Aflatoxin M1 in milk and traditional dairy products from west part of Iran: Occurrence and seasonal variation with an emphasis on risk assessment of human exposure

Review of the Terminology, Approaches, and Formulations Used in the Guidelines on Quantitative Risk Assessment of Chemical Hazards in Food

This paper reviews the published terminology, mathematical models, and the possible approaches used to characterise the risk of foodborne chemical hazards, particularly pesticides, metals, mycotoxins, acrylamide, and polycyclic aromatic hydrocarbons (PAHs). The results confirmed the wide variability of the nomenclature used, e.g., 28 different ways of referencing exposure, 13 of cancer risk, or 9 of slope factor. On the other hand, a total of 16 equations were identified to formulate all the risk characterisation parameters of interest. Therefore, the present study proposes a terminology and formulation for some risk characterisation parameters based on the guidelines of international organisations and the literature review. The mathematical model used for non-genotoxic hazards is a ratio in all cases. However, the authors used the probability of cancer or different ratios, such as the margin of exposure (MOE) for genotoxic hazards. For each effect studied per hazard, the non-genotoxic effect was mostly studied in pesticides (79.73%), the genotoxic effect was mostly studied in PAHs (71.15%), and both effects were mainly studied in metals (59.4%). The authors of the works reviewed generally opted for a deterministic approach, although most of those who assessed the risk for mycotoxins or the ratio and risk for acrylamide used the probabilistic approach.

Evaluation of Immunomodulatory Effects of Fusarium Mycotoxins Using Bacterial Endotoxin-Stimulated Bovine Epithelial Cells and Macrophages in Co-Culture

Mycotoxins are secondary metabolites produced by a variety of fungi that contaminate animal food and feeds and are capable of inducing a wide range of toxicities. Predictive in vitro models represent valuable substitutes for animal experiments to assess the toxicity of mycotoxins. The complexities of the interactions between epithelial and innate immune cells, vital for upholding barrier integrity and averting infections, remain inadequately understood. In the current study, a co-culture model of bovine epithelial cells (MAC-T) and macrophages (BoMac) was used to investigate the impact of exposure to Fusarium mycotoxins, namely deoxynivalenol (DON), zearalenone (ZEN), enniatin B (ENB), and beauvericin (BEA), on the inflammatory response elicited by the bacterial lipopolysaccharide (LPS) endotoxin. The MAC-T cells and BoMac were seeded on the apical side of a Transwell membrane and in the lower chamber, respectively, and mycotoxin exposure on the apical side of the membrane was carried out with the different mycotoxins (LC20; concentrations that elicited 20% cytotoxicity) for 48 h followed by an LPS immunity challenge for 24 h. The culture supernatants were collected from the basolateral compartment and these samples were submitted for cytokine/chemokine multiplex analysis. RNA-Seq analysis was performed using total RNA extracted from the MAC-T cells to acquire a more detailed insight into their cellular functions. The multiplex analysis indicated that IFN-γ, IL-1α, IL-8, and MCP-1 were significantly induced post-DON treatment when compared to control cells, and levels of IL-1α and IL-8 were enhanced significantly in all mycotoxin-treated groups post-LPS challenge. Analysis of the sequencing results showed that there were 341, 357, and 318 differentially expressed MAC-T cell genes that were up-regulated in the DON, ENB, and BEA groups, respectively. Gene ontology and pathway analysis revealed that these DEGs were significantly enriched in various biological processes and pathways related to inflammation, apoptosis signaling, and Wnt signaling. These results provide a comprehensive analysis of the co-culture cytokine/chemokine production and MAC-T cells' gene expression profiles elicited by Fusarium mycotoxins, which further contributes to the understanding of early endotoxemia post-mycotoxin exposure.

A national systematic literature review for aflatoxin M1 in commonly consumed cheese brands in Iran: Human health risk assessment by Monte Carlo simulation

