Exposure assessment of Portuguese infants to Aflatoxin M1 in breast milk and maternal social-demographical and food consumption determinants

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.

Evaluating postnatal exposure to six heavy metals in a Chinese e-waste recycling area

This study is the first to assess postnatal exposure to heavy metals using breast milk in an electronic waste (e-waste) recycling area. From January to April 2021, 102 and 97 breastfeeding women were recruited from an e-waste recycling area and a control area, respectively. Four weeks after delivery, medical staff collected 20 mL of breast milk from each participant. The breast milk was tested for six heavy metals (lead, cadmium, chromium, arsenic, copper, and manganese) using inductively coupled plasma mass spectrometry (ICP-MS). The estimated daily intake (EDI) of infants during breastfeeding was calculated to assess the impact of postnatal exposure to heavy metals on infant health. The concentrations of chromium and lead in the breast milk were significantly higher in the e-waste recycling area than in the control area. Chromium concentrations in breast milk was 34.3%, exceeding the permissible limits set by the World Health Organization (WHO), in the e-waste recycling area, which is 16 times higher than that in the control areas. The EDIs of lead and chromium in the e-waste area were twice as those in the control area. This strongly indicates that the potential impact of postnatal exposure to lead and chromium on infant and child health in e-waste recycling areas cannot be ignored. Infants and children in e-waste recycling areas are at risk of long-term exposure to heavy metals. Therefore, ongoing health monitoring is necessary.

High speed homogenization assisted encapsulation of synergistic essential oils formulation: Characterization, in vitro release study, safety profile, and efficacy towards mitigation of aflatoxin B1 induced deterioration in rice samples

Application of essential oils to mitigate aflatoxin B₁ (AFB₁) contamination in food is a current research hotspot; however, their direct incorporation may cause toxic effects, and changes in food organoleptic properties. This work aimed to synthesize novel synergistic formulation of Pinus roxburghii, Juniperus communis, and Cupressus sempervirens essential oils by mixture design assay (PJC) and encapsulation of PJC formulation into chitosan nanocomposite (Nm-PJC) with an aim to protect stored rice (Oryza sativa L., prime staple food) against fungi and AFB₁ mediated loss of valuable minerals, macronutrients, and fatty acids. Nm-PJC was characterized through DLS, SEM, FTIR, and XRD analyses, along with controlled delivery from chitosan nanobiopolymer. Encapsulation of synergistic formulation into chitosan-nanomatrix improved antifungal (4.0 μL/mL), antiaflatoxigenic (3.5 μL/mL), and antioxidant activities (P < 0.05). Impairment in ergosterol and methylglyoxal biosynthesis along with in-silico-homology-modeling of major components with Ver-1 and Omt-A proteins advocated chemico-molecular interaction responsible for fungal growth inhibition and AFB₁ secretion. In addition, in-situ efficacy against lipid-peroxidation, fatty acid biodeterioration, and preservation of minerals, macronutrients without affecting organoleptic attributes in rice and high mammalian safety profile (9874.23 μL/kg) suggested practical application of synergistic nanoformulation as innovative smart, and green candidate to mitigate AFB₁ contamination, and shelf-life extension of stored food products.

Mycotoxins Exposure in Cabinda, Angola—A Pilot Biomonitoring Survey of Breastmilk

Breast milk is considered the ideal form of nutrition for newborns and infants. However, it can carry over contaminants, namely mycotoxins, with biological effects to which this population is particularly vulnerable. Human biomonitoring and surveillance programs are particularly scarce in low-income countries, where food security is a more urgent priority in comparison with food safety. This pilot survey aims to assess exposure of breastfed infants to aflatoxin M1 (AFM1), zearalenone (ZEN), and ochratoxin A (OTA) in Angola, and to evaluate the main socio-demographical and food consumption determinants of lactating mothers. All 37 breast milk samples analyzed are found to be contaminated with ZEN and OTA, although none are found contaminated with AFM1. Contamination levels are lower than previously reported for ZEN but higher in the case of OTA. A significant association between ZEN levels in breast milk and the consumption of cookies by the lactating mothers is found. As for OTA, higher levels are observed in the milk from mothers with younger infants, for which high estimated daily intake (EDI) is determined. As far as the authors are aware, this is the first survey of the occurrence of mycotoxins in breast milk in Angola, so further human biomonitoring works should follow, given that mycotoxins are a global health issue that directly impact the health of populations.

