Probabilistic risk assessment of dietary exposure to aflatoxin B1 in Guangzhou, China

Identification of Mutagenicity, MOA, and Dose Response Analysis

Bates et al. (2023) developed a cancer risk assessment framework to evaluate dietary carcinogens. The framework 1) evaluates gene mutation as an early key event of cancer development; 2) considers the dose metric appropriate based on mode of action understanding; and 3) integrates the appropriate dose metric category with relevant exposure data to evaluate dose response options and cancer level of concern for the specified exposure scenario. Here, we test the framework with three demonstrated rodent carcinogens with varying human cancer assessments and underlying cancer biology: acrylamide, aflatoxin B1, and β-myrcene. While traditional cancer assessment approaches might characterize these chemicals as potential human carcinogens based primarily on rodent tumorigenicity data, the framework evaluates the cancer MOA in the context of exposure patterns to provide more information on conditions that may increase risk. We found that mutation is an early key event for aflatoxin B1 carcinogenicity, and linear low-dose extrapolation is an appropriate approach. In contrast, MOA data support a dose threshold-based approach for acrylamide and β-myrcene, and their respective dietary consumption patterns suggest a low concern for cancer. The framework provides a more nuanced approach to cancer risk assessment and provides for a more informed risk management decision.

Occurrence of regulated, emerging, and masked mycotoxins in Chinese wheat between 2021 and 2022

Wheat is one of three major food crops in China. Wheat grains are prone to contamination with various mycotoxins. The risk of exposure to mycotoxins through the consumption of wheat flour has long been a concern. This study evaluated the occurrence of regulated, marked, and emerging mycotoxins in 304 wheat samples that were randomly sampled from major wheat-producing regions of China. Aflatoxin B1 (AFB1) was detected in only 3 wheat samples, with a maximum concentration of 2.37 μg/kg. Deoxynivalenol (DON) was identified as the most prevalent mycotoxin, being present in 94.4 % of the samples with a maximum concentration of 2.84 mg/kg. Additionally, 11.5 % of the positive DON samples exceeded the maximum Chinese limit of 1000 μg/kg. The incidence of zearalenone (ZEN), zearalanone (ZAN), α-zearalenol, and β-zearalenol in wheat samples were 27.96, 2.96, 2.63, and 2.63 %, respectively. Of 304 wheat samples, 86.2 %, 14.5 and 7.24 % were positive for Deoxynivalenol-3-Glucoside (range: 3.58-609 μg/kg), 3-AcDON (range: 2.31-95.97 μg/kg), and 15-AcDON (range: 2.26-76.65 μg/kg), respectively. Beauvericin (BEA) was detected in 89.14 % of wheat samples with the maximum concentrations 114 μg/kg. However, the average concentration of BEA (2.40 μg/kg) in the positive samples was less than 10 μg/kg. Alternariol (AOH) and moniliformin were detected in 48.68 % and 16.78 % of wheat samples, respectively. Most wheat samples (89 %) were simultaneously contaminated with more than one mycotoxin, with an average of approximately five mycotoxins per sample, and up to 15 mycotoxins were detected in individual samples. In conclusion, DON was the most prevalent mycotoxin in wheat samples, followed by D-3-G, BEA, and AOH, and co-contamination of mycotoxins in wheat samples were very common.

Health risks evaluation of mycotoxins in plant-based supplements marketed in Malaysia

Mycotoxins are toxic secondary metabolites produced by fungi, pose significant health risks when present in plant-based supplements (PBS), necessitating thorough risk assessment to ensure consumer safety. This study evaluates the health risks associated with mycotoxins, specifically aflatoxins (AFB1, AFB2) and ochratoxin A (OTA), in PBS sold in Malaysia. Contamination levels of AFB1, AFB2, and OTA were quantified in 14 PBS samples using Liquid Chromatography-Mass Spectrometry. All samples tested positive for AFB2, while 28.57% and 42.86% tested positive for AFB1 and OTA, respectively with some levels exceeding the regulatory limits set by the Malaysian Food Act 1983 and European regulations. The estimated daily intake of these mycotoxins was calculated based on the recommended daily intake of each supplement. To assess risk, Margin of Exposure (MOE) values were determined, showing that all AFB2-positive samples had MOE values below the critical threshold of 10,000, indicating an urgent need for risk management. A quantitative cancer risk assessment also estimated the percentage of hepatocellular carcinoma and kidney cancer attributable to mycotoxin exposure. The findings emphasize the significant public health risks posed by mycotoxins, particularly in samples B2 and B10, where all three mycotoxins studied were present at concerning levels. This study highlights the urgent need for stricter regulations and better monitoring of mycotoxin levels in PBS to protect consumer's health.

The impact of small food workshops management regulations on aflatoxin B1 in home-made peanut oil and the liver function of high-consumption area residents: an interrupted time series study in Guangzhou, China

Background

Aflatoxin B1 (AFB1), a potent carcinogen produced by Aspergillus species, is a prevalent contaminant in oil crops, with prolonged exposure associated with liver damage. Home-made peanut oil (HMPO) produced by small workshops in Guangzhou is heavily contaminated with AFB1. Despite the enactment of the Small Food Workshops Management Regulations (SFWMR), no quantitative assessment has been conducted regarding its impact on food contamination and public health. The study aims to assess the impact of SFWMR on AFB1 contamination in HMPO and liver function in the population.

Method

AFB1 contamination in HMPO were quantified using high-performance liquid chromatography and liver function data were obtained from the health center located in a high-HMPO-consumption area in Guangzhou. Interrupted time series and mediation analyses were employed to assess the relationship between the implementation of SFWMR, AFB1 concentrations in HMPO, and liver function among residents.

Result

The AFB1 concentrations in HMPO were 1.29 (0.12, 6.58) μg/kg. The average daily intake of AFB1 through HMPO for Guangzhou residents from 2010 to 2022 ranged from 0.25 to 1.68 ng/kg bw/d, and the Margin of Exposure ranged from 238 to 1,600. The implementation of SFWMR was associated with a significant reduction in AFB1 concentrations in HMPO, showing an immediate decrease of 2.865 μg/kg (P = 0.006) and a sustained annual reduction of 2.593 μg/kg (P = 0.034). Among residents in the high-HMPO-consumption area, the implementation of SFWMR was significantly associated with a reduction in the prevalence of liver function abnormality (PR = 0.650, 95% CI: 0.469-0.902). Subgroup analysis revealed that this reduction was significantly associated with the implementation of SFWMR in the female (PR = 0.484, 95% CI: 0.310-0.755) and in individuals aged ≥ 60 years (PR = 0.586, 95% CI: 0.395-0.868). Mediation analysis demonstrated that AFB1 concentrations in HMPO fully mediated the relationship between the implementation of SFWMR and the liver function abnormality (PR = 0.981, 95% CI: 0.969-0.993).

