Little time? At the end of the text there is a summary.

Anyone typing in Google the words "mold" and "sick" gets spit out to the 400,000 search results. For consumers, it is often difficult to understand which pages provide legitimate information and which fears stir. Are itchy, red eyes and irritated coughs a sign of mold in the apartment? Can this actually cause rheumatism, gastrointestinal discomfort or cancer, as read in some places? And is a cheap self-test on mold from the Internet makes sense?

To reassure us: "Our resistance to mold is very high," says Thomas Schupp, toxicologist at Münster University of Applied Sciences. "As a healthy person, I do not have to panic right away, but I have to be active." Because mold is more than an aesthetic problem. He can make you sick. For some people it is also more dangerous than for others.

Everything that grows in moisture

But what is mold anyway? "A collective term for different fungi," says biologist Armin Schuster, who works at the Institute for Infection Prevention and Hospital Hygiene at the University of Freiburg. "The microorganisms grow filiform, they form spores and degrade organic substances."

Schuster is familiar with the mushrooms, he has until recently even made measurements and inspections in apartments. Although there is no longer any facility for home medicine and interior hygiene, paid telephone advice is still offered. "In a broader sense, the term also includes bacteria, yeasts and mites," he says. In short, the entire microbiome that thrives in moisture is mold.

And that surrounds us naturally. It is always present in the indoor and outdoor air and provides about the typical smell of forest soil. It is important for nature, so that old leaves or wood rots. "If it grows in an apartment, however, that is always a serious defect that needs to be eliminated," says Schuster. A problem that is widespread: In almost one in ten apartments in Germany are damage with mold.

Problems even in well-insulated new buildings

For mold to thrive, it needs moisture. "If the humidity is over 70 percent over a longer period of time, certain mold fungi can already grow, with more than 80 percent showing an infestation within a few days," says Schupp. The reasons for the increased humidity can be manifold: Poor ventilation, defects in the building structure, water damage or cold surfaces due to inadequate insulation, where the water condenses.

"Mold is not just a problem in old buildings," says Schuster. He also appears in well-insulated new buildings. "If, for example, the screed is inserted, if the extremely tight-fitting windows are already in place and no one ventilates properly, they quickly have a mold problem."

Whether wood, silicone joint, wallpaper or carpet - the mushrooms feel comfortable on many surfaces, they also find food everywhere. For the typical musty cellar odor, the metabolic products of mold are responsible, so-called MVOC (Microbial Volatile Organic Compounds), which are volatile organic compounds. The fungi also release spores or cells and cell debris.

Mold can trigger asthma and allergies

People who have their immune system shut down by chemotherapy, for example, should not take moisture and mold lightly. "Are the defenses extremely weakened, there is actually a risk to life and limb," says Schuster. Then a mold fungus infection can develop, a so-called mycosis, which is dangerous and can even be fatal.

Other diseases are more likely to be associated with moisture and mold. Thus, mold can trigger or worsen symptoms in existing asthma. "Children who grow up in wet homes also have more asthma," says Schupp. According to the guideline, a kind of treatment recommendation for diagnosis and therapy, asthma sufferers are therefore to be particularly protected, as are patients with CF, who often suffer from chronic cough and respiratory tract infections.

"In principle, mildew can also lead to asthma or allergies in healthy people," says Gerhard Wiesmüller, a specialist in hygiene and environmental medicine at the health authority in Cologne and guideline coordinator. At risk are, for example, those who already have other existing allergic diseases or predisposition to it. However, there must be contact with certain mold fungi for a long time. "Molds are not as potent allergens as grasses or pollen, sensitization is relatively rare," said Wiesmüller. "And it does not mean that allergic symptoms occur."

On the internet is often exaggerated

In general, respiratory complaints, eye, nose and throat irritation, a stuffy nose, a dry cough and tiredness can show. Because flat mold - unlike those in the environment, such as in the chaff - consists of very many and very small spores. These reach deep into the bronchi. The body mobilizes its defense, inflammatory reactions take place. "Such symptoms usually disappear again when the mold damage is eliminated," says Schuster.