Cheese is popular in Iran because of its high nutritional value; therefore, it is necessary to control this product regarding health risk factors, particularly aflatoxin M1 (AFM1). This research reviewed AFM1 in various varieties of cheese in Iran to assess the potential health risks associated with consuming these products for different age groups. In this regard, all accessible papers from different databases were screened between June 27, 2000 and October 10, 2022 b y systematic research and then considering the selection criteria of the studies; finally, 22 articles were selected for the current review. The amount and prevalence of AFM1 were calculated and separated based on the cheese variety, and the sampling location; health risk assessment (HRA), statistical, uncertainty, and sensitivity analysis for AFM1 of cheese for different age groups were performed. The study results for 2143 samples showed that the overall average AFM1 for cheese is 160 ± 175 ng/kg, below the European Commission (EC) regulation (250 ng/kg). AFM1 contaminated 72.42% of all cheese samples, and 13% of these contaminated samples had a higher AFM1 than the EC regulation. Cheese varieties were ranked based on average levels of AFM1 as white pasteurized > traditional > creamy > probiotic > Lighvan, and this ranking was obtained based on sampling locations as market > dairy factories > livestock farms. Based on the HRAs, from the perspective of the liver cancer risk (LCR), the margin of exposure (MOE), and the hazard index (HI) approach, it can be concluded that cheese produced in Iran, in terms of AFM1, particularly for children, poses serious health risks. Accordingly, it is imperative to carefully consider implementing suitable management methods to inhibit the growth of aflatoxin B1 (AFB1) in livestock fodder, and training in sanitary production and processing of dairy products according to world standards is suggested for industrial and traditional cheese producers across Iran.

The occurrence of aflatoxin M1 in milk samples of Iran: a systematic review and meta-analysis

In this study, the average level of aflatoxin M1 in various types of milk from 107 articles (297 studies with 16,274 milk samples) were meta-analyzed using random-effect model based on the milk varieties (animal species and heating processes), geographical regions, seasons, detection techniques and dairy farming subgroups. Studies on milk contamination with aflatoxin M1 in Iran were collected using universal and Persian databanks from January 1974 to the end of November 2021. The overall aflatoxin M1 mean concentration and prevalence in milk samples of Iran were 39.65 ng/l (95% CI: 36.00-43.30) and 80% (95% CI: 76-85%), respectively. The rank order of importance of various variables in mean levels of aflatoxin M1 in milk samples included milk type (animal species) > geographical regions > detection techniques > dairy farming types > milk types (heating processes) > seasons. Findings revealed that the overall content of aflatoxin M1 in milk samples of Iran was lower than that allowed by the European Union, Institute of Standards and Industrial Research of Iran, and the USA, possibly due to the milk monitoring by the Iranian regulatory systems.

Occurrence of Aflatoxin M1 in Cow, Goat, Buffalo, Camel, and Yak Milk in China in 2016

In this present study, 195 cow milk, 100 goat milk, 50 buffalo milk, 50 camel milk, and 50 yak milk samples were collected in China in May and October 2016. The presence of aflatoxin M1 (AFM1) was determined using enzyme-linked immunosorbent assay method. For all cow milk samples, 128 samples (65.7%) contained AFM1 in concentrations ranging from 0.005 to 0.191 µg/L, and 6 samples (3.1%) from Sichuan province in October were contaminated with AFM1 above 0.05 µg/L (EU limit). For all goat milk samples, 76.0% of samples contained AFM1 in concentrations ranging from 0.005 to 0.135 µg/L, and 9 samples (9.0%) from Shanxi province in October were contaminated with AFM1 above 0.05 µg/L. For all buffalo milk samples, 24 samples (48.0%) contained AFM1 in concentrations ranging from 0.005 to 0.089 µg/L, and 2 samples collected in October were contaminated with AFM1 above 0.05 µg/L. Furthermore, 28.0% of samples contained AFM1 in concentrations ranging from 0.005 to 0.007 µg/L in camel milk samples, and 18.0% of samples contained AFM1 in concentrations ranging from 0.005 to 0.007 µg/L in yak milk samples. Our survey study has expanded the current knowledge of the occurrence of AFM1 in milk from five dairy species in China, in particular the minor dairy species.

Co-Occurrence of <i>Staphylococcus aureus</i> and Ochratoxin A in Pasteurized Milk

Pathogens and mycotoxins are serious public health risks for humans and food safety in milk. This study concentrated on detecting <i>Staphylococcus aureus</i> and Ochratoxin A (OTA) in 210 pasteurized milk from ten urban Beijing districts to suggest the co-occurrence of <i>S. aureus</i> with toxin-producing genes and OTA in milk and the possible risk. <i>S. aureus</i> was identified by physiological and biochemical experiments and molecular biology experiments, and enterotoxin genes were identified by PCR. OTA was detected by LC-MS/MS. The study found 29 isolates of <i>S. aureus</i>, of which 17.24% had the sea gene encoding enterotoxin A. OTA was detected in 31 out of 120 samples and the maximum amount of detection was 18.8 μg/kg. The results of this study indicate that when failing to guarantee the cold chain, the presence of <i>S. aureus</i> with enterotoxin genes in milk will present a risk to food safety. Furthermore, the high detection rates and levels of OTA in milk suggest that OTA is a hidden risk. The co-occurrence of <i>S. aureus</i> and OTA in milk is a food safety concern and there is a need to control the occurrence of these two biohazards in milk.

