Indoor mold growth is a common problem and is most likely to occur during the fall and winter months.
Walls, clothes, books, toys and even CDs - nothing is sacred when it comes to mold growth. Its seemingly insidious growth can turn prized possessions into musty, moist sadness that only look fit for the garbage.
But for all its corrupting menace, to what extent should we be worried about mold when it invades our homes? If these are the effects that it can have on our possessions, what effects can it have on our bodies?
In this spotlight feature, we take a look at precisely what mold is, what causes it to grow, whether it is bad for our health and, if so, what can be done to stop it.
What is mold?
Molds are a form of fungus. There are many different molds and they can be found both indoors and outdoors. Molds spread through the production of spores, which are present in all indoor environments and cannot be removed from them - spores are capable of surviving in harsh conditions that otherwise prevent the normal mold growth.
Molds grow best in moist, warm and humid environments - easily created in the home during the winter. When mold spores land on a damp spot they can begin to grow, digesting the material they are growing on as they do so. Molds are capable of growing on a variety of different surfaces, including fabric, paper and wood.
Common indoor molds include:
- Alternaria - found in damp places indoors, such as showers or under leaky sinks
- Aspergillus - often found indoors growing on dust, powdery food items and building materials, such as drywall
- Cladosporium - capable of growing in cool areas as well as warm ones. It is typically found on fabrics and wood surfaces
- Penicillium - typically found on materials that have been damaged by water and often has a blue or green appearance.
Molds take a variety of forms and textures, appearing as white, black, yellow, blue or green and often looking like a discoloration or stain to a surface. They can also have a velvety, fuzzy or rough appearance, depending on the type of mold and where it is growing.
How does mold get into our houses?
Large patches of damp, such as those caused by leaks, provide an ideal environment for mold growth.
Mold spores, invisible to the naked eye, can be found everywhere, both indoors and outdoors. Spores make their way into the home either through the air or after attaching to objects or people. Open windows, doorways and ventilation systems are all gateways through which spores can enter. Clothing, shoes and pets can all facilitate the arrival of mold within the home.
Mold will only grow if spores land somewhere that has the ideal conditions for growing - places with excessive moisture and a supply of suitable nutrients. If this does not happen, molds do not normally cause any problem at all.
Mold can often be found in areas where leakages and flooding have occurred and near windows where condensation builds up. Wet cellulose materials are most supportive of mold growth, including paper products, cardboard, ceiling tiles and wood products. Wallpaper, insulation materials and upholstery are other typical launchpads for mold growth.
Mold growth is usually noticeable - it is usually visible and often produces a musty odor.
The World Health Organization (WHO) report that 10-50% of indoor environments in Europe, North America, Australia, India and Japan are estimated to be affected by indoor dampness. This figure suggests that mold could be a highly prevalent issue in locations spread across the world.
In North America, the US Environmental Protection Agency (EPA) state that "if mold is a problem in your home, you should clean up the mold promptly and fix the water problem." But do the EPA recommend dealing with mold swiftly because of the damage it can do to property? Or because of the damage it could do to health?
Potential effects of mold on health
"Mold exposure does not always present a health problem indoors," state the Centers for Disease Control and Prevention (CDC). "However some people are sensitive to molds."
Meanwhile, the WHO say that a moldy environment is associated with and could worsen indoor air pollution - a risk factor for certain respiratory conditions:
"Excess moisture on almost all indoor materials leads to growth of microbes, such as mold, fungi and bacteria, which subsequently emit spores, cells, fragments and volatile organic compounds into indoor air. Moreover, dampness initiates chemical or biological degradation of materials, which also pollutes indoor air."
Molds can produce a number of substances that can be harmful. Allergens, irritants and mycotoxins - potentially toxic substances - can affect individuals who are particularly sensitive to them.
In particular, the EPA state that exposure to molds can irritate the eyes, lungs, nose, skin and throats of individuals, even if they do not have a mold allergy.
Mold allergies produce similar symptoms to other allergies to airborne substances affecting the upper respiratory tract, such as pollinosis. These include:
- Blocked/runny nose
- Itchy nose
- Itchy throat
- Watery eyes.
In addition, people with a mold allergy that also have asthma are at an increased risk of having their asthma symptoms triggered by a moldy environment, according to the CDC.
However, Prof. Stephen Spiro, the deputy chairman of the British Lung Foundation in the UK, informed MNT that the presence of indoor mold can go further than simply exacerbating pre-existing conditions:
"Certain mold species can cause serious lung infections and scarring. For instance, in some asthmatics, inhaling the spores of a species of mold called aspergillus can lead to a condition called allergic bronchopulmonary aspergillosis, which can impact on the breathing."