Conclusion

In Guangzhou, the public health issue arising from AFB1 intake through HMPO warrants attention. The implementation of SFWMR had a positive impact on the improvement of AFB1 contamination in HMPO and the liver function. Continued efforts are necessary to strengthen the enforcement of the regulations. The exposure risks to AFB1 among high-HMPO-consumption groups also demand greater focus.

Simultaneous detection of multiple mycotoxins in Radix Dipsaci and estimation of exposure risk for consumers

Like many traditional Chinese herbal medicines, preparations from Radix Dipsaci are at risk of contamination by harmful mycotoxins; however, there have been no reports of actual contamination. In this study, we developed an analytical method to simultaneously detect eight mycotoxins in Radix Dipsaci and estimate the exposure risk for consumers. We have developed an analytical method utilizing ultra-high performance liquid chromatography and tandem mass spectrometry to accurately determine the levels of AFB1, AFB2, AFG1, AFG2, OTA, ZEN, T-2 and ST mycotoxins in 45 batches of Radix Dipsaci sourced from major medicinal herb markets across five regions in China. We also analyzed migration of mycotoxins from the raw herbs into water decoction. Based on these results and data on human consumption of the herbal medicine, we estimated risk of exposure and acceptable exposure limits to mycotoxins in the Radix Dipsaci using the "margin of exposure (MOE)" method. Of the 45 batches of Radix Dipsaci, 48.89% contained at least one of the eight mycotoxins, 24.44% contained one, 17.78% contained two and 6.67% contained three. The most frequent mycotoxins were aflatoxin B1, present in 35.56% of batches (at 0.25-34.84 μg/kg); aflatoxin G1, 15.56% (1.99-44.05 μg/kg); and ochratoxin A, 22.22% (16.11-143.38 μg/kg). These three mycotoxins transferred from the raw herb into water decoction at respective rates of 20.20%, 29.14%, and 24.80%. The 95th percentile values of the MOE risk factors for health effects of AFB1 were below 10,000 at high doses but above 10,000 at low doses of Radix Dipsaci long-term treatment. With the reduction in duration of exposure years, the MOE values of AFB1 and AFG1 gradually reverted to within the acceptable range. The mean, 50th, and 95th percentile values of the MOE risk factors for health effects of OTA exceeded 10,000 regardless of whether consumers received a low or high dose of Radix Dipsaci treatment for durations ranging from 1 to lifetime. Based on this exposure and a typical human diet, we have estimated the respective 20-year exposure limits for Radix Dipsaci to be 5.821 μg/kg, 4.035 μg/kg, and 56.073 μg/kg for the three mycotoxins under consideration. Contamination with multiple mycotoxins is frequently observed in Radix Dipsaci, and the three most prevalent contaminants have been found to leach into water decoctions, thereby posing a potential health hazard for individuals consuming this herbal preparation. This work highlights the need to monitor herbal medicines for mycotoxin contamination in order to protect consumers.

Aflatoxin M1 levels in urine and breast milk of lactating mothers in Kuala Lumpur, Malaysia

Aflatoxins are carcinogens that can contaminate food and affect various body organs especially liver and kidney. When consumed, aflatoxin B1 (AFB1) is partially metabolised into aflatoxin M1 (AFM1), which is excreted in the urine. Breast milk may also contain AFM1 due to maternal dietary intake from contaminated food. This cross-sectional study aimed to determine the levels of AFM1 in both urine and breast milk among breastfeeding mothers (n = 256). The mother's demographic information was collected during recruitment. Mothers were then scheduled for an appointment to provide a morning urine sample along with five to ten mL samples of breast milk. AFM1 levels in both samples were analysed using an enzyme-linked immunosorbent assay (ELISA). Spearman's rho and Chi-square were used to determine the associations between mean levels of AFM1 in urine and breast milk. Findings show 68.0% of urine samples were contaminated with AFM1 (mean levels = 0.08 ± 0.04 ng/mL), while 14.8% of breast milk samples had AFM1 (mean levels = 5.94 ± 1.81 ng/kg). Urine AFM1 levels were not significantly associated with AFM1 levels in breast milk (p > 0.05). This study can act as a baseline for future research examining long-term aflatoxin exposure among both mothers and infants.

Aflatoxin B1-induced liver pyroptosis is mediated by disturbing the gut microbial metabolites: The roles of pipecolic acid and norepinephrine

The disturbed gut microbiota is a key factor in activating the aflatoxin B1 (AFB1)-induced liver pyroptosis by promoting inflammatory hepatic injury; however, the pathogen associated molecular pattern (PAMP) from disturbed gut microbiota and its mechanism in activating liver pyroptosis remain undefined. By transplanting AFB1-originated fecal microbiota and sterile fecal microbial metabolites filtrate, we determined the association of PAMP in AFB1-induced liver pyroptosis. Notably, AFB1-originated sterile fecal microbial metabolites filtrate were more active in triggering liver pyroptosis in mice, as compared to parental fecal microbiota. This result supported a critical role of the metabolic homeostasis of gut microbiota in AFB1-induced liver pyroptosis, rather than an injurious response to direct exposure of AFB1 in liver. Among the gut-microbial metabolites, pipecolic acid and norepinephrine were proposed to bind TLR4 and NLRP3, the upstream proteins of pyroptosis signaling pathway. Besides, the activations of TLR4 and NLRP3 were linearly correlated with the concentrations of pipecolic acid and norepinephrine in the serum of mice. In silenced expression of TLR4 and NLRP3 in HepG2 cells, pipecolic acid or norepinephrine did not able to activate hepatocyte pyroptosis. These results demonstrated the necessity of gut microbial metabolism in sustaining liver homeostasis, as well as the potential to provide new insights into targeted intervention for AFB1 hepatotoxicity.

The potential for reducing aflatoxin B1 contamination of stored peanuts by soil disinfection

Aflatoxins from the fungus Aspergillus flavus (A. flavus) that contaminate stored peanuts is a major hazard to human health worldwide. Reducing A. flavus in soil can decrease the risk of aflatoxins in stored peanuts. In this experiment, we determined whether peanuts grown on soil fumigated with dazomet (DZ), metham sodium (MS), allyl isothiocyanate (AITC), chloropicrin (PIC) or dimethyl disulfide (DMDS) would reduce of the quantity of A. flavus and its toxin's presence. The results of bioassays and field tests showed that PIC was the most effective fumigant for preventing and controlling A. flavus, followed by MS. PIC and MS applied to the soil for 14 d resulted in LD50 values against A. flavus of 3.558 and 4.893 mg kg-1, respectively, leading to almost 100% and 98.82% effectiveness of A. flavus, respectively. Peanuts harvested from fumigated soil and then stored for 60 d resulted in undetectable levels of aflatoxin B1 (AFB1) compared to unfumigated soil that contained 0.64 ug kg-1 of AFB1, which suggested that soil fumigation can reduce the probability of aflatoxin contamination during peanut storage and showed the potential to increase the safety of peanuts consumed by humans. Further research is planned to determine the practical value of our research in commercial practice.

