Since the 1930s, reports of Stachybotrys chartarum-related health issues in humans and animals have been published. However, there isn’t enough evidence in the scientific literature to conclusively link this mold to health problems, particularly concerning sick building syndrome. Christian Gottfried Ehrenberg published the first scientific description of the fungus in 1818. 

When examination of two newborn deaths and numerous episodes of pulmonary bleeding in kids from low-income districts of Cleveland, Ohio, showed exposure to high levels of S. chartarum as a potential cause, there was originally dispute about the organism. The Centers for Disease Control and Prevention in the United States undertook additional thorough examinations but could not establish a conclusive connection between the deaths & mold exposure. 

The Center for Disease Control, in 1994, confirmed that exposure to extremely high amounts of Stachybotrys chartarum spores caused several newborns in Cleveland to become unwell and several of them to pass away from pulmonary hemosiderosis (lung hemorrhage). However, later studies failed to demonstrate a definite link between baby fatalities & mold exposure. 

Two chemotypes of Stachybotrys chartarum can produce trichothecene mycotoxins, including satratoxin H and atranones. Exposure to S. chartarum has been linked to several specific health issues. Acute infant pulmonary hemorrhage (AIPH), a rare illness characterized by lung bleeding, was seen in Cleveland in 1993–1994; 37 newborns were given the diagnosis, & 12 of them passed afterward. Most of these infants’ homes were flooded and harbored S. chartarum and other molds. 

Other cases include the acute respiratory distress syndrome (ARDS) that two individuals experienced in Chicago in 1998 while working in a water-damaged office building polluted with S. chartarum. In addition, four adults who consumed moldy bread contaminated with S. chartarum were infected with mycotoxicosis in Kansas City in 2001. 

Natural disasters like Hurricane Katrina, which struck the Gulf Coast region of the United States in 2005, caused extensive flooding and construction damage, letting S. chartarum thrive in many devastated homes and structures.

Depending on sampling techniques, location, and other factors, the incidence of Stachybotrys chartarum in indoor air ranges from 0% to 2.5%. Like this, S. chartarum prevalence in dust samples can vary from 0% to 6.7%. Buildings with water damage, inadequate ventilation, high humidity, or materials high in cellulose are more likely to have mold in their dust. 

Kingdom: Fungi  

Phylum: Ascomycota  

Class: Sordariomycetes  

Order: Hypocreales  

Family: Stachybotryaceae  

Genus: Stachybotrys  

Species: Stachybotrys chartarum 

Mycelium: The branching filaments known as hyphae that make up the vegetative portion of the mold. S. chartarum‘s mycelium is white to grayish and occasionally covered in a slimy coating. 

Synnemata: Erect structures that protrude from the mycelium and bear conidiophores, which are reproductive structures. The synnemata of S. chartarum are dark brown to black and have branching side branches that give them a feather-like appearance. 

Conidiophores: Specialized hyphae that oversee the creation of conidial spores. The conidiophores in S. chartarum have the shape of clubs and are clustered in clusters of 4 to 10 at the end of an unbranched spore’s carrier called a stipe. Tiny droplets may also be covering them. 

When mold is disturbed, especially damp, asexual spores are expelled into the air. The ellipsoid-shaped conidia of S. chartarum have a dark brown to black appearance with solid spines. They are grouped on the conidiophores & are roughly 7–10 mm by 5–7 mm in size. 

Stachybotrys chartarum, a mold species, produces mycotoxins that serve as its main antigens and contribute to its virulence. These mycotoxins are toxic compounds that can inhibit protein synthesis and impact various organs and systems within the body. Stachybotrys chartarum can produce two chemotypes of mycotoxins: macrocyclic trichothecenes and atranones. 

The macrocyclic trichothecenes, which include roridin E, verrucarin J, satratoxin H, and isosatratoxin H, are particularly potent. They exhibit high toxicity and contribute to the adverse health effects of Stachybotrys chartarum exposure. On the other hand, atranones, including atranone A, B, C, and D, are less toxic.  

A gene cluster within Stachybotrys chartarum facilitates the biosynthesis of these mycotoxins. This cluster contains several genes encoding enzymes involved in the biosynthetic pathway of the toxins. These enzymes include polyketide synthases (PKSs), cytochrome P450 monooxygenases (CYPs), acyltransferases (ATs), dehydrogenases (DHs), and esterases (ESTs). These enzymes work together to synthesize and modify the chemical structure of the mycotoxins, contributing to their potency and virulence. 

