Seasonal variation of aflatoxin M1 contamination in industrial and traditional Iranian dairy products

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.

Mach-Zehnder Interferometric Immunosensor for Detection of Aflatoxin M1 in Milk, Chocolate Milk, and Yogurt

Aflatoxin M1 (AFM1) is detected in the milk of animals after ingestion of aflatoxin B1-contaminated food; since 2002, it has been categorized as a group I carcinogen. In this work, a silicon-based optoelectronic immunosensor for the detection of AFM1 in milk, chocolate milk, and yogurt has been developed. The immunosensor consists of ten Mach-Zehnder silicon nitride waveguide interferometers (MZIs) integrated on the same chip with the respective light sources, and an external spectrophotometer for transmission spectra collection. The sensing arm windows of MZIs are bio-functionalized after chip activation with aminosilane by spotting an AFM1 conjugate with bovine serum albumin. For AFM1 detection, a three-step competitive immunoassay is employed, including the primary reaction with a rabbit polyclonal anti-AFM1 antibody, followed by biotinylated donkey polyclonal anti-rabbit IgG antibody and streptavidin. The assay duration was 15 min with limits of detection of 0.005 ng/mL in both full-fat and chocolate milk, and 0.01 ng/mL in yogurt, which are lower than the maximum allowable concentration of 0.05 ng/mL set by the European Union. The assay is accurate (% recovery values 86.7-115) and repeatable (inter- and intra-assay variation coefficients <8%). The excellent analytical performance of the proposed immunosensor paves the way for accurate on-site AFM1 determination in milk.

Research update on aflatoxins toxicity, metabolism, distribution, and detection: A concise overview

Serious health risks associated with the consumption of food products contaminated with aflatoxins (AFs) are worldwide recognized and depend predominantly on consumed AF concentration by diet. A low concentration of aflatoxins in cereals and related food commodities is unavoidable, especially in subtropic and tropic regions. Accordingly, risk assessment guidelines established by regulatory bodies in different countries help in the prevention of aflatoxin intoxication and the protection of public health. By assessing the maximal levels of aflatoxins in food products which are a potential risk to human health, it's possible to establish appropriate risk management strategies. Regarding, a few factors are crucial for making a rational risk management decision, such as toxicological profile, adequate information concerning the exposure duration, availability of routine and some novel analytical techniques, socioeconomic factors, food intake patterns, and maximal allowed levels of each aflatoxin in different food products which may be varied between countries.

Occurrence and exposure assessment of Aflatoxin M1 in milk and milk products in India

Milk containing Aflatoxin M₁ (AFM₁) poses a serious health risk to consumers. Present study was undertaken to determine levels of AFM₁ in 146 milk and value added dairy products sold in retail markets of Chhattisgarh, India using HPLC coupled with fluorescence detector. A total of 52 samples (35.6%) were found to contain AFM₁ with overall concentrations ranging from nd - 2.608 µg/L. The contamination levels were higher in non-fermented milk products than fermented milk products samples, although this difference was statistically non-significant (p > 0.05). AFM₁ concentrations above maximum permissible limits established by the European Commission were found in 94.2% of positive samples. Health risk assessments ascertained that the estimated daily intakes for AFM₁ is higher than the established tolerable daily intakes for both adults and children (Hazard Index > 1), there by implying a potentially high risk to consumer's health. Current investigation provides valuable information regarding contamination of raw as well as value added milk products sold in Indian markets. Therefore, to protect consumer's health and promote dairy trade; there is an urgent need to increase farmer's knowledge on good storage practices of feed and fodder. Further, stringent enforcement of food safety regulations is imperative to safeguard and promote human health.

