Aflatoxin B2

Aflatoxin B2 (AFB2) is a toxic and potentially carcinogenic mycotoxin produced by molds such as Aspergillus flavus and Aspergillus parasiticus.  It contaminates crops like cotton, groundnuts, maize, and chilies, posing significant health and economic risks. 

Although less potent than aflatoxin B1 (AFB1), AFB2 still contributes to aflatoxicosis in humans and animals.  

Ingestion of AFB2 can lead to acute and chronic health issues, including liver cancer and immune suppression.  Chronic exposure to AFB2 can suppress the immune system, increasing susceptibility to infections and potentially exacerbating the effects of other immunotoxic agents. 

Its stability allows it to persist in food and animal feed even after processing, and it can bioaccumulate in the liver, posing long-term health risks​​​​.

What are Aflatoxins?  [10.] 

Aflatoxins are a group of highly toxic and carcinogenic compounds produced as secondary metabolites by certain molds, primarily Aspergillus flavus and Aspergillus parasiticus.  [10., 23.]

They are one type of mycotoxin, which are a larger group of toxic chemical compounds produced by molds.  

These mycotoxins are formed when the molds colonize foods like peanuts, corn, cottonseed, tree nuts, and spices under favorable temperature and humidity conditions.   [10., 22.] 

The main aflatoxins are B1, B2, G1, and G2, with aflatoxin B1 (AFB1) being the most potent and carcinogenic.  [4.] 

Their production occurs when the mold's growth is stressed, such as during drought conditions or improper crop storage. 

Aflatoxins are among the most carcinogenic substances known - they can cause acute toxicity leading to liver failure, hemorrhaging, and even death in severe cases.   [10.]  Chronic exposure increases the risk of developing liver cancer, as aflatoxins can bind to DNA and cause mutations, particularly in the p53 tumor suppressor gene.  [10., 12.]

They can also suppress the immune system, and can cause stunted growth in children.  [11., 15., 16.]

Worryingly, aflatoxins are highly stable and can persist in foods and animal feeds even after processing and cooking.  They bioaccumulate in the body over time, especially in the liver, due to their lipophilic nature and resistance to metabolic breakdown.  [1., 13., 14.] 

Aflatoxin B1 is metabolized to the reactive aflatoxin-8,9-epoxide, which binds to DNA and proteins, initiating carcinogenesis.  [16.] 

Animals fed contaminated feed can pass aflatoxin metabolites into meat, milk, and eggs, posing risks to humans consuming these products.

Anti-Aflatoxin Biomarkers

Anti-aflatoxin biomarkers are a group of compounds or metabolites that can be measured in biological samples to assess exposure to aflatoxins, which are toxic and carcinogenic metabolites produced by certain molds. 

These biomarkers provide a direct measure of internal exposure and can help evaluate the associated health risks.

A variety of biomarkers have been used to identify the presence of aflatoxins in humans and animals.  

Aflatoxin B1, known as one of the most potent and toxic aflatoxins, is one such biomarker.  

Aflatoxin B2   [10., 19.]

Aflatoxin B2 is a mycotoxin and secondary metabolite produced by the fungi Aspergillus flavus and Aspergillus parasiticus, along with other aflatoxins such as B1, G1, and G2.  It shares several properties with its more potent counterpart, aflatoxin B1, but also exhibits distinct characteristics.

AFB2 is characterized by its blue fluorescence under ultraviolet light at 425 nm.

Aflatoxin B2 (AFB2) affects crops such as cotton, groundnuts, maize, and chilies. Its contamination poses significant economic and health risks, contributing to aflatoxicosis in humans and animals. 

Ingestion of AFB2, especially through contaminated food, can lead to various acute and chronic illnesses, including liver cancer and impaired immune function. 

Health Effects of Aflatoxin B2

Aflatoxin B2, although less potent than its counterpart aflatoxin B1, still poses significant health risks due to its toxicity and potential carcinogenicity.

Toxicity and Carcinogenicity  [10., 19.]

Aflatoxin B2 is classified as a Group 2B carcinogen (possibly carcinogenic to humans) by the International Agency for Research on Cancer (IARC).

While its carcinogenic potency is lower than that of aflatoxin B1, it can contribute to the overall toxic effects of aflatoxin-contaminated food and feed products.  [19.]