Levels of Aflatoxin M1 in Breast Milk of Lactating Mothers in Monterrey, Mexico: Exposure and Health Risk Assessment of Newborns

The present study aimed to determine the presence of the aflatoxin M1 (AFM1) in breast milk samples from 123 nursing women and the degree of exposure of infants to this toxin, in the metropolitan area of Monterrey, Nuevo Leon state (northeast Mexico). Upon analysis, 100% of the samples were found to be contaminated with the toxin at an average concentration of 17.04 ng/L, with a range of 5.00 to 66.23 ng/L. A total of 13.01% of the breast milk samples exceeded the regulatory limit of 25 ng/L for AFM1 concentration, set by the European Union. The estimated daily intake for AFM1 and the carcinogenic risk index were also determined in the 0- to 6-, 7- to 12-, 13- to 24-, and 25- to 36-month-old age groups. The AFM1 intake through breast milk ranged from 1.09 to 20.17 ng/kg weight/day, and was higher than the tolerable daily intake, indicating a carcinogenic risk for infants in the age groups of 0- to 24-months old. This evidence demonstrates a susceptibility of breast milk to AFM1 contamination that may suggest a carcinogenic risk for the breastfed infants in Monterrey city, Nuevo Leon state, and the need to control the presence of aflatoxins in foods eaten by nursing mothers.

Mycotoxin Exposure during the First 1000 Days of Life and Its Impact on Children’s Health: A Clinical Overview

The first 1000 days of life are very sensitive to any event that alters health programming, and they represent a window for intervention to improve population health. Pregnant women, fetuses, and infants are particularly vulnerable to exposure to food contaminated with mycotoxins. This review aimed to gather data from the literature on mycotoxins exposure during intrauterine life and early childhood, and associated health risks, as assessed through human biomonitoring and mycotoxins occurrence in foods, in different continents. Maternal internal exposure to aflatoxins is associated with fetal growth restriction, while exposure to fumonisins increases the risk of offspring’s neural tube defects. Mycotoxin contamination of breast milk is reported worldwide, but data on adverse effects of the lactational transfer of mycotoxins on infant health are lacking. Young children are exposed to mycotoxins through contaminated infant formulas and baby foods. Both external and internal exposure to aflatoxins and fumonisins in children are reported to be associated with growth impairment. In low-income settings, where other co-factors can affect growth, this association should be interpreted with caution. Further studies on human biomonitoring of mother–infant pairs and young children are needed to guide management strategies aiming to minimize mycotoxin exposure at critical developmental stages.

Human Biomonitoring of Selected Hazardous Compounds in Portugal: Part II—Lessons Learned on Mycotoxins

Human biomonitoring (HBM) data provide information on total exposure regardless of the route and sources of exposure. HBM studies have been applied to quantify human exposure to contaminants and environmental/occupational pollutants by means of determining the parent compounds, their metabolites, or even their reaction products in biological matrices. HBM studies performed among the Portuguese population are dispersed and limited. Thus, to overcome this knowledge gap, this work reviews the published Portuguese HBM information concerning mycotoxins detected in the urine, serum, milk, hair, and nails of different groups of the Portuguese population. This integrative approach to the available HBM data allows us to analyze the main determinants and patterns of exposure of the Portuguese population to the selected hazardous compounds, as well as to assess the potential health risks. We also aimed to identify the main difficulties and challenges of HBM through the analysis of the enrolled studies. Ultimately, this study aims to support national and European policies in promoting human health by summarizing the most important outcomes and lessons learned through the HBM studies carried out in Portugal.