Individuals whose immune and respiratory systems are already weakened by chronic conditions would appear to be more susceptible to adverse effects from indoor mold. Prof. Spiro also told MNT that among patients with certain blood disorders, inhaling mold could even lead to fatal complications.
Although more conclusive evidence is required, the CDC report that some research suggests there could be an association between indoor exposure to mold and the development of respiratory conditions in otherwise healthy people.
In 2004, the Institute of Medicine (IOM) reported that there was enough evidence to connect indoor mold with the development of upper respiratory tract problems in healthy people, and some evidence suggesting the same in healthy children.
More recently, the CDC state that exposure to mold early in a child's life could be associated with the development of asthma. However, this theory is opposed by the hygiene hypothesis.
The WHO's guidelines for indoor air quality explain the hygiene hypothesis - the theory that growing up in a hygienic environment can increase the risk of a person developing allergies. Several studies have found evidence supporting the hygiene hypothesis, but evidence so far has been mixed.
As a result, the WHO conclude that there is "sufficient evidence of an association between indoor dampness-related factors and a wide range of respiratory health effects," including asthma, respiratory infections, coughing, wheezing and dyspnea.
While heavy exposure to indoor mold could plausibly play a causal role in the development of these health conditions, the WHO state that such an association has yet to be established conclusively.
Protection and prevention
Condensation on windows often leads to mold growth. Reducing humidity levels indoors or increasing ventilation can prevent it from occurring.
Despite the inconclusive nature of current research, the CDC and EPA recommend that any mold growth should be dealt with promptly.
Both organizations state that controlling moisture is most crucial to preventing mold from growing indoors. Acting quickly in the event of a leak or spillage is important, and drying areas within 48 hours of exposure to excess moisture should ensure that mold will not grow.
The level of humidity within the home is another important factor. Although it may not be immediately apparent, a high level of moisture in the air will promote mold growth. Condensation on windows is often a sign that humidity is high within a room.
Increasing ventilation by opening windows or using an extractor fan reduces the level of moisture in the air. Humidity can also be reduced in specific rooms by avoiding moisture-producing activities in them, such as drying clothes or using kerosene heaters.
When cleaning mold from hard surfaces, commercial products, soap and water or a heavily-diluted bleach solution can be used. Always dry surfaces that have been cleaned thoroughly to prevent mold from growing back.
Be wary of porous materials that have been affected by molds, such as fabric or wood. Mold can infiltrate these materials, may be impossible to remove completely and could potentially grow back if the conditions are right. In many cases, it may be best to get rid of items such as these that have been affected for a long period.
Patches of mold that are larger than 3 ft by 3 ft may be best tackled by professional mold cleaning experts.
If you are worried by any potential exposure to mold or you believe that you are having associated health problems, it is recommended that you contact a health service provider.
Tidy house, tidy mind
While evidence is inconclusive overall as to the extent that mold can affect health, there appears to be enough evidence available to suggest that people should be wary of it.
Even if it is the case that mold does not cause health problems, as some studies have suggested, the presence of mold indoors is indicative of a damp environment, which is known to be hazardous to health.
The impetus for getting rid of mold from the home is also much greater if the health of affected individuals is in any way compromised by chronic lung conditions or immune system impairment.
It may just be a case of reassurance, that having a home free of mold equals having a mind free of doubt and worry. Patches of odorous toxic-looking black mold can seem intimidating, and while it is possible that these might not be harmful to everyone, there is nothing like a clean, airy and dry room to instill confidence about one's health.
In the wake of horrible family rows, short of leaving my father, my mother would do something that shook the foundations of my childhood. She would step into our living room and, spurred by rage, spite and last-ditch efforts to restore order in her life, she would single-handedly move all the furniture around. The sofa was relegated to the place held by an imposing bookcase. The bookcase would be shunted over to a corner that belonged to an unassuming cabinet, now demoted to another corner where it sat in the dark under the terrified gaze of two leather armchairs squatting in the maelstrom.
To the outside world my mother was furiously rearranging furniture. To those who knew better she was trying to take control and putting a new face to her life. Since she couldn’t change much of anything and had no intention of buying new furniture, perhaps she was just trying to give her life a new look. It was madness, but it taught me that if changing the layout of your problems doesn’t necessarily solve them, it does make living with them easier. It also taught me that what came in the wake of any change, however terrifying, couldn’t have been more thrilling.
