Can Mould Cause Depression?

Can Mould Cause Depression?

I want to talk to you about what most people think about when they see visible mould inside their properties. Usually, they're worried about the health and safety of anyone who is using this bedroom, and they're usually focusing on things like the asset value of their property, or the potential health risks that come about through exposure to mould and water damage. That, of course include all the well-known respiratory issues, and of course, visible mould doesn't look very aesthetically pleasing, so there is in a sense a loss of amenity, and if your property has been infiltrated with unexpected water after a storm, or a flood, or a plumbing breakdown, obviously the first set of issues that you're dealing with is the cleanup, and then the impact on the livability or the habitability of your property.

Today, I want to focus on really the other issues, the fears, the anxiety issues, the impact on your mood, and I want to do this by highlighting what some of the major sections of the literature have to say about mould and water damage and its impact on mental health.

When I was deciding a couple of days ago what today's live stream would actually be about, I received this email from one of my former clients. I've redacted some of the sections, but I'm popping it up here, because I want to focus on his final sentence. He was my client a couple of years ago. He purchased a property, and the managing agent or the selling real estate agent did not disclose the severe levels of water damage that have been impacting on this property.

If I zoom in on the text inside that red box, it is going to encapsulate what today's show is all about. Now, as I told you, he's writing from his perspective about he and his wife. Let's just call her Sally. He writes, "Unfortunately, Sally became unwell last year with severe depression, and she was diagnosed with breast cancer in June this year, 2019. We would love to move or sell, but financially, we are unable to."

This is a really poignant email, and not an unusual ‘tale of woe’ about people's really very personal experiences of dealing with mould. I don't say this lightly about a ‘tale of woe’ because when you move past the financial implications of mould and water damage, you're really talking about the emotional response to an environmental impact on your life, and how this affects your well-being, how you feel about yourself, how you relate with other people. All of this needs to be taken into consideration, and so today's topic is, "Is there a link between mould and mental health?" The well-known Scream portrait picture really encapsulates this sense of fear, anxiety and mental health impacts that are very, very personal to the individual, and of course, impact on other people as well. I want to just introduce a couple of key facts, and depression is a leading cause of adverse ill health and disability worldwide, and this is according to the World Health Organization.


What they say is that there are over 300 million people who are living with depression, and that there is an urgent need for investment and support of the entire mental health sector and the disorders that go along with this because there are many of them. It is known again from WHO modeling that for every $1 spent on depression, there is a $4 plus return in terms of better health, and productivity, and ability to work within the community and society as a whole. I really want to focus today on, "What is the role of the built environment?" That is, the buildings and offices that we spend up to 90% of our time in every day. To continue on with this relationship between mould and mental health, I want to talk about the key statistic that up to 50% of illnesses are caused by indoor air pollution.

Again, these are statistics presented by the World Health Organization in their current statistics, and it's estimated that in Australia, one in three Australian homes are water and mould damaged. In the U.S.A., the figures are one in two, and in the United Kingdom, it is one in two have a dampness problem, and at least 20% of them have a mould problem. Those UK statistics were derived from the London greater metropolitan area and then extrapolating out to the rest of the United Kingdom. I've seen similar statistics for Scotland as well, and France, which is embodied in some of the publications that are in the reference list at the bottom of this show description. Now, water damage is really just one of the impacts that adds to mental health, so water and mould is one component, but also living in an aged building.

The state of repair or disrepair also impacts on how you feel about the building, whether or not you are adequately connected to utilities, such as plumbing. The number of inhabitants in a particular home and their access to things like showers and bathing facilities, all of this impacts on health and well-being. Really, the neighborhood that people find themselves in are all other factors as well, so mental health is not just impacted on by mould and water damage, but there are a whole host of other building factors, but the aim that I'm focusing on today is the relationship between mould and mental health. In order to do this, I want to move away from the biology, and I want to see how the research links the biology to you, and so I'm looking at six groups of research trends. The first, a publication that deals with families in their homes, having a known history and visible signs of mould inside their property, including mould odour, because this is a typical scenario that I find myself in weekly when people call us and say, "We think we've got a mould problem. I'm very concerned for the health and well-being of my family?" - and so the first piece of research I'll be reviewing is for those individuals.