Adsorbents Reduce Aflatoxin M1 Residue in Milk of Healthy Dairy Cow Exposed to Moderate Level Aflatoxin B1 in Diet and Its Exposure Risk for Humans

This study investigated the effect of moderate risk level (8 µg/kg) AFB₁ in diet supplemented with or without adsorbents on lactation performance, serum parameters, milk AFM₁ content of healthy lactating cows and the AFM₁ residue exposure risk in different human age groups. Forty late healthy lactating Holstein cows (270 ± 22 d in milk; daily milk yield 21 ± 3.1 kg/d) were randomly assigned to four treatments: control diet without AFB₁ and adsorbents (CON), CON with 8 μg/kg AFB₁ (dry matter basis, AF), AF + 15 g/d adsorbent 1 (AD1), AF + 15 g/d adsorbent 2 (AD2). The experiment lasted for 19 days, including an AFB₁-challenge phase (day 1 to 14) and an AFB₁-withdraw phase (day 15 to 19). Results showed that both AFB₁ and adsorbents treatments had no significant effects on the DMI, milk yield, 3.5% FCM yield, milk components and serum parameters. Compared with the AF, AD1 and AD2 had significantly lower milk AFM₁ concentrations (93 ng/L vs. 46 ng/L vs. 51 ng/L) and transfer rates of dietary AFB₁ into milk AFM₁ (1.16% vs. 0.57% vs. 0.63%) (p < 0.05). Children aged 2–4 years old had the highest exposure risk to AFM₁ in milk in AF, with an EDI of 1.02 ng/kg bw/day and a HI of 5.11 (HI > 1 indicates a potential risk for liver cancer). Both AD1 and AD2 had obviously reductions in EDI and HI for all population groups, whereas, the EDI (≥0.25 ng/kg bw/day) and HI (≥1.23) of children aged 2–11 years old were still higher than the suggested tolerable daily intake (TDI) of 0.20 ng/kg bw/day and 1.00 (HI). In conclusion, moderate risk level AFB₁ in the diet of healthy lactating cows could cause a public health hazard and adding adsorbents in the dairy diet is an effective measure to remit AFM₁ residue in milk and its exposure risk for humans.

Evaluation of Mycotoxins in Infant Breast Milk and Infant Food, Reviewing the Literature Data

In this review, an analysis focusing on mycotoxin determination in infant breast milk and infant food has been summarised for the last fifteen years of research focused on the intended population group of 1-9 months. The objective was to know the level of exposure of the child population to an estimated daily intake (EDI) of mycotoxins from the consumption of habitual foods. The EDI was compared with the tolerable daily intake (TDI) established by EFSA to estimate risk. In breast milk, the high prevalence and levels were for samples from Africa (Egypt and Tanzania) with aflatoxin M1 (1.9 μg/L and 10%), and Asia (Iran) with ochratoxin-A (7.3 μg/L and 100%). In infant formulas, high incidences and values were for samples with aflatoxin M1 from Burkina Faso (167 samples, 84%, 87 μg/kg). In cereal products, the highest incidence was for DON from the United States (96 samples), and the highest value was an Italian sample (0.83 μg/kg of enniatin B). In fruit products, patulin was the most detected in Italian (78) and Spanish (24) samples. The highest risk was observed in breast milk during the first month of age, the highest EDI for aflatoxin M1 was reported for Egypt (344-595 ng/kg bw/day) and ochratoxin-A for Iran (97-167ng/kg bw/day), representing a public health problem.

