Aflatoxins and growth impairment: a review

Effect of homemade peanut oil consumption during pregnancy on low birth weight and preterm birth outcomes: a cohort study in Southwestern China

BACKGROUND

Homemade peanut oil is widely consumed in rural areas of Southwestern China, which is easily contaminated by aflatoxins (AFs) and associated with adverse birth outcomes.

OBJECTIVE

To identify the effect of exposure to homemade peanut oil consumption on low birth weight (LBW), preterm birth (PB) and other associated factors.

METHODS

A prospective cohort study was conducted among pregnant women in Guangxi province, Southwestern China. Information of all eligible women on homemade peanut oil consumption and potential factors associated with LBW and PB was collected, and all were followed up until delivery. The effect of homemade peanut oil exposure was analyzed using multiple logistic regression models using the directed acyclic graph (DAG) approach.

RESULTS

Of 1611 pregnant women, 1316 (81.7%) had consumed homemade peanut oil, and the rates of LBW and PB were 9.7% and 10.0%, respectively. Increased risks of LBW and PB in women with homemade peanut oil consumption were found with aORs of 1.9 (95% CI 1.1-3.2) and 1.8 (95% CI 1.1-3.0), respectively. Women with a history of PB or LBW were 3-5 times more likely to have higher rates of LBW or PB compared with those without this type of history. The odds of PB were approximately double in those taking medicine during pregnancy. Advanced maternal age, lack of physical exercise during pregnancy, passive smoking, or pregnancy complications were also more likely to have a higher risk of LBW.

CONCLUSIONS

Homemade peanut oil consumption was a potential risk factor for both LBW and PB, of which health authorities who are responsible for food safety of the country should pay more attention to providing recommendation for oil consumption during pregnancy.

Association between low maternal serum aflatoxin B1 exposure and adverse pregnancy outcomes in Mombasa, Kenya, 2017-2019: A nested matched case-control study

We examined the association between serum aflatoxin B1-lysine adduct (AFB1-lys) levels in pregnant women and adverse pregnancy outcomes (low birthweight, miscarriage and stillbirth) through a nested matched case-control study of pregnant women enroled at ≤28 weeks' gestation in Mombasa, Kenya, from 2017 to 2019. Cases comprised women with an adverse birth outcome, defined as either delivery of a singleton infant weighing <2500 g, or a miscarriage, or a stillbirth, while controls were women who delivered a singleton live infant with a birthweight of ≥2500 g. Cases were matched to controls at a ratio of 1:2 based on maternal age at enrolment, gestational age at enrolment and study site. The primary exposure was serum AFB1-lys. The study included 125 cases and 250 controls. The median gestation age when serum samples were collected was 23.0 weeks (interquartile range [IQR]: 18.1-26.0) and 23.5 (IQR: 18.1-26.5) among cases and controls, respectively. Of the 375 tested sera, 145 (38.7%) had detectable serum AFB1-lys: 36.0% in cases and 40.0% in controls. AFB1-lys adduct levels were not associated with adverse birth outcomes on multivariable analysis. Mid-upper arm circumference was associated with a 6% lower odds of adverse birth outcome for every unit increase (p = 0.023). Two-fifths of pregnant women had detectable levels of aflatoxin midway through pregnancy. However, we did not detect an association with adverse pregnancy outcomes, likely because of low serum AFB1-lys levels and low power, restricting meaningful comparison. More research is needed to understand the public health risk of aflatoxin in pregnant women to unborn children.

Dietary aflatoxins exposure, environmental enteropathy, and their relation with childhood stunting

Childhood stunting is a global phenomenon affecting more than 149 million children under the age of 5 worldwide. Exposure to aflatoxins (AFs) in utero, during breastfeeding, and consumption of contaminated food affect the gut microbiome, resulting in intestinal dysfunction and potentially contributing to stunting. This review explores the potential relationship between AF exposure, environmental enteropathy and childhood stunting. AFs bind to DNA, disrupt protein synthesis and elicit environmental enteropathy (EE). An EE alters the structure of intestinal epithelial cells, impairs nutrient uptake and leads to malabsorption. This article proposes possible intervention strategies for researchers and policymakers to reduce AF exposure, EE and childhood stunting, such as exposure reduction, the implementation of good agricultural practices, dietary diversification and improving environmental water sanitation and hygiene.

Efficacy of atoxigenic Aspergillus flavus from southern China as biocontrol agents against aflatoxin contamination in corn and peanuts

Aspergillus flavus is a ubiquitous facultative pathogen that routinely infects important crops leading to formation of aflatoxins during crop development and after harvest. Corn and peanuts in warm and/or drought-prone regions are highly susceptible to aflatoxin contamination. Controlling aflatoxin using atoxigenic A. flavus is a widely adopted strategy. However, no A. flavus genotypes are currently approved for use in China. The current study aimed to select atoxigenic A. flavus endemic to Guangxi Zhuang Autonomous Region with potential as active ingredients of aflatoxin biocontrol products. A total of 204 A. flavus isolates from corn, peanuts, and field soil were evaluated for ability to produce the targeted mycotoxins. Overall, 57.3% could not produce aflatoxins while 17.15% were incapable of producing both aflatoxins and CPA. Atoxigenic germplasm endemic to Guangxi was highly diverse, yielding 8 different gene deletion patterns in the aflatoxin and CPA biosynthesis gene clusters ranging from no deletion to deletion of both clusters. Inoculation of corn and peanuts with both an aflatoxin producer and selected atoxigenic genotypes showed significant reduction (74 to 99%) in aflatoxin B1 (AFB1) formation compared with inoculation with the aflatoxin producer alone. Atoxigenic genotypes also efficiently degraded AFB1 (61%). Furthermore, atoxigenic isolates were also highly efficient at reducing aflatoxin concentrations even when present at lower concentrations than aflatoxin producers. The use of multiple atoxigenics was not always as effective as the use of a single atoxigenic. Effective atoxigenic genotypes of A. flavus with known mechanisms of atoxigenicity are demonstrated to be endemic to Southern China. These A. flavus may be utilized as active ingredients of biocontrol products without concern for detrimental impacts that may result from introduction of exotic fungi. Field efficacy trials in the agroecosystems of Southern China are needed to determine the extent to which such products may allow the production of safer food and feed.

Study protocol to assess aflatoxin M1 health risks versus benefits of dairy consumption in Ethiopian children: an epidemiological trial and risk-benefit analysis

INTRODUCTION

In Sidama, Ethiopia, animal-source foods can be difficult to access. Milk has important nutrients for child growth, but carries the risk of aflatoxin M1 (AFM1) contamination. AFM1 is a metabolite of the mycotoxin aflatoxin B1 (AFB1) in dairy feed; cows secrete AFM1 in milk when their feed contains AFB1 produced by Aspergillus fungi in maize, nuts and oilseeds. It is unknown whether AFM1 compromises child growth and health.

METHODS AND ANALYSIS

This protocol paper describes our study in Sidama to determine the impact of milk consumption and AFM1 on child growth in the first 18 months of life. We will collect baseline and end-line data on dairy production, socioeconomic and nutritional factors of 1000 dairy-owning households with children ages 6-18 months at baseline; and gather samples of milk and dairy feed and child anthropometrics. We will conduct phone interviews every 6 months to ascertain changes in practices or child health. Dairy feed will be tested for AFB1; milk for AFM1, pathogens and nutrients. Controlling for herd size, socioeconomic, nutritional and behavioural factors, we will determine the association between child anthropometrics and milk consumption, as well as AFM1 exposure. We will examine whether AFM1 exposure affects child growth in the first 18 months of life, and weigh the benefits and risks of milk consumption.

ETHICS AND DISSEMINATION

The protocol is approved by the Institutional Review Boards of the Ethiopian Public Health Institute (EPHI-IRB-481-2022), Michigan State University (STUDY00007996) and International Food Policy Research Institute (DSGD-23-0102). Written informed consent will be obtained from all participants, who may withdraw from the study at any time. Confidentiality of collected data will be given high priority during each stage of data handling. The study's findings will be disseminated through stakeholder workshops, local and international conferences, journal articles and technical reports.