Aflatoxin B1 exposure causes splenic pyroptosis by disturbing the gut microbiota-immune axis

Aflatoxin B1 (AFB1) causes serious immunotoxicity and has attracted considerable attention owing to its high sensitivity and common chemical-viral interactions in living organisms. However, the sensitivity of different species to AFB1 widely varies, which cannot be explained by the different metabolism in species. The gut microbiota plays a crucial role in the immune system, but the interaction of the microbiota with AFB1-induced immunotoxicity still needs to be determined. Our results indicated that AFB1 exposure disrupted the structure of the gut microbiota and damaged the gut barrier, which caused translocation of microbiota metabolites, lipopolysaccharides, to the spleen. Subsequently, pyroptosis of the spleen was activated. Interestingly, AFB1 exposure had little effect on the splenic pyroptosis of pseudo-germfree mice (antibiotic mixtures eliminated their gut microbiota, ABX). Then, fecal microbiota transplant (FMT) and sterile fecal filtrate (SFF) were employed to validate the function of the gut microbiota and its metabolites in AFB1-induced splenic pyroptosis. The AFB1-disrupted microbiota and its metabolites significantly promoted splenic pyroptosis, which was worse than that in control mice. Overall, AFB1-induced splenic pyroptosis is associated with the gut microbiota and its metabolites, which was further demonstrated by FMT and SFF. The mechanism of AFB1-induced splenic pyroptosis was explored for the first time, which paves a new way for preventing and treating the immunotoxicity from mycotoxins by regulating the gut microbiota.

Determination and risk assessment of aflatoxin B1 in the kernel of imported raw hazelnuts from Eastern Azerbaijan Province of Iran

Aflatoxin B1 (AFB1) is widespread and seriously threatens public health worldwide. This study aimed to investigate AFB1 in imported hazelnut samples in northwest of Iran (Eastern Azerbaijan Province) using High-Performance Liquid Chromatography with a Fluorescent Detector (HPLC-FLD). In all tested samples AFB1 was detected. The mean concentration of AFB1 was 4.20 μg/kg and ranged from 3.145 to 8.13 μg/kg. All samples contained AFB1 levels within the maximum acceptable limit except for one sample. Furthermore, the human health risk assessment of AFB1 from consuming imported hazelnuts by Iranian children and adults was evaluated based on the margin of exposure (MoE) and quantitative liver cancer risk approaches. The MoE mean for children was 2529.76, while for adults, it was 8854.16, indicating a public health concern. The present study found that the risk of developing liver cancer among Iranian children was 0.11100736 per 100,000 people, and in the Iranian adult population was 0.0314496 cancers per 100,000 people. Since environmental conditions potentially affect aflatoxin levels in nuts, countries are advised to monitor aflatoxin contents in imported nuts, especially from countries with a conducive climate for mold growth.

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.

Assessment of the Adverse Health Effects of Aflatoxin Exposure from Unpackaged Peanut Oil in Guangdong, China

Aflatoxins are liver carcinogens and are common contaminants in unpackaged peanut (UPP) oil. However, the health risks associated with consuming aflatoxins in UPP oil remain unclear. In this study, aflatoxin contamination in 143 UPP oil samples from Guangdong Province were assessed via liquid chromatography-tandem mass spectrometry (LC-MS). We also recruited 168 human subjects, who consumed this oil, to measure their liver functions and lipid metabolism status. Aflatoxin B1 (AFB1) was detected in 79.72% of the UPP oil samples, with levels ranging from 0.02 to 174.13 μg/kg. The average daily human intake of AFB1 from UPP oil was 3.14 ng/kg·bw/day; therefore, the incidence of liver cancer, caused by intake of 1 ng/kg·bw/day AFB1, was estimated to be 5.32 cases out of every 100,000 persons per year. Meanwhile, Hepatitis B virus (HBV) infection and AFB1 exposure exerted a synergistic effect to cause liver dysfunction. In addition, the triglycerides (TG) abnormal rate was statistically significant when using AFB1 to estimate daily intake (EDI) quartile spacing grouping (p = 0.011). In conclusion, high aflatoxin exposure may exacerbate the harmful effects of HBV infection on liver function. Contamination of UPP oil with aflatoxins in Guangdong urgently requires more attention, and public health management of the consumer population is urgently required.

Dietary exposure to zearalenone in maize and millet grains and their porridges marketed in Abidjan (Côte d'Ivoire)

Maize and millet are among the staple foods of sub-Saharan populations. In Côte d'Ivoire, maize and millet are, respectively, second and third most consumed cereals. In this work, we evaluate the health risk related to the presence of zearalenone in maize and millet and their porridges. The zearalenone contents of the foodstuffs were determined using HPLC-UV. The health risk was characterised by the ratio (R) of probable daily intake (PDI) to acceptable daily intake (ADI). The consumption of maize generates a significant health risk in infants (R = 163.4%). Likewise, millet contains excess zearalenone for infants and children with R = 2934.0% and 118.0%, respectively. The combination of maize and millet increases the risk for infants (R = 457.4%), children (R = 183.0%) and adolescents (R = 101.6%). Millet porridge caused a significant health risk in infants (R = 120%). Consumption of the two types of porridge significantly increases the health risk. Thus, the R ratio varies between 48% and 444% in the case of ingestion of both types of porridge, against 12-56% for maize porridge, and 24-120% for millet porridge. Children and infants were most exposed with respective R of 120% and 444%. These results suggest a need for vigilance to minimise exposure to zearalenone.

Aflatoxin B1 Induces Inflammatory Liver Injury via Gut Microbiota in Mice

Aflatoxin B₁ (AFB₁), a potent food-borne hepatocarcinogen, is the most toxic aflatoxin that induces liver injury in humans and animals. Species-specific sensitivities of aflatoxins cannot be fully explained by differences in the metabolism of AFB₁ between animal species. The gut microbiota are critical in inflammatory liver injury, but it remains to reveal the role of gut microbiota in AFB₁-induced liver injury. Here, mice were gavaged with AFB₁ for 28 days. Then, the modulation of gut microbiota, colonic barrier, and liver pyroptosis and inflammation were analyzed. To further verify the direct role of gut microbiota in AFB₁-induced liver injury, mice were treated with antibiotic mixtures (ABXs) to deplete the microbiota, and fecal microbiota transplantation (FMT) was conducted. The treatment of AFB₁ in mice altered gut microbiota composition, such as increasing the relative abundance of Bacteroides, Parabacteroides, and Lactobacillus, inducing colonic barrier dysfunction and promoting liver pyroptosis. In ABX-treated mice, AFB₁ had little effect on the colonic barrier and liver pyroptosis. Notably, after FMT, in which the mice were colonized with gut microbiota from AFB₁-treated mice, colonic barrier dysfunction, and liver pyroptosis and inflammation were obliviously identified. We proposed that the gut microbiota directly participated in AFB₁-induced liver pyroptosis and inflammation. These results provide new insights into the mechanisms of AFB₁ hepatotoxicity and pave a window for new targeted interventions to prevent or reduce AFB₁ hepatotoxicity.