Incidence of Aflatoxin M1 in Milk and Milk Products from Punjab, Pakistan, and Estimation of Dietary Intake

In the present study, 124 samples of milk and milk products were analyzed for the presence of aflatoxin M1 (AFM1), which were purchased from the central cities of Punjab, Pakistan. The analysis was carried out using reverse-phase liquid chromatography, which was equipped with a fluorescence detector. The results showed that 66 samples (53.8%) of raw milk and milk products were found to be contaminated with detectable levels of AFM1 above ≤50 ng/L, and 24.2% of the samples had levels of AFM1 higher than the permissible limit of the European Union (EU; 50 ng/kg). In total, 53.6% of the raw milk, 57.8% of the UHT (ultra-heat-temperature) milk, 45% of the powdered milk, 57.1% of the yogurt, 55.5% of the cheese, and 50% of the buttermilk samples had levels higher than the LOD, i.e., 4 ng/L. The highest mean of 82.4 ± 7.8 ng/kg of AFM1 was present in the positive samples of raw milk. The highest dietary intake of AFM1 was found in infants’ milk (5.35 ng/kg/day), UHT milk (1.80 ng/kg/day), powdered milk (5.25 ng/kg/day), and yogurt (1.11 ng/kg/day). However, no dietary intake was detected in the cheese and butter milk samples used for infants. The results from the undertaken work are beneficial for establishing rigorous limits for AFB1 in animal feed, especially considering the high prevalence rate of hepatitis cases in the central cities of Punjab, Pakistan.

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.

Aflatoxin M1 in distributed milks in northwestern Iran: occurrence, seasonal variation, and risk assessment

Aflatoxin is one of the dangerous fungal toxins that is produced in the presence of humidity and heat and lack of proper storage conditions and is considered as a dangerous substance threatening human health. The work aimed to determination of aflatoxin M1 (AFM) level in raw, pasteurized, and sterilized milks offered in the study area and to evaluate the risk of its consumption. In this descriptive cross-sectional study, 60 samples of milk types supplied in the region were collected during two series of sampling (cold and hot seasons) and analyzed by ELISA method. LCR, MoE, and HI indices were used to assess the possible risk of consuming milk containing AFM. In all taken samples AFM was found, the toxin concentration range in the first and second series of sampling was 57.5-270.6 ng/L and 57-185.9 ng/L, respectively. The level of toxin in pasteurized and sterilized milks in both sampling series was higher than raw milks. Based on the obtained data and in order to assess the risk of milk consumption in the target population, associated values with EDI, LCR, MoE, and HI were also calculated and obtained in the range of 0.145-0.3 ng/k.d b.w, 0.0008-0.0017 additional case per one million population, 1892.9-3921.6 and 0.72-1.5 ng/kg b.w, respectively. According to the findings, all samples tested are contaminated and although it is within the range of the WHO recommendation, however, based on the calculated indicators, the risk of liver cancer threatens the consumers of these milks. Therefore, it is necessary to manage this issue through educational control and monitoring measures.

Influence of season and lactational stage on aflatoxin M1 and ochratoxin A in human milk in a cohort study from southeastern region of Turkey

The aim was to evaluate the changes in aflatoxin M1 (AFM1) and ochratoxin A (OTA) levels in human breast milk (HBM) during the first five postpartum months according to the sampling season in a cohort study from Şanlıurfa. From 78 healthy lactating mothers, HBM was taken at the 5-14 days postpartum (D5-14) and the 6^th and 18^th weeks postpartum (W6 and W18). Mycotoxin levels were analyzed with competitive ELISA. Generalized Estimating Equations with repeated measures (three-correlation matrix dimension) revealed a significantly higher mean AFM1 level at W6 than that on D5-14. AFM1 and OTA levels in winter and spring were considerably higher than that in summer and autumn. Maternal smoke exposure, body mass index, history of moldy food exposure, birth order, and breastfeeding type did not influence the results. Whilst season had a marked effect on the milk levels of both analytes, lactation stage affected AFM1 more notable than OTA.