Advancing Global Health Surveillance of Mycotoxin Exposures using Minimally Invasive Sampling Techniques: A State-of-the-Science Review

Mycotoxins are a heterogeneous group of toxins produced by fungi that can grow in staple crops (e.g., maize, cereals), resulting in health risks due to widespread exposure from human consumption and inhalation. Dried blood spot (DBS), dried serum spot (DSS), and volumetric tip microsampling (VTS) assays were developed and validated for several important mycotoxins. This review summarizes studies that have developed these assays to monitor mycotoxin exposures in human biological samples and highlights future directions to facilitate minimally invasive sampling techniques as global public health tools. A systematic search of PubMed (MEDLINE), Embase (Elsevier), and CINAHL (EBSCO) was conducted. Key assay performance metrics were extracted to provide a critical review of the available methods. This search identified 11 published reports related to measuring mycotoxins (ochratoxins, aflatoxins, and fumonisins) using DBS/DSS and VTS assays. Multimycotoxin assays adapted for DBS/DSS and VTS have undergone sufficient laboratory validation for applications in large-scale population health and human biomonitoring studies. Future work should expand the number of mycotoxins that can be measured in multimycotoxin assays, continue to improve multimycotoxin assay sensitivities of several biomarkers with low detection rates, and validate multimycotoxin assays across diverse populations with varying exposure levels. Validated low-cost and ultrasensitive minimally invasive sampling methods should be deployed in human biomonitoring and public health surveillance studies to guide policy interventions to reduce inequities in global mycotoxin exposures.

Level of exposure to aflatoxins during pregnancy and its association with adverse birth outcomes in Africa: a meta-analysis

BACKGROUND

Aflatoxins are various poisonous carcinogens and mutagens produced by Aspergillus species. Exposure to aflatoxins during pregnancy results in adverse birth outcomes. This meta-analysis was carried out to determine the estimates of how much aflatoxin is harmful to the pregnancy and its outcome, including birthweight, birth length, low birthweight (LBW), small for gestational age (SGA), stunting, poverty, food insecurity, income, pesticides and stillbirth, in an African context.

METHODS

Both published and unpublished studies in Africa were searched on MEDLINE, PubMed, Embase, SCOPUS, Web of Science and Google Scholar. Stata version 18.2 software was used for cleaning and analysis. The prevalence with a 95% confidence interval (CI) was estimated using the random effects model and a forest plot was used to present the findings. In addition, the heterogeneity of the study was assessed using Cochrane I2 statistics and publication bias was assessed using Egger's intercept and funnel plot.

RESULTS

This review included 28 studies with a total of 6283 pregnant women and newborns. The analysis showed the overall level of exposure to aflatoxins was 64% (95% CI 48 to 78, τ2=0.66, I2=99.34%, p=0.001). In the subgroup analysis by publication year, the highest level of exposure to aflatoxins (82% [95% CI 69 to 92]) was observed among studies published from 2020 to 2023. This study also found that exposure to aflatoxins during pregnancy had an association with prematurity, LBW, SGA and stillbirth.

CONCLUSIONS

The data analysed in this study indicated that three of every five pregnant women had exposure to aflatoxins in Africa. Moreover, pregnant women exposed to aflatoxins had a higher likelihood of having a LBW and SGA newborn. Thus governments and all stakeholders should initiate policies that mitigate the toxicity of aflatoxins in pregnant women, foetuses and newborns.

Aflatoxin B1 induces infertility, fetal deformities, and potential therapies

Aflatoxin B1 (AFB1) is a subsidiary poisonous metabolite, archetypally spawned by Aspergillus flavus and A. parasiticus, which are often isolated in warm or tropical countries across the world. AFB1 is capable of disrupting the functioning of several reproductive endocrine glands by interrupting the enzymes and their substrates that are liable for the synthesis of various hormones in both males and females. In men, AFB1 is capable of hindering testicular development, testicular degeneration, and reduces reproductive capabilities. In women, a direct antagonistic interaction of AFB1 with steroid hormone receptors influencing gonadal hormone production of estrogen and progesterone was responsible for AFB1-associated infertility. AFB1 is potentially teratogenic and is responsible for the development of malformation in humans and animals. Soft-tissue anomalies such as internal hydrocephalus, microphthalmia, cardiac defects, augmented liver lobes, reproductive changes, immune modifications, behavioral changes and predisposition of animals and humans to neoplasm development are AFB1-associated anomalies. Substances such as esculin, selenium, gynandra extract, vitamins C and E, oltipraz, and CDDO-Im are potential therapies for AFB1. Thus, this review elucidates the pivotal pathogenic roles of AFB1 in infertility, fetal deformities, and potential therapies because AFB1 toxicity is a key problem globally.

A Label-Free Aptasensor for Turn-On Fluorescent Detection of Aflatoxin B1 Based on an Aggregation-Induced-Emission-Active Probe and Single-Walled Carbon Nanohorns

The determination of the aflatoxin B1 (AFB1) content has received widespread attention in the context of food safety, which is a global public health issue. Accordingly, a label-free and turn-on fluorescent AFB1 determination method is developed herein with an ss-DNA aptamer as the recognition element, 4, 4-(1E,1E)-2, 2-(anthracene-9, 10-diyl) bis(ethene-2, 1-diyl) bis(N, N, N-trimethylbenzenaminium iodide) (DSAI) as the aggregation-induced emission (AIE) fluorescent probe, and single-walled carbon nanohorns (SWCNHs) as the selective part with a fluorescence quenching effect. In the presence of AFB1, the AFB1-specific aptamer undergoes a structural transformation and switches from being a random helix to a folded structure. DSAI's fluorescence is protected as a result of the resistance of the transformed aptamer adsorbed on the SWCNHs' surface. Because DSAI's fluorescence is not quenchable, the fluorescence intensity is calculated as a function of the AFB1 concentration. By simply mixing DSAI, aptamer, AFB1 samples, and SWCNHs, the method can be carried out in 2 h, with a limit of detection (LOD) of 1.83 ng/mL. It has a high selectivity in the presence of other mycotoxins, and its performance is confirmed in soybean sauce with a known concentration of AFB1. The LOD was 1.92 ng/mL in the soy sauce samples and the recovery ranged from 95 to 106%, implying that the presented aptasensor has great potential for food analysis.

A mixed methods assessment of knowledge, attitudes and practices related to aflatoxin contamination and exposure among caregivers of children under 5 years in western Kenya

OBJECTIVE

Identifying factors that may influence aflatoxin exposure in children under 5 years of age living in farming households in western Kenya.

DESIGN

We used a mixed methods design. The quantitative component entailed serial cross-sectional interviews in 250 farming households to examine crop processing and conservation practices, household food storage and consumption and local understandings of aflatoxins. Qualitative data collection included focus group discussions (N 7) and key informant interviews (N 13) to explore explanations of harvesting and post-harvesting techniques and perceptions of crop spoilage.

SETTING

The study was carried out in Asembo, a rural community where high rates of child stunting exist.

PARTICIPANTS

A total of 250 female primary caregivers of children under 5 years of age and thirteen experts in farming and food management participated.

RESULTS

Study results showed that from a young age, children routinely ate maize-based dishes. Economic constraints and changing environmental patterns guided the application of sub-optimal crop practices involving early harvest, poor drying, mixing spoiled with good cereals and storing cereals in polypropylene bags in confined quarters occupied by humans and livestock and raising risks of aflatoxin contamination. Most (80 %) smallholder farmers were unaware of aflatoxins and their harmful economic and health consequences.

CONCLUSIONS

Young children living in subsistence farming households may be at risk of exposure to aflatoxins and consequent ill health and stunting. Sustained efforts to increase awareness of the risks of aflatoxins and control measures among subsistence farmers could help to mitigate practices that raise exposure.

Presence, Co-Occurrence, and Daily Intake Estimates of Aflatoxins and Fumonisins in Maize Consumed in Food-Insecure Regions of Western Honduras

Foodborne mycotoxins are a significant food safety risk in developing countries. Our objective was to determine the occurrence of and exposure levels to aflatoxins (AFs) and fumonisins (FBs) in maize intended for human and animal consumption in food-insecure regions of western Honduras. Total AFs and FBs were quantified with a monoclonal antibody-based affinity spectrofluorimetric method. FBs were detected in 614/631 samples of maize destined for human consumption at 0.3 to 41 mg/kg (mean, 2.7 mg/kg). Of the 614 positive samples, 147 had FB levels exceeding the U.S. Food and Drug Administration (FDA) advisory threshold of 4.0 mg/kg. AFs were detected in 109/631 samples of maize for human consumption with concentrations between 1.0 and 490 µg/kg (mean, 10 µg/kg). AF levels in 34 samples exceeded the FDA regulatory limit (i.e., 20 µg/kg). The average probable daily intake of AFs in western Honduras ranged from 0 to 260 ng/kg body weight/day, and for FBs, the average probable daily intake ranged from 17 to 53 μg/kg body weight/day. AFs and FBs co-occurred in 106/631 samples with 60 samples containing both toxins at levels greater than the FDA regulatory levels. Samples of maize intended for animal feed had significantly higher AF (mean, 22 µg/kg) and FB (mean, 7.6 mg/kg) contamination levels than those observed in samples destined for human consumption. Thus, the maize supply chain in western Honduras is contaminated with mycotoxins at levels that pose health risks to both humans and livestock. More effective mycotoxin surveillance and implementation of effective mitigation strategies are needed to reduce mycotoxin contamination and exposure.

