Air + Surface Mold Test Kit Bundle

Identification

Stachybotrys is identified by its dark, pill-shaped spores and rough outer surface. Often called "black mold," it is one of the most well-known toxigenic mold types and can be recognized through microscopic examination at 400× magnification.

Where It Grows

Stachybotrys grows on cellulose-rich materials such as drywall, ceiling tiles, wood, cardboard, and wallpaper. It requires sustained moisture, making its presence a strong indicator of significant water damage, ongoing leaks, or flooding. Outdoors, it grows on decaying plant matter and in soil.

Health Considerations

Stachybotrys may trigger Type I allergic reactions, including respiratory irritation, coughing, sinus issues, and asthma-related symptoms in sensitive individuals. Some strains can also produce mycotoxins, specifically trichothecenes.

Identification

Aspergillus is identified by its small, round spores. Without intact fruiting structures, it can be difficult to distinguish from Penicillium. For this reason, Aspergillus and Penicillium are often reported together as a group, commonly labeled "Pen/Asp," on direct microscopy laboratory reports. Colony colors vary by species.

Where It Grows

Indoors, Aspergillus grows on wet building materials and is commonly found on dusty surfaces, such as walls, when indoor humidity is high. It can also grow on stored foods. Outdoors, Aspergillus grows in soil, compost, decaying leaves, and other plant materials.

Health Considerations

Aspergillus may trigger Type I allergic reactions, including sneezing, a runny nose, itchy eyes, and worsening asthma symptoms in certain individuals. Some species can cause lung infections, known as aspergillosis, particularly in individuals with weakened immune systems or existing lung diseases.

Certain species can also produce harmful mycotoxins. Additionally, Aspergillus can contribute to allergic lung conditions involving Type III hypersensitivity in susceptible individuals.

Identification

Penicillium is identified by its small, round spores. Without intact fruiting structures, it can be difficult to distinguish from Aspergillus. For this reason, Penicillium and Aspergillus are often reported together as a group, commonly labeled "Pen/Asp," on direct microscopy laboratory reports. Colony colors vary by species.

Where It Grows

Indoors, Penicillium grows on water-damaged materials and is commonly found on dusty surfaces, such as walls and ceilings, when humidity is high. Growth can occur even without a leak or visible condensation.

Outdoors, Penicillium grows in soil and decaying plant matter. It can also grow on various foods.

Health Considerations

Penicillium may trigger Type I allergic reactions, including sneezing, a runny nose, itchy eyes, and worsening asthma symptoms in certain individuals. Some species can also contribute to lung conditions involving Type III hypersensitivity. Certain species can produce mycotoxins.

Identification

Cladosporium is identified by its medium-sized spores, growth in chains, and characteristic attachment scar, often called a "birth scar," at one end of the spore. It is one of the most common types of airborne mold and can be found in high concentrations outdoors, especially after rainfall.

Where It Grows

Indoors, Cladosporium grows on damp walls, window frames, fabrics, and other moisture-damaged surfaces. High humidity can support its growth, particularly around cool surfaces. It is also commonly found on HVAC vents, ductwork, and duct liners.

Outdoors, Cladosporium grows on living and decaying plant material and in soil. Its spores are often abundant in outdoor air.

Health Considerations

Cladosporium may trigger Type I allergic reactions, including sneezing, a runny nose, itchy eyes, and worsening asthma symptoms in certain individuals. Less commonly, exposure to Cladosporium has been linked to hypersensitivity pneumonitis in susceptible individuals.

Identification

Alternaria is identified by its distinctive tail-like structure near the base of the spore. Its spores contain muriform septations, which are crosswise and lengthwise walls that divide the spore into uneven compartments. Alternaria spores may also grow in chains.

Where It Grows

Indoors, Alternaria grows on damp building materials, paper, textiles, and surfaces in areas with high humidity. Its spores are commonly found in indoor dust samples, and it can also grow on indoor plants.

Outdoors, Alternaria grows on plants, decaying vegetation, wood, and in soil. Its spores are commonly detected in outdoor air samples.

Health Considerations

Alternaria may trigger Type I allergic reactions, including sneezing, a runny nose, itchy eyes, and worsening asthma symptoms in certain individuals. Less commonly, exposure to Alternaria has been linked to hypersensitivity pneumonitis in susceptible individuals.

Identification

Chaetomium is identified by its large, brown, lemon-shaped spores, which are generally symmetrical. Its distinctive spore characteristics make it recognizable under microscopic examination.

Where It Grows

Indoors, Chaetomium growth is associated with prolonged moisture exposure and water damage caused by leaks, flooding, or other forms of water intrusion. The presence of its spores should prompt an evaluation for current or previous water problems.

Chaetomium grows on water-damaged cellulose-rich materials, such as drywall, paper, and wood. Outdoors, it grows in soil, decaying vegetation, straw, and animal dung.

Health Considerations

Chaetomium may trigger Type I allergic reactions, including sneezing, a runny nose, itchy eyes, and worsening asthma symptoms in certain individuals. Its allergy-related health effects are less extensively studied than those of Aspergillus, Alternaria, and Cladosporium. Certain Chaetomium species can also produce mycotoxins.

Identification

Basidiospores are often identified by their rounded shape and a flattened area or small appendage at one end. They vary in size and color and are frequently asymmetrical. Their characteristic attachment point is called the hilar appendage.

Where It Grows

Indoors, basidiospore-producing fungi can grow on damp wood and cause wood decay, including brown rot, white rot, and dry rot.

Outdoors, basidiospores are produced by mushrooms, puffballs, and shelf fungi. They can be found in soil, lawns, leaf litter, and on trees.

Health Considerations

Certain basidiospores may trigger Type I allergic reactions, including sneezing, a runny nose, itchy eyes, and worsening asthma symptoms in some individuals. Less commonly, exposure to certain basidiospore-producing fungi can contribute to hypersensitivity pneumonitis in susceptible individuals.

Identification

Smuts and Myxomycetes are commonly grouped together on laboratory reports because of similarities in their spore size, shape, and color. Their spores are generally round and pigmented, with surfaces that may be smooth, spiny, or patterned.

Where It Grows

Smuts do not generally grow on indoor building materials. When smut spores are found indoors, they may originate from indoor plants or outdoor sources. Myxomycetes can grow on damp, decaying wood and other organic materials.

Outdoors, smuts grow on living host plants, such as grasses and cereal crops. Myxomycetes are commonly found on decaying logs, leaves, mulch, and lawns.

Health Considerations

Certain spores in this group may trigger Type I allergic reactions, including sneezing, a runny nose, itchy eyes, and worsening asthma symptoms in some individuals. Their allergic potential varies among organisms. The health effects associated with Myxomycetes have not been extensively studied.

Identification

Torula is identified by its small, elongated spores and a distinctive cup-shaped scar that may be present at one end. These multicellular spores contain crosswise divisions called septa and may grow in chains.

Where It Grows

Indoors, Torula grows on moisture-affected materials, including paper, wood, wicker furniture, and baskets. Certain species can also cause staining on wood.

Outdoors, Torula grows on leaves, plant roots, decaying vegetation, wood, and in soil.

Health Considerations

Torula may trigger Type I allergic reactions, including sneezing, a runny nose, itchy eyes, and worsening asthma symptoms in certain individuals. However, its health effects have not been widely studied.