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In recent years, there has been an increasing interest in investigating the carcinogenicity of mycotoxins in humans. This systematic review aims to provide an overview of data linking exposure to different mycotoxins with human cancer risk. Publications (2019 and earlier) of case–control or longitudinal cohort studies were identified in PubMed and EMBASE. These articles were then screened by independent reviewers and their quality was assessed according to the Newcastle–Ottawa scale. Animal, cross‐sectional, and molecular studies satisfied criteria for exclusion. In total, 14 articles were included: 13 case–control studies and 1 longitudinal cohort study. Included articles focused on associations of mycotoxin exposure with primary liver, breast, and cervical cancer. Overall, a positive association between the consumption of aflatoxin‐contaminated foods and primary liver cancer risk was verified. Two case–control studies in Africa investigated the relationship between zearalenone and its metabolites and breast cancer risk, though conflicting results were reported. Two case–control studies investigated the association between hepatocellular carcinoma and fumonisin B1 exposure, but no significant associations were observed. This systematic review incorporates several clear observations of dose‐dependent associations between aflatoxins and liver cancer risk, in keeping with IARC Monograph conclusions. Only few human epidemiological studies investigated the associations between mycotoxin exposures and cancer risk. To close this gap, more in‐depth research is needed to unravel evidence for other common mycotoxins, such as deoxynivalenol and ochratoxin A. The link between mycotoxin exposures and cancer risk has mainly been established in experimental studies, and needs to be confirmed in human epidemiological studies to support the evidence‐based public health strategies. [ABSTRACT FROM AUTHOR]

Abstract: Mycotoxins are toxic secondary metabolites of fungal origin and contaminate agricultural commodities before or under post-harvest conditions. They are mainly produced by fungi in the Aspergillus, Penicillium and Fusarium genera. When ingested, inhaled or absorbed through the skin, mycotoxins will cause lowered performance, sickness or death on humans and animals. Factors that contribute to mycotoxin contamination of food and feed in Africa include environmental, socio-economic and food production. Environmental conditions especially high humidity and temperatures favour fungal proliferation resulting in contamination of food and feed. The socio-economic status of majority of inhabitants of sub-Saharan Africa predisposes them to consumption of mycotoxin contaminated products either directly or at various points in the food chain. The resulting implications include immuno-suppression, impaired growth, various cancers and death depending on the type, period and amount of exposure. A synergistic effect between mycotoxin exposure and some important diseases in the continent such as malaria, kwashiorkor and HIV/AIDS have been suggested. Mycotoxin concerns have grown during the last few decades because of their implications to human and animal health, productivity, economics of their management and trade. This has led to development of maximum tolerated limits for mycotoxins in various countries. Even with the standards in place, the greatest recorded fatal mycotoxin-poisoning outbreak caused by contamination of maize with aflatoxins occurred in Africa in 2004. Pre-harvest practices; time of harvesting; handling of produce during harvesting; moisture levels at harvesting, transportation, marketing and processing; insect damage all contribute to mycotoxin contamination. Possible intervention strategies include good agricultural practices such as early harvesting, proper drying, sanitation, proper storage and insect management among others. Other possible interventions include biological control, chemical control, decontamination, breeding for resistance as well as surveillance and awareness creation. There is need for efficient, cost-effective sampling and analytical methods that can be used for detection analysis of mycotoxins in developing countries. [Copyright &y& Elsevier]

Summary Background Aflatoxins are fungal metabolites that frequently contaminate staple foods in much of sub-Saharan Africa, and are associated with increased risk of liver cancer and impaired growth in young children. We aimed to assess whether postharvest measures to restrict aflatoxin contamination of groundnut crops could reduce exposure in west African villages. Methods We undertook an intervention study at subsistence farms in the lower Kindia region of Guinea. Farms from 20 villages were included, ten of which implemented a package of postharvest measures to restrict aflatoxin contamination of the groundnut crop; ten controls followed usual postharvest practices. We measured the concentrations of blood aflatoxin-albumin adducts from 600 people immediately after harvest and at 3 months and 5 months postharvest to monitor the effectiveness of the intervention. Findings In control villages mean aflatoxin-albumin concentration increased postharvest (from 5·5 pg/mg [95% CI 4·7-6·1] immediately after harvest to 18·7 pg/mg [17·0-20·6] 5 months later). By contrast, mean aflatoxin-albumin concentration in intervention villages after 5 months of groundnut storage was much the same as that immediately postharvest (7·2 pg/mg [6·2-8·4] vs 8·0 pg/mg [7·0-9·2]). At 5 months, mean adduct concentration in intervention villages was less than 50% of that in control villages (8·0 pg/mg [7·2-9·2] vs 18·7 pg/mg [17·0-20·6], p<0·0001). About a third of the number of people had non-detectable aflatoxin-albumin concentrations at harvest. At 5 months, five (2%) people in the control villages had non-detectable adduct concentrations compared with 47 (20%) of those in the intervention group (p<0·0001). Mean concentrations of aflatoxin B1 in groundnuts in household stores in intervention and control villages were consistent with measurements of aflatoxin-albumin adducts. Interpretation Use of low-technology approaches at the subsistence-farm level in sub-Saharan Africa could substantially reduce the disease burden caused by aflatoxin exposure. [ABSTRACT FROM AUTHOR]

Humans continue to be constantly exposed to mycotoxins, mainly through oral exposure (dietary), inhalation, or dermal contact. Recently, it has been of increasing interest to investigate mycotoxin-linked carcinogenicity. This systematic review was conducted to synthesize evidence of the association between mycotoxin-linked mutations and the risk of cancer, to provide an overview of the data linking exposure to different mycotoxins with human cancer risk, and to provide an update on current research on the risk of cancer associated with human exposure to mycotoxins. PRISMA guidelines were used when conducting the systematic review. PubMed, MEDLINE, and CINAHL electronic databases were comprehensively searched to extract the relevant studies published from inception to May 2022. A total of sixteen relevant studies (4907 participants) were identified and included in this review. Of these, twelve studies were from Asia, while four of the studies were conducted in Africa. The overall meta-analysis result found no significant association, although some of the studies confirmed an association between mycotoxin-linked mutations and primary liver cancer risk. Mainly, the experimental studies have shown associations between mycotoxin-linked mutations and cancer risk, and there is a need for researchers to confirm these links in epidemiological studies in order to guide public health policies and interventions.

Mycotoxins are toxigenic fungal secondary metabolites and known carcinogens that pose a significant threat to economies, trade, health and compromises food safety. Favourable environmental conditions on the African continent encourage the proliferation of fungal species, increasing the possibility of attendant mycotoxins to be present in foods, a situation that aggravates challenges to address them. Due to the susceptibility of common food crops to these toxins and the general inability of some conventional food processes to eliminate them, they are found in derived/processed foods. Detoxification and reduction of mycotoxins in the food chain still remains a significant topic necessitating a sustainable, affordable and effective strategy for mycotoxin control. Fermentation of food confers desirable properties and improves food quality. This food processing technique is also a notable inexpensive mycotoxin decontamination strategy that can be explored not only to improve the constituents in food, but equally reduce and at best eliminate mycotoxins. In the absence of sophisticated monitoring and prevention mechanisms in Africa, exploiting fermentation would be vital in improving nutrition and ensuring food safety. While this processing technique generally favours mycotoxin reduction, preventing the occurrence of these toxins in crops, effective handling and storage practices before fermentation may ensure complete prevention of the heinous effect of these toxins on human health. [ABSTRACT FROM AUTHOR]