Aspergillus flavus and Total Aflatoxins Occurrence in Dairy Feed and Aflatoxin M1 in Bovine Milk in Aguascalientes, Mexico

Contamination of food chains by toxigenic fungi and aflatoxins is a global problem that causes damage to human health, as well as to crop and livestock production. The objective is to evaluate Aspergillus flavus and total aflatoxins (AFs) occurrence in totally mixed rations (TMRs) for dairy cows and aflatoxin M1 (AFM1) in milk for human consumption. Ninety-nine dairy production units located in Aguascalientes, Mexico, were randomly selected, and samples were collected from TMRs, raw milk, and milk marketed in the city in two consecutive agricultural cycles. AFs were quantified in TMRs and milk by indirect enzyme immunoassay and HPLC; aflatoxigenic and molecular (PCR) capacity of monosporic A. flavus isolates in the feed was characterized. All feed, raw, and pasteurized milk samples showed aflatoxin contamination (26.0 ± 0.4 µg/kg, 32.0 ± 1.0, and 31.3 ± 0.7 ng/L, respectively), and a significant proportion (90.4, 11.3, and 10.3%) exceeded the locally applied maximum permissible limits for feed and milk (20.0 µg/kg and 50 ng/L). Aflatoxin contamination in both TMRs and milk indicated a seasonal influence, with a higher concentration in the autumn-winter cycle when conditions of higher humidity prevail. The results obtained suggest the existence of contamination by aflatoxigenic A. flavus and aflatoxins in the diet formulated for feeding dairy cows and, consequently, in the dairy food chain of this region of the Mexican Highland Plateau.

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.

Comparison of the microbial, physicochemical, and sensorial properties of raw and pasteurized Lighvan cheeses during ripening time

Traditional cheeses which are normally produced from raw milk are very popular due to their intense and unique taste and aroma. However, high microbial contamination of raw milk due to manual milking and secondary contamination may lead to many diseases in humans in Iran. Lighvan is a traditional starter-free locally made Iranian cheese that is made from raw ewe's milk. Since the use of raw milk in the preparation of cheese produces serious health problems, due to the limited ripening period of this type of cheese, this study aimed to evaluate the feasibility of preparing Lighvan cheese from pasteurized milk. For this purpose, different characteristics of cheese prepared with pasteurized milk were compared with raw milk cheese. The results showed a reduction in the microbial population over the ripening time in both types of cheeses. However, coliforms and Escherichia coli were seen in raw milk cheeses until the last day of ripening. Regarding chemical analyses, the water-soluble nitrogen fraction and lipolysis products increased during ripening. Moreover, the raw milk cheeses indicated a higher lipolysis index than the pasteurized ones. According to the obtained results from the sensory evaluation, the raw milk cheese indicated higher acceptability compared with the pasteurized milk cheese. However, since the presence of E. coli makes the cheese inedible, it seems that the pasteurization of milk is mandatory for the production of this type of cheese.

Aflatoxin M1 in Brazilian goat milk and health risk assessment

Contamination of goat milk with aflatoxin M₁ (AFM₁) is a public health concern. This study investigated filamentous fungi in goat feed and quantified AFM₁ in milk samples (n = 108) from goat fed forage and concentrate. Based on the detected AFM₁ concentration, risk assessment analyses were performed concerning the Estimated Daily Intake (EDI) for one-year-old children and adults. Filamentous fungi were found in goat feed samples in a range of 3.1 ± 1.9 to 4.2 ± 0.2 log CFU/g. Five genera were identified, to cite Aspergillus, Penicillium, Fusarium, Rhizopus and Acremonium. Aspergillus species comprised A. flavus, A. niger, and A. ochraceus. All goat milk samples were contaminated with AFM₁ (5.60-48.20 ng/L; mean 21.90 ± 10.28 ng/L) in amounts below the limits imposed by regulatory agencies. However, EDI values for AFM₁ through goat milk estimated for one-year-old children were above the Tolerable Daily Intake. The calculated Hazard Index for one-year-old children indicated potential risk of liver cancer due to goat milk consumption. The Margin of Exposure values to AFM₁ in one-year-old children and adults consuming goat milk as the unique milk source indicated increased health risk. Therefore, contamination of goat milk with AFM₁ should be considered a high priority for Brazil's risk management actions.

Grazing Mares on Pasture with Sycamore Maples: A Potential Threat to Suckling Foals and Food Safety through Milk Contamination

Simple Summary

Equine atypical myopathy is seasonal poisoning resulting from the ingestion of seeds and seedlings of the sycamore maple that contains toxins. Literature mentions several cases of intoxication among gravid mares and in unweaned foals. The objective of this study was to determine whether the toxins responsible for atypical myopathy could pass to the foal via suckling. Four mares that were pasturing with sycamore in the vicinity were milked. Analysis revealed the presence of toxins in milk. This unprecedented observation could partially explain cases of unweaned foals suffering from atypical myopathy. However, a transplacental transfer of the toxin cannot be excluded for newborn cases. Besides being a source of contamination for offspring, milk contamination by toxins from fruits of trees of the Sapindaceae family might constitute a potential risk for food safety regarding other species’ raw milk or dairy products.