Food aflatoxin exposure assessment in Sichuan Province, China

Aflatoxins (AFs) are frequent contaminants in crops worldwide and can cause adverse health effects in exposed humans. Since foods AFs (AFB₁, AFB₂, AFG₁, AFG₂) contamination in Sichuan Province are unexplored, we conducted a study to assess AFs exposure in the population. In total, 318 samples, including grains, red chilli, red chilli powder, and vegetable protein beverages, were collected from 13 cities of Sichuan Province, China, in 2022. AFs were detected in all types of foods except for wheat flour, the highest incidence was found in red chilli powder (75.0%). The concentrations of AF_tot (the total aflatoxins) ranged between ND (not detected) and 54.20 μg kg^-1. It was observed that the AFs profile was dominated by AFB₁. The AFB₁ content ranged from ND to 52.60 μg kg^-1 across food types. According to EU maximum limits (ML) of AFs, 2.8% of samples exceeded the AF_tot limits. For AFB₁, 0.4% and 4.3% of samples exceeded the China and EU limits, respectively. In this study, packaging types and sampling sites were selected as parameters influence food aflatoxin contamination. Nevertheless, there was no significant difference between different samples. According to exposure assessment and risk characterization, AF_tot daily exposure was shown to be 0.263 and 283.936 ng kg^-1 bw for the lower and upper exposure. The MOE value derived from consumption grains and red chilli pepper products were generally bellow 10 000, and liver cancer cases based on these two foods consumption could range from < 0.001 to 0.16 cases per year/10 000 persons.

Contamination and Health Risk Assessment of Multiple Mycotoxins in Edible and Medicinal Plants

Edible and medicinal plants (EMPs) are widely used but are easily infected by harmful fungi which produce mycotoxins. Herein, 127 samples from 11 provinces were collected to investigate 15 mycotoxins based on geographic, demographic, processing, and risk characteristics. A total of 13 mycotoxins were detected, and aflatoxin B1 (0.56~97.00 μg/kg), deoxynivalenol (9.41~1570.35 μg/kg), fumonisin B1 (8.25~1875.77 μg/kg), fumonisin B2 (2.74~543.01 μg/kg), ochratoxin A (0.62~19.30 μg/kg), and zearalenone (1.64~2376.58 μg/kg) occurred more frequently. Mycotoxin levels and species were significantly different by region, types of EMPs, and method of processing. The margin of exposure (MOE) values was well below the safe MOE (10,000). AFB1 exposure from Coix seed and malt consumption in China was of high health concern. The hazard Index (HI) method showed the range of 113.15~130.73% for malt, indicating a public health concern. In conclusion, EMPs should be concerned because of the cumulative effects of co-occurred mycotoxins, and safety management strategies should be developed in follow-up studies.

Exposure assessment of aflatoxins and zearalenone in edible vegetable oils in Shandong, China: health risks posed by mycotoxin immunotoxicity and reproductive toxicity in children

Human exposure to aflatoxins (AFs) and zearalenone (ZEA) has not been sufficiently investigated. Here, we analyzed the exposure level and health risks posed by AFs (B1, B2, G1, G2) and ZEA through cooking oil consumption in Shandong, China. The individual daily consumption of cooking oil was calculated through 2745 questionnaires during 2017-2019. The average contamination levels of mycotoxins were estimated by examining 60 cooking oil samples. For the peanut oil, AFs ranged from <0.2 to 274 μg/kg, with a positive rate of 66.6% (20/30). Average levels of 36.62 μg/kg AFB₁ and 44.43 μg/kg total AFs were found. Over-the-limit level (20 μg/kg) of AFB₁ was detected in 8/30 samples. Estimated daily intake (EDI) and margin of exposure (MOE) for age-stratified population groups showed that children are facing highest adverse health risk with AFB₁ (MOE 5.88-6.39). The liver cancer incidences attributable to AFB₁ exposure are non-negligible as 0.896, 0.825, and 0.767 cases per 100,000 for 6-14 age group, 15-17 age group, and adult labor-intensive workers. Over-the-limit level (60 μg/kg) ZEA contamination was detected in 25/30 corn oil samples with a 50th percentile value of 97.95 μg/kg. Our health risk assessment suggested significant health risks of enterohepatic (inflammation and cancer), reproductive, and endocrine systems posed by AFs and ZEA. However, the health risk of immunotoxicity is unclear because currently animal study data are not available for the immunotoxicity induced after long-term exposure. In general, the health risks posed by mycotoxins are non-negligible and long-term mycotoxin surveillance is necessary.

Tracing the pollution and human risks of potentially toxic elements in agricultural area nearby the cyanide baths from an active private gold mine in Hainan Province, China

Mining activities are well-known sources of potentially toxic elements (PTEs) pollution, which often jeopardize the biosphere, pedosphere, and hydrosphere. However, the soil and groundwater pollution caused by active private mining activities has long been neglected. This study investigated the occurrence of PTEs and cyanide (CN) in agricultural soils, mine tailings, and groundwater nearby the cyanide baths from a private gold mine in Hainan Province, southern China. Results indicated that concentrations of Pb, As, Cd, Hg, and CN in different soil depths and mine tailings were up to ten thousand mg/kg, and relatively higher content of As and Pb was detected in groundwater. The chemical forms of Cd, Pb, As, and Hg varied greatly in different soil depths; over 80% of Cd distributed in the water-soluble fraction, suggesting its higher mobility in soils, while approximately 60-90% of Pb, As, and Hg distributed in other chemical fractions, indicating relatively lower mobility in soils. The pollution indices also revealed the serious pollution and deterioration of site quality in this area. Human risk assessments also reflected a high non-carcinogenic/carcinogenic health risk in this area. The framework of integrated management strategies for private metal mines was proposed to mitigate PTEs pollution and reduce health risks.