Construction of a nanoscale metal-organic framework aptasensor for fluorescence ratiometric sensing of AFB1 in real samples

Aflatoxins B1 (AFB1) that could contaminate agricultural products has received sustained attention due to its high toxicity and wide distribution. Therefore, sensitive and facile detection method for AFB1 is significant for food safety and control. In this work, a ratiometric fluorescence NMOFs-Aptasensor was developed based on the combination of Cy3-modified aptamer and zirconium-based nanoscale metal-organic frameworks (NMOFs). NMOFs served as energy donors, and Cy3 labeled on the AFB1 aptamer was used as an acceptor. An energy donor-acceptor pair was fabricated in the NMOFs-Aptasensor. With AFB1 selectively caught by the AFB1 aptamer, the fluorescence of the NMOFs-Aptasensor changed via fluorescence resonance energy transfer (FRET), and the fluorescence spectra changed accordingly. The ratiometric fluorescence signal was utilized to quantitatively measure AFB1. The reported NMOFs-Aptasensor presented great detection performance from 0 to 3.33 ng mL^-1, with an LOD of 0.08 ng mL^-1. Moreover, the fluorescence sensor was successfully applied to detect AFB1 in real samples.

Child Aflatoxin Exposure is Associated with Poor Child Growth Outcomes: A Prospective Cohort Study in Rural Malawi

Background

Aflatoxin (AF) exposure is associated with child growth faltering in cross-sectional studies, with limited findings from longitudinal studies.

Objectives

To evaluate the relationship between maternal AF B₁-lysine adduct concentration, child AF B₁-lysine adduct concentration, and child growth in the first 30 mo of life.

Methods

AF B₁-lysine adduct was measured in mother-child dyad plasma samples using isotope dilution mass spectrometry. Using linear regression, we assessed the relationship between AF B₁-lysine adduct concentration and child weight, height, and head and mid-upper arm circumferences at 1 wk, 6, 12, 18, 24, and 30 mo of age.

Results

In adjusted models, maternal prenatal AF B₁-lysine adduct (pg/μL) was positively associated with newborn anthropometric outcomes; largest beta coefficients for associations between standardized values were for newborn weight-for-age z-score [β = 0.13; 95% confidence interval (CI): 0.02, 0.24; P < 0.05 and β = 0.11; 95% CI: 0.00, 0.22; P < 0.05 for second and third trimester AF, respectively]. Child AF B₁-lysine adduct (pg/μL) at 6 mo was negatively associated with head circumference-for-age z-score at 6, 18, 24, and 30 mo, with beta coefficients ranging from β = -0.15; 95% CI: -0.28, -0.02 to β = -0.17; 95% CI: -0.31, -0.03; P < 0.05); 18-mo AF was negatively associated with anthropometric outcomes at 18, 24, and 30 mo, most consistently with length-for-age z-score (β = -0.18; 95% CI: -0.32, -0.04, β = -0.21; 95% CI: -0.35, -0.07, β = -0.18; 95% CI: -0.32, -0.03 at 18, 24 and 30 mo, respectively).

Conclusions

Child AF exposure was associated with impaired child growth, but maternal AF exposure was not. Exposure during infancy was linked to persistent deficit in head circumference, implying reduced brain size lasting beyond the age of 2 years. Exposure at 18 mo was linked to persistent linear growth deficit. Further research should elucidate mechanisms through which AF affects child growth.

A Novel Multicellular Placental Barrier Model to Investigate the Effect of Maternal Aflatoxin B1 Exposure on Fetal-Side Neural Stem Cells

Ingestion of food toxins such as aflatoxin B₁ (AFB₁) during pregnancy may impair fetal neurodevelopment. However, animal model results may not be accurate due to the species' differences, and testing on humans is ethically impermissible. Here, we developed an in vitro human maternal-fetal multicellular model composed of a human hepatic compartment, a bilayer placental barrier, and a human fetal central nervous system compartment using neural stem cells (NSCs) to investigate the effect of AFB₁ on fetal-side NSCs. AFB₁ passed through the HepG2 hepatocellular carcinoma cells to mimic the maternal metabolic effects. Importantly, even at the limited concentration (0.0641 ± 0.0046 μM) of AFB_1, close to the national safety level standard of China (GB-2761-2011), the mixture of AFB₁ crossing the placental barrier induced NSC apoptosis. The level of reactive oxygen species in NSCs was significantly elevated and the cell membrane was damaged, causing the release of intracellular lactate dehydrogenase (p < 0.05). The comet experiment and γ-H2AX immunofluorescence assay showed that AFB₁ caused significant DNA damage to NSCs (p < 0.05). This study provided a new model for the toxicological evaluation of the effect of food mycotoxin exposure during pregnancy on fetal neurodevelopment.

Aflatoxin Contamination, Exposure among Rural Smallholder Farming Tanzanian Mothers and Associations with Growth among Their Children

Recently, aflatoxin exposure especially through maize and groundnuts has been associated with growth impairment in children. Infants and children are considered to be more susceptible to toxins because of their lower body weight, higher metabolic rate, and lower ability to detoxify. On the other hand, for women of reproductive age, aflatoxin exposure may not only affect their health but also that of their foetus in the case of pregnancy. This study focused on investigating AFB1 contamination in maize and groundnut from respondent households, exposure among women of reproductive age and associations of aflatoxin contamination with growth retardation among children in Mtwara region, Tanzania. The highest maximum AFB1 contamination levels from all samples obtained were in maize grain (2351.5 μg/kg). From a total of 217 maize samples collected, aflatoxins were above European Union (EU) and East African Community (EAC) tolerable limits in 76.0% and 64.5% of all samples. Specifically, maize grain had the highest proportion of samples contaminated above tolerable limits (80.3% and 71.1% for EU and EAC limits). Groundnut had 54.0% and 37.9% of samples above EU and EAC maximum tolerable limits. The lowest proportion of contaminated samples on the other hand was for bambara nut (37.5% and 29.2% for EU and EAC limits, respectively). Aflatoxin exposure in our surveyed population was much higher than previous observations made in Tanzania and also higher than those observed in Western countries such as Australia and the USA. Among children, AFB1 concentration was associated with lower weight for height z scores and weight for age z scores in the univariate model (p < 0.05). In summary, these results indicate the seriousness of aflatoxin contamination in foods commonly consumed in the vulnerable population assessed. Strategies both from the health, trade, and nutrition sectors should therefore be designed and implemented to address aflatoxin and mycotoxin contamination in diets.

Mycotoxins were not associated with environmental enteropathy in a cohort of Tanzanian children

Enteropathy is a pathophysiological condition characterized by decreased intestinal barrier function and absorption. Past studies have hypothesized that mycotoxins might impair children's growth by causing intestinal enteropathy, including interactions between mycotoxins and pathogens. We investigated the association of two mycotoxins, aflatoxin B1 (AFB1 ) and fumonisin B1 (FB1 ), independently and in conjunction with microbial pathogens, with fecal biomarkers of environmental enteropathy in children. As part of a larger MAL-ED study, 196 children were recruited in Haydom, Tanzania, and followed for the first 36 months of life. The gut inflammation biomarkers myeloperoxidase (MPO), neopterin (NEO), and alpha-1-antitrypsin (A1AT) were analyzed in stool samples at 24 months; with mean concentrations 5332.5 ng/L MPO, 807.2 nmol/L NEO, and 0.18 mg/g A1AT. Forty-eight children were measured for AFB1 -lys, with a mean of 5.30 (95% CI: 3.93-6.66) pg/mg albumin; and 87 were measured for FB1 , with a mean of 1.25 (95% CI: 0.72-1.76) ng/ml urine. Although the pathogens adenovirus and Campylobacter were associated with A1AT (p = 0.049) and NEO (p = 0.004), respectively, no association was observed between aflatoxin (MPO, p = 0.30; NEO, p = 0.08; A1AT, p = 0.24) or fumonisin (MPO, p = 0.38; NEO, p = 0.65; A1AT, p = 0.20) exposure and any gut inflammation biomarkers; nor were interactive effects found between mycotoxins and pathogens in contributing to intestinal enteropathy in this cohort. Although further studies are needed to confirm these results, it is possible that mycotoxins contribute to child growth impairment via mechanisms other than disrupting children's intestinal function.

