BackgroundHepatocellular carcinoma (HCC), or liver cancer, is the third leading cause of cancer deaths worldwide, with prevalence 16–32 times higher in developing countries than in developed countries. Aflatoxin, a contaminant produced by the fungi Aspergillus flavus and Aspergillus parasiticus in maize and nuts, is a known human liver carcinogen.ObjectivesWe sought to determine the global burden of HCC attributable to aflatoxin exposure.MethodsWe conducted a quantitative cancer risk assessment, for which we collected global data on food-borne aflatoxin levels, consumption of aflatoxin-contaminated foods, and hepatitis B virus (HBV) prevalence. We calculated the cancer potency of aflatoxin for HBV-postive and HBV-negative individuals, as well as the uncertainty in all variables, to estimate the global burden of aflatoxin-related HCC.ResultsOf the 550,000–600,000 new HCC cases worldwide each year, about 25,200–155,000 may be attributable to aflatoxin exposure. Most cases occur in sub-Saharan Africa, Southeast Asia, and China where populations suffer from both high HBV prevalence and largely uncontrolled aflatoxin exposure in food.ConclusionsAflatoxin may play a causative role in 4.6–28.2% of all global HCC cases.

Mycotoxins are toxic and carcinogenic metabolites produced by fungi that colonize food crops. The most agriculturally important mycotoxins known today are aflatoxins, which cause liver cancer and have also been implicated in child growth impairment and acute toxicoses; fumonisins, which have been associated with esophageal cancer (EC) and neural tube defects (NTDs); deoxynivalenol (DON) and other trichothecenes, which are immunotoxic and cause gastroenteritis; and ochratoxin A (OTA), which has been associated with renal diseases. This review describes the adverse human health impacts associated with these major groups of mycotoxins. First, we provide background on the fungi that produce these different mycotoxins and on the food crops commonly infected. Then, we describe each group of mycotoxins in greater detail, as well as the adverse effects associated with each mycotoxin and the populations worldwide at risk. We conclude with a brief discussion on estimations of global burden of disease caused by dietary mycotoxin exposure.

Aflatoxins, fungal toxins produced by Aspergillus flavus and Aspergillus parasiticus in a variety of food crops, are well known as potent human hepatocarcinogens. Relatively less highlighted in the literature is the association between aflatoxin and growth impairment in children. Foodborne aflatoxin exposure, especially through maize and groundnuts, is common in much of Africa and Asia--areas where childhood stunting and underweight are also common, due to a variety of possibly interacting factors such as enteric diseases, socioeconomic status, and suboptimal nutrition. The effects of aflatoxin on growth impairment in animals and human children are reviewed, including studies that assess aflatoxin exposure in utero and through breastfeeding. Childhood weaning diets in various regions of the world are briefly discussed. This review suggests that aflatoxin exposure and its association with growth impairment in children could contribute a significant public health burden in less developed countries.

Background Over 4 billion people worldwide are exposed to dietary aflatoxins, which cause liver cancer (hepatocellular carcinoma, HCC) in humans. However, the population attributable risk (PAR) of aflatoxin-related HCC remains unclear. Methods In our systematic review and meta-analysis of epidemiological studies, summary odds ratios (ORs) of aflatoxin-related HCC with 95% confidence intervals were calculated in HBV+ and HBV− individuals, as well as the general population. We calculated the PAR of aflatoxin-related HCC for each study as well as the combined studies, accounting for HBV status. Results 17 studies with 1680 HCC cases and 3052 controls were identified from 479 articles. All eligible studies were conducted in China, Taiwan, or sub-Saharan Africa. The PAR of aflatoxin-related HCC was estimated at 17% (14–19%) overall, and higher in HBV+ (21%) than HBV− (8.8%) populations. If the one study that contributed most to heterogeneity in the analysis is excluded, the summarized OR of HCC with 95% CI is 73.0 (36.0–148.3) from the combined effects of aflatoxin and HBV, 11.3 (6.75–18.9) from HBV only, and 6.37 (3.74–10.86) from aflatoxin only. The PAR of aflatoxin-related HCC increases to 23% (21–24%). The PAR has decreased over time in certain Taiwanese and Chinese populations. Conclusions In high exposure areas, aflatoxin multiplicatively interacts with HBV to induce HCC; reducing aflatoxin exposure to non-detectable levels could reduce HCC cases in high-risk areas by about 23%. The decreasing PAR of aflatoxin-related HCC reflects the benefits of public health interventions to reduce aflatoxin and HBV.

Mycotoxins, toxins produced by fungi that colonize food crops, can pose a heavy economic burden to the United States corn industry. In terms of economic burden, aflatoxins are the most problematic mycotoxins in US agriculture. Estimates of their market impacts are important in determining the benefits of implementing mitigation strategies within the US corn industry, and the value of strategies to mitigate mycotoxin problems. Additionally, climate change may cause increases in aflatoxin contamination in corn, greatly affecting the economy of the US Midwest and all sectors in the US and worldwide that rely upon its corn production. We propose two separate models for estimating the potential market loss to the corn industry from aflatoxin contamination, in the case of potential near-future climate scenarios (based on aflatoxin levels in Midwest corn in warm summers in the last decade). One model uses probability of acceptance based on operating characteristic (OC) curves for aflatoxin sampling and testing, while the other employs partial equilibrium economic analysis, assuming no Type 1 or Type 2 errors, to estimate losses due to proportions of lots above the US Food and Drug Administration (FDA) aflatoxin action levels. We estimate that aflatoxin contamination could cause losses to the corn industry ranging from $52.1 million to $1.68 billion annually in the United States, if climate change causes more regular aflatoxin contamination in the Corn Belt as was experienced in years such as 2012. The wide range represents the natural variability in aflatoxin contamination from year to year in US corn, with higher losses representative of warmer years.