Mycotoxin occurrence in breast milk and exposure estimation of lactating mothers using urinary biomarkers in São Paulo, Brazil

In this study, the occurrence of aflatoxins (AFs), fumonisins (FBs), ochratoxin A (OTA), deoxynivalenol (DON), zearalenone (ZEN) and some of their metabolites were assessed in breast milk and urine of lactating women (N = 74) from Pirassununga, São Paulo, Brazil. Exposure estimations through urinary mycotoxin biomarkers was also performed. Samples were collected in four sampling times (May and August 2018, February and July 2019) and analyzed by liquid chromatography coupled to tandem mass spectrometry. Aflatoxin M₁ (AFM₁) was not detected in breast milk. However, two samples (3%) presented FB₁ at 2200 and 3400 ng/L, while 4 samples (5%) had OTA at the median level of 360 ng/L. In urine, AFM₁ and aflatoxin P₁ (AFP₁) were found in 51 and 11% of samples, respectively (median levels: 0.16 and 0.07 ng/mg creatinine, respectively). Urinary DON (median level: 38.59 ng/mg creatinine), OTA (median level: 2.38 ng/mg creatinine) and ZEN (median level: 0.02 ng/mg of creatinine) were quantified in 18, 8 and 10% of the samples, respectively. Mean probable daily intake (PDI) values based on urinary biomarkers were 1.58, 1.09, 5.07, and 0.05 μg/kg body weight/day for AFM₁, DON, OTA, and ZEN, respectively. Although a low mycotoxin occurrence was detected in breast milk, the PDI for the genotoxic AFs was much higher than those reported previously in Brazil, while PDI values obtained for OTA and DON were higher than recommended tolerable daily intakes. These outcomes warrant concern on the exposure of lactating women to these mycotoxins in the studied area.

Risk of dietary and breastmilk exposure to mycotoxins among lactating women and infants 2-4 months in northern India

Mycotoxins are carcinogenic secondary metabolites of fungi that have been linked to infant growth faltering. In this study, we quantified co-occurring mycotoxins in breast milk and food samples from Haryana, India, and characterized determinants of exposure. Deterministic risk assessment was conducted for mothers and infants. We examined levels of eight mycotoxins (Aflatoxin B1 , B2 , G1 , G2 , M1 , M2 ; Ochratoxin A, B) in 100 breast milk samples (infants 2-4 months) using ultra-high-performance liquid chromatography tandem mass spectrometry. Aflatoxin B1 (AFB1 ), fumonisin B1 (FB1 ) and deoxynivalenol (DON) were detected in several food items (n = 298) using enzyme-linked immunosorbent assays. We report novel data on the presence of mycotoxins in breast milk samples from India. Whereas breast milk concentrations (AFM1 median: 13.7; range: 3.9-1200 ng/L) remain low, AFM1 was detected above regulatory limits in 27% of animal milk samples. Additionally, 41% of infants were above provisional maximum tolerable daily intake (PMTDI) limits for AFM1 due to consumption of breast milk (mean: 3.04, range: 0.26-80.7 ng kg-1 bw day-1 ). Maternal consumption of breads (p < 0.05) was associated with breast milk AFM1 exposure. AFB1 (μg/kg) was detected in dried red chilies (15.7; 0-302.3), flour (3.13; 0-214.9), groundnuts (0; 0-249.1), maize (56.0; 0-836.7), pearl millet (1.85; 0-160.2), rice (0; 0-195.6), wheat (1.9; 0-196.0) and sorghum (0; 0-63.5). FB1 (mg/kg) was detected in maize (0; 0-61.4), pearl millet (0; 0-35.4) and sorghum (0.95; 0-33.2). DON was not detected in food samples. Mothers in our study exceeded PMTDI recommendations for AFB1 due to consumption of rice and flour (mean: 75.81; range: 35.2-318.2 ng kg-1 bw day-1 ). Our findings show the presence of Aflatoxin B1 and M1 at various levels of the food chain and in breast milk, with estimated intakes exceeding PMTDI recommendations. Aflatoxins are known carcinogens and have also been linked to stunting in children. Their presence across the food system and in breast milk is concerning, thus warranting further research to replicate and expand on our findings and to understand implications for maternal and child health.