Mycoviruses in Fungi: Carcinogenesis of Fungal Agents May Not Always Be Mycotoxin Related

Certain viruses have been found to induce diverse biological pathways to carcinogenesis, evidenced by the presence of viral gene products in some tumors. Despite the fact that many fungal agents contain mycoviruses, until recently, their possible direct effects on human health, including carcinogenesis and leukemogenesis, had not been explored. In this regard, most studies of fungal agents have rightly concentrated on their mycotoxin formation and effects. Recently, the direct role of yeasts and fungi in the etiology of cancers, including leukemia, have been investigated. While greater attention has been placed on the carcinogenic effects of Candida, the role of filamentous fungi in carcinogenesis has also been explored. Recent findings from studies using the enzyme-linked immunosorbent assay (ELISA) technique indicate that the plasma of patients with acute lymphoblastic leukemia (ALL) uniformly contains antibodies for a certain mycovirus-containing Aspergillus flavus, while controls are negative. The exposure of mononuclear leukocytes from patients with ALL in full remission, and long-term survivors, to the product of this organism was reported to result in the re-development of typical genetics and cell surface phenotypes characteristic of active ALL. Mycoviruses are known to be able to significantly alter the biological characteristics and functions of their host. The possible carcinogenic and leukemogenic role of mycoviruses, with and without their host, needs to be further investigated.

Quantitative assessment of aflatoxin exposure and hepatocellular carcinoma (HCC) risk associated with consumption of select Nigerian staple foods

Aflatoxin contamination of staple grains and legumes has been linked to hepatocellular carcinoma (HCC) and other adverse health outcomes, constituting a substantial public health concern globally. Low-resource food environments in sub-Saharan Africa are often under-regulated and are particularly vulnerable to adverse health and nutrition outcomes associated with aflatoxin exposure. This study identifies levels of HCC risk in the northern Nigerian adult population, leveraging a systematic review of available evidence on aflatoxin contamination in Nigerian maize, groundnut, rice, cowpea, and soybean. Estimated dietary intake (EDI) was computed using publicly available dietary consumption data and a probabilistic quantitative risk assessment was conducted to determine the relative risk of HCC associated with consumption of selected aflatoxin-contaminated commodities. In total, 41 eligible studies reporting aflatoxin contamination were used to model the distribution of aflatoxin concentrations in Nigerian commodities. EDIs for maize, groundnut, rice, and cowpea exceeded the provisional maximum tolerable daily intake (PMTDI) level of 1 kgbw-1 day-1, with maize yielding the highest mean EDI (36.7 kgbw-1 day-1). The quantitative risk assessment estimated that 1.77, 0.44, 0.43, 0.15, and 0.01 HCC cases per year/100,000 population were attributable to aflatoxin exposure through maize, groundnut, rice, cowpea, and soybean, respectively. Sensitivity analysis revealed that aflatoxin concentration, dietary consumption levels, consumption frequency, and other variables have differing relative contributions to HCC risk across commodities. These findings constitute a novel multi-study risk assessment approach in the Nigerian context and substantiate existing evidence suggesting that there is reason for public health concern regarding aflatoxin exposure in the Nigerian population.

Structural insights into the AFB1 aptamer coupled with a rationally designed CRISPR/Cas12a-Exo III aptasensor for AFB1 detection

Aflatoxin B₁ (AFB₁) is a typical food contaminant. A truncated DNA aptamer of AFB₁ was reported by our team in previous work. However, the recognition mechanism between aptamer and AFB₁ was lacking, which was crucial for the design of related aptasensor. Herein, the binding of aptamer to AFB₁ was systematically studied and found that it was an exothermic process and the conformation of aptamer changed during the recognition process. Loop bases in the secondary structure of aptamer formed a special binding pocket to recognize AFB₁. Van der Waals and electrostatic interaction were the main driving forces. By blocking the stem bases guided by the structural investigation, a rationally designed CRISPR/Cas12a-Exo III aptasensor for AFB₁ detection was constructed, and the sensitivity was improved by target recycling. Under optimal conditions, the linear detection range for AFB₁ was 0.01-20 ng/mL, and AFB₁ was accurately determined in corn and wheat samples. This work laid a theoretical foundation for the design of AFB₁ aptasensor, and the developed detection model came up with new ideas for the development of CRISPR/Cas12a-based aptasensor.

Aflatoxins: Source, Detection, Clinical Features and Prevention

The most potent mycotoxin, aflatoxins are the secondary metabolite produced by fungi, especially Aspergillus, and have been found to be ubiquitous, contaminating cereals, crops, and even milk and causing major health and economic issues in some countries due to poor storage, substandard management, and lack of awareness. Different aspects of the toxin are reviewed here, including its structural biochemistry, occurrence, factors conducive to its contamination and intoxication and related clinical features, as well as suggested preventive and control strategies and detection methods.

Chronic aflatoxin exposure during pregnancy is associated with lower fetal growth trajectories: a prospective cohort from the Butajira Nutrition, Mental Health, and Pregnancy (BUNMAP) Study in rural Ethiopia

BACKGROUND

Aflatoxins are toxic secondary metabolites produced by Aspergillus fungi, which are ubiquitously present in the food supplies of low- and middle-income countries. Studies of maternal aflatoxin exposure and fetal outcomes are mainly focused on size at birth and the effect on intrauterine fetal growth has not been assessed.

OBJECTIVES

In the present study, we examined the association between chronic aflatoxin exposure during pregnancy and fetal growth trajectories in a rural setting in Ethiopia.

METHODS

In a prospective cohort study, we enrolled 492 pregnant females, with a singleton pregnancy and before 28 wk of gestation. Serum aflatoxin B1-lysine concentration was measured using LC-tandem MS. Three rounds of ultrasound measurements were conducted to estimate fetal weight at mean ± SD gestational age weeks of 19.1 ± 3.71, 28.5 ± 3.51, and 34.5 ± 2.44. Estimated fetal weight was expressed in centiles using the International Fetal and Newborn Growth Consortium for the 21st Century (INTERGROWTH-21st) reference. We fitted a multivariable linear mixed-effects model to estimate the rate of fetal growth between aflatoxin-exposed (i.e., aflatoxin B1-lysine concentration above or equal to the limit of detection) and unexposed mothers in the study.

RESULTS

Mothers had a mean ± SD age of 26.0 ± 4.58 y. The median (25th, 75th percentile) serum aflatoxin B1-lysine concentration was 12.6 (0.93, 96.9) pg/mg albumin, and aflatoxin exposure was observed in 86.6% of maternal blood samples. Eighty-five percent of the females enrolled provided at least 2 ultrasound measurements for analysis. On average, the aflatoxin-exposed group had a significantly lower change over time in fetal weight-for-gestational-age centile than the unexposed group (ß = -0.92; 95% CI: -1.77, -0.06 centiles/week; P = 0.037).

CONCLUSIONS

Chronic maternal aflatoxin exposure is associated with lower fetal growth over time. Our findings emphasize the importance of nutrition-sensitive strategies to mitigate dietary aflatoxin exposure and adopting food safety measures in low-income settings, in particular during the fetal period of development.