The toxicity of aflatoxin B2 is primarily attributed to its ability to undergo metabolic activation, forming reactive intermediates that can bind to DNA and proteins, leading to cellular damage and potential mutagenesis.  [8.]

However, the metabolic activation pathways and the resulting DNA adducts formed by aflatoxin B2 are distinct from those of aflatoxin B1.  [9.]

Liver Damage  [18.]

 Aflatoxin B2 can contribute to the development of liver diseases, such as hepatocellular carcinoma, particularly in individuals with pre-existing liver conditions or compromised immune systems.  

Immunosuppression  [19.] 

Aflatoxin B2 has been shown to suppress immune function, increasing susceptibility to infections and potentially exacerbating the effects of other immunotoxic agents.

Developmental and Reproductive Toxicity  [20.] 

Studies have suggested that aflatoxin B2 exposure during critical developmental stages may lead to adverse effects on fetal development and reproductive health.

Aflatoxin B2 Laboratory Testing Methods

Test Information, Sample Collection and Preparation

Various biological samples can be employed to detect and quantify anti-aflatoxin biomarkers, particularly blood, urine and nasal secretions.

Blood samples are typically collected via venipuncture in a clinical setting, while urine and nasal secretion samples may be collected from the comfort of home.  

It is important to consult with the ordering provider prior to sample collection, as certain protocols may be recommended beforehand.  

Interpretation of Aflatoxin B2 Test Results

Optimal Levels of Aflatoxin B2 Test Results

Because of the high level of toxicity of aflatoxins, optimal test results indicate undetectable levels of aflatoxins.  

Clinical Significance of Elevated Aflatoxin B2

Elevated levels of aflatoxin B2 indicates recent or current exposure to aflatoxins.  However, because they are known to bioaccumulate, testing positive for the presence of aflatoxins may indicate a persistent historical exposure.  [5., 15.] 

Clinical Significance of Low Aflatoxin B2

Low or undetectable levels of aflatoxins are considered ideal.  

Aflatoxin B2 Related Biomarkers

In addition to the direct measurement of anti-aflatoxin biomarkers, other biomarkers can provide complementary information about aflatoxin exposure and its potential health effects.

Oxidative Stress Markers  [14., 21.]

Aflatoxin exposure is known to induce oxidative stress, which can lead to cellular damage and contribute to the development of various diseases. 

Biomarkers such as malondialdehyde (MDA) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) can be measured to assess oxidative stress levels and the associated risk of aflatoxin-related toxicity.  [14.] 

Liver Function Markers  [6.] 

Since the liver is a primary target organ for aflatoxin toxicity, monitoring liver function biomarkers like alanine aminotransferase (ALT), aspartate aminotransferase (AST), and bilirubin can provide insights into the extent of hepatic injury and potential liver damage caused by aflatoxin exposure.  

Inflammatory Biomarkers  [14.] 

Aflatoxin exposure can trigger inflammatory responses, and biomarkers such as C-reactive protein (CRP), interleukins (e.g., IL-6, IL-8), and tumor necrosis factor-alpha (TNF-α) can be measured to evaluate the inflammatory status and associated health risks.

Aflatoxin B1 and its Metabolites

Aflatoxin B1 (AFB1) is the most potent and well-studied aflatoxin, often used as a reference for assessing the toxicity and carcinogenicity of other aflatoxins.  The analysis of AFB1 and its metabolites, such as aflatoxin M1 (AFM1) and aflatoxin-albumin adducts, provides valuable information about exposure levels and the potential for adverse health effects.

Ochratoxins and Other Mycotoxins  [2.]

Ochratoxins, particularly ochratoxin A (OTA), are another group of mycotoxins produced by various fungal species including Aspergillus and Penicillium.  OTA is a potent nephrotoxin and has been classified as a possible human carcinogen by the International Agency for Research on Cancer (IARC).  [10.]

Co-exposure to multiple mycotoxins, including aflatoxins and ochratoxins, is common in certain regions and populations. Monitoring the levels of these mycotoxins and their biomarkers can provide a comprehensive assessment of the overall mycotoxin exposure and potential health risks.

Order Aflatoxin Testing

Click here to compare testing options and order testing for the presence of aflatoxins.