Mycotoxins: Growing Health Concerns?

Mycotoxins are biotoxins that occur in crops and feeds and are frequently found in spoiled foods (Stroka and Gonçalves 2019). Secondary metabolites of toxin-producing fungi, mycotoxins cause about 25% of crop damage worldwide (Marin, Ramos, Cano-Sancho, and Sanchis 2013).

Significant exposure to mycotoxins by inhalation, ingestion, or skin contact has substantial impact on both human and animal health. The most common mycotoxins are produced by fungal genera, such as Fusarium, Clavicepts, Alternaria, Aspergillus, and Penicillium. The primary mycotoxins ingested by children and adults are aflatoxins (AFs), deoxynivalenol (DON), fumonisins (FBs), ochratoxins (OTA), and patulin (PAT) (Raiola, Tenore, Manyes, Meca, and Ritieni 2015). The commodities most susceptible to containing mycotoxins are grains, tree nuts, fruit, and seeds (Patriarca and Pinto 2017).

In the United States, significant mycotoxin exposure is uncommon thanks to advanced agricultural and food processing methods, careful biomonitoring, and enforced regulatory standards. In contrast, in underdeveloped countries, crop loss and mycotoxin contamination of the food supply significantly impact human and animal health and the ability to export food products. In fact, mycotoxin contamination is an emerging reason to reject maize and wheat being imported into Europe (Moretti, Pascale, and Logrieco 2019). Myco-toxin exposure can increase with climate change; insect/pest damage; and/or agriculture, storage, and food processing issues.

Ingesting dosages that exceed provisional maximum tolerable daily intake can result in gastrointestinal injury or other organ injury that can at times lead to death (Raiola, Tenore, Manyes, Meca, and Ritieni 2015). Studying a piglet model, data suggest chronic ingestion (5 weeks) of DON (3 mg/kg) and FB (6 mg/kg) can result in specific organ damage, endocrine disruption, neurotoxicity, immunosuppression, cancer, and birth defects (Bracarense, Lucioli, Grenier, et al. 2012) (Gonçalves and Stroka 2016).

What might be a more accurate way of assessing and managing risk, especially for the very young, the malnourished, or people with chronic disease, who lack a normal ability to metabolize these toxins (Bracarense, Lucioli, Grenier, et al. 2012)? Young children have immature metabolism/detoxification systems and higher intakes of food per body weight. People of any age with malnutrition or chronic disease or those who are on drug treatments that inhibit mycotoxin metabolism are also at increased risk (Barac 2019).

Fundamentally, the biomonitoring within the food supply involves critical points of preharvest, harvest, and postharvest practices intended to minimize or actually decontaminate mycotoxins in raw materials and finished processed products (Patriarca and Pinto 2017). Regardless, careful biomonitoring and adjustment of the maximum permitted levels for foods frequently ingested by young children and the sick and careful refrigeration of nut butters, breads, and other products likely to grow toxigenic mold at room temperature should be considered important food safety measures in child and health-care settings.

A recent U.S. Food and Drug Administration (FDA) survey of 215 samples of infant and toddler foods from three geographical regions in the United States indicated the concentrations of detected mycotoxins were below the current FDA requirements and guidance levels (Zhang, Flannery, Oles, and Adeuya 2018).

However, a snapshot of mycotoxin contamination of products in various African regions depicts a different picture. A 10-year review of many foods in Southern Africa indicates a virtual absence of agricultural or regulatory control of mycotoxins in the food supply, particularly in maize, peanuts, and some fruit juices (Misihairabgwi, Ezekiel, Sulyok, Shephard, and Krska 2017). Within nearly 200 Nigerian fermented foods, evidence indicates at least 82% of the samples contained one or more of 23 different mycotoxins at levels that represented potential health risks (Adekoya, Njobeh, Obadina, et al., 2017). These findings within selected regions of Africa are alarming, especially since some of these areas have adopted European standards. However, execution of legislation relative to mycotoxin controls is flexible and often voluntary in these areas.

From a global perspective, biomonitoring is expensive and requires careful batch testing, particularly for imported foods. Many developed countries have unique standards to mitigate mycotoxin contamination within agricultural settings and foods and have developed detoxification technologies and strategies to eliminate these substances (Hassan and Zhou 2018). Yet, from a global public health perspective, some questions are certainly pertinent to protect high-risk populations, such as infants and immuno-suppressed individuals.

Roger Clemens, DrPH, CFS, Contributing Editor
Adjunct Professor, Univ. of Southern California’s School of Pharmacy, Los Angeles, Calif.
[email protected]

Peter Pressman, MD, is director, The Daedalus Foundation
([email protected]).