Human Breast Milk Contamination with Aflatoxins, Impact on Children's Health, and Possible Control Means: A Review

Aflatoxins are natural toxicants produced mainly by species of the Aspergillus genus, which contaminate virtually all feeds and foods. Apart from their deleterious health effects on humans and animals, they can be secreted unmodified or carried over into the milk of lactating females, thereby posing health risks to suckling babies. Aflatoxin M1 (AFM1) is the major and most toxic aflatoxin type after aflatoxin B1 (AFB1). It contaminates human breast milk upon direct ingestion from dairy products or by carry-over from the parent molecule (AFB1), which is hydroxylated in the liver and possibly in the mammary glands by cytochrome oxidase enzymes and then excreted into breast milk as AFM1 during lactation via the mammary alveolar epithelial cells. This puts suckling infants and children fed on this milk at a high risk, especially that their detoxifying activities are still weak at this age essentially due to immature liver as the main organ responsible for the detoxification of xenobiotics. The occurrence of AFM1 at toxic levels in human breast milk and associated health conditions in nursing children is well documented, with developing countries being the most affected. Different studies have demonstrated that contamination of human breast milk with AFM1 represents a real public health issue, which should be promptly and properly addressed to reduce its incidence. To this end, different actions have been suggested, including a wider and proper implementation of regulatory measures, not only for breast milk but also for foods and feeds as the upstream sources for breast milk contamination with AFM1. The promotion of awareness of lactating mothers through the organization of training sessions and mass media disclosures before and after parturition is of a paramount importance for the success of any action. This is especially relevant that there are no possible control measures to ensure compliance of lactating mothers to specific regulatory measures, which can yet be appropriate for the expansion of breast milk banks in industrialized countries and emergence of breast milk sellers. This review attempted to revisit the public health issues raised by mother milk contamination with AFM1, which remains undermined despite the numerous relevant publications highlighting the needs to tackle its incidence as a protective measure for the children physical and mental health.

Chronic Aflatoxin Exposure and Cognitive and Language Development in Young Children of Bangladesh: A Longitudinal Study

Aflatoxin can cross the blood-brain barrier, damage brain tissues, and have the potential to harm the development of the human brain. Although dietary aflatoxin exposure is common in children, there is a paucity of data on aflatoxin exposure and child developmental outcomes. The child's cognitive, motor, and language functions were assessed using the Bayley Scales of Infant and Toddler Development-III or BSID-III at the same time points. Association between exposure to aflatoxin and subtests of BSID-III were examined using mixed-effect linear regression. Aflatoxin assays were performed on 194, 167, and 163 children at 15, 24, and 36 months of age, and chronic aflatoxin exposure was detected in 20.6%, 16.8%, and 60.7% of children, respectively. Multi-variable analyses showed that aflatoxin exposure was independently related to the children's cognitive score (β: -0.69; 95% CI: -1.36, -0.02), receptive language score (β: -0.90; 95% CI: -1.62, -0.17), and expressive language score (β: -1.01; 95% CI: -1.96, -0.05). We did not observe any association between exposure to aflatoxin and the motor function of children. Chronic exposure to aflatoxin exposure was linked to reduced cognitive, expressive, and receptive language scores of the study children. Further research is needed in a different setting to confirm this novel finding.

Assessing an aflatoxin exposure biomarker: Exploring the interchangeability and correlation between venous and capillary blood samples

Exposure to dietary aflatoxins has been recognized as a potential threat to child nutrition and growth, in addition to being a known carcinogen. The ability to accurately assess concentration of aflatoxin in the blood of at-risk individuals is therefore very important to inform public health policies and on-the-ground programs around the world. Venous blood is frequently used to quantify biomarkers of exposure such as AFB1-lysine adducts. However, venous blood collection methods are invasive, requiring highly trained staff, which makes this method challenging to implement, especially in resource-limited settings. In contrast, capillary blood collection by fingerprick is less invasive and has the potential for application in point-of-need monitoring. The aim of this exploratory study was to investigate the correlation and interchangeability of capillary and venous human blood samples in the quantification of AFB1-lysine adduct concentration. A total of 72 venous and capillary blood samples were collected from 36 women of reproductive age (16-49 years) in northern Uganda. All sample specimens were analyzed using high-performance liquid chromatography with fluorescence detection. Regression analysis and Bland-Altman analysis were performed to compare AFB1-lysine concentrations between venous and capillary sample pairs. Bland-Altman analysis of albumin-normalized AFB1-lysine data-bias was -0.023 pg/mg-albumin and the 95% limits of agreement were 0.51 to -0.56 pg/mg-albumin for log-transformed data. There was a positive correlation between albumin-normalized venous and capillary AFB1-lysine concentrations with r of 0.71 (p < .0001). A lack of any accepted clinical cutoff for aflatoxin exposure makes definition of an 'acceptable' limit for statistical analysis and comparison of methods challenging. Our data suggests a positive correlation between albumin-normalized AFB1-lysine concentrations in venous and capillary sample pairs, but relatively weak agreement and interchangeability based on Bland-Altman analysis.

Safety Assessment of Locusta migratoria Powder Enriched Peanut-Based Ready-to-Use Therapeutic Foods (RUTF)

Migratory locust has been widely reported as a quality protein source. However, there are food safety problems related with the usage of insects as food. In this study, migratory locust powder (MLP) was used as a protein supply alternative to milk powder (MP) in peanut-based RUTFs. Seven formulations were obtained at different substitution levels (0 – 30%) of MP with MLP. Pesticide residues, aflatoxins, triazine and toxic metals were analysed using a GC-MS system and Atomic Absorption Spectrophotometer. Formulation with 30% MLP and without milk have the highest level of organochlorine (3.22 µg/kg), organophosphorus (0.40-4.56µg/kg) amongst others. Aflatoxins of the therapeutic foods increased with increasing levels of MLP. The heavy metals, melamine, and cyanuric acid of the RUTFs were below the standard permissible limits. Migratory locust powder could be used as an alternate protein source in the formulation of peanut based RUTFs without posing health threat.

An Eight-Year Survey on Aflatoxin B1 Indicates High Feed Safety in Animal Feed and Forages in Northern Italy

Aflatoxins (AFs) remain the main concern for the agricultural and dairy industries due to their effects on the performances and quality of livestock production. Aflatoxins are always unavoidable and should be monitored. The objective of this paper is to bring to light a significant volume of data on AF contamination in several animal feed ingredients in Northern Italy. The Regional Breeders Association of Lombardy has been conducting a survey program to monitor mycotoxin contamination in animal feeds, and in this paper, we present data relating to AFB1 contamination. In most cases (95%), the concentrations were low enough to ensure compliance with the European Union's (EU's) maximum admitted levels for animal feed ingredients. However, the data show a high variability in AF contamination between different matrices and, within the same matrix, a high variability year over year. High levels of AFs were detected in maize and cotton, especially in the central part of the second decade of this century, i.e., 2015-2018, which has shown a higher risk of AF contamination in feed materials in Northern Italy. Variability due to climate change and the international commodity market affect future prospects to predict the presence of AFs. Supplier monitoring and control and reduced buying of contaminated raw materials, as well as performing analyses of each batch, help reduce AF spread.

May phytophenolics alleviate aflatoxins-induced health challenges? A holistic insight on current landscape and future prospects

The future GCC-connected environmental risk factors expedited the progression of nCDs. Indeed, the emergence of AFs is becoming a global food security concern. AFs are lethal carcinogenic mycotoxins, causing damage to the liver, kidney, and gastrointestinal organs. Long-term exposure to AFs leads to liver cancer. Almost a variety of food commodities, crops, spices, herbaceous materials, nuts, and processed foods can be contaminated with AFs. In this regard, the primary sections of this review aim to cover influencing factors in the occurrence of AFs, the role of AFs in progression of nCDs, links between GCC/nCDs and exposure to AFs, frequency of AFs-based academic investigations, and world distribution of AFs. Next, the current trends in the application of PPs to alleviate AFs toxicity are discussed. Nearly, more than 20,000 published records indexed in scientific databases have been screened to find recent trends on AFs and application of PPs in AFs therapy. Accordingly, shifts in world climate, improper infrastructures for production/storage of food commodities, inconsistency of global polices on AFs permissible concentration in food/feed, and lack of the public awareness are accounting for a considerable proportion of AFs damages. AFs exhibited their toxic effects by triggering the progression of inflammation and oxidative/nitrosative stress, in turn, leading to the onset of nCDs. PPs could decrease AFs-associated oxidative stress, genotoxic, mutagenic, and carcinogenic effects by improving cellular antioxidant balance, regulation of signaling pathways, alleviating inflammatory responses, and modification of gene expression profile in a dose/time-reliant fashion. The administration of PPs alone displayed lower biological properties compared to co-treatment of these metabolites with AFs. This issue might highlight the therapeutic application of PPs than their preventative content. Flavonoids such as quercetin and oxidized tea phenolics, curcumin and resveratrol were the most studied anti-AFs PPs. Our literature review clearly disclosed that considering PPs in antioxidant therapies to alleviate complications of AFs requires improvement in their bioavailability, pharmacokinetics, tissue clearance, and off-target mode of action. Due to the emergencies in the elimination of AFs in food/feedstuffs, further large-scale clinical assessment of PPs to decrease the consequences of AFs is highly required.