Abstract

Equine atypical myopathy (AM) is seasonal intoxication resulting from the ingestion of seeds and seedlings of the sycamore maple (Acer pseudoplatanus) that contain toxins, among them, hypoglycin A (HGA). Literature mentions several cases of AM among gravid mares and in unweaned foals. The objective of this study was to determine whether HGA and/or its metabolite are present in milk from grazing mares exposed to sycamore maple trees as confirmed by detection of HGA and its metabolite in their blood. Four mare/foal couples were included in the study. Both HGA and its metabolite were detectable in all but one of the milk samples. To our knowledge, this is the first study describing transfer of HGA to the milk. This unprecedented observation could partially explain cases of unweaned foals suffering from AM. However, a transplacental transfer of the toxin cannot be excluded for newborn foals. Besides being a source of contamination for offspring, milk contamination by toxins from fruits of trees of the Sapindaceae family might constitute a potential risk for food safety regarding other species’ raw milk or dairy products.

Aflatoxin M1 detection by ELISA in raw and processed milk in Bangladesh

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Immunologically aflatoxin M1 was detected in raw and processed milk in Bangladesh.

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Aflatoxin M1 mean level was found to be highest in raw milk (699.07 ng/kg).

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EC and US regulations exceeded in 75 % and 43 % of contaminated samples, respectively.

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Aflatoxin M1 existence level in milk can be detrimental to human health.

An analysis was accomplished to get information regarding presence of highly toxic and carcinogenic aflatoxin M1 (AFM1) in raw and processed samples of milk applying ELISA (enzyme linked immunosorbent assay). Investigation of a set of 100 samples (n=100) taken from different regional small-scale farms as well as grocery stores of Bangladesh containing three groups of milk including raw (n=50), pasteurized (n=25) and UHT (n=25), exhibited in total 53% AFM1 contamination where 70% contamination was found in raw milk ranging from 22.79−1489.28 ng/kg (mean value 699.07 ng/kg), 52% in pasteurized milk ranging from 18.11−672.18 ng/kg (mean value 99.77 ng/kg) and 20% in UHT milk ranging from 25.07−48.95 ng/kg (mean value 35.46 ng/kg). Among all the positive samples, 75% contaminated samples were above the European Communities prescribed limits (50 ng/kg) while having 25% samples still below this limit whereas 43% samples crossed the accepted limit of US regulations/Codex Alimentarius Commission regulations (500 ng/kg). Thus the findings of this study may lead to increase awareness regarding health impact of aflatoxin M1 and implementation of strict regulations by law enforcement bureaus of Bangladesh.

Aflatoxin M1 in Nicaraguan and locally made hard white cheeses marketed in El Salvador

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Cheeses marketed in El Salvador have high prevalence of Aflatoxin M₁ contamination.

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Cheese contamination by Aflatoxin M₁ is endemic in both El Salvador and Nicaragua.

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Aflatoxin M₁ contamination in cheeses is higher during dry season.

Aflatoxin M₁ is a carcinogenic and genotoxic metabolite of Aflatoxins present in food contaminated by fungi for lactating cattle, it is excreted through milk and when used to make cheese, the toxin will also be transferred to the dairy. The contamination of unripened hard white cheese with AFM₁ seems to vary according to the season of the year, possibly due to the change of foodstuff, from fresh pasture in the rainy season to dried foods in the dry season and vice versa. This research determined both the prevalence and contents of AFM₁ in cheeses of local and Nicaraguan origin marketed in El Salvador, as well as the changes occurred according to the season and the association between levels of AFM₁ with meteorological parameters. The significantly higher prevalence of AFM₁ contamination in both local cheeses and Nicaraguans, was found in the dry season and the lowest in the rainy season (41 % vs. 20 %; 31 % vs. 0%, respectively), the same trend was observed in AFM₁ contents (0.076 vs. 0.036 μg/kg; 0.050 vs. 0.021 μg/kg, respectively). A significant association was demonstrated between levels of AFM₁ with the averages of accumulated rainfall and relative humidity according to the sampled season. The prevalence of AFM₁ in cheeses indicate that El Salvador and Nicaragua are endemic to dairy contamination by that mycotoxin. Seasonal variation may be due to a lack of rainfall, that promotes the growth of aflatoxigenic fungi in the crops of raw materials, which will be used for feedstuff intended for dairy cattle, thus, the consumption of contaminated food will cause the temporary increase of AFM₁ in milk and their derivatives.

