When I went to the library last week, I saw this sign.
What?! The non-fiction area? How can they expect me to do research for my blog? And what is Stachybotrys?
It all apparently started a month or so ago when about ten people from the adjoining Tauranga City Council offices complained of health problems. Tests of the offices showed “abundant levels of Stachybotrys which is commonly known as black toxic mould.” (Note: mold is spelled mould in New Zealand.) The City Council office workers were relocated, the area was sealed off and the upper floor of the library was also found to be affected and closed. Men wearing hazmat suits, looking like Meth cooks in Breaking Bad, could be seen carrying computers and files from the facility.
Molds are a type of fungi. Fungi, as you may remember, are a group of organisms, distinct from bacteria, animals and plants. Fungi are characterized by being able to synthesize their own food (like plants) but unlike plants, fungi have chitin in their cell walls rather than cellulose. We live in a world teeming with fungi, and only a few of the millions of species of fungi have been formally classified. Along with the more familiar mushrooms and yeast, fungi include a great number of species that live symbiotically with plants, as well as fungi that cause diseases in both plants and animals. Fungi also have many useful qualities. For example, as you may remember, the antibiotic, penicillin, is derived from the penicillium fungi.
Fungi generally live secretive lives; they are often invisible to the naked eye or we often only see them during their reproductive stages, as with the familiar mushroom, which is the fruiting or spore-bearing body of a fungus.
Mold is the common name given to a broad range of fungi that have branching multicellular elements called hyphae.
Stachybotys is a genus of mold with around fifty different species. Two species are particularly significant, Stachybotys chartarum and Stachybotys chlorohalonata, both also known as “black mold” or “toxic black mold”.
Molds such as Stachybotys reproduce by releasing huge numbers of tiny spores. While the mold is growing, a wet slime covers the spores. It is only when the mold is in a dry state that the spores become airborne. In certain individuals, inhalation of the spores in large quantities can cause health problems such as allergic reactions similar to hay fever, breathing difficulties, eye irritation, skin rashes, sneezing, cough and sometimes more serious symptoms. Symptoms are generally related to the length of exposure and the volume of spores inhaled, with some individuals over time developing a hypersensitive reaction to mold spores. That means that even a relatively minute amount of the mold spores can trigger a dramatic physical reaction in these individuals. Conversely, some individuals may have no symptoms despite being exposed for years.
The Institute of Medicine (IOM) in 2004 found there was sufficient evidence to link indoor exposure to mold with upper respiratory tract symptoms in healthy individuals, with increased asthma symptoms in asthmatics, and with hypersensitivity pneumonitis in certain other individuals. In children, early exposure to mold was linked with the development of asthma. In 2009, the World Health Organization (WHO) confirmed these findings and issued guidance. So this is what was going on to cause the library to close its upper floor.
What causes mold to grow or what allows mold to gain a foothold in a building? Mold needs moisture to grow as anyone who has ever had a shower stall in his or her house knows.
Molds commonly grow in damp or leaky buildings that allow moisture or cold wet air in and are inadequately ventilated. Buildings at risk for mold are those with inadequate insulation or with poor vapor barriers, the plastic or foil material that prevents moisture from penetrating the structural elements of a building. Plumbing problems that result in water leaks can also result in mold developing. Condensation from cooking and the warm moist air in bathrooms can also lead to mold in the absence of adequate ventilation.
Prevention, along with assuring adequate ventilation in a building, includes promptly cleaning up any water leaks or spills.
The key to mold control is moisture control.
Mold in buildings and related health concerns are a problem throughout the world, including in New Zealand. For many years in the past, New Zealand homes in particular were built without adequate insulation and ventilation and thus were at risk.
When mold ‘infests’ a building, it commonly grows in and on drywall (gypsum board) and wood but can also be present in carpets and on virtually any building material. When significant mold is present, generally those items affected will need to be removed and replaced, although mold itself can be killed by common household bleach.
Prior to moving to New Zealand, for several years I bought run-down, foreclosed houses and remodeled them. Mold was usually present to some degree in the kitchens, bathrooms and laundry rooms. If present on drywall or wood, I replaced those items and always replaced all kitchen and bathroom cabinets, appliances, carpets and flooring. In the United States, signs of mold are looked for on real estate home inspections and generally infected areas must be remedied prior to sale. Testing to determine which specific type of mold is present is generally not necessary, is cost prohibitive or simply not available.
Even when patients complain of symptoms related to living or working in a specific building, testing to determine the specific organism can be expensive or not available. Along with this, it is not always possible to identify the specific culprit among the hundreds of different organism including bacteria and fungi that can cause allergic type symptoms for dwellers in a given building.
The solution, however, remains the same. If a significant problem is present, the people are removed from the environment, the property is cleaned and remediated. This includes addressing the problem that allowed mold to develop to begin with.
Again, it is the inhalation of the spores which most often cause symptoms although some people may develop allergic reactions from touching molds. Allergic-type symptoms in individuals are treated with antihistamines and similar medications. Asthma symptoms are treated in the usual manner.
So for now the top floor of the library will remain closed while remediation occurs.
“Can I just go up there and grab a book on molds and come right back down?” I asked a librarian.
“No,” she answered.
“Even if I move quickly and hold my breath?”