Modulatory Effects of Arctostaphylos uva-urs Extract In Ovo Injected into Broiler Embryos Contaminated by Aflatoxin B1

In ovo injection of nutrients can modulate the embryo’s physiological responses against aflatoxin B1 (AFB1) embryotoxicity. This hypothesis was tested using in ovo injection of Arctostaphylos uva-ursi (Ar. uu.) methanolic extract. The total polyphenols, total flavonoids, total antioxidant capacity, and GC-MS analysis were all assessed in the Ar. uu. methanolic extract. A total of 180 ten-day-old embryonated eggs were distributed into six groups of 30 replicates each. The first group was used as a control (non-injected), and the second, third, fourth, fifth, and sixth groups were injected with 10 µ double-distilled water (DDW), 500 µL methanol, 0.01 g Ar. uu./500 µL methanol, 50 ng AFB1/10 µL DDW, and 50 ng AFB1 in 10 µ DDW + 0.01 g Ar. uu./500 µL methanol, respectively. The relative embryo weight, residual yolk sac weight, tibia length and weight, and survival were recorded. Total and differential leukocytes, oxidative stress, and humoral immune responses were observed. The residual yolk sac was lower (p < 0.05) in the Ar. uu. group than other groups. The embryonic growth (tibia weight and length) was enhanced in AFB1 + Ar. uu.-injected embryos compared with those injected with AFB1 alone. In conclusion, in ovo injection of Arctostaphylos uva-ursi could modulate AFB1-induced toxicity in chicken embryos.

Aflatoxin M1 exposure in a fermented millet-based milk beverage 'brukina' and its cancer risk characterization in Greater Accra, Ghana

Brukina is a millet based fermented milk product which is consumed as a beverage in Ghana. It is however prone to aflatoxin M1 (AFM1) contamination, which is a serious health challenge for low and middle-income countries in subtropical regions. This study aimed at evaluating AFM1 levels and cancer risks associated with brukina (n = 150) sampled from different locations of the Greater Accra Region of Ghana. AFM1 were measured with High-Performance Liquid Chromatography (HPLC) connected to a Fluorescence Detector (FLD).Cancer risk assessments were also conducted using models prescribed by the Joint FAO/WHO Expert Committee on Additives (JECFA). Out of the 150 samples analyzed for AFM1, 80/150 (53%) tested positive between the range 0.00 ± 0.001-3.14 ± 0.77 µg/kg. Cancer risk assessments of AFM1 produced outcomes which ranged between 0.64 and 1.88 ng/kg bw/day, 0.31-9.40, 0.0323, and 1.94 × 10-3-0.06 for cases/100,000 person/yr for Estimated Daily Intake (EDI), Hazard Index (H.I), Average Potency, and Cancer Risks respectively for all age categories investigated. It was concluded that the consumption of brukina posed adverse health effects on the majority of the age categories in the different locations of Greater Accra Region since the calculated H.Is were greater than one (> 1). Therefore, contamination of brukina with AFM1 should be considered a high priority in public health and Ghana's cancer risk management actions.

Antagonism of Cyanamide-3-O-glucoside and protocatechuic acid on Aflatoxin B1-induced toxicity in zebrafish larva (Danio rerio)

The zebrafish model was used to evaluate the antioxidant properties of cyanidin-3-O-glucoside (C₃G) and its metabolite protocatechuic acid (PCA) against aflatoxin B₁ (AFB₁)-induced hepatotoxicity and oxidative stress. In this study, zebrafish larvae were cultured for 3 days post fertilization (dpf) and then induced with AFB₁. After induced 4 h, 8 h, 12 h, and 24 h, 5 μg/mL C₃G/PCA was added and then co-cultured to 5 dpf, respectively. The experiments showed that C₃G/PCA suppressed AFB₁-induced zebrafish liver atrophy and delayed the absorption of the yolk sac. In addition, reactive oxygen species (ROS) and cell death were also significantly decreased by 5 μg/mL C₃G/PCA (P ˂ 0.05). C₃G/PCA significantly reduced hepatic biomarkers in the serum contents (P ˂ 0.05). Besides, glutathione (GSH) contents were significantly upregulated, and the activities of superoxide dismutase (SOD) and catalase (CAT) were significantly elevated in zebrafish (P ˂ 0.05). The addition of 5 μg/mL C₃G/PCA was capable of reducing the apoptotic levels of caspase-9 and caspase-3 after 100 ng/mL AFB₁ intoxication. In conclusion, these results suggested that C₃G and its metabolite PCA might antagonize the hepatotoxicity of AFB₁, reduce oxidative damage and inhibit cell death.

Pathological effects of graded doses of aflatoxin B1 on the development of the testes in juvenile white leghorn males

Current experiment was planned to investigate the deleterious effects of the graded doses of aflatoxin B1 (AFB1) on white leghorn male birds. For this purpose, one-hundred birds of 8 weeks of age were divided into 4 equal groups and reared on feed contaminated with different doses of AFB1 for 10 weeks. Group A was kept as a control group and was fed with normal toxin-free diet; groups B, C, and D were offered feed containing 100 ppb, 200 ppb, and 400 ppb of AFB1, respectively. The birds were euthanized at the 4th and 10th week of the experiment. Clinical signs, behavioral changes, absolute and relative organ weight of the testes, and sperm motility were measured. Cellular immune response was observed through carbon clearance assay (CCA), P-HAP, and antibody response against sheep red blood cells (SRBC). Results showed a dose-dependent decline in the immune response of birds with the increase in the level of AFB1 in the feed. A significant decrease in the serum levels of testosterone, prolactin, and LH were observed at the end of the study. Grossly, testicular size and volume were reduced in ABF1 fed birds, while histological examination showed moderate to severe necrosis of testicular parenchyma, with partial to complete arrest of spermatogenesis. Very few spermatozoa were found in group C, while they were almost absent in group D which was offered a diet containing 400 ppb AFB1. The motility of sperms was reduced in all treated groups except control. The abovementioned results showed that AFB1 had severe toxic effects on the reproductive and immunological parameters of WLH male birds in a dose-dependent manner.

Urinary Aflatoxin M1 Concentration and Its Determinants in School-Age Children in Southern Ethiopia

Aflatoxins are mycotoxins that can contaminate grains, legumes, and oil seeds. These toxic compounds are an especially serious problem in tropical and sub-tropical climates. The objective of this study was to raise awareness of aflatoxin exposure among primary school children in Shebedino woreda, southern Ethiopia, by measuring urinary aflatoxin M1 (AFM1). The study employed a cross-sectional design and systematic random sampling of children from eight schools in the district. The mean ± SD age of the children was 9.0 ± 1.8 years. Most (84.6%) households were food insecure with 17.9% severely food insecure. Urinary AFM1 was detected in more than 93% of the children. The median [IQR] concentration of AFM1/Creat was 480 [203, 1085] pg/mg. Based on a multiple regression analysis: DDS, consumption of haricot bean or milk, source of drinking water, maternal education, and household food insecurity access scale scores were significantly associated with urinary AFM1/Creat. In conclusion, a high prevalence of urinary AFM1 was observed in this study. However, the relation between AFM1 and dietary intake was analyzed based on self-reported dietary data; hence, all of the staple foods as well as animal feeds in the study area should be assessed for aflatoxin contamination.

Assessment of aflatoxin B1-lysine adduct in children and its effect on child growth in Lahore, Pakistan

Aflatoxin B₁ is an important toxic food contaminant and there is very little information available about its exposure and effects on the health of the Pakistani population. Therefore, children (n = 238) aged 1-11 years were recruited in this study to estimate the levels of aflatoxin B₁-lysine adduct and to measure its adverse effects on growth. Blood samples were analyzed to detect AFB₁-lysine adducts through high-performance liquid chromatography. Socio-demographic information and anthropometry measurements were also obtained. All participants had detectable levels of AFB₁-lysine adduct with a median concentration of 10.66 pg/mg albumin (95% CI: 8.6-12.4). Differences in area of residence (p < 0.05) and the father's employment (p < 0.05) were significant predictors for aflatoxin concentration levels in ordinary least square and quantile regression models (residence in 75th quantile and father employment in 90th quantile). Children aged from 5 to 11 years in the 5th and 90th quantiles of the regression model had a significant association with aflatoxin levels. A very high (50.4%, 120/238) prevalence of growth impairment (stunting, wasting, and underweight) was also observed in this study. Although we couldn't establish the effect of aflatoxin on growth impairment, children with low serum albumin levels (OR = 0.18; 95% CI: 0.05-0.56; p = 0.004) were likely to be at risk of wasting. Also, low birth weight was strongly associated with wasting (OR = 3.11; 95% CI: 1.36-7.03; p = 0.006) and underweight (OR = 4.60; 95% CI: 2.21-10.05; p= <0.001), while the mother's school level education had a correlation with child stunting (OR = 1.84; 95% CI: 1.07-3.22; p = 0.029). The high prevalence of growth impairment and high concentration of serum AFB₁-lysine adduct levels in study participants demand immediate efforts to mitigate the adverse health outcomes in children in Pakistan.