Risk Assessment of Hepatocellular Carcinoma with Aflatoxin B1 Exposure in Edible Oils

Contamination of edible oils with aflatoxins (AFs) is a universal issue due to the detrimental effects of aflatoxins on human health and the fact that edible oils are a major source of fungal growth, particularly storage fungi (Aspergillus sp.). The objective of this study was to assess aflatoxin B1 (AFB1) in edible oil used in fried food in order to determine the risk of cancer from AFB1 exposure through cooked food using the FAO/WHO’s and EFSA’s margin of exposure (MOE) quantitative liver cancer risk approaches. Using Mycosep 226 columns and HPLC-FLD, 100 samples of cooking oils (soybean, canola, and sunflower oil) from different food points were analyzed for contamination with aflatoxins. Of all the samples tested, 89% were positive for total aflatoxins and AFB1, with 65% indicating AF concentrations beyond permitted levels. Canola oil was found to contain higher levels of AFB1 and AFs than soybean and sunflower oil. Almost 71 percent of canola oil samples (range of 54.4–281.1 µg/kg) were contaminated with AF levels higher than the proposed limits of the European Union (20 µg/kg). The consumption of canola oil samples used in fried foods had MOE values that were significantly lower as compared to sunflower and soybean oils, indicating that risk reduction is feasible. Additionally, compared to soybean and sunflower oil, canola oil exhibited a greater threat of liver cancer cases linked to AFB1 exposure (17.13 per 100,000 males over 35 and 10.93 per 100,000 females over 35). Using a quantitative liver cancer approach, health risk valuation demonstrated that males and females over the age of 35 are at significant risk of developing liver cancer. The health risk assessment exposed that the males and female over the age of 35 are at considerable risk of liver cancer by using a quantitative liver cancer approach. The innovation of this study lies in the fact that no such study is reported related to liver cancer risk evaluation accompanied with AFB1 exposure from consumed edible oil. As a result, a national strategy must be developed to solve this problem so that edible oil products are subjected to severe regulatory examination.

Multi-Mycotoxin Contamination, Mold Incidence and Risk Assessment of Aflatoxin in Maize Kernels Originating from Nepal

Occurrence of mycotoxins in staple foods is a major threat to attaining food safety in developing countries. The study investigated multi-mycotoxin contamination for the first time in Nepalese maize along with the incidence of molds in 45 samples of maize used as human food from 45 districts of Nepal. The samples were analyzed quantitatively for the presence of five different mycotoxins (total aflatoxins (AF), total fumonisins (FUM), ochratoxin (OT), zearalenone (ZEA) and (DON) deoxynivalenol) using the competitive direct ELISA technique. The most frequent occurrences were for DON (100%) and AF (78%) followed by FUM and ZEA (both 76%) and OT (62%). Interestingly, all the samples contained at least two mycotoxins while at least three or more mycotoxins were found in 87% of the samples. The most commonly reported binary, ternary and quaternary combinations were DON+AF, AF+FUM+DON and AF+FUM+ZEA+DON, respectively. The mean percentage kernel mold infection was 35.33% with Fusarium, Aspergillus, Rhizopus and Penicillium genera being the predominant molds. Six different species of Aspergillus and a single species of Fusarium were identified. The estimated daily intake, margin of exposure and risk of liver cancer from consuming maize were 30.46 ng/kg bw/day and 5.58 and 0.38 cancer cases/year/100,000 population, respectively. Since maize is the second-most consumed cereal in Nepal, the contamination levels of various mycotoxins and the incidence of molds identified in the study suggests that stricter control is needed to safeguard the health of the substantial population consuming maize as a staple diet.

Dietary Exposure and Risk Assessment of Mycotoxins in Thyme and Thyme-Based Products Marketed in Lebanon

This study aimed at evaluating the incidence of aflatoxin B1 (AFB1) and ochratoxin A (OTA) in thyme and thyme-based products, related dietary exposure, and cancer risk for regular and high consumption. A total of 160 samples were collected, and 32 composite samples were analyzed. AFB1 and OTA were respectively found in 84% (27/32) and 38% (12/32) of the samples. AFB1 exceeded the limits in 41% (13/32) and 25% (8/32) of the samples according to the Lebanese and European standards, respectively. OTA was unacceptable in only 6% (2/32) and 3% (1/32) of the samples according to the Lebanese and European standards, respectively. AFB1 and OTA daily exposure was shown to be 4.270 and 1.345 ng/kg bw/day, respectively. AFB1 was shown to be associated with 0.41 and 0.35 additional cancer cases per 100,000 persons per year for regular consumption, respectively; while for high consumption, an increase of 0.911 and 0.639 cancer cases per 100,000 person per year was noted, respectively. The margin of exposure (MOE) for OTA was >10,000 for the non-neoplastic effect and >200 for the neoplastic effect, representing no toxicological concerns for consumers.

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.

Detection and Localization of Solid Tumors Utilizing the Cancer-Type-Specific Mutational Signatures

Accurate detection and location of tumor lesions are essential for improving the diagnosis and personalized cancer therapy. However, the diagnosis of lesions with fuzzy histology is mainly dependent on experiences and with low accuracy and efficiency. Here, we developed a logistic regression model based on mutational signatures (MS) for each cancer type to trace the tumor origin. We observed MS could distinguish cancer from inflammation and healthy individuals. By collecting extensive datasets of samples from ten tumor types in the training cohort (5,001 samples) and independent testing cohort (2,580 samples), cancer-type-specific MS patterns (CTS-MS) were identified and had a robust performance in distinguishing different types of primary and metastatic solid tumors (AUC:0.76 ∼ 0.93). Moreover, we validated our model in an Asian population and found that the AUC of our model in predicting the tumor origin of the Asian population was higher than 0.7. The metastatic tumor lesions inherited the MS pattern of the primary tumor, suggesting the capability of MS in identifying the tissue-of-origin for metastatic cancers. Furthermore, we distinguished breast cancer and prostate cancer with 90% accuracy by combining somatic mutations and CTS-MS from cfDNA, indicating that the CTS-MS could improve the accuracy of cancer-type prediction by cfDNA. In summary, our study demonstrated that MS was a novel reliable biomarker for diagnosing solid tumors and provided new insights into predicting tissue-of-origin.