Aflatoxin M1 in Raw Milk, Pasteurized Milk and Cottage Cheese Collected along Value Chain Actors from Three Regions of Ethiopia

Milk is a highly nutritious and perfect natural food for humans. However, when lactating animals feed on Aflatoxin B1 (AFB1)-containing feed, the hydroxyl metabolite aflatoxin M1 (AFM1) contaminates the milk and dairy products. The objective of the current study was to assess the level of AFM1 in raw milk, normally pasteurized milk and Ethiopian cottage cheese collected from value chain actors (producers, collectors, processors and retailers). Cross-sectional study and simple random techniques were used to collect primary samples. A total of 160 composite samples was collected; raw milk (n = 64), pasteurized milk (n = 64) and cheese (n = 32) was analyzed. Quantitative analysis of AFM1 was conducted using enzyme-linked immunosorbent assay (ELISA). The results indicate that AFM1 was detected in all milk products. Results along value chains show that the concentration of AFM1 in raw milk from collectors was significantly higher than from producers, and in pasteurized milk from processors and retailers (p < 0.05). However, no significant (p > 0.05) difference was observed in cottage cheese value-chain actors in all regions. Comparison of AFM1 mean values among all dairy products shows that raw milk had a significantly higher concentration of AFM1 followed by pasteurized milk and cottage cheese. However, there was no significant difference between raw and pasteurized milk (p > 0.05). The mean AFM1 contamination in milk products ranged from 0.137 to 0.319 µg/L (mean value 0.285 µg/L). The contamination percentages of AFM1 in raw milk (62.50%), pasteurized milk (67.20%) and cottage cheese (25%) were above the regulatory limit set by the European Union (EU) (0.05 µg/L). According to USA/Ethiopian Standard (US/ES) (0.50 µg/L), 21.87%, 25% and 1% exceeded the regulatory limit for the above products, respectively. The overall prevalence (56.88%) was above the EU regulatory limit and 19.38% over US/ES regulations. Therefore, to provide accurate information about the health risk to consumers, there is a need to conduct risk assessment studies in consumers of milk and dairy products at different age groups.

The prevalence of aflatoxin M1 (AFM1) in conventional and industrial dairy products (yogurt, cheese, kashk and dough) of Iran: a systematic review and meta-analysis

Aflatoxin is a toxic metabolite produced mainly by Aspergillus spp. which may occur in dairy products because of biotransformation. In this work, a systematic and meta-analysis approach has been considered on the topic of aflatoxin M1 (AFM1) content in dairy Iranian products. Based on the literature review, AFM1 was the most common aflatoxin contamination in dairy product. Additionally, studies revealed that higher levels of AFM1 were produced during cold seasons includes winter and autumn. Although, immunochemical technique (ELISA) was the frequent and rapid test, thin-layer chromatography (TLC) and chromatographic methods (HPLC) were commonly used as confirmative techniques to determine the level of aflatoxin. Meta-analyzing of the results showed that AFM1 can be found in the dairy products with overall prevalence percentage of 63.53 (95% confidence interval [CI]: 56.28-70.78) and 54.05 (95% CI: 43.09-65.02) based on the sample type and production process, respectively. The higher prevalence percentage of AFM1 of 73.96 (95% CI: 60.27-87.66) and 69.91 (95% CI: 62.00-78.83) was found in yoghurt and industrial production type of samples, respectively. In general, 17.8% of cheese, 14% of yogurt, 12.63% of kashk, and 2.1% of doogh contained AFM1 in concentrations exceeding the permitted level of standards. Totally, results showed that 88.89% of dairy products were contaminated by AFM1 exceeding from standard limits.

Fate of aflatoxins M1 and B1 within the period of production and storage of Tarkhineh: A traditional Persian fermented food

The objective of the study was to assess the amount of aflatoxin M1 (AFM1) and aflatoxin B1 (AFB1) during fermentation, drying, and storage of Tarkhineh-a traditional Persian fermented food-over four months. Tarkhineh samples were produced based on a traditional method. Various concentrations of AFB1 (2.5, 5, 7.5, and 10 µg/kg) and AFM1, stood at 0.25, 0.5, 0.75, and 1 µg/kg, were added to Iranian yogurt drink, called doogh, samples. Tarkhineh samples were evaluated for AFB1 and AFM1 on days 0, 2, 6, and 8 and also after drying and four months of storage. In cases of repeatability, recovery, and reproducibility, the high-performance liquid chromatography through fluorescence detector (HPLC-FD) method was successfully done to demonstrate aflatoxins (AFs) in Tarkhineh samples. The fermentation process had a considerable consequence on the reduction in AFM1 and AFB1 as compared to the control group, evidenced by 65.10%-81.20% and 55.80%-74.10%, respectively, after eight days of fermentation (p < .05). The highest reduction in AFB1 existed in samples containing 2.5 µg/kg toxin, followed by 5, 7.5, and 10 µg/kg, respectively. A similar trend was found for AFM1, as the highest concentration was found in samples containing 0.25 µg/kg toxin, followed by 0.5, 0.75, and 1 µg/kg, respectively.