Validation of a HACCP community-based infants' complementary food safety assurance method in cash crop producing communities in Gedeo zone, Southern Ethiopia

A method based on a hazard analysis critical control point (HACCP)-based standard operating procedure (SOP) has been developed and implemented in community-based (CB) production of complementary foods (CFs) in agrarian regions in rural Ethiopia. The objective of this study was to validate the method in another setup, more specifically in cash crop (coffee and khat) producing communities in Southern Ethiopia. A quasi-experimental study was employed for the method validation. Two villages in the Gedeo zone, Southern Ethiopia were selected and a total of 40 mother-child pairs, 20 in each village, were involved in the study. Sociodemographic data, knowledge, and complementary feeding practices were collected using pretested questionnaires. The training was given to each mother for 1 h about community-based CFs production and implementation of the method. Then, 30 CF samples were collected and the level of aflatoxins (AFB1, AFB2, AFG1, and AFG2) was determined using a validated method. The majority (77.5%) of the mothers understand the importance of complementary feeding and give it to their infants beyond 6 months. Nearly two-thirds (62.5%) of the mothers had knowledge about the health impacts of aflatoxins, but the remaining 37.5% lacked awareness about the health risks of aflatoxins. Mothers were very well-motivated for the training and they promised to implement the knowledge and skill gained from the training for improving the nutritional status of their children. Overall, 23.3% of the CFs were contaminated by aflatoxins. AFB1 and AFG1 were detected in 6.7 and 16.7% of the CF samples, respectively. In cash crop-producing communities around the country, the HACCP-based SOP is easily validated in CB CFs production. Therefore, a scaleup of the method at the national level and beyond is recommended.

Occurrence and exposure assessment of aflatoxins in Zhejiang province, China

The purpose of this study was to assess the risk of aflatoxins due to multiple food consumption among the Zhejiang population. Ultra-high-performance liquid chromatography coupled with tandem mass spectrometry method was used to determine aflatoxins in 792 samples. Aflatoxins were detected in 27.1% of the samples at levels between 0.07 and 262.63 μg kg^-1, and aflatoxins B₁ was the most frequently detected among different types of samples. 0.8% of peanut oil, 3.39% of nut products as well as 1.1% of condiments contaminated with aflatoxins B₁ exceeded China national tolerance limits. Peanut oil had the highest incidence of aflatoxin, with a range from 0.17 to 22.50 μg kg^-1. Using bags conferred limited advantages in reducing aflatoxin contents. Moreover, peanut and rice were the main contributors to dietary exposure to aflatoxins among Zhejiang residents. Finally, the margin of exposure values obtained by rice consumption were far from the safe margin of 10,000, indicating a potential risk to public health. The results pointed out the need for further prioritization of aflatoxins B₁ risk-management actions in Zhejiang.

PINK1/Parkin-mediated mitophagy as a protective mechanism against AFB1-induced liver injury in mice

Aflatoxin B₁ (AFB₁) can cause oxidative stress leading to mitochondrial damage and subsequent liver injury. Although it is well-known that damaged mitochondria are eliminated by PINK1/Parkin-mediated mitophagy, this mechanism has not yet been characterized in the context of AFB₁-induced liver injury. In this study, male wild-type C57BL/6N mice were divided into groups 1-4, which were then orally administered 0, 0.5, 0.75, and 1 mg/kg body weight AFB₁ for 28 d, respectively. Our results demonstrated that oxidative stress, NLRP3-inflammasome activation, and mitochondrial damage were dose-dependently augmented in AFB₁-induced liver injury. Additionally, PINK1/Parkin-mediated mitophagy peaked in the groups that had received a mid-dose of AFB₁ (0.75 mg/kg), which was attenuated slightly in high-dose groups. Afterward, we further characterized AFB₁-induced liver injury by comparing wild-type C57BL/6N mice with Parkin knockout (Parkin^-/-) mice. We found that the restricted mitophagy in Parkin^-/- mice was associated with increased oxidative stress, NLRP3-inflammasome activation, mitochondrial damage, and liver injury. Taken together, these results indicate that PINK1/Parkin-mediated mitophagy plays an important role in attenuating AFB₁-induced liver injury in mice.

Aflatoxin B1 Metabolism of Reared Alphitobius diaperinus in Different Life-Stages

The presence of carcinogenic aflatoxins in food and feed is a major issue. In prior studies, aflatoxin B1 (AfB1) and known primary metabolites were absent from Lesser Mealworm (LMW, Alphitobius diaperinus) reared on contaminated diets. LMW is a promising alternative protein source. The objectives of this stu\dy were to determine whether LMW can be reared on AfB1-contaminated feed in each life-stage, and to gather more insight into potential metabolites formed. Results suggested no adverse effects in terms of survival/growth when three stages of LMW (larvae, pre-pupae, beetles) were exposed to feed containing AfB1 concentrations of 200 and 600 µg/kg for 48 h. Insect and frass samples were analyzed by LC-MS/MS and high-resolution MS to, respectively, quantify concentrations of AfB1 and its major metabolites, and determine secondary metabolites. No AfB1 or major metabolites were quantified in the insect samples. Mass balance calculations showed that up to 40% of spiked AfB1 could be recovered in the frass, in the form of AfB1, aflatoxicol and AfM1. HRMS results suggested the presence of additional metabolites in the frass, but, due to lack of commercially available reference standards for these compounds, exact identification and quantification was not possible. More research is needed to verify the absence of toxicity.

Understanding drivers of stunting reduction in Nigeria from 2003 to 2018: a regression analysis

Nigeria is a high burden country for stunting. Stunting reduction has been slow and characterized by unequal progress across the 36 states and federal capital territory of the country. This study aimed to assess the changes in prevalence of stunting and growth determinants from 2003 to 2018, identify factors that predicted the change in stunting, and project future stunting prevalence if these predicted determinants improve. Trend and linear decomposition analyses of growth outcomes and determinants were conducted using 2003, 2008, 2013, and 2018 Nigeria Demographic and Health Survey data. Pooled data included 57,507 children 0 to 59 months old. Findings show that stunting and severe stunting significantly reduced from 43 to 37% and 23% to 17%, respectively (p < 0.001), between 2003 and 2018. Disturbingly, height-for-age z-scores at birth significantly decreased, indicating risks of potential future stunting increase. Improvements in nine stunting determinants (maternal body mass index, maternal height, ≥ 4 antenatal care visits, health facility delivery, reduced child illnesses, asset index, maternal education, paternal education, and preceding birth interval) predicted stunting reductions in children 0–59 months. Few of these nine determinants improved in subpopulations with limited stunting progress. Intra-sectoral and multisectoral coordination were potentially inadequate; 12% of children had received all of three selected health sector interventions along a continuum of care and 6% had received all of six selected multisector interventions. Forward looking projections suggest that increased efforts to improve the nine predictors of stunting change can reduce under-five stunting in Nigeria to ≤ 27% in the short term.

Estimation of Tolerable Daily Intake (TDI) for Immunological Effects of Aflatoxin

Aflatoxins are toxic chemicals produced by the fungi Aspergillus flavus and Aspergillus parasiticus. In warm climates, these fungi frequently contaminate crops such as maize, peanuts, tree nuts, and sunflower seeds. In many tropical and subtropical regions of the world, populations are coexposed to dietary aflatoxin and multiple infectious pathogens in food, water, and the environment. There is increasing evidence that aflatoxin compromises the immune system, which could increase infectious disease risk in vulnerable populations. Our aim was to conduct a dose-response assessment on a noncarcinogenic endpoint of aflatoxin: immunotoxicological effects. We sought to determine a noncarcinogenic tolerable daily intake (TDI) of aflatoxin, based on the existing data surrounding aflatoxin and biomarkers of immune suppression. To conduct the dose response assessment, mammalian studies were assessed for appropriateness of doses (relevant to potential human exposures) as well as goodness of data, and two appropriate mouse studies that examined decreases in leukocyte counts were selected to generate dose response curves. From these, we determined benchmark dose lower confidence limits (BMDL) as points of departure to estimate a range of TDIs for aflatoxin-related immune impairment: 0.017-0.082 μg/kg bw/day. As aflatoxin is a genotoxic carcinogen, and regulations concerning its presence in food have largely focused on its carcinogenic effects, international risk assessment bodies such as the Joint Expert Committee on Food Additives (JECFA) have never established a TDI for aflatoxin. Our work highlights the importance of the noncarcinogenic effects of aflatoxin that may have broader public health impacts, to inform regulatory standard-setting.