Automated Paper-Based Femtogram Sensing Device for Competitive Enzyme-Linked Immunosorbent Assay of Aflatoxin B1 Using Submicroliter Samples

Microfluidic paper-based analytical devices (μPADs) are promising biosensors that may be used in a variety of bioanalytical applications. A μPAD for automating the competitive enzyme-linked immunosorbent assay (ELISA) of small-sized target detection at the femtogram level using submicroliter samples is reported in this study. The proposed μPAD was integrated with a sucrose valve to automate the sequential delivery of reagents, providing simple control of reagent delivery time and simple operation. The use of a sample solution dropping location at the zones on the device that had been prepared with an antibody-conjugated enzyme before immersion in a running buffer allowed minimization of sample volume to 0.6 μL, while eliminating the possible loss of a target molecule by adsorption on the membrane, thus improving detection sensitivity. Furthermore, the proposed device was successfully applied to the automation of competitive ELISA for the detection of aflatoxin B₁ (AFB₁), a potent carcinogen that causes substantial health risks to humans worldwide, with a detection limit of 60 femtograms or 0.1 ng/mL. The method developed in this study provides high sensitivity, small sample volume, on-site and equipment-free measurements, low-cost operation, and user-friendliness. This approach could be used to analyze small-sized molecules in the fields of food safety and quality control, environmental monitoring, and clinical diagnostics.

The aflatoxin B1 content of peanut-based foods in Iran: a systematic review

BACKGROUNDS

One of the common consumed snacks among Iranian is nuts. The aim of this systematic review was to determine the rate of peanut contamination with aflatoxin B1 (AfB1) in different provinces of the Iran.

MATERIALS AND METHODS

The research studies with keywords "aflatoxin B1", "peanut", "peanut butter", "peanut oil", "coated peanut", "roasted peanut", "snack peanut" were searched in PubMed, Scopus, Science Direct, Google Scholar and scientific information databases (SID), regardless of publication time. A total of 43 studies were obtained and only six articles were finally selected according to exclusion and inclusion criteria. Margin of Exposure (MOE) and Hazard Quotient (HQ) were also calculated to evaluate the oral exposure of AfB1 through peanuts and peanut-based products.

RESULTS

The contamination of AFB1 in peanut was high in Mashhad and Tehran compared with the other cities. The value of MOE was calculated less than 10,000. The results of MOE indicate that there are chances of the risk of developing cancer and these products may not be safe. Therefore, AFB1 levels should be measured regularly in peanut products in large cities.

Burden of Disease Associated with Dietary Exposure to Aflatoxins in China in 2020

Aflatoxins (AFTs), as a group 1 carcinogen, could lead to hepatocellular carcinoma (HCC). Dietary intake is the primary way of AFT exposure in humans. However, the contribution of foodborne AFT intake to the HCC burden remains unknown in recent years in China. Hence, the present study was conducted to estimate the burden of HCC attributed to foodborne AFT exposure by using disability-adjusted life years (DALYs). The risk assessment was used to estimate the incidence of HCC related to AFT exposure. Concentrations of AFTs in peanuts, peanut oil, corn, and corn products were retrieved from literature published between 2010 and 2020 in China. Corresponding daily food consumption data were obtained from two nationwide Chinese surveys. A direct approach was used to calculate DALY and DALY rates to quantify the HCC burden attributed to dietary AFT exposure. The total amount of AFT intake through peanut, peanut oil, corn, and corn products was 4.018 ng/kg bw/day resulting in 0.125 extra HCC cases per year/100,000 persons, corresponding to a DALY number and DALY rate of 21,625.08 and 1.53 per 100,000 population, respectively. Regionally, DALYs were high in Guangxi and Guangdong provinces, corresponding to 5948 and 5595 DALYs. A total of 1.5 DALYs/100,000 were lost due to the AFT exposure. DALYs per 100,000 population were higher in several coastal areas. Though the disease burden of HCC caused by dietary AFTs was low in the Chinese population, a high health risk was found in the residents of some areas with high AFT exposure. AFTs are still a health challenge for the Chinese people.

Food-Grade Expression of Manganese Peroxidases in Recombinant Kluyveromyces lactis and Degradation of Aflatoxin B1 Using Fermentation Supernatants

Aflatoxins are naturally occurring high-toxic secondary metabolites, which cause worldwide environmental contaminations and wastes of food and feed resources and severely threaten human health. Thus, the highly efficient methods and technologies for detoxification of aflatoxins are urgently needed in a long term. In this work, we report the construction of recombinant Kluyveromyces lactis strains GG799(pKLAC1-Phsmnp), GG799(pKLAC1-Plomnp), GG799(pKLAC1-Phcmnp), and then the food-grade expression of the three manganese peroxidases in these strains, followed by the degradation of aflatoxin B1 (AFB1) using the fermentation supernatants. The expression of the manganese peroxidases was achieved in a food-grade manner since Kluyveromyces lactis is food-safe and suitable for application in food or feed industries. The inducible expression process of the optimal recombinant strain GG799(pKLAC1-Phcmnp) and the aflatoxin B1 degradation process were both optimized in detail. After optimization, the degradation ratio reached 75.71%, which was an increase of 49.86% compared to the unoptimized results. The degradation product was analyzed and determined to be AFB1-8,9-dihydrodiol. The recombinant strain GG799(pKLAC1-Phcmnp) supernatants degraded more than 90% of AFB1 in the peanut samples after twice treatments. The structural computational analysis for further mutagenesis of the enzyme PhcMnp was also conducted in this work. The food-grade recombinant yeast strain and the enzyme PhcMnp have potential to be applied in food or feed industries.

Preparation of an Immunoaffinity Column Based on Bispecific Monoclonal Antibody for Aflatoxin B1 and Ochratoxin A Detection Combined with ic-ELISA

A novel and efficient immunoaffinity column (IAC) based on bispecific monoclonal antibody (BsMAb) recognizing aflatoxin B₁ (AFB₁) and ochratoxin A (OTA) was prepared and applied in simultaneous extraction of AFB₁ and OTA from food samples and detection of AFB₁/OTA combined with ic-ELISA (indirect competitive ELISA). Two deficient cell lines, hypoxanthine guanine phosphoribosyl-transferase (HGPRT) deficient anti-AFB₁ hybridoma cell line and thymidine kinase (TK) deficient anti-OTA hybridoma cell line, were fused to generate a hybrid-hybridoma producing BsMAb against AFB₁ and OTA. The subtype of the BsMAb was IgG₁ via mouse antibody isotyping kit test. The purity and molecular weight of BsMAb were confirmed by SDS-PAGE method. The cross-reaction rate with AFB₂ was 37%, with AFG₁ 15%, with AFM₁ 48%, with AFM₂ 10%, and with OTB 36%. Negligible cross-reaction was observed with other tested compounds. The affinity constant (Ka) was determined by ELISA. The Ka (AFB₁) and Ka (OTA) was 2.43 × 10⁸ L/mol and 1.57 × 10⁸ L/mol, respectively. Then the anti-AFB₁/OTA BsMAb was coupled with CNBr-Sepharose, and an AFB₁/OTA IAC was prepared. The coupling time and elution conditions of IAC were optimized. The coupling time was 1 h with 90% coupling rate, the eluent was methanol–water (60:40, v:v, pH 2.3) containing 1 mol/L NaCl, and the eluent volume was 4 mL. The column capacities of AFB₁ and OTA were 165.0 ng and 171.3 ng, respectively. After seven times of repeated use, the preservation rates of column capacity for AFB₁ and OTA were 69.3% and 68.0%, respectively. The ic-ELISA for AFB₁ and OTA were applied combined with IAC. The IC₅₀ (50% inhibiting concentration) of AFB₁ was 0.027 ng/mL, the limit of detection (LOD) was 0.004 ng/mL (0.032 µg/kg), and the linear range was 0.006 ng/mL~0.119 ng/mL. The IC₅₀ of OTA was 0.878 ng/mL, the LOD was 0.126 ng/mL (1.008 µg/kg), and the linear range was 0.259 ng/mL~6.178 ng/mL. Under optimum conditions, corn and wheat samples were pretreated with AFB₁-OTA IAC. The recovery rates of AFB₁ and OTA were 95.4%~105.0% with ic-ELISA, and the correlations between the detection results and LC-MS were above 0.9. The developed IAC combined with ic-ELISA is reliable and could be applied to the detection of AFB₁ and OTA in grains.