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.

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.

Current research and prevention of aflatoxins in China

Since their discovery in the 1960s, aflatoxins were found to have a considerable impact on the health of humans and animals as well as the country’s economy and international trade. Aflatoxins are often found in nuts, cereals and animal feeds, which has a significant danger to the food industry. Over the years, several steps have been undertaken worldwide to minimise their contamination in crops and their exposure to humans and animals. China is one of the largest exporters and importers of food and animal feed. As a result, many studies have been carried out in China related to aflatoxins, including their distribution, pollution, detection methods, monitoring, testing and managing. Chinese scientists studied aflatoxins in microbiological, toxicological, ecological effects as well as policies relating to their controlling. China has thus put into practice a number of strategies aiming at the prevention and control of aflatoxins in order to protect consumers and ensure a safe trade of food and feed, and the status and enlargement of these strategies are very important and useful for many consumers and stakeholders in China. Therefore, this article aims at the detriment assessments, regulations, distribution, detection methods, prevention and control of aflatoxins in China. It equally provides useful information about the recent safety management systems in place to fight the contamination of aflatoxins in food and feed in China.

Mycotoxins in maize harvested in Republic of Serbia in the period 2012-2015. Part 1: Regulated mycotoxins and its derivatives

The main objective of this study was to apply a liquid chromatography-tandem mass spectrometric method to investigate the presence of 20 mycotoxins in 204 maize samples harvested in Northern Serbia in the period 2012-2015, including seasons with extreme drought (2012), hot and dry conditions (2013 and 2015) and extreme precipitation (2014). Between 2 and 20 mycotoxins contaminated examined samples. In samples collected from each year, all of six examined fumonisins were detected with very high prevalence (from 76% to 100%). Aflatoxin B₁ was detected in 94% and 90% maize samples from 2012 and 2015, respectively. In samples from year 2014, deoxynivalenol, zearalenone and its derivatives were detected in 100% of samples. Furthermore, ochratoxin A (25%) was the most predominant in samples from 2012. The obtained results indicate that changes in weather conditions, recorded in the period of four years, had significant influence on the occurrence of examined mycotoxins in maize.

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.

Aflatoxins in Food and Feed: An Overview on Prevalence, Detection and Control Strategies

Aflatoxins produced by the Aspergillus species are highly toxic, carcinogenic, and cause severe contamination to food sources, leading to serious health consequences. Contaminations by aflatoxins have been reported in food and feed, such as groundnuts, millet, sesame seeds, maize, wheat, rice, fig, spices and cocoa due to fungal infection during pre- and post-harvest conditions. Besides these food products, commercial products like peanut butter, cooking oil and cosmetics have also been reported to be contaminated by aflatoxins. Even a low concentration of aflatoxins is hazardous for human and livestock. The identification and quantification of aflatoxins in food and feed is a major challenge to guarantee food safety. Therefore, developing feasible, sensitive and robust analytical methods is paramount for the identification and quantification of aflatoxins present in low concentrations in food and feed. There are various chromatographic and sensor-based methods used for the detection of aflatoxins. The current review provides insight into the sources of contamination, occurrence, detection techniques, and masked mycotoxin, in addition to management strategies of aflatoxins to ensure food safety and security.