Even Wiesmüller calms down: A lasting health damage is usually not to be feared. "But there is no reason not to do anything, because risking your spurs for too long risks the irritation symptoms, such as respiratory tract inflammation, becoming chronic."

There is no adequate or reliable evidence that housing mold is associated with rheumatism, the lung disease COPD or even cancer. This also applies to gastrointestinal diseases or infertility.

Daily ventilation oxygen in, pollutants out

"Often exaggerated on the Internet and the danger that emanates from mycotoxins," says Schuster. While some of these fungal toxins may indeed be carcinogenic. But: "They only get into the air in very small quantities." According to the guideline, according to the current state of knowledge, there is no danger.

"Of course, that's different with a renovator, who cuts the plaster off and suddenly inhales a lot of biomass," says the biologist. "He has to protect himself." Also MVOC, responsible for the typical smell of mold, have no acute, direct health effects. Anyone who develops an aversion, however, can still react with nausea and headache.

Red eyes and cough: Is mold the cause?

Anyone who is not sure from where complaints such as coughing and itchy eyes stir, should first consult a specialist physician, such as an environmental doctor. "Often, a house dust mite allergy is more likely," says Wiesmüller. Blood and skin tests can help in the search for clues. However, they are only available for very few molds. Moreover, they are not always reliable. Important also: It should be tested on the antibody immunoglobulin E (IgE), a protein that repels exogenous substances and plays a role in immediate-type allergies. The body reacts immediately to intruders with immune symptoms such as itchy mucous membranes, coughing or sneezing.

It does not make sense to test IgG - another protein - on a flat mold, says Schuster. Although some doctors still offer it. "It just shows that someday you had contact with mold - which applies to a large part of the population." If the complaints do not occur when you leave the apartment for a longer period of time - such as a weekend visit to friends - this is also an indication.

DPA

mold stain

If the mold is already visible, a room air measurement is unnecessary. It can only be used to determine how likely it is that a mold source exists. A limit as of when a burden is harmful to health, there is not. Schuster also advises to get well informed in advance. "With such a measurement, much can go wrong, not every biologist or engineering firm that offers them is well-versed."

The moisture has to disappear

The 2017 update of the Immune System of the Federal Environmental Agency (UBA) helps with orientation. "Cheap tests from the Internet, they can give the same," says the mold expert. "That also applies to sedimentation plates." He is also skeptical of gray-haired dogs.

Many offices also suggest that you take samples yourself and send them in. He also advises against this: "The sampling and inspection on site is the most important thing, something that must be done by someone who is experienced." However, such a measurement can quickly cost hundreds of euros. "If the health is significantly impaired, it may be worthwhile to ask the health insurance company, if it takes over costs," says Schuster.

Who wants to get rid of the mold, must ensure that the moisture disappears - for example, by a professional renovation. The UBA recommends against biocides for control. "This is not permanent protection, many of these funds also have a risk potential and burden the indoor air," says Schuster. A disinfection with alcohol also does not fight the cause. Even lime paints only help for a limited time.

For the expert is therefore clear: "To permanently have his peace, the source of the evil, so the moisture must be found." Then it means: repair weak points, remove infested material, avoid dusts - and then thoroughly clean, wash and clean. "Experts need to work on bigger problems," says Schuster.

In summary: Indoor mold is dangerous, especially for people with weakened immune systems and asthmatics. But even healthy people can irritate the respiratory tract. Doctors can clarify whether mold causes the symptoms or something else behind it. For mold to disappear permanently, the moisture that it needs to grow must be combated.


Additional information

  • Tips to prevent mold growth by improper ventilation, heating or incorrectly placed furniture, can be found here.
  • How high the humidity is, can be estimated with a hygrometer. There are already around 20 euros in the hardware store. Measure with it in different places in the apartment.
  • Molds can not penetrate through thick masonry or wallpaper, but cracks and joints are sufficient.
  • The updated guideline of the Federal Environmental Agency for the prevention, registration and remediation of mold infestation in buildings can be found here. There is listed in detail, among other things, what is to be considered in the removal of mold.
  • Important points of contact from the environmental physician over experts up to local tenant associations and mold networks the consumer center NRW listed on your side. There is also a current, fee-based guide.