According to a new study, the mold that grows on walls releases toxins into the air, and these chemicals can be bad for the health of people and pets, especially if they are already allergic to particular types of fungi. The effects of wallpaper fungi are one of the causes of the sick building syndrome.
It wasn’t really evident how the mold growing on the buildings could sicken people. However, French researchers said that they tested three common types of fungi that are usually found somewhere in buildings. The team stated that the fungi are harmful because they release mycotoxins that just disappear into the air.
“These toxins can subsequently be aerosolized, at least partly, from moldy materials,” the scientists wrote in the journal Applied and Environmental Microbiology, published by the American Society for Microbiology.
What to know about the sick building syndrome
The sick building syndrome (SBS) helps explain the situation where the people that live or occupy a building start to show acute health effects that are directly related to the time they spend in that space. It doesn’t produce a specific illness, nor the specific causes of it have been identified yet. However, this feeling of sickness tends to decrease the productivity of the building occupants. The complaints may come from one particular area of the building, but it can spread to the entire structure. Most of the complaints reported by the people affected are somewhat relieved once they leave the contaminated area of the building, although the effects of neurotoxins can remain in the organism.
The sick building syndrome causes a lot of symptoms, for example, headaches, sensitivity to odors, nausea, irritation of the eyes, nose, and throat, and dizziness. It can also produce dry coughs, chest pain, shortness of breath, flu-like symptoms. Its symptoms can get to be very severe since it can also lead to cancers, asthma, pregnancy issues and miscarriages and personality changes.
20 to 40 percent of buildings have visible fungal growth
This syndrome is a concerning issue for current building occupants. According to Jean-Denis Bailly of the University of Toulouse in France and its colleagues, 20 to 40 percent of the buildings in Northern Europe and North America show fungal growth that is entirely visible to the human eye.
These scientists tested three species that are very likely to grow in buildings. These were Penicillium brevicompactum, Aspergillus Versicolor, and Stachybotrys chartarum, all of which were set to grow on a wallpaper in the lab, all of them producing mycotoxins. However, these various indoor contaminants release different mycotoxins and their mycelia – which is the part of the fungi that tries to find sources for nutrition from the environment – also differs depending on the fungi; therefore, the amount of mycotoxins that they release into the air varies too.
They wanted to know if any interference was needed for the fungi on the wallpapers to contaminate the air. They found that the transfer of toxins into the air requires air velocities that are always present in real life conditions in every building. They came to this conclusion after they simulated airflow into a moldy piece of wallpaper, including the three species they analyzed. During this experiment, they controlled and used different speeds and directions of the air.
“We demonstrated that mycotoxins could be transferred from a moldy material to air, under conditions that may be encountered in buildings,” Bailly said in a statement. “For instance, Aspergillus Versicolor, a potent producer of sterigmatocystin (STG), is one of the most frequent fungal contaminants of indoor environments that can be found together in building materials, in dust or in the air samples.”
The toxins that these fungi release are so small – smaller than spores – that people can easily inhale them and they can penetrate into the respiratory tract.
Levels of toxins released by wallpaper fungi must be a parameter of indoor air quality
The presence of mycotoxins is commonly associated with contaminated food. However, it is important to raise awareness about the incidence of mycotoxins in small particles such as dust and on wallpapers, and how they can readily affect people just by breathing.
“It seems important to take these data in consideration for risk assessment related to fungal contamination of the indoor environment and the possible toxicity associated with inhalation of these toxins” is stated on the report of the research.
Even if there are many benefits to living in an energy-efficient house, Bailly and his colleagues also highlighted the fact that these fungus-associated threats are quite bigger in these type of houses because they are isolated from the outside to save energy. Isolated water-using appliances – for example, coffee makers – provide the perfect conditions for fungi to grow.
Source: NBC NEWS