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one of the most prevalent fungi

mycotoxin growing on moldy corn (maize) grain

Fumonisin B3 (FB3), a less commonly studied but significant mycotoxin, is an important marker in Total Tox Burden panels, reflecting potential exposure to toxins produced by Fusarium species, predominantly found in maize and its by-products. Structurally, FB3 is similar to other fumonisins like B1 and B2, but it is often present at lower concentrations in contaminated foods. Its inclusion in tox burden assessments is crucial due to its potential health implications. Although FB3's toxicity is generally considered to be lower than that of fumonisin B1, it still poses health risks, particularly hepatotoxic and nephrotoxic effects, and it may play a role in esophageal cancer and neural tube defects. The presence of FB3 in a Total Tox Burden panel indicates exposure to Fusarium toxins and necessitates the examination of dietary intake, especially corn-based products, which are the primary source. Preventive strategies focus on agricultural practices to limit fungal contamination and post-harvest interventions to reduce mycotoxin levels. Current research into FB3's biological effects and its interactions with other mycotoxins is essential for understanding its full impact on human health and for the development of more effective detection and detoxification methods. This is particularly relevant as global climate change may alter the distribution and prevalence of Fusarium species, potentially leading to increased exposure to fumonisins, including FB3.

What is Fumonisin B3? Fumonisin B3 (FB3) is a type of mycotoxin produced mainly by Fusarium species of mold, which commonly contaminate corn, maize-based products, and other grains. Fumonisins occur in several forms (B1, B2, and B3 being the most common), and they often appear together in contaminated food. While Fumonisin B1 is considered the most toxic and well-studied, Fumonisin B3 can also contribute to adverse health effects and overall toxic burden, especially when exposure is chronic. Testing urine for FB3 provides a way to assess recent dietary exposure to fumonisins. Why Does Fumonisin B3 Exposure Matter? Fumonisins interfere with a key metabolic pathway involving sphingolipids—fats essential for building cell membranes and supporting nerve and brain function. By disrupting this pathway, fumonisins may: Alter cell signaling and communication Weaken intestinal barrier integrity (“leaky gut”) Contribute to immune dysfunction Increase risk for certain chronic health conditions Because fumonisins frequently contaminate corn, cereals, and animal feeds, exposure can be widespread in populations with diets high in maize-based products. Health Effects of Fumonisins (including FB3) Research on FB3 is more limited than FB1, but studies suggest that fumonisins as a group may be associated with: Digestive problems (abdominal pain, diarrhea, nausea) Nutrient malabsorption and impaired gut health Immune system suppression Liver and kidney stress Possible links to neurotoxicity (nerve and brain effects) Increased risk of certain cancers in animal studies (especially esophageal and liver cancer, mainly associated with FB1 but potentially influenced by FB3 as well) Why Test for Fumonisin B3? Testing for FB3 can help identify hidden mold toxin exposure, especially if you: Eat a diet high in corn, maize, or processed foods containing corn Experience chronic digestive issues, fatigue, or immune weakness without a clear cause Live in areas where grain storage is prone to warm and humid conditions that favor Fusarium growth Are completing a Total Tox Burden or Mycotoxins panel, where multiple mold toxins are measured together Want to monitor detoxification progress or confirm whether dietary changes reduce toxin levels Key Takeaway Elevated Fumonisin B3 levels in urine point to recent exposure to Fusarium mold toxins, most often through contaminated corn or grains. While FB3 is considered less toxic than FB1, it still adds to the body’s cumulative mycotoxin load and may contribute to gut, immune, and systemic health problems over time. Choosing high-quality grains, improving food storage, and limiting processed corn-based foods can help reduce fumonisin exposure and support long-term health.