Notably, the mycotoxin production gene cluster and other virulence factors of Stachybotrys chartarum may differ between various strains of this organism. The toxicity and virulence of various strains can vary because of this variation in gene expression & toxin generation. For instance, it has been determined that strains like 51-11 and Houston are particularly virulent in terms of mycotoxin generation & probable health impacts. 

Slow-growing Stachybotrys chartarum is an uncommon indoor air contaminant & is hardly ever detected in nature. Spores discharge into the air when the mold is mechanically disturbed, especially when wet. Not all S. chartarum strains produce mycotoxins, and some strains may eventually lose the capacity to do so. Therefore, S. chartarum, a mycotoxin-producing fungus, is only sometimes present because of high indoor humidity. 

S. chartarum has been linked to claims of health issues in humans and animals, with examples documented as far back as the 1930s. The scientific literature has not proved a connection between S. chartarum exposure and health impacts, such as sick building syndrome. Although infants in Cleveland, Ohio, have gotten sick, and some have even passed away from pulmonary hemosiderosis (lung bleeding) after exposure to high levels of S. chartarum spores, subsequent investigations failed to link mold exposure to infant deaths conclusively.

Mycotoxins, like atranones & macrocyclic trichothecenes (e.g., satratoxin H), are produced by S. chartarum. When people come into touch with or inhale material infected with S. chartarum, these mycotoxins can induce skin toxicity, respiratory discomfort, epistaxis, eye irritation, and other health problems. It is widely acknowledged that exposure to S. chartarum while living or working in a “moldy” environment increases the risk of respiratory symptoms, asthma connected to buildings, neurocognitive dysfunction, mucous membrane irritation, and immunological problems. 

Studies have shown that the macrocyclic trichothecenes, when administered intranasally or intratracheally to mice, can cause nasal and pulmonary toxicity, leading to apoptosis of olfactory sensory neurons, atrophy of the olfactory epithelium, and other changes in the frontal brain. However, it is essential to note that the concentrations of airborne spores of Stachybotrys chartarum realistically obtainable in indoor air are considered too low to produce significant clinical effects. 

Stachybotrys chartarum spores & mycotoxins are kept at bay by the skin. It offers a keratinized, acidic, and dry surface that inhibits their adhesion or absorption. Sebaceous glands, sweat glands, & hair follicles can either trap or drain out mycotoxins and spores.

Mucus is produced by mucous membranes, like those in the urogenital, digestive, and respiratory tracts, and it can capture & release these particles—the mucous membranes’ cilia aid in removing mycotoxins & spores. 

The innate immune system responds quickly to Stachybotrys chartarum. Chemicals present on or inside the mold might be recognized by pattern recognition receptors, like dectin-1 & toll-like receptors (TLRs).

Pro-inflammatory cytokines, chemokines, & antimicrobial peptides are produced because of signaling pathways activated by PRRs. Phagocytes can absorb and eliminate the mold particles, including neutrophils, macrophages, & dendritic cells. A set of proteins called the complement system can promote phagocytosis and mold killing.

Stachybotrys chartarum elicits a targeted memory response from the adaptive immune system. To neutralize the mold particles, promote their phagocytosis, or activate the complement system, B cells create antibodies that can identify & bind to specific antigens on the mold particles. The immune response depends heavily on T cells, particularly cytotoxic T cells (Tc) & helper T cells (Th).

Th cells release cytokines that control the immune response, encouraging humoral immunity and allergic reactions (Th2), mucosal immunity and inflammation (Th17), or cell-mediated immunity (Th1). Tc cells directly eliminate Stachybotrys chartarum antigen-presenting infected cells. 

B cell-produced antibodies serve a part in humoral immunity to S. chartarum. These antibodies can opsonize the mold particles for phagocytosis, neutralize them, or trigger the complement system. Antibodies can stop mold from adhering or invading, reducing its negative consequences. 

Cell-mediated immunity against S. chartarum is mediated by T cells, particularly Th1 & Th17 cells. Th1 cells release cytokines that boost phagocyte destruction and promote the generation of antibodies. Th17 cells trigger the production of antimicrobial peptides & draw immune cells to the infection site. S. cytotoxic T lymphocytes directly kill chartarum-infected host cells. 