Synthesis of Rice Husk-Based MCM-41 for Removal of Aflatoxin B1 from Peanut Oil

Edible oils, especially peanut oil, usually contain aflatoxin B₁ (AFB₁) at extremely high concentrations. This study focused on the synthesis of rice husk-based mesoporous silica (MCM-41) for the removal of AFB₁ from peanut oil. MCM-41 was characterized by X-ray diffraction, N₂ physisorption, and transmission electron microscope. MCM-41 was shown to have ordered channels with high specific surface area (1246 m²/g), pore volume (1.75 cm³/g), and pore diameter (3.11 nm). Under the optimal concentration of 1.0 mg/mL of the adsorbent dose, the adsorption behavior of MCM-41, natural montmorillonite (MONT), and commercial activated carbon (CA) for AFB₁ were compared. The adsorption of AFB₁ in peanut oil onto the three adsorbents was slower compared to that of AFB₁ in an aqueous solution. In addition, the pseudo-second-order kinetic model better fit the adsorption kinetics of AFB_1, while the adsorption mechanism followed the Langmuir adsorption isotherm on the three adsorbents. The calculated maximum adsorbed amounts of AFB₁ on MONT, MCM-41, and CA were 199.41, 215.93, and 248.93 ng/mg, respectively. These results suggested that MCM-41 without modification could meet market demand and could be considered a good candidate for the removal of AFB₁ from peanut oil. This study provides insights that could prove to be of economic and practical value.

Effects of Prenatal Exposure to Aflatoxin B1: A Review

Aflatoxins are mycotoxins produced as secondary fungal metabolites. Among them, aflatoxin B1 (AFB1) stands out due to its genotoxic and mutagenic potential, being a potent initiator of carcinogenesis. In this review, the outcomes from the published literature in the past 10 years on the effects of AFB1 pathophysiological mechanisms on embryological and fetal development are discussed. In several animal species, including humans, AFB1 has a teratogenic effect_, resulting in bone malformations, visceral anomalies, lesions in several organs, and behavioral and reproductive changes, in addition to low birth weight. The mutagenic capacity of AFB1 in prenatal life is greater than in adults, indicating that when exposure occurs in the womb, the risk of the development of neoplasms is higher. Studies conducted in humans indicate that the exposure to this mycotoxin during pregnancy is associated with low birth weight, decreased head circumference, and DNA hypermethylation. However, as the actual impacts on humans are still unclear, the importance of this issue cannot be overemphasized and studies on the matter are essential.

Exposure and risk characterizations of ochratoxins A and aflatoxins through maize (Zea mays) consumed in different agro-ecological zones of Ghana

Mycotoxin contamination of foodstuffs is a serious food safety concern globally as the prolonged ingestion of these toxins has the tendency to worsen the risk of hepatocellular carcinoma. This study aimed at estimating ochratoxin A (OTA) and aflatoxin (AF) levels above international (European Food Safety Authority, EFSA) and local (Ghana Standards Authority, GSA) standards as well as the health risks associated with the consumption of maize (n = 180) sampled from six (6) regions representing the agro-ecological zones of Ghana. OTA and AF were measured with High-Performance Liquid Chromatography with a Fluorescence detector. Out of the 180 samples analyzed for total aflatoxins (AFtotal), 131/180 tested positive and 127 (70.50%) exceeded the limits of EFSA and ranged 4.27-441.02 µg/kg. While for GSA, 116 (64.44%) of samples exceeded this limit and ranged between 10.18 and 441.02 µg/kg. For OTA, 103/180 tested positive and 94 (52.22%) of samples between the range 4.00-97.51 µg/kg exceeded the tolerable limit of EFSA, whereas 89 (49.44%) and were in the range of 3.30-97.51 µg/kg exceeded the limits of GSA. Risk assessment values for total aflatoxins (AFtotal) ranged between 50 and 1150 ng/kg bw/day, 0.4-6.67, 0-0.0323 aflatoxins ng/kg bw/day and 1.62-37.15 cases/100,000 person/year for Estimated Daily Intake (EDI), Margin of Exposure (MOE), Average Potency, and Cancer Risks respectively. Likewise, ochratoxin (OTA) values were in the ranges of 8.6 × 10-3-450 ng/kg bw/day, 0.05-2059.97, 0-0.0323 ochratoxins ng/kg bw/day and 2.78 × 10-4-14.54 cases/100,000 person/year. Consumption of maize posed adverse health effects in all age categories of the locations studied since the calculated MOE values were less than 10,000.

Distribution of Aspergillus Fungi and Recent Aflatoxin Reports, Health Risks, and Advances in Developments of Biological Mitigation Strategies in China

Aflatoxins (AFs) are secondary metabolites that represent serious threats to human and animal health. They are mainly produced by strains of the saprophytic fungus Aspergillus flavus, which are abundantly distributed across agricultural commodities. AF contamination is receiving increasing attention by researchers, food producers, and policy makers in China, and several interesting review papers have been published, that mainly focused on occurrences of AFs in agricultural commodities in China. The goal of this review is to provide a wider scale and up-to-date overview of AF occurrences in different agricultural products and of the distribution of A. flavus across different food and feed categories and in Chinese traditional herbal medicines in China, for the period 2000-2020. We also highlight the health impacts of chronic dietary AF exposure, the recent advances in biological AF mitigation strategies in China, and recent Chinese AF standards.