The next research area is: "What about the humanitarian disaster relief workers?" That is those individuals that voluntarily help with the cleanup of problems after a severe water ingress. This certainly happened in Brisbane, and in Townsville earlier this year, and so the research that focuses on those emergency response workers, there's some very interesting data regarding mood, mental health, and depression. The next group is, "What about the elderly and our aging population? What are some of the research about their psychological well-being?"

The next group is going to be focusing on children and preadolescence, because obviously, in family home environments, the impact of mould and water damage always tends to focus on the potential for infections and for respiratory problems, but what about these more mood psychology problems? Now, the next group is, I want to focus and take a dive into some cell biology to look at how the role of inflammation and how that impacts on our mental health, and what the research says about that. Then, I'm going to finish today's presentation talking about the mental health impacts in a tenancy situation and what the literature says about this. The first paper came out in 2017, and its title is up on screen with the link to the paper down the bottom, but also in the show notes. This first piece of research looked at 40 families, making up [a total of] over 65 different people.

They had known mould, visible mould on their walls and floors, and that's how the researchers recruited these individuals, and importantly, when air samples were taken inside their homes, levels of fungi cultured out at much higher than the outdoor reference controls. What did the researchers discover for this group of individuals? Well, what they did is that they applied multiple physical and psychological testing, and the results were indoor mould exposures were associated with neurobehavioral and pulmonary impairments that likely resulted from the presence of mycotoxins, such as the trichothecenes. A couple of weeks ago, we talked about mycotoxins and the range of scenarios that amplify and disturb mould-contaminated building materials and aerosolize these cell wall, and spores, and fragments, and the micron and submicron fragments that become dispersed within a home, and this is where the mycotoxins occur. This particular 2017 paper is talking about the problems with psychology, and it is the mycotoxins which are considered to be the culprit. Importantly though, let's drill down into some of the data.

If we look at this table from their 2017 paper, they discovered that the ... You're going to feel really bad in that your mood is going to be worse the higher your mould state is. They use a five-factor scale to work out what mood is, and that includes measures of tension, depression, anger, fatigue and confusion. If you follow my line of reasoning as I discuss this table, you'll see that there are two groups of columns here.

One is the exposed group. That is those individuals within the study population where there was visible mould evidence and there was measured levels of mould, much higher indoors relative to outdoors. That is our exposed group. Now, then, we look at the unexposed group. These are your reference control population, and these are the people that don't have any visible mould, and their mould levels are normal, and so what they discovered is that overall, the exposed group had a mood scale of 64, relative to the non-mould exposed group of 21.

Then, if we look at individual parameters, such as tension, then tension is again well-defined within the study parameters, and you can look at this yourself for the definitions of how this was implemented in a survey format, but tension for mould-contaminated was rated at 17, whereas those individuals from non-mould contaminated areas showed 9.1. What about depression, which is one of the most well-known terms about mood and emotional well-being? Well, depression came in at nearly 16, at 15.7, whereas the unexposed group was really half that, at 8.1. Similarly, anger came in at 14 for the mould-contaminated, whereas 8.3 for the non-mould contaminated environments, and fatigue came in at 16.2, relative to 7.6 in the non-mould exposed. The last component of the mood index was confusion, and confusion came in at 13.6, living in this bedroom or a building with mould levels that are considered abnormal, relative to outdoors.

Whereas, the non-mould contaminated environment had a confusion index again of just less than half at 6.1, and so you can see that the higher the mood state, the worse you're going to feel. These are very, very important papers because they focus not on asset value, building defects, the legal implications of mould and water damage, but they focus on the psychological impacts and the impairment that goes along with dealing with these real-world problems. Now, if we move on to the next group of people, what about those individuals, as I said, who have a humanitarian profession and do disaster-related recovery work? A paper came out in 2014, which surveyed people who had taken part in the recovery effort after hurricane Katrina and Rita, and this was ... The study population was the U.S. Coast Guard. Again, they took post-disaster histories and symptom histories, and they looked at what they discovered, and they found that there was a significant positive association between mould exposure and sinus infection at a ratio of 10 to one.