Mycotoxin Occurrence, Exposure and Health Implications in Infants and Young Children in Sub-Saharan Africa: A Review

Infants and young children (IYC) remain the most vulnerable population group to environmental hazards worldwide, especially in economically developing regions such as sub-Saharan Africa (SSA). As a result, several governmental and non-governmental institutions including health, environmental and food safety networks and researchers have been proactive toward protecting this group. Mycotoxins, toxic secondary fungal metabolites, contribute largely to the health risks of this young population. In SSA, the scenario is worsened by socioeconomic status, poor agricultural and storage practices, and low level of awareness, as well as the non-establishment and lack of enforcement of regulatory limits in the region. Studies have revealed mycotoxin occurrence in breast milk and other weaning foods. Of concern is the early exposure of infants to mycotoxins through transplacental transfer and breast milk as a consequence of maternal exposure, which may result in adverse health effects. The current paper presents an overview of mycotoxin occurrence in foods intended for IYC in SSA. It discusses the imperative evidence of mycotoxin exposure of this population group in SSA, taking into account consumption data and the occurrence of mycotoxins in food, as well as biomonitoring approaches. Additionally, it discusses the health implications associated with IYC exposure to mycotoxins in SSA.

Exposure of nursing mothers to polycyclic aromatic hydrocarbons: Levels of un-metabolized and metabolized compounds in breast milk, major sources of exposure and infants' health risks

In this study, biomonitoring of nursing Portuguese mothers to polycyclic aromatic hydrocarbons (PAHs) exposure and assessment of potential health risks of their infants were performed through determination of 18 PAHs and 6 major metabolites (OH-PAHs) in breast milk. Concentrations of total PAHs ranged between 55.2 and 1119 ng/g fat, being naphthalene, dibenz(a,h)anthracene, benzo(g,h,i)perylene, and phenanthrene the most abundant compounds (68.4% of ∑PAHs). Benzo(a)pyrene, known carcinogenic, was not detected. Total levels of OH-PAHs ranged from 6.66 to 455 ng/g fat with 1-hydroxyphenanthrene, 1-hydroxynaphthalene and 1-hydroxyacenaphthene as major compounds (96% of ∑OH-PAHs). Concentrations of ∑PAHs and ∑OH-PAHs were strongly correlated between each other (r = 0.692; p ≤ 0.001) and moderately-to-strongly associated with individual compounds (0.203 < r < 0.841; p ≤ 0.001). The attained data suggest increased levels of PAHs in older nursing mothers (>30 years) and in those whose child had lower weight (up to 3.0 kg). Breast-fed infant presented a median PAHs daily intake of 1.41 μg/kg body weight (total benzo(a)pyrene equivalents of 0.0679 μg/kg) and were exposed to 0.024 μg/kg body weight of ∑PAH4 [benz(a)anthracene, benzo(b)fluoranthene, benzo(j)fluoranthene, and chrysene]. Although breast milk is a secure food for newborns, un-metabolized and metabolized PAHs should be included in biomonitoring surveillance studies during breastfeeding to prevent potential health risks for infants.

Occurrence of and Factors Associated With the Presence of Aflatoxin M1 in Breast Milk of Mothers in Fethiye, Turkey

Aflatoxins comprise a group of mycotoxins that are found in the environment. Exposure to aflatoxins has been reported to cause serious health problems in humans. Since aflatoxin M₁ (AFM₁) is secreted in breast milk, the exposure of infants to this toxin is an important concern. The aim of this study was to determine the prevalence, levels of, and factors associated with the presence of AFM₁ in breast milk of mothers in Fethiye, Turkey. Breast milk samples were taken from 100 mothers who had given birth over the period of October-November 2017. The AFM₁ content of the samples was determined via enzyme-linked immunosorbent assay. The lowest limit for milk samples in the Ridascreen® AFM₁ commercial test kit is 5 ng/L. Because of this, AFM₁ levels below 5 ng/L in the breast milk samples were assessed as negative. Of the breast milk samples tested, 53 were positive. The average AFM₁ amount in the positive samples was 6.36 ng/L (ppt; range 5.10-8.31 ng/L). Mothers who were housewives, lived in damp, humid houses, or ate spices or dried fruits and vegetables had significantly greater prevalence of AFM₁ in their breast milk than those who were employed, did not report dampness or mold in the home, or did not eat spices or dried fruits and vegetables. AFM₁ in breast milk could be an important risk factor for infant health. Informing the public about food safety could reduce the amount of AFM₁ being transferred into breast milk via food channels.

