just aesthetics. Mould can penetrate deep into various materials, including silicone, paint, plaster, wallpaper, wood and fabrics. Once mould has penetrated below the surface, it becomes much harder to get rid of as it keeps growing back.


Many people make the mistake of wiping the walls and painting over the area with fresh paint. Unfortunately, mould will continue to grow underneath and will eventually bubble/blister the paint until it flakes away. Ideally, once the area has been treated effectively with a professional mould remover, you would apply a coat of anti mould paint to reduce the chances of any mould resurfacing.



Mould causing structural damage and rotting floorboards after a leak

Finally, if you leave mould treatment too late it can become very costly. Costs can include replacing plasterboard, furniture, bathroom seals/grouting and possibly hiring professional mould removal specialists (depending on the level of infestation). Lastly, you will still be left with the damage left behind and the costs of re-decorating.


It's important that mould is dealt with quickly and effectively to reduce the financial impact it can cause. A small financial outlay now can save you from much bigger costs further down the line.  Mould also has a devastating effect on the value of your property and your ability to sell. It's a lesson many homeowners learn the hard way: prevention and early action are far more cost-effective than delayed repairs.


Are Certain Types of Mould More Dangerous Than Others?

There are over 100,000 different species of mould and the most common way people identify mould and its perceived level of danger is by its colour. However, a single colour like black or green doesn’t signify one type of mould. There are actually thousands of species of mould that can present in various different colours throughout their lifespan, each with varying effects on our wellbeing.

The colour of mould gives almost zero indication of the risks associated with it. We have come across a vast array of mould colours in our time, from the common black and green, to pink, purple and orange.

Regarding the danger elements, mould types are often grouped into one of three categories based on their level of potential health risks:


Allergenic Moulds (Low Risk) 

These trigger reactions with people affected by mould allergies or asthma. Roughly 10-15% of children and 26% of adults in the UK suffer with this and the most common allergenic moulds include: Alternaria, Aspergillus, Cladosporium and Penicillium.


Pathogenic Moulds (Low Risk)  

Pathogenic moulds are capable of causing infections and diseases in humans and other organisms. They are particularly dangerous to those with weak immune systems, commonly affecting infants, the elderly and cancer or transplant patients. Most healthy people with good immune systems will be able to fight off pathogenic moulds.

The most common pathogenic moulds include: Aspergillus, Cryptococcus Neoformans and Histoplasma Capsulatum.

Toxic Moulds (High Risk) 

Unlike pathogenic and allergenic moulds, toxic moulds seek out to intentionally harm living things. They produce mycotoxins, poisonous chemicals that can lead to temporary irritation or even prolonged illness in humans. Exposure can result from inhalation, skin contact or ingestion of mycotoxins. 

The most common toxic moulds include: Fusarium, Aspergillus, Stachybotrys Chartarum (aka “Black Mould”) and Penicillium.

Let's Wrap This Up…

Mould in our homes is more than just a bad look. It's a real health risk that can seriously affect us, our homes, and our finances. 

Remember, catching mould early and treating it effectively right away is key. A little bit of attention and quick action can make a big difference. 

Personally, we love Auro’s 3-step anti mould solution so much that its our exclusive mould removal product. It can deal with all stages of mould infestation and is an eco-friendly & non-toxic alternative to the harsh chemicals of typical removal products (without losing its ability to remove stubborn mould).

The use of organic, natural and plant-based ingredients means that allergy and asthma sufferers and people who are chemically sensitive are much more able to tolerate Auro products.

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