Mold, Mycotoxins and a Dysregulated Immune System: A Combination of Concern?

Fungi represent one of the most diverse and abundant eukaryotes on earth. The interplay between mold exposure and the host immune system is still not fully elucidated. Literature research focusing on up-to-date publications is providing a heterogenous picture of evidence and opinions regarding the role of mold and mycotoxins in the development of immune diseases. While the induction of allergic immune responses by molds is generally acknowledged, other direct health effects like the toxic mold syndrome are controversially discussed. However, recent observations indicate a particular importance of mold/mycotoxin exposure in individuals with pre-existing dysregulation of the immune system, due to exacerbation of underlying pathophysiology including allergic and non-allergic chronic inflammatory diseases, autoimmune disorders, and even human immunodeficiency virus (HIV) disease progression. In this review, we focus on the impact of mycotoxins regarding their impact on disease progression in pre-existing immune dysregulation. This is complemented by experimental in vivo and in vitro findings to present cellular and molecular modes of action. Furthermore, we discuss hypothetical mechanisms of action, where evidence is missing since much remains to be discovered.

Multi-mycotoxin occurrence in feed, metabolism and carry-over to animal-derived food products: A review

The world requests for raw materials used in animal feed has been steadily rising in the last years driven by higher demands for livestock production. Mycotoxins are frequent toxic metabolites present in these raw materials. The exposure of farm animals to mycotoxins could result in undesirable residues in animal-derived food products. Thus, the potential ingestion of edible animal products (milk, meat and fish) contaminated with mycotoxins constitutes a public health concern, since they enter the food chain and may cause adverse effects upon human health. The present review summarizes the state-of-the-art on the occurrence of mycotoxins in feed, their metabolism and carry-over into animal source foodstuffs, focusing particularly on the last decade. Maximum levels (MLs) for various mycotoxins have been established for a number of raw feed materials and animal food products. Such values are sometimes exceeded, however. Aflatoxins (AFs), fumonisins (FBs), ochratoxin A (OTA), trichothecenes (TCs) and zearalenone (ZEN) are the most prevalent mycotoxins in animal feed, with aflatoxin M₁ (AFM1) predominating in milk and dairy products, and OTA in meat by-products. The co-occurrence of mycotoxins in feed raw materials tends to be the rule rather than the exception, and the carry-over of mycotoxins from feed to animal source foods is more than proven.

Quantitative risk assessment for aflatoxin M1 associated with the consumption of milk and traditional dairy products in Argentina

A quantitative risk assessment for exposure to aflatoxin M1 (AFM₁) related to the consumption of milk and traditional dairy products of Argentina was developed. The frequency and concentration of AFM₁ was modelled at various stages through the milk processes, considering Argentinean practices. Concentration of AFM₁ (0.046 μg/l, 95%CI = 0.002-0.264 μg/l) in raw milk was estimated. The AFM₁ concentration in milk was sensitive to the carry-over rate (r = 0.80), and milk yield in the first third of lactation during the spring-summer season (r = 0.11). AFB₁ levels in silage (r = 0.22), pasture during the spring-summer season (r = 0.11), concentrate (r = 0.08), and cotton seed (r = 0.05) were the factors most correlated with AFM₁ concentrations. Although the results showed that MoE values for the mean and median exposure to AFM₁ were < 10,000 in infants, toddlers, and other children, the additional cancer risk due to exposure to AFM₁ in infants, toddlers, and other children was 0.007, 0.005, and 0.0009 additional cases per year per 100,000 individuals, respectively, which indicates no health concern. In addition, the percentages of the population exceeding HI values (HI > 1) for exposure to AFM₁ for infants, toddlers, and other children were 45%, 49.1%, and 40.6%, respectively. Under this scenario, the most susceptible population at risk was children < 10 years old; therefore, it is necessary to establish measures to prevent contamination of AFM₁ in milk and milk products.

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.

Fungal Toxins and Host Immune Responses

Fungi are ubiquitous organisms that thrive in diverse natural environments including soils, plants, animals, and the human body. In response to warmth, humidity, and moisture, certain fungi which grow on crops and harvested foodstuffs can produce mycotoxins; secondary metabolites which when ingested have a deleterious impact on health. Ongoing research indicates that some mycotoxins and, more recently, peptide toxins are also produced during active fungal infection in humans and experimental models. A combination of innate and adaptive immune recognition allows the host to eliminate invading pathogens from the body. However, imbalances in immune homeostasis often facilitate microbial infection. Despite the wide-ranging effects of fungal toxins on health, our understanding of toxin-mediated modulation of immune responses is incomplete. This review will explore the current understanding of fungal toxins and how they contribute to the modulation of host immunity.