Fungitell® is the first and only FDA-cleared and CE-marked rapid in vitro diagnostic screening test for invasive fungal infections (IFI), including Candida, Aspergillus, and Pneumocystis. It detects (1→3)-β-D-Glucan in serum. This assay aids in the presumptive diagnosis of fungal infections and should be used alongside other diagnostic procedures. Glucan Value Interpretation - Values <60 pg/mL: Considered negative, indicating the presumptive absence of fungal infection. - Values between 60 and <80 pg/mL: Considered indeterminate. - Values ≥80 pg/mL: Considered positive, indicating the presumptive presence of a fungal infection. Certain fungal species that do not produce or produce low levels of (1→3)-β-D-glucan, such as Cryptococcus, Absidia, Mucor, Rhizopus, and the yeast phase of Blastomyces dermatitidis, may not be detected by this assay. Importance of (1→3)-β-D-Glucan Assay Invasive fungal infections (IFI) are increasingly common, particularly among immunocompromised patients. Most pathogenic fungi contain (1→3)-β-D-glucan in their cell walls, which is released into the bloodstream during infection. Monitoring serum (1→3)-β-D-glucan levels provides a useful surrogate marker for IFI. Fungal Trends & Statistics The rise in invasive fungal infections is linked to more aggressive medical treatments, such as immunosuppressive therapy and intensive care unit (ICU) care. Annually, there are an estimated 40-60 thousand cases of invasive fungal infections in the USA. Candidemia is the fourth leading cause of nosocomial bloodstream infections and the third most common ICU bloodstream infection. Traditional microbial culture techniques, while widely used, have low sensitivity and long incubation times, underscoring the need for faster and more sensitive diagnostic methods. Since its FDA clearance in 2004, Fungitell® has gained popularity due to its high sensitivity, high negative predictive value, and rapid results. Early diagnosis and treatment have been shown to increase survival rates in cases of candidal shock. Why Test for (1→3)-β-D-Glucan? Most pathogenic fungi have (1→3)-β-D-glucan in their cell walls. During infection, small but detectable quantities of this glucan are released into the bloodstream. Detecting elevated levels of (1→3)-β-D-glucan aids in the presumptive diagnosis of invasive fungal infections (IFI) in at-risk patients. At-Risk Patient Populations - Cancer patients undergoing chemotherapy - Stem cell and organ transplant patients - Burn patients - HIV patients - ICU patients

a byproduct of Aspergillus and other fungal species

a byproduct of Aspergillus and other fungal species

A conjugate of furancarboxylic acid and the amino acid glycine.

A conjugate of furancarboxylic acid and the amino acid glycine.

Aspergillus

A conjugate of furancarboxylic acid and the amino acid glycine.

Aspergillus

ubiquitous fungi commonly found in soils and plants.

The Fusarium Proliferatum/Moniliforme IgG test measures levels of IgG antibodies in your blood that are specific to Fusarium proliferatum and Fusarium moniliforme—two types of environmental molds (fungi) often found in soil, water-damaged buildings, and decaying plant material. Why It Matters: This test is typically ordered to assess immune system exposure to these molds—not to diagnose an active infection or allergy. Elevated IgG levels suggest prior or ongoing exposure, but they do not confirm disease or mold-related illness by themselves. Fusarium species can sometimes be associated with: Chronic respiratory symptoms Hypersensitivity pneumonitis Environmental mold exposure syndromes However, the presence of IgG antibodies only tells us that your immune system has recognized and responded to the mold—not whether that response is causing symptoms or illness. Important Limitations: Elevated IgG does not necessarily mean you have a current infection or disease. It is not used to diagnose mold toxicity or acute mold allergies. The test is best interpreted by specialists who understand the clinical context, such as infectious disease physicians or allergists. Reference ranges are based on people without unusual mold exposure and carry no direct disease significance. When Is This Test Helpful? This test may be considered when: You have ongoing respiratory issues with suspected environmental causes There’s a history of significant mold exposure (e.g., living in a water-damaged building) You're being evaluated for hypersensitivity pneumonitis or chronic mold-related conditions Next Steps: If you’ve had this test done and are unsure what the results mean, consult your healthcare provider—especially if you have unexplained respiratory symptoms or known mold exposure.

Autoimmune Association: Systemic sclerosis or inflammatory bowel disease.