Longitudinal Assessment of Prenatal, Perinatal, and Early-Life Aflatoxin B1 Exposure in 828 Mother-Child Dyads from Bangladesh and Malawi

BACKGROUND

In utero or early-life exposure to aflatoxin, which contaminates staple crops in disadvantaged settings, may compromise pregnancy and infant outcomes, but investigations into the extent, persistence, and determinants of aflatoxin exposure at these life stages have lacked longitudinal data collection and broad geographic representation.

OBJECTIVES

Aflatoxin exposure and selected determinants thereof were characterized in mother-child dyads with serial plasma/serum samples in prenatal, perinatal, and early life in Malawi and Bangladesh.

METHODS

Circulating aflatoxin B1 (AFB1)-lysine albumin adducts were measured in dyads from Bangladesh (n = 573; maternal first and third trimester, 3 mo postpartum, cord blood, infant 24 mo) and Malawi (n = 255; maternal second and third trimester, 6 mo postpartum, infant 6 and 18 mo) with isotope dilution mass spectrometry. We examined AFB1-lysine adduct magnitude, persistence, seasonality, and associations with infant feeding, and estimated daily AFB1 intake.

RESULTS

Maternal AFB1-lysine was higher in Malawi (98% detectable; median: 0.469, IQR: 0.225-1.027 pg/µL) than in Bangladesh (59%; 0.030, nondetectable [nd]-0.077 pg/µL). Although estimated dietary exposure in Malawi was temporally stable (648 ng AFB1/day), estimated intake in Bangladesh was reduced by 94% between rainy and winter seasons (98 to 6 ng/day). AFB1-lysine was low in cord blood from Bangladesh (15% detectable; 0.045, 0.031-0.088 pg/µL among detectable) and in Malawian infants at 6 mo of age (0.072, nd-0.236 pg/µL), but reached maternal concentrations by 18 or 24 mo (Bangladesh: 0.034, nd-0.063 pg/µL; Malawi: 0.370, 0.195-0.964 pg/µL). In Malawian infants, exclusive breastfeeding at 3 mo was associated with 58% lower AFB1-lysine concentrations at 6 mo compared with other feeding modes (P = 0.010).

CONCLUSIONS

Among pregnant women, aflatoxin exposure was persistently high in Malawi, while lower and seasonal in Bangladesh. Infants were partially protected from exposure in utero and with exclusive breastfeeding, but exposures reached adult levels by 18-24 mo of age. The Bangladesh and Malawi trials are registered at clinicaltrials.gov as NCT00860470 and NCT01239693.

Bayesian geostatistical modelling of stunting in Rwanda: risk factors and spatially explicit residual stunting burden

Background

Stunting remains a significant public health issue in Rwanda and its prevalence exhibits considerable geographical variation. We apply Bayesian geostatistical modelling to study the spatial pattern of stunting in children less than five years considering anthropometric, socioeconomic and demographic risk factors in Rwanda. In addition, we predict the spatial residuals effects to quantify the burden of stunting not accounted for by our geostatistical model.

Methods

We used the data from the 2015 Rwanda Demographic and Health Survey. We fitted two spatial logistic models with similar structures, only differentiated by the inclusion or exclusion of spatially structured random effects.

Results

The risk factors of stunting identified in the geostatistical model were being male (OR = 1.32, 95% CI: 1.16, 1.47), lower birthweight (kg) (OR = 0.96, 95% CI: 0.95, 0.97), non-exclusive breastfeeding (OR = 1.24, 95% CI: 1.04, 1.45), occurrence of diarrhoea in the last two weeks (OR = 1.18, 95% CI: 1.02, 1.37), a lower proportion of mothers with overweight (BMI ≥ 25) (OR = 0.82, 95% CI: 0.71, 0.95), a higher proportion of mothers with no or only primary education (OR = 1.14, 95% CI: 0.99, 1.36). Also, a higher probability of living in a house with poor flooring material (OR = 1.22, 95% CI: 1.06, 1.41), reliance on a non-improved water source (OR = 1.13, 95% CI: 1.00, 1.27), and a low wealth index were identified as risk factors of stunting. Mapping of the spatial residuals effects showed that, in particular, the Northern and Western regions, followed by the Southern region of Rwanda, still exhibit a higher risk of stunting even after accounting for all the covariates in the spatial model.

Conclusions

Further studies are needed to identify the still unknown spatially explicit factors associated with higher risk of stunting. Finally, given the spatial heterogeneity of stunting, interventions to reduce stunting should be geographically targeted.

Associations between aflatoxin B 1 ‐albumin adduct levels with metabolic conditions in Guatemala: A cross‐sectional study

Background and Aims

Metabolic conditions such as obesity, type 2 diabetes, metabolic syndrome, and nonalcoholic fatty liver disease (NAFLD) are highly prevalent in Guatemala and increase the risk for a number of disorders, including hepatocellular carcinoma (HCC). Aflatoxin B₁ (AFB₁) levels are also notably elevated in the population and are known to be associated with HCC risk. Whether AFB₁ also contributes to the high prevalence of the metabolic disorders has not been previously examined. Therefore, the purpose of this study was to assess the association between AFB₁ and the metabolic conditions.

Methods

Four‐hundred twenty‐three individuals were included in the study, in which AFB₁‐albumin adduct levels were measured in sera. Metabolic conditions included diabetes, obesity, central obesity, metabolic syndrome, and NAFLD. Crude and adjusted prevalence odds ratios (PORs) and 95% confidence intervals (95% CI) were estimated for the associations between the metabolic conditions and AFB₁‐albumin adduct levels categorized into quartiles.

Results

The study found a significant association between AFB₁‐albumin adduct levels and diabetes (Q4 vs Q1 POR = 3.74, 95%CI: 1.71‐8.19; P‐trend .003). No associations were observed between AFB₁‐albumin adduct levels and the other conditions.

Conclusions

As diabetes is the metabolic condition most consistently linked to HCC, the possible association between AFB₁ exposure and diabetes may be of public health importance. Further studies are warranted to replicate the findings and examine potential mechanisms.

Recent progress in fluorescent aptasensors for the detection of aflatoxin B1 in food

Aflatoxin B1 pollution is one of the most critical issues of food safety and has been categorized as a group I carcinogen by the International Agency for Research on Cancer. Aflatoxin B1 exists in various foods and feedstuff products and can be produced and contaminate food products in all processes, including growth, harvest, storage, or processing. Therefore, it is of great value for detecting and on-site monitoring aflatoxin B1. Aptamers are short single-stranded DNA or RNA obtained from the nucleic acid molecular library through SELEX. With advantages of high specificity, large affinity, and easy modification, aptasensors have become popular in a wide range of promising applications. This review focuses on recent advances on fluorescent aptamer sensors for the detection of aflatoxin B1, including their design strategies, working mechanisms, and applications to on-site detection. Finally, the current challenges and prospects are discussed.

Recent advances in nanomaterials integrated immunosensors for food toxin detection

For the management and prevention of many chronic and acute diseases, the rapid quantification of toxicity in food and feed products have become a significant concern. Technology advancements in the area of biosensors, bioelectronics, miniaturization techniques, and microfluidics have shown a significant impact than conventional methods which have given a boost to improve the sensing performance towards food analyte detection. In this article, recent literature of Aflatoxin B1 (AFB1), worldwide permissible limits, major outbreaks and severe impact on healthy life have been discussed. An improvement achieved in detection range, limit of detection, shelf-life of the biosensor by integrated dimensional nanomaterials such as zero-dimension, one-dimension and two-dimension for AFB1 detection using electrical and optical transduction mechanism has been summarized. A critical overview of the latest trends using paper-based and micro-spotted array integrated with the anisotropic shape of nanomaterials, portable microfluidic devices have also been described together with future perspectives for further advancements.