Determination of trace aflatoxin M1 (AFM1) residue in milk by an immunochromatographic assay based on (PEI/PSS)4 red silica nanoparticles

Aflatoxin M1 (AFM1) residues in milk pose a major threat to human health, so there is an urgent need for a simple, rapid, and sensitive method for the determination of trace AFM1 in milk. In this study, a competitive immunochromatographic assay (ICA), using visual (PEI/PSS)₄ red silica nanoparticles (SiNPs) as signal amplification probes, was used for the highly sensitive detection of AFM1. The (PEI/PSS)₄ red SiNPs were used to label AFM1 monoclonal antibody (mAb) to prepare ICA for the detection of AFM1. After exploring the optimal conditions of mAb and immunoprobe dosage conditions, the lowest visual detection limit (VDL) of AFM1 in phosphate-buffered saline with Tween 20 (PBST, 10 mM, pH 7.4, containing 1% BSA, 3% sucrose, 1% trehalose, and 0.5% Tween 20) can reach 0.1 pg/mL. The intuitive visually visible value of AFM1 in both PBST and milk was 10 pg/mL. The results showed that the immunochromatographic system based on high chroma color (PEI/PSS)₄ red SiNPs has high sensitivity and broad application prospects for the detection of trace AFM1 residues in milk. The high chroma (PEI/PSS)₄ red SiNPs are expected to be a convenient biomarker for improving the sensitivity of immune chromatography bands. Graphical abstract The schematic diagram shows the detection principle. In this work, in the competitive experiment, (PEI/PSS)₄ red SiNPs were selected as visual labeling materials, and the specific antibody combined with the labeled material was selected as an immune probe. The AFM1-BSA antigen coupled with the macromolecular BSA was fixed on the T line of the nitrocellulose (NC) membrane. The AFM1 in sample solution competes with AFM1-BSA for the specific binding site of immune probe. The detection sensitivity of this method for AFM1 is obtained by judging the change of the red signal intensity produced by the positive sample, compared with the color at the T line of the negative sample.

Chemical composition and detection of Aflatoxin M1 in camels and cows milk in Sudan

A hundred samples of milk from camels and cows were analysed for chemical composition and M₁ contamination. The results indicated that camel milk from traditional nomadic systems revealed significantly (P ≤ 0.05) higher values for protein, fat, lactose, solids-not-fat and density than that obtained from camel and cows kept in semi-intensive systems. Aflatoxin (AF) M₁ was found in 33% of the milk samples with the highest occurrence (82.4%) in cow milk (35.3% ranged between 0.05 and 0.1 µ/kg and 47.1% ranged between 0.1 and 0.15 µ/kg) compared to milk samples from camel in semi-intensive systems (15.6% ranged between 0.05 and 0.1 µg/kg). All samples of milk from traditional nomadic systems revealed the absence of AFM₁. These results revealed increasing of AF with increased fat content in milk, a decrease with decreasing other milk components, while the density of milk showed no relation.

Aflatoxin M1 in Milk Worldwide from 1988 to 2020: A Systematic Review and Meta-Analysis

Background. Aflatoxins are found in various types of food and animal feed. Food contamination with aflatoxin toxin is of particular importance today. Various studies have reported different prevalence of aflatoxin M1 in animal milk. Therefore, due to the importance of this toxin, its role in health, and lack of general statistics about it worldwide, the present study aimed to determine the prevalence of aflatoxin M1 in milk worldwide with a systematic review and meta-analysis study. Methods. In this review study, national and international databases were extracted from SID, MagIran, IranMedex, IranDoc, Embase, ScienceDirect, Scopus, PubMed, and Web of Science (ISI) between January 1988 and February 2020. A random effects model was used for analysis, and heterogeneity of studies with an I2 index was investigated. Data were analyzed using Comprehensive Meta-Analysis (version 2). Results. The prevalence of aflatoxin M1 in milk worldwide from January 1988 to February 2020 in 122 articles with a sample size of 18921 was 79.1% (95% CI: 75.5–82.3%). Regarding the heterogeneity based on metaregression, there was a significant difference between the effect of the year of study (p≤0.001) and sample size (p≤0.001) with the prevalence of aflatoxin M1 in animal milk. Conclusion. The results of this study show that the prevalence of aflatoxin M1 in milk is high worldwide. Therefore, considering the importance of the milk group and its products, special measures should be taken to protect the ration from aflatoxin molds and milk quality.