Now again, this is a very alarming statistic in itself in those individuals that are charged with helping other people who are suffering are very likely to end up with a sinus infection at a 10 to one ratio versus the normal population. That means that they suddenly have an illness group of symptoms. It is these illnesses, which in a sense predispose or create a cascade effect, leading to alterations in mood. We're going to be talking about some of the underlying chemistry of this or biochemistry, or more significantly, the cell biology a little bit later, but at this point, I want to just focus back on the recovery workers. They showed that the closer they lived to the disaster zone, the more significant their depression index would be. Again, all of this is common sense, but by the same token, it's important research because the correlation with depression also was connected with difficulty concentrating.

We've talked about the connection between mould exposure and mycotoxin exposure, and impairment of the visual system with the visual contrast sensitivity tests. We did a live stream on that a couple of months ago, and that is something that you might want to follow up on as well because it's a simple method to quantify to some extent what your visual disturbance may be if you think you've been exposed to a mould or water-damaged building and are suffering problems.


The results from their studies really showed that emergency personnel are definitely at risk of post-traumatic stress disorder and depression after natural disasters, and so this paper basically added to other papers, which have reached the same conclusion. Post-traumatic stress disorder is also linked to the process of actually carrying out disaster relief in mould-affected areas, and it's not just people who are charged with disaster recovery work. What about you who have to deal with possibly weeks to months, to potentially years before your home is adequately cleaned up after water damage and mould, especially if there is a debacle involving different stakeholders who are starting or stopping work, or work is, fails to pass.

For example, we've talked about these types of issues that are prevalent in Post-Remediation Verification failures, and so certainly, many of my clients report that they have gone to their medical practitioner or healthcare provider, and actually are suffering from a type of post-traumatic stress disorder, so this shouldn't be underestimated, and these types of literatures support these claims. The conclusions were that providing adequate access to medical and psychological counselling, as well as providing appropriate PPE or personal protective equipment certainly assists with a reduction in stress and mood disorders, seen in these disaster recovery workers. Now, let's move on to another paper that came out in 2015, and this now is looking at our aged care or our aging population. In this particular study, nearly 7,000 older individuals who were living in Brazil were surveyed. The researchers were looking at the relationship between the built environment and the health of these elderly persons, and the key results showed that depression was significantly and positively associated with the number of adverse conditions in a home.

These adverse conditions in a home could be access to electricity, adequate plumbing and plumbing fixtures, overcrowding, access to other individuals that promote positive social interactions. Even the floor level has an impact on well-being, and it is known that those people who live higher up in a block of apartments experience lower satisfaction and increased experiences of psychological stress like depression. What else did this paper state? It stated that the higher the number, or the more adverse building characteristics, this increases the odds of not only having chronic health problems like high blood pressure or arthritis, but acute health problems like infections, or pneumonia, or ongoing coughs and bronchitis, and this is very significantly linked with indicators of emotional distress like depression. All the summary of this paper is saying is that the worse the property, the more adverse health conditions the elderly may experience, and the greater their emotional distress, including depression, will be when it's quantitatively evaluated or measured. Now, let's now move from the elderly back to children and preadolescence.

Again, many of my clients call me up, and they're particularly concerned about the impact of the mould and water damage on their children's health, and health followed by decrease in asset value are the first two criteria that I hear most frequently, but what about how it makes people feel, and so this study underpins this third or next question about, "How is the mould going to affect the psychological well-being of mine or your children?" The research looked at the fact that the percentage of mental health disorders in the general population in children and preadolescence is already at 10 to 20%, and that these statistics are consistent across countries and across different socioeconomic strata, but other factors that also impact on poor mental health.

