Rising threat: Perm scientists reveal how black mold affects quality of life.

Mold is a household rather than a scientific term. The collective term "mold" refers to colonies of fungi that are found everywhere. Their structure consists of mycelium, which is made up of thin, colorless (sometimes slightly pigmented) threads, webs that grow indefinitely and branch out sideways – these are called hyphae. Some of them grow vertically and form bulbous ends where spores mature. When they are ready, the sporangium bursts and releases them into the air.

— Like any other species, black mold (Aspergillus niger) spreads through spores. The characteristics of this species are unique: rapid reproduction and growth on a variety of surfaces, the ability to tolerate highly acidic environments, and the production of toxic substances, says Anastasia Zorina, associate professor of the Department of Chemistry and Biotechnology at Perm Polytechnic University, PhD in biological sciences.

Today, this type of mold is used to produce citric and gluconic acids, some natural food pigments, and enzymes. For example, glucoamylase and amylase from these fungi are used to create malt syrup in confectionery production. Xylanase from black mold breaks down mucilaginous substances during bread baking, improving the porosity and uniformity of the bake. Additionally, this type of mold is used in the production of detergents to soften cellulose fibers.

Dangerous species and where they live?

According to the expert, there are about 100,000 species of this microorganism. Their color can be not only black, as one might assume. Among the most common are the following.

— For example, colonies of the Aspergillus fungus (over 185 species) often live in humidifiers, washing machines, and air conditioners. This type of mold covers damp ceilings, joints between tiles in bathrooms or kitchens. They produce toxins and can cause dozens of respiratory diseases, says Anastasia Zorina.

Cladosporium (over 30 species) mainly grows in areas with ventilation issues, as well as on food and damp clothing. The key distinguishing feature of this species is its velvety texture, with shades ranging from greenish-turquoise to deep black.

Alternaria (over 20 species) is also known as "black rot"; it most often affects plant-based foods and can lead to allergic rhinitis and atopic dermatitis.

Stachybotrys – the infamous black mold found on wallpaper, paper, or books, whose danger increases as the fungus grows. Daily inhalation of its spores can result in headaches, chest tightness, and sudden coughing fits.

Mold prefers comfort

Humanity creates a comfortable environment for living. These conditions are also favorable for mold. A constantly maintained temperature of 18-25 degrees Celsius in apartments or houses is optimal for the growth of microorganisms. Whitewashing, wallpaper, paper, fabrics, carpets, leather, wooden finishes, and drywall – all these are suitable substrates for mold growth, while airtight plastic windows create the necessary humidity.

— Microspores can easily enter an apartment, and thereafter, it all depends on whether the climate is favorable for reproduction. Once in the right conditions, the spore germinates, forming mycelium. Other shorter threads penetrate deeper into the surface. Any place in an apartment with constant moisture and stagnant air is potentially suitable for reproduction, says Anastasia Zorina, associate professor of the Department of Chemistry and Biotechnology at Perm Polytechnic University, PhD in biological sciences.

Folk methods are not omnipotent

To create an environment unsuitable for mold reproduction, it is necessary to use antiseptic primers during renovations, maintain moderate humidity, regularly ventilate, timely dispose of spoiled items and food, and conduct regular checks of the sanitary condition of ventilation, drainage systems, floors, and ceilings.

There are many different ways to remove black mold, including folk methods that are widely spread on the internet.

— Folk recipes are only applicable in cases where mold damage is minimal. In other cases, it is better to use specialized products. These are already prepared and sold in stores. Before using any of them, it is important to thoroughly read the instructions and ensure they are suitable for the selected type of surface. One should not neglect personal protective equipment – rubber gloves, masks, respirators, advises Anastasia Zorina.

If you cannot manage to deal with the fungi on your own, contacting a specialized disinfection company that will not only clean the premises but also provide recommendations to prevent recontamination is a wise decision.

Little spots on food are just the tip of the iceberg

— Typically, the mold we see on food is just the surface. The actual fungus has already spread deep inside, especially in the case of loose foods like jam. Therefore, most moldy products should be discarded. Only those with a dense and dry structure, which the fungal threads cannot penetrate quickly, such as hard cheeses, can be saved, warns Anastasia Zorina, associate professor of the Department of Chemistry and Biotechnology at Perm Polytechnic University, PhD in biological sciences.

If it is possible to carefully cut the mold away with a knife, you should cut at least 2.5 centimeters around the contaminated area. Avoid touching the mold with the knife, and wrap the cheese in a new bag or film. Hard vegetables, including carrots, beets, and cabbage, should be thoroughly cleaned, cutting away the affected areas. However, if mold appears in a jar of jam, sour cream, or another liquid product, it's better not to take risks and dispose of that food. There is no guarantee that deeper layers are not contaminated with mold.

According to the expert, if one consumes a product contaminated with mold once, nothing serious will happen, especially if the immune system is not weakened. In the acidic environment of the stomach, microorganisms will be neutralized. However, if moldy foods are consumed frequently or if the immune system is compromised, there is a risk of poisoning or allergic reactions.

Inhaling mold spores

— Black mold releases mycotoxins into the surrounding air. When inhaled into the lungs, they can cause a sudden deterioration in well-being: cough, allergy, runny nose, swelling of the upper respiratory tract, and poisoning. They are particularly dangerous for individuals with asthma and allergies, as exposure to fungi can provoke more severe conditions, says Anastasia Zorina.

The main danger to humans is mucormycosis. This disease develops when spores from the genera Rhizopus and Mucor are inhaled or enter through damaged skin, and less frequently, when swallowed. They are widely found in the environment, especially in soil and decaying organic materials. Once inside the body, their spores germinate into threads that can penetrate blood vessels. This leads to thrombosis and ischemia of tissues, resulting in necrosis and black scabs.

— Typically, such an infection develops in individuals with low immunity. Mucormycosis has several clinical forms and can affect the lungs, skin, nasal sinuses, eye sockets, and the mucous membrane of the gastrointestinal tract. Consequently, symptoms will vary depending on the clinical form, making it very important to consult a doctor for treatment as soon as possible, says Anastasia Zorina, associate professor of the Department of Chemistry and Biotechnology at Perm Polytechnic University, PhD in biological sciences.