Burden of disease associated with dietary exposure to carcinogenic aflatoxins in Portugal using human biomonitoring approach

Human biomonitoring is an important tool to assess human exposure to chemicals, contributing to describe trends of exposure over time and to identify population groups that could be under risk. Aflatoxins are genotoxic and carcinogenic food contaminants causing hepatocellular carcinoma, the third leading cause of cancer deaths worldwide. In Portugal, scarce data are available regarding exposure to aflatoxins and no previous study used human biomonitoring data to comprehensively characterize the associated burden of disease. 24 h urine and first-morning urine paired samples were collected by 94 participants and were analyzed by liquid chromatography-tandem mass spectrometry for the quantitative determination of aflatoxins (B₁, B₂, G₁, G₂ and M₁). Deterministic and probabilistic models were developed to assess the Portuguese exposure to aflatoxins and to estimate the health impact of this exposure, estimating the attributed Disability-Adjusted Life Years (DALYs). Aflatoxins were detected in a maximum of 13% (AFB₁), 16% (AFB₂), 1% (AFG₁), 2% (AFG₂) and 19% (AFM₁) of the urine samples. Data obtained through the probabilistic approach revealed an estimated mean probable daily intake of 13.43 ng/kg body weight per day resulting in 0.13 extra cases of hepatocellular carcinoma, corresponding to mean annual DALYs of 172.8 for the Portuguese population (10291027 inhabitants). The present study generated for the first time and within a human biomonitoring study, reliable and crucial data to characterize the burden associated to the exposure to aflatoxins of the Portuguese population. The obtained results constitute an imperative support to risk managers in the establishment of preventive policy measures that contribute to ensure public health protection.

Risk assessment of aflatoxins in food

EFSA was asked to deliver a scientific opinion on the risks to public health related to the presence of aflatoxins in food. The risk assessment was confined to aflatoxin B1 (AFB1), AFB2, AFG1, AFG2 and AFM1. More than 200,000 analytical results on the occurrence of aflatoxins were used in the evaluation. Grains and grain-based products made the largest contribution to the mean chronic dietary exposure to AFB1 in all age classes, while 'liquid milk' and 'fermented milk products' were the main contributors to the AFM1 mean exposure. Aflatoxins are genotoxic and AFB1 can cause hepatocellular carcinomas (HCCs) in humans. The CONTAM Panel selected a benchmark dose lower confidence limit (BMDL) for a benchmark response of 10% of 0.4 μg/kg body weight (bw) per day for the incidence of HCC in male rats following AFB1 exposure to be used in a margin of exposure (MOE) approach. The calculation of a BMDL from the human data was not appropriate; instead, the cancer potencies estimated by the Joint FAO/WHO Expert Committee on Food Additives in 2016 were used. For AFM1, a potency factor of 0.1 relative to AFB1 was used. For AFG1, AFB2 and AFG2, the in vivo data are not sufficient to derive potency factors and equal potency to AFB1 was assumed as in previous assessments. MOE values for AFB1 exposure ranged from 5,000 to 29 and for AFM1 from 100,000 to 508. The calculated MOEs are below 10,000 for AFB1 and also for AFM1 where some surveys, particularly for the younger age groups, have an MOE below 10,000. This raises a health concern. The estimated cancer risks in humans following exposure to AFB1 and AFM1 are in-line with the conclusion drawn from the MOEs. The conclusions also apply to the combined exposure to all five aflatoxins.