Down-regulation of microRNA-125b-2-3p is a risk factor for a poor prognosis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a leading cause of mortality in cancer patients, but the association between miR-125b-2-3p and the onset and prognosis of HCC has not been reported in previous studies; thus, the clinicopathological implications of miR-125b-2-3p in HCC require elaboration. To examine the expression of miR-125b-2-3p in HCC, both in-house RT-qPCR and public datasets were used to calculate the standard mean difference (SMD) and the summary receiver operating characteristic (sROC). MiR-125b-2-3p was markedly lower in HCC than in non-tumor tissue as assessed by the in-house RT-qPCR which was confirmed by the integrative analysis showing the SMD being -0.69 and the area under the curve (AUC) being 0.84 based on 1,233 cases of HCC and 630 cases of non-HCC controls. To gain a overview of the clinical value of miR-125b-2-3p in HCC, all possible datasets were integrated, and lower miR-125b-2-3p levels could lead to poorer differentiation and a more advanced clinical stage of HCC. The hazard ratio (HR) of miR-125b-2-3p was also calculated using a Cox proportional hazards model, and the miR-125b-2-3p level could act as an protective indication for the survival with the HR being 0.74 based on 586 cases of HCC. Furthermore, the effect of nitidine chloride (NC), a natural bioactive phytochemical alkaloid, on the regulation of miR-125b-2-3p and its potential targets was also investigated. The miR-125b-2-3p level was increased after NC treatment, while the expression of its potential target PRKCA was reduced. Above all, a low-expressed level of miR-125b-2-3p plays a tumor suppressive role in HCC.

Impact of Red Yeast Rice on Metabolic Diseases: A Review of Possible Mechanisms of Action

Metabolic diseases constitute a major public health burden and are linked with high morbidity and mortality. They comprise atherosclerosis dyslipidemia, diabetes, hypertension, and obesity. However, there is no single drug that can simultaneously treat multiple diseases with complex underlying mechanisms. Therefore, it is necessary to identify a class of adjuvant drugs that block the development of metabolic diseases from a preventive perspective. Red yeast rice is a food fermentation product widely used to promote blood circulation and remove blood stasis. Modern pharmacology has shown that red yeast rice exerts potential protective effects on the liver, pancreas, blood vessels, and intestines. Therefore, this study was carried out to analyze and summarize the effect of red yeast rice on several metabolic diseases and the mechanisms of action involved. It was found that red yeast rice may be beneficial in the prevention and treatment of metabolic diseases.

Biomonitoring of Aflatoxin B1 and Deoxynivalenol in a Rural Pakistan Population Using Ultra-Sensitive LC-MS/MS Method

There are limited data on exposure to mycotoxins in Pakistan. Here, we measured exposure to deoxynivalenol (DON), a common contaminant of wheat, and aflatoxin B1 (AFB1), a known contaminant of rice, using biomarkers of exposure. Wheat (n = 195) and rice (n = 62) samples were analyzed for AFB1 and DON levels, and the corresponding urinary biomarkers were analyzed in urine samples from a rural population (n = 264, aged 4-80 years, male 58%) using ultra-sensitive liquid chromatography-tandem mass spectrometry. AFB1 was detected in 66% of rice (5.04 ± 11.94 µg/kg) and 3% of wheat samples. AFM1 (hydroxylated form of AFB1)was detected in 69% of urine samples, mean 0.023 ± 0.048 ng/mL and DON was detected in 20% of urine samples, mean 0.170 ± 0.129 ng/mL. The maximum probable daily intake for DON derived from the urinary biomarker was 59.8 ng/kg b.w./day, which is below the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives' tolerable daily intake (1000 ng/kg b.w./day). However, for aflatoxin, the derived margin of exposure (MoE) of (13.2) was well below the safe MoE (10,000) suggested by the European Food Safety Authority. The calculated aflatoxin-associated cancer risk of 0.514/105 individuals/year suggests that measures should be taken to reduce the AFB1 contamination in food, particularly rice, in Pakistan.

Preparation of magnetic mesoporous silica from rice husk for aflatoxin B1 removal: Optimum process and adsorption mechanism

The liquid foodstuffs such as edible oil products remain a problem of excessive aflatoxin B1 (AFB1) content. This paper focused on the preparation of magnetic mesoporous silica (MMS) from rice husk ash for the removal of AFB1 in oil system. The MMS preparation process, adsorption conditions, structural characteristics, and adsorption mechanism were investigated. The optimum conditions for MMS preparation were pH 11.0 and 80°C for 24 h. The characterization results showed that magnetic particles were successfully embedded in the MMS and had high responsiveness to a magnetic field, which was advantageous for recyclability. The MMS had ordered uniform channels with a specific surface area of 730.98 m2/g and pore diameter of 2.43 nm. The optimum adsorption conditions were 2 h at 20°C. For AFB1 with an initial concentration of 0.2 μg/mL, the MMS adsorption capacity was 171.98 μg/g and the adsorption rate was 94.59%. The MMS adsorption isotherm fitted the Langmuir model well under the assumption of monolayer AFB1 adsorption with uniformly distributed adsorption sites on the MMS surface. The maximum amount of AFB1 adsorbed according to the Langmuir isotherm was 1118.69 μg/g. A quasi-second-order kinetic model gave a better fit to the process of AFB1 adsorption on MMS. The values of ΔH (-19.17 kJ/mol) and ΔG (-34.09, -34.61, and -35.15 kJ/mol at 283, 293, and 303 K, respectively) were negative, indicating that AFB1 adsorption on MMS was a spontaneous exothermic process. The results indicated that MMS was a promising material for AFB1 removal in oil system, and this study will serve as a guide for practical MMS applications.

Occurrence and Exposure Assessment of Aflatoxin B1 in Omena (Rastrineobola argentea) from Kenya

Omena (Rastrineobola argentea) is the most consumed fish species in Kenya. In this study, we assessed the occurrence of aflatoxin B1 (AFB1) in Omena and the potential health risk of AFB1 to Kenyan consumers of this fish. A total of 74 samples comprising Omena intended for human consumption and fish feed production were analyzed in this study. Aflatoxin levels in Omena were determined using the enzyme-linked immunosorbent assay (ELISA). Omena intended for fish feed production was most contaminated with a mean concentration of 46.93 μg·kg−1 (2.24–115.23 μg·kg−1) compared with Omena intended for human consumption (mean = 19.42 μg·kg−1, range = 2.01–49.30 μg·kg−1). Thirty-five positive samples (83.3%) exceeded the maximum level permitted (5 μg·kg−1) by the East Africa Community standard for food used for human consumption. The exposure dose of AFB1 from consuming Omena was estimated to be 1.34 ng·kg−1 BW day−1, and margin of exposure (MoE) value for AFB1 was found to be 126.3, which indicates health risk to Omena consumers. The results suggest that the current situation of aflatoxin contamination in Omena has an adverse effect on the health of the consumers as well as the animals. Therefore, more surveys are needed to understand the scope and extent of aflatoxin contamination in Omena.