We can't always blame the moulds because the mould and water damage isn't totally responsible for adverse emotional well-being, but it is certainly a significant factor.

Other things that you should be aware of is the composition of the family unit, the socioeconomic status, the employment status, risk factors, such as drug and alcohol abuse, the presence of illnesses within the family, and a whole bunch of other factors, which are again a commonsensical, but all impact on the emotional well-being of children. What is the research saying about mould and dampness?

Well, this particular paper categorically showed that the presence of mould and dampness stimulates the immune system, and this causes blood levels of inflammatory mediators to rise, and that these are strongly associated with mood disorders, and so the statement of the problem that they looked at is inflammation actually contributes to the development of depressive symptoms. If I pull out one of the graphs from this publication, you can see that when visible mould is assessed at either normal, that is you can't see it or borderline or abnormal levels of mould in the property, and again, you can go to the original paper to see the definitions of these classifications for mould, but you can see that as visible mould increases from normal to abnormal levels, the emotional symptoms for mould and dampness are correlated with increasing emotional symptoms, which are disadvantageous to the individual. If we now try and link some of these reported outcomes with what's going on inside the body within the cells, the cell biology, we can look at another old paper from 2003. Again, there's been a tranche of other papers on the impact of natural killer cells, but that's what I'm going to be focusing on now, because moulds produce a broad spectrum of secondary metabolites, and we all know that moulds produce antibiotics, such as the famous penicillin, but moulds also produce mycotoxins. It's these mycotoxins which have a very strong impact on these things called natural killer cells.

In fact, patients with a history of mould exposure show abnormal levels of natural killer cell activity. This is very, very important because NKC cells are actually linked with cancer, and we need them to protect us from cancer and that sort of thing, leading me back to this original email from the start of this presentation. We move from depression oftentimes to much more serious organic pathologies, and the literature supports this chain of reasoning, and so I should say that NKC cells are needed for innate immunity, and the results of these researchers' study was that exposure to the mycotoxins leads to psychological stress, which influences NKC activity, which then plays a role in protecting us against not just microbial infections, but also cancer. That's the key takeaway from this particular publication. Symptoms to watch for that clinicians should be aware of and are stated in this publication, individuals that are experiencing headaches, debilitating pains, nosebleeds, ongoing fevers, coughs, memory loss, depression, mood swings, sleep disturbance, anxiety, vertigo or dizziness, and chronic fatigue are all target symptoms, which are possibly linked to a dysfunction or dysregulation of your NKC or natural killer cells. This is a huge problem.

Now, let's now talk about tenancy, because not a day goes by without me receiving a telephone call from either a property manager wanting to know whether we can go out and inspect the property, because there's been an allegation of mould and water damage, or a frightened, angry or weary tenant or group of tenants saying, "Can we come out and inspect, or help, or advocate?", because they're not getting anywhere with having the disrepair or water ingress and mould problems dealt with at their property. What does the research literature say? Again, I have gone back to some of the much earlier literature because it's really good. I've chosen this paper from, that looked at a particular subgroup of people from 1990, and we're talking about 30 years ago now. This particular borough in East London had 147,000 people, and they are particularly poor from a socioeconomic perspective, and the researchers decided to look at 60 different households, and they looked at 30 having central heating, and 30 without adequate central heating.

They gave them a survey, but importantly, they used spore traps to measure the mould levels 30 years ago, as well as visual inspection and assessment of the percentage of visible mould cover inside these tenanted or leased properties, and they quickly discovered when they analyzed the data, that 82% of the tenanted properties were damp, 75% of them were mouldy, and 70% of them were cold. Other key metrics were that heating was too expensive for 30% of the tenants, and 75% of the occupants were dissatisfied with the condition of their housing. Now, tenants are all too often blamed for the dampness, and well-known human factors associated with increases in dampness really are condensation related, and this has to do with the number of occupants in the property. The fact that more occupants have more showers or baths, and cook more, meaning that there is a build-up of water vapor inside the property. Oftentimes, vents are blocked.