Occurrence of Aflatoxin M1 in Raw Milk Marketed in Italy: Exposure Assessment and Risk Characterization

The current study is based on the AFM₁ contamination of milk determined from April 2013 to December 2018 in the framework of a self-control plan of six milk processing plants in Italy. These data – together with the consumption data of milk consumers – were evaluated and used for the calculation of the Estimated Daily Intake (EDI), the Hazard Index (HI), and the fraction of hepatocarcinoma cases (HCC) due to AFM₁ exposure in different population groups. Altogether a total of 31,702 milk samples were analyzed, representing 556,413 tons of milk, which is an outstanding amount compared to published studies. The results indicate the monthly fluctuation of AFM₁ levels through a period of nearly 6 years. The EDI of AFM₁ in different population groups was in the range of 0.025–0.328 ng kg⁻¹ body weight (bw) per day, based on the average consumption levels and weighted mean contamination of the milk in the study period. Considering average consumptions, in the groups of infants and toddlers, the HI calculation resulted in 1.64 and 1.4, respectively, while for older age groups, it was <1. The estimated fractions of HCC incidences attributable to the AFM₁ intakes were 0.005 and 0.004 cases per 100,000 individuals in the 0–0.9 and 1–2.9-year age groups, respectively, and below 0.004 cases in the other age categories. The monthly average AFM₁ contamination of tested milk consignments ranged between 7.19 and 22.53 ng kg⁻¹. Although the results of this extensive investigation showed a low risk of HCC, the variability of climatic conditions throughout years that influence AFB₁ contamination of feed and consequently AFM₁ contamination of milk justifies their continuous monitoring and update of the risk assessment.

Surface screening, molecular modeling and in vitro studies on the interactions of aflatoxin M1 and human enzymes acetyl- and butyrylcholinesterase

Aflatoxin M1 (AFM1) is a mycotoxin produced by Aspergillus fungi and found in contaminated milk, breastfeed and dairy products, being highly toxic and carcinogenic to humans and other mammalian species. It is also produced in the human body as a metabolite of aflatoxin B1 (AFB1), one of the most toxic natural products known. Previous studies have shown that AFM1 is a potential inhibitor of the enzyme acetylcholinesterase (AChE), and therefore, a potential neurotoxic agent. In this work, surface screening (SS) and molecular dynamics (MD) simulation on human acetylcholinesterase AChE (HssAChE) were performed to corroborate literature data regarding preferential binding sites and type of inhibition. Also, an inedited theoretical study on the interactions of AFM1 with human butyrylcholinesterase (HssBChE) was performed. In vitro inhibition tests on both enzymes were done to support theoretical results. MD simulations suggested the catalytic anionic site of HssAChE as the preferential binding site for AFM1 and also that this metabolite is not a good inhibitor of HssBChE, corroborating previous studies. In vitro assays also corroborated molecular modeling studies by showing that AFM1 did not inhibit BChE and was able to inhibit AChE, although not as much as AFB1.

Concentration and Prevalence of Aflatoxin M1 in Human Breast Milk in Iran: Systematic Review, Meta-Analysis, and Carcinogenic Risk Assessment: A Review

This meta-analysis was designed to review the published reports regarding the concentration and/or prevalence of aflatoxin M₁ (AFM₁) in human breast milk in Iran. The carcinogenic risk for Iranian infants consuming this milk was estimated with the hazard index. The PubMed and Scopus databases and the Scientific Information Database were screened for relevant studies between 1995 and 2017, and 11 of the 112 collected studies were included in the systematic review and meta-analysis. The mean (95% confidence interval) concentration of AFM₁ was 5.85 ng/L (4.54 to 7.15 ng/L), which was lower than the European Union standard (25 ng/L). The mean prevalence of AFM₁ in breast milk in Iran was 42% (11 to 77%). The estimated daily intakes for male and female infants were 0.02 to 5.57 ng/kg and 0.02 to 3.68 ng/kg of body weight per day, respectively. The rank order of estimated daily intake for both male and female infants according to age was 1 week > 1 month > 6 months > 12 months. The hazard index for all age groups of infants in all provinces in Iran was less than 1. Therefore, infants in Iran were not considered at carcinogenic risk from AFM₁ in human breast milk.