Assessment of aflatoxin in milk and feed samples and impact of seasonal variations in the Punjab, Pakistan

The present study was designed to assess the incidence of aflatoxin contamination in animal feed and raw milk samples (total 240 each) collected from dairy farms during the complete year of 2015. These samples were collected through a cluster random sampling technique by dividing the province of Punjab, Pakistan into five clusters (north, south, east, west and central). Factors (environmental & physical) affecting aflatoxin contamination in milk and animal feed at farms were also studied. The AFM1 levels in raw milk & AFB1 levels in feed samples were analyzed by using the ELISA technique. Results demonstrated that overall about 53% raw milk samples from dairy farms were contaminated beyond the US MRL (0.50 µg/L) for AFM1 with than average level of 0.59 µg/L, while the 95% farm feed samples were exceeding the FDA MRL (20 µg/kg) of AFB1 with average level of 43 µg/kg. During winter season, the concentration of AFM1 was higher in all clusters with avg 0.68 µg/L, while the AFB1 contamination was highest in the spring season with avg 54 µg/kg. Market feed prices had negative correlation with AFB1 contamilevels, which were further supported by the positive correlation between quantity of feed at farms with AFM1 and AFB1 contamination. Results exhibited significantly positive impact of environmental factors on milk and feed aflatoxin contamination levels, whereas temperature showed an inverse relationship with AFM1 and AFB1 levels. The study recommends need of synergistic extension work to support dairy farms and highlight the contamination levels for regulatory bodies to introduce strategic policies for control measures.

Two-year survey on the seasonal incidence of aflatoxin M1 in traditional dairy products in Egypt

The most popular and economically important traditional dairy products in Egypt are raw milk, Karish cheese (an Arabian dairy product made from defatted cow milk) and Zabady (an Arabian yoghurt made from buffalo and cow milk). In this study, 302 traditional dairy samples including raw milk (120), white Karish cheese (118), and Zabady (64) were analyzed for aflatoxin M1 (AFM1) during different seasons in 2016 and 2017. Contamination of raw milk samples with AFM1 was 21.6% and 18.3% in samples collected in the two respective years with percentages of 100% and 90.9% exceeding the legal European limit (0.05 µg L^-1). In Karish cheese samples, the contamination level was 33.9% and 44.6%, in the 2 years examined with percentages of 90.47% and 80% that were above the European limit (0.25 µg kg^-1). In the case of Zabady, the AFM1-positive samples were 12.5% and 18.75%, and all of them were above the European limit (0.25 µg kg^-1). However, average toxin concentration in Zabady was lower than that detected in milk and cheese. Despite the seasonal variations influencing the occurrence of AFM1 in the three dairy products, the AFM1 levels in samples collected in winter were significantly (P ≤ 0.001) greater than those collected in summer. The contamination levels of AFM1 in the traditional dairy products consumed in Egypt; represent a serious health risk. It is urgent to inspect dairy farms for contamination with aflatoxins in a regular manner.

Characteristics, Occurrence, Detection and Detoxification of Aflatoxins in Foods and Feeds

Mycotoxin contamination continues to be a food safety concern globally, with the most toxic being aflatoxins. On-farm aflatoxins, during food transit or storage, directly or indirectly result in the contamination of foods, which affects the liver, immune system and reproduction after infiltration into human beings and animals. There are numerous reports on aflatoxins focusing on achieving appropriate methods for quantification, precise detection and control in order to ensure consumer safety. In 2012, the International Agency for Research on Cancer (IARC) classified aflatoxins B1, B2, G1, G2, M1 and M2 as group 1 carcinogenic substances, which are a global human health concern. Consequently, this review article addresses aflatoxin chemical properties and biosynthetic processes; aflatoxin contamination in foods and feeds; health effects in human beings and animals due to aflatoxin exposure, as well as aflatoxin detection and detoxification methods.

Occurrence and seasonal variation of aflatoxin M1 in raw cow milk collected from different regions of Algeria

Background and Aim:

Aflatoxins are metabolites of molds that exert potentially toxic effect on animals and humans. This study aimed to investigate the occurrence of aflatoxin M₁ (AFM₁) in raw cow milk collected during 1 year (2016-2017) from different regions of Algeria and risk factors associated with the contamination.

Materials and Methods:

During the survey period, 84 samples of raw milk were collected in three regions of Algeria (northeast, north center, and northwest) during four seasons. AFM₁ levels were analyzed by competitive enzyme-linked immunosorbent assay.