More people means more washing, clothes are dried indoors, giving off more water vapor. These are the stock standard explanations I hear all the time oftentimes from real estate property managers saying, "There's an allegation of mould. We think it's condensation. I think it's the tenants, but can you go and inspect it anyway?" Well, what did the research show?

The research showed 30 years ago that that's not true at all. Those excuses are simply that excuses. Yes, they are appropriate in some circumstances, but they don't explain all of the problems that occur in dwellings that have mould problems, and the research showed that the reason for the mould comes down to a failure to provide proper or adequate heating systems. I've created this table from this research because tenancy is a fundamentally important sector of the population, living in leased accommodation with less control over the building itself than if it was self-owned. From this 30-year old research, let's look at some of these statistics.

They call this back then hidden asthma because many of the people who participated back then were smokers, and they wanted to capture that potential, so they used the word hidden asthma rather than acute asthma to take into consideration those situations where people have an asthma type respiratory impact, which in a sense happens sporadically or is spiked by a certain environmental trigger, and so they find that comparing those tenants in damp accommodation with those tenants in dry accommodation, the ratio between asthma to dry is 63 to 18. What about the depression index? Well, that is 32 units in the, 32% of the population in damp housing versus half of that experiencing depression in dry housing. That is a doubling of depression simply due to damp housing. Now, what about when this housing shows signs of visible mould?

Let's skip straight to the depression, and it's pretty bleak. There is a five-fold increase in the experience of depression when the property shows visible mould versus dry conditions. This is quite overwhelming and compelling evidence that damp and visibly mould-contaminated leased properties have a huge impact on respiratory health and psychological well-being indexed with depression. Now, this has been a pretty intense livestream. To lighten it, what about those situations where you're concerned about the individuals that are tasked with helping you fix your property?

That might actually exacerbate or make your stress levels even worse, especially when some people may be charged with doing the task of mould remediation, and you're concerned that adequate care is not being taken, or there may be a dispute that you might have with your builder regarding how best to rectify the situation. Well, common sense needs to prevail, and you may need indoor air quality experts and/or building experts, and/or solicitors to solve your problems, but at the end of the day, poor quality workmanship is unacceptable and has a huge impact on health and psychological well-being. Where do we go from here? Well, property managers are essentially the fundamental link between the landlord and the tenant. Therefore, if I do a simple Google search for tenancy and mental health, the top tier responses on Google are all going to link mental health with homelessness, vulnerability, and really looking through the lens of victimhood. All of this research that I've discussed today needs to move the discussion away from victimhood or subgroups of people who are complaining about their property and focus on the very strong research-proven and supported links between exposure to water damage, adverse health, and severe impacts on mental health.

We need to discuss the building specific factors because they can't be treated as afterthoughts, because these are fundamental to the amenity conditions, and it is my position that residential tenancy advocacy needs to be expanded and there needs to be changes to legislation and guidelines that cover these issues such as fuel and energy poverty. The fact that much of our rental housing stock has inadequate heating throughout, the fact that a lot of the windows or window fenestration are too thin or inadequate, leading to well-known and very foreseeable problems for any tenants moving into properties. Agents need to be proactive and they need to drive the dialogue between themselves and the landlord in order to put a spotlight on the mental health impacts and risks to respiratory health and emotional well-being from a lot of the properties that they're leasing. In that way, it'll be a win-win for the tenant, a win-win for the agent, and at the end of the day, the landlord will end up with a property having fewer building defects that can be enjoyed for hopefully many years to come. In conclusion, I want to again highlight the fact that if you or someone you know are suffering from emotional distress caused by mould or water damage, ask them, "Are you okay?"

Contact a service provider in Australia or wherever you're watching this from who are able to provide some external support. Agencies like Beyond Blue are certainly appropriate, and don't take living with mould just as an impact on your asset value or a potential asthma trigger. It's far more insidious, and that's the take-home message. Mould can severely impact on your mood and mental well-being. I'm going to end there. Have a great day, and see you next week.

Dr. Cameron Jones





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