Allergic reactions: People allergic to mold often have allergy symptoms after exposure to Stachybotrys chartarum. Red, itchy eyes, respiratory problems including wheezing, coughing, or sinus congestion, a skin rash, a sore throat, & headaches are some examples of these symptoms. 

Exacerbation of asthma: Asthmatics exposed to mold, particularly Stachybotrys chartarum, may notice worsening symptoms. Breathlessness, tightness in the chest, wheezing, and protracted coughing may result from this. 

Mycotoxicosis: Trichothecenes, which Stachybotrys chartarum can produce, can potentially have harmful effects on the body. The illness brought on by ingesting or breathing these mycotoxins is known as mycotoxicosis. Many other symptoms might occur, such as diarrhea, nausea, vomiting, abdominal pain, fever, weakness, joint pain, muscle cramps, nerve pain, sleeplessness, depression, anxiety, & cognitive issues. The relationship between mycotoxins & human disease, however, is still debatable and needs more study. 

Pulmonary hemorrhage: In a small percentage of cases, exposure to Stachybotrys chartarum has been linked to pulmonary hemorrhage, a form of lung bleeding. Infants who lived in houses with mold contamination have shown this. Blood in the cough, breathing difficulties, and anemia are possible symptoms. Further research is necessary since the connection between S. chartarum and pulmonary hemorrhage must still be established. 

Culture Method: This diagnostic method involves culturing samples collected from suspected sources of Stachybotrys chartarum contamination. Selective media, such as rice cultures or gypsum board cultures, can be used to promote mold growth. The appearance of colonies on the culture plates, such as black or dark-colored colonies with a slimy texture, can suggest the presence of S. chartarum. 

IgE Antibody Allergy Test: This test involves analyzing a blood sample to determine if the individual is allergic to S. chartarum. It detects the presence of specific IgE antibodies released by the immune system in response to exposure to the mold. Techniques such as ELISA, immunoblotting, or radioallergosorbent test (RAST) can be employed for antibody testing. This test can indicate past or present exposure to S. chartarum but cannot differentiate between allergic sensitization and infection. 

Environmental Relative Moldiness Index (ERMI): ERMI is an indoor air quality test developed by the U.S. Environment Protection Agency & the U.S. Department of Housing and Urban Development. It uses DNA-based technology to assess the presence and quantity of mold species associated with water damage in tested households. S. chartarum is one of the 36 mold species screened by ERMI, providing valuable information about mold contamination levels. 

Histopathology: Histopathological examination is conducted on biopsy samples to observe tissue changes associated with S. chartarum exposure. It helps identify characteristic features such as inflammation, necrosis, and tissue damage caused by the mold. Histopathology is particularly useful in cases where direct contact or inhalation of S. chartarum is suspected to have caused localized or systemic effects. 

Mycotoxin Testing: This diagnostic method involves detecting and measuring mycotoxins produced by S. chartarum cells. Techniques like liquid chromatography-tandem mass spectrometry (LC-MS/MS) or high-performance liquid chromatography (HPLC), and gas chromatography-mass spectrometry (GC-MS) can be employed to analyze samples for mycotoxins. This testing can indicate exposure to S. chartarum but cannot differentiate between acute and chronic toxicity caused by mycotoxin exposure. 

• Identify and address any moisture or water intrusion sources in buildings promptly—repair leaks in plumbing, roofs, or windows. Improve ventilation and airflow in areas prone to dampness or condensation. Maintain relative humidity below 50% in indoor environments. 

• Dry any damp materials, surfaces, or belongings within 24- 48 hours to avoid mold growth. Use fans, dehumidifiers, or natural ventilation to expedite the drying process. Ensure proper drainage around buildings to prevent water accumulation near foundations—direct water away from the structure through appropriate grading and gutter systems. 

• When handling mold-contaminated materials or conducting cleanup activities, use proper PPE, including gloves, goggles, and masks, to minimize exposure to mold spores & mycotoxins.

• Clean and maintain areas prone to mold growth, such as bathrooms and kitchens, regularly using appropriate cleaning agents and methods. Remove visible mold promptly using physical methods like scrubbing and wiping. 

Stachybotrys Chartarum – an overview | ScienceDirect Topics

7 Facts about Stachybotrys Chartarum | O2 Mold Testing 

Stachybotrys – Allergy, Health Symptoms & Treatment | Mold Busters (bustmold.com)