Results:

AFM₁ was detected in 39 (46.43%) samples (total mean concentration, 71.92 ng/L; range, 95.59-557.22 ng/L). However, the AFM₁ levels exceeded the maximum tolerance limit set by the Food and Drug Administration in the USA (500 ng/L) in only 1 sample (1.19%). Statistical analysis revealed significant differences (p˂0.005) between AFM₁ levels in milk samples collected in the spring and autumn. The mean AFM₁ levels in samples collected in the spring were significantly higher than those in samples collected in autumn.

Conclusion:

The survey indicates that farmers involved in milk production should be made aware of the adverse effects of aflatoxin contamination in animal feed. A systematic control program of supplementary feedstuff for lactating cows should be introduced by the public health authorities.

Specific monitoring of aflatoxin M1 in real samples using aptamer binding to DNFS based on turn-on method: A novel biosensor

In the present work, a novel biocompatible scaffold was fabricated for the DNA aptamer immobilization. For the first time, amino-functionalized dendritic fibrous nanosilica (KCC-1-nPr-NH₂ ) and gold nanoparticle supported by chitosan (AuNPs-CS) were synthesized and electrodeposited successfully on the surface of the glassy carbon electrode by chronoamperometry technique. Unique oligonucleotide of aflatoxin M1 (5'-ATC CGT CAC ACC TGC TCT GAC GCT GGG GTC GAC CCG GAG AAA TGC ATT CCC CTG TGG TGT TGG CTC CCG TAT) labeled by toluidine blue was immobilization on the prepared interface. Hence, a novel aptamer-based bioassay was formed for highly sensitive quantitation of AFM1 using cyclic voltammetry and differential plus voltammetry. The structure and morphology of GQDs-CS/KCC-1-nPr-NH₂ were investigated by Fourier-transform infrared spectroscopy, X-ray diffraction, atomic force, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The achieved low limit of quantification of apta-assay for detection of AFM1 was 10fM. Also, calibration curve was linear from 0.1μM to 10fM in real samples. The proposed apta-assay has acceptable long-term stability. Designed aptasensor has a lot of remarkable advantages including excellent selectivity, sensitivity, and stability that could be used as facile bio-device for the determination of AFM1 in milk samples.

Practical analysis of aflatoxin M1 reduction in pasteurized Milk using low dose gamma irradiation

Milk and dairy products can be exposed to potential dangers such as aflatoxin M1 (AFM1). Various factors affect the formation of aflatoxin, which can be due to environmental changes and the lack of suitable substrate for healthy livestock feeding. The goal of this study is to reduce the toxin in pasteurized milk to a level below the European Codex Alimentarius Commission standard. For this purpose, the proper structure of the radioactive granite stone was first designed as a low level gamma irradiation (LLGI) without contact with pasteurized milk, and and the pasteurized milk containing AFM1 that placed in this structure is measured and compared with the control sample values using Association of Official Analytical Chemists (AOAC) method. Then, the reduction of the resulting aflatoxin in the milk and the LLGI dose rate are obtained. The LLGI dose rate is calculated using the Monte Carlo N-Particle Transport Code (MCNP). For simulation, in addition to the spectrum of gamma radiation emitted by radioactive granites, weight percent of each composition of the pasteurized milk and its component elements are also calculated. The results showed a 51.5% reduction of aflatoxin in pasteurized milk after 4 days and 99% reduction after 8 days compared to the control sample. The LLGI dose rate in milk is 0.39 mGy per day. According to the international atomic energy agency (IAEA) report and pervious results, this dose rate level does not significantly affect chemical and sensory quality of milk, but can extend the shelf-life and provide a safer milk. Therefore, the structure constructed using radioactive granite in this study can be considered as one of the suitable methods for reducing aflatoxin.

The overall and variations of Aflatoxin M1 contamination of milk in Iran: A systematic review and meta-analysis study

Major databases were searched until January 2019 and 77 eligible studies were included in the meta-analysis to estimate the overall mean of AFM1 in milk in Iran. The mean of AFM1 levels was obtained 55.97 ng/kg (95% CI: 50.09-61.84). However, the pooled estimated mean of AFM1 levels in milk were 94.58 (95% CI: 70.24-118.92), 59.19 (95% CI: 51.84-66.54) and 35.23 ng/kg (95% CI: 31.53-38.92), considering 4, 55 and 18 TLC, ELISA and HPLC-based studies (including 354, 9224 and 2606 samples), respectively. Also, there is a wide variation of AFM1 levels among different geographical regions which were the highest in northern (88.77 ng/kg). The AFM1 contamination of milk taken from the areas with humid climate was higher than the arid climate. AFM1 Levels were the highest in winter (48.70 ng/Kg). The level of AFM1 in pasteurized, raw, and UHT milk were 49.76, 55.08 and 94.81 ng/kg, respectively.