Like my mother, memoirists, unable to erase the ugliest moments of their past or unwilling to make new ones up, can shift them around. They don’t distort the truth, they nudge it. Everyone has reasons for altering the past. We may want to embellish or gloss over the past, or we may want to repress it, or to shift it just enough so as to be able to live with it. Some, in an effort to give their lives a narrative, a shape, a logic, end up altering not the facts they’ve known, but their layout — exactly what my mother was doing. Life as a Rubik’s cube. Eventually, like someone jimmying the tumblers on a lock, she might spin things just right and find a sequence that finally made sense. She never did.
There are many things about my life that I wish had been different and that I still find difficult to live down. As a memoirist, I may claim to write the easier to remember things; but I could also just be writing to sweep them away. “Don’t bother me about my past,” I’ll say, “it’s out in paperback now.”
Writing the past is never a neutral act. Writing always asks the past to justify itself, to give its reasons… provided we can live with the reasons. What we want is a narrative, not a log; a tale, not a trial. This is why most people write memoirs using the conventions not of history, but of fiction. It’s their revenge against facts that won’t go away.
Writing alters, reshuffles, intrudes on everything. As small a thing as a shifty adverb, or an adjective with attitude, or just a trivial little comma is enough to reconfigure the past.
And maybe this is why we write. We want a second chance, we want the other version of our life, the one that thrills us, the one that happened to the people we really are, not to those we just happened to be once.
And yet, after we’ve moved the furniture around and made peace with our little nudges, the question that no one asks is: what happens to the past after the writing process is done with it, after all our epiphanies have cast their radiance? Might as well ask, what happens to Marcel Proust once he’s done writing “Swann’s Way”? Or better yet, what happens when he dips a madeleine in tea long after he’s written about the memories it triggers? Can Proust eat a madeleine after writing about it and still expect the miracle of remembrance to occur, now that writing has taken over experience? Similarly, if there is a primal layout to a living room, what happens to it once the writing process has shifted things around?
And here’s a strange fact. Within a few weeks after my mother had rearranged the furniture, it was no longer possible to recall the previous configuration of our living room. Ask us to recall a store that was there two stores earlier, and we won’t know whether we’re remembering, trying to remember or just making things up.
Writing not only plays fast and loose with the past; it hijacks the past. Which may be why we put the past to paper. We want it hijacked.
In 1990 I published an account of a walk with my brother on our last night in Alexandria. Four years later, in my memoir “Out of Egypt,” I removed my brother from the scene and, instead, described taking that same walk by myself. Today there are two competing versions of that walk floating on the Web. When I returned to Egypt in 1995, I walked along that same stretch to test whether I remembered walking there alone or with my brother. And suddenly it occurred to me that I might have made the whole thing up.
If I couldn’t tell for certain that I had, it’s because the two published versions stood in the way of what had actually happened on my last night. Today I remember the walk I took alone, but only because I spent more time writing it. Ask me which of the two is truer, I’d say, “Probably the walk with my brother.” Ask me again and I might admit making the whole thing up. Ask me yet again, and I won’t remember.
Here we enter the spectral realm of quantum mnemonics. There is no past; there are just versions of the past. Proving one version true settles absolutely nothing, because proving another is equally possible. If I were to rewrite the scene one more time, this new version would overwrite the previous ones and, in time, become just another version among many.
Words radiate something that is more luminous, more credible and more durable than real facts, because under their stewardship, it is not truth we’re after; what we want instead is something that was always there but that we weren’t seeing and are only now, with the genius of retrospection, finally seeing as it should have occurred and might as well have occurred and, better yet, is still likely to occur. In writing, the difference between the no more and the not yet is totally negligible.
We can have many pasts, just as we can have several identities at the same time, or be in two places in our mind without actually being in either. For every life we live, there are at least eight others we’ve gotten close to but may never know. Maybe there is no true life or false life, no remembered or imagined itinerary, no projected or revisited moments, no worthy or wasted days, just as there is no such thing as mask or face, truth or lie, right or wrong answers. Can something be and not be at the same time?
There is no answer. The only possible out is the one my mother taught me: that there is a pleasure, something so unspeakably thrilling, in uncovering the other version of our life, that, given a few days, a few weeks, a few years, this version will be the only one worth writing and, therefore, worth remembering.
André Aciman, who teaches comparative literature at the CUNY Graduate Center, is the author of “Harvard Square.”
Draft is a series about the art and craft of writing.