By: - Updated: August 15, 2018


With about 50 known species, Alternaria molds are extremely common and widespread. The spores are found in high concentrations during dry, windy conditions, which make them extremely airborne. As such, susceptible individuals can develop allergies upon exposure to the mold spores.

Alternaria is a plant pathogen, and some species are also parasitic on living plants. In fact, statistics show that at least 20% of lost agricultural yields are due to various Alternaria species, and sometimes, these losses can reach up to 80%.

Alternaria Species

The Alternaria fungus contains a total of 50 known species. Some of which include: Alternaria alternate, which is by far the most common of all the other species, Alternaria teunissima, Alternaria infectoria, Alternaria chartarum, Alternaria stemphyloides, Alternaria geophilia, and Alternaria dianthicola. All these species are isolated from infections. The causing agents of other Alternaria species have not yet been specified.

Interesting facts about the Alternaria Mold

The Alternaria mold, in order for it to grow, requires a temperature of 2 – 32 C, with a pH level of 4 to 5.4. The least water they need in order to grow is 0.85 and 0.80 but this also depends on the species. There are 50 species of Alteranria. They grow very fast and can reach maturity in just a period of 5 days. Just like any other molds, Alternaria thrives in humid areas.

Where does Alternaria usually grow?

Alternaria is typically found outdoors, on dead plant materials, cereals, grasses and soil. It can grow on a variety of other high-cellulose substrates and does not require significant amounts of water to grow.

Indoors, Alternaria can be found in carpets, wallpaper, textiles, window frames and air. However, Alternaria spores identified in indoor samples often originate from the outdoor environment.

What kind of mold is Alternaria?

There are two specific common species of the Alternaria mold, they are Alternaria alternata and the Alternaria tenuissima. This mold can commonly be found outdoors but can also be found in buildings like an apartment or even a house. The mold can grow from spring all through to summer. The mold can grow among other species of molds like the Stachybotrys, phoma, and Fusarium molds. Due to the fact that it is common in summer and spring, it is thought of as a common allergen.

The common habitat of the Alternaria mold include the plants, grass, tree, and soil. It is mostly found in areas with average climate. In dry seasons and when it is hot and windy, a lot of spores are spread in the air. The indoor molds are caused by spores that get transferred inside buildings.

Just like any mold species, it is definitely not strange that this mold loves the humid, damp and dark environment. They commonly grow on foods and wood, apart from the Alternaria alternate which grows on tiles, bricks, wallpapers, canvas, iron, and canvas.

What health problems are caused by Alternaria mold?

The most vulnerable people to these molds are those with pulmonary diseases, asthma, allergies or even those who have a weak immune system.

Some of the symptoms that might occur when exposed to the mold are coughing, runny noses, sore throat, sneezing, throat irritation, headache, fatigue, dizziness, red eyes. Rashes, itchy eyes, itchiness on the skin, and watery eyes,

When one is exposed to the mold for long, it can cause some health damages, especially in the elderly, children and babies.

Once you notice any of these symptoms especially during the summer and spring seasons, and you realize that maybe your house might be leaking, you need to check for the molds because there is a high chance that it is the cause.

Always seek medical advice when exposed to molds.

Is Alternaria toxic for humans?

Many species of Alternaria have been known to cause health problems in humans. They produce mycotoxins that affect the respiratory system, skin and nails. Other species are common allergens that may lead to asthma, hay fever, etc., but they rarely cause serious infections. They are of particular risk to immuno-suppressed and wounded individuals.

What are Alternaria Allergy symptoms?

This mold is a major cause of several allergies, mostly during the summer and spring seasons. This is because of its vast presence in the outdoors. Allergies in many people cause them to have red eyes, runny noses, feel dizzy and sneeze. This is the same case when someone is exposed to this mold.

Where can be Alternia mold be found in house?

No matter your location or the season you are in, molds are airborne and can easily get into your house. This is because they look for a place to multiply and houses provide that humid and warm environment to do so. The bad news is that these molds can settle on your food, clothing, furniture and even the plants or flowers in your house. The mold also grows under the carpets and inside the walls as well. They can get in your shower, attic and basement. If your house is humid you are at a higher risk of housing these unwelcomed guests.

Mold can prove very difficult to get rid of once it is in your house. You need to call a mold removal company immediately. Do not wait for the mold to grow because its presence is a huge health risk to your family.

In order to prevent molds from entering your home, keep doors and windows closed especially when it is dry, hot and windy, make sure your rain gutters are either repaired or replaced. Check if your kitchen and bathroom have leaks, keep floors dry especially around the washing machine, dishwasher and toilet areas. Reduce the level of humidity in the interior of your home using a dehumidifier. The readings should not go beyond 5o percent. Lastly, clean your basement, and bathrooms regularly with products meant to kill molds. Try not to put a carpet in your bathroom. Maintain a good heating system and remove moisture from seats, floor, and walls.

How to detect Alternaria?

You can identify Alternaria with professional air testing for mold and surface sampling; without such tests and analyses, however, it is difficult to distinguish it from some Ulocladium species (for example, Ulocladium chartarum, which is very common in indoor environments).

How to treat and remove Alternaria?

You need to get rid of the Alternaria mold from your home as fast as you can regardless of its kind. Molds may not be a health risk at first but a prolonged exposure to it is a serious health risk. Alternaria grows with time, and if not removed can spread in your whole house with time. This is a health hazard to you and your family, but the good news is that it can be prevented.

Some people would prefer to treat Alternaria on their own. It is largely recommended to call a professionals like Mold Busters to treat the mold. This is because they are experienced in busting molds and they know how to handle the whole situtation. They also have ways to test for the presence of molds.

Calling in the professionals is definitely the best way of getting rid of Alternaria from your house.