Occurrence and Seasonal Variations of Aflatoxin M1 in Milk from Punjab, Pakistan

The manifestation of aflatoxins in feed and food is a major issue in the world as its presence leads to some health problems. This study investigates the incidence of aflatoxin M₁ (AFM₁) contamination in raw milk samples which were collected from Punjab, Pakistan. The Cluster Random Sampling technique was used to collect 960 milk samples from five different regions, and samples were collected every month. The AFM₁ level in raw milk was analyzed by the ELISA technique. The findings demonstrate that 70% of samples exceeded the United States permissible maximum residue limits (MRL 0.50 µg/L), with an overall AFM₁ level that ranged from 0.3 to 1.0 µg/L. AFM₁ contamination varied with the season: The highest average contamination was detected in winter (0.875 µg/L), followed by autumn (0.751 µg/L), spring (0.654 µg/L), and summer (0.455 µg/L). The Eastern region exhibited the highest average AFM₁ contamination (0.705 µg/L). Milk samples from the Northern region were found to be widely contaminated, as 86.9% samples exceeded the US MRL, followed by the Eastern region, with 72.3% samples being contaminated with >0.5 µg/L AFM₁. The study indicated that the raw milk supply chain was heavily contaminated. Recommendations and remedial measures need to be developed by regulatory authorities to improve the raw milk quality.

Risk associated with the intake of aflatoxin M1 from milk in Iran

Aflatoxin M1 is an oxidative metabolite of aflatoxin B1 formed in liver and excreted into milk, urine and faeces of dairy cattle and other mammalian species. The International Agency for Research on Cancer classified aflatoxin M1 in Group 2B because of its potential to get bioactivated to a mutagen analogous to aflatoxin B1. Risk assessments are undertaken to guide food regulators and scientists in risk management processes, such as the legislative levels or guideline targets for mycotoxins in food supplies. Using existing international resources for hazard data and local exposure data, and based on cancer potency as the endpoint, the risk of exposure to aflatoxin M1 in milk for the Iranian population was calculated considering various scenarios. During 2014-2015, 518 samples were collected from the market and tested for aflatoxin M1 contamination by HPLC-FLD. The most probable scenarios calculated as mean occurrence multiplied by the mean consumption in consumers of milk, and for maximum level allowed for aflatoxin M1 in milk with 99 percentiles of milk consumption showed the risk of 0.08 and 0.72 additional liver cancer cases per year for the Iranian population, respectively. Thus, our study reveals a low risk and that the current maximum limit of 100 ng/l for aflatoxin M1 in milk, heat treated milk and flavoured milk is sustainable.

A study on the aflatoxin M1 rate and seasonal variation in pasteurized cow milk from northwestern Iran

Present study aims to assess aflatoxin M1 (AFM1) contamination in 100 samples of pasteurized milk which were conventionally gathered during spring, summer, autumn, and winter from supermarkets located in Maragheh city of northwestern Iran. Samples were evaluated for AFM1 with a high-performance liquid chromatography (HPLC) method and with fluorimetric detection. The results showed that approximately 44% (11.25) of samples in winter, 32% (8.25) of samples in spring, 24% (6.25) of samples in summer, and 20% (5.25) of samples in autumn had AFM1 concentrations that exceeded the limit (0.05 μg/l) set by the European, Codex Alimentarius Commission and Iran standards. According to the statistical analysis of the data, there was no significant variation between the mean content of AFM1 during different seasons (P = 0.076). The results of our study suggest a high level of contamination of AFM1 in pasteurized milk in all seasons which may be due to the fact that milk supply for dairy factories is provided from dairy farms that are low in livestock feed quality. In Iran, pasteurized milk is consumed more than other milk products by all age groups. The total daily aflatoxin intake from contaminated milk and possibly other food products will be a significant risk to public health.

Aflatoxin M1 in cow, sheep, and donkey milk produced in Sicily, Southern Italy

Samples (n = 485) of raw (n = 394) or heat-treated (n = 91) milk of three different species (cow, n = 170; sheep, n = 133; donkey, n = 84), collected 2013-2016 in Western Sicily (Southern Italy), were analyzed for aflatoxin M₁ (AFM₁) by enzyme-linked immunosorbent assay (ELISA). Positive ELISA results were further analyzed by HPLC with fluorescence detection. Both methods had a detection limit for AFM₁ in milk of 7 ng kg^-1. ELISA yielded 12.9 and 5% positives in cows and sheep milk, respectively, all samples of donkey milk were negative. Levels of AFM₁ were in most cases at 0.007-< 0.05 μg kg^-1, only two samples (sheep milk) slightly exceeded the European Union maximum level of 0.05 μg kg^-1. Only 6% of the samples were positive for AFM₁ in a concentration range of 0.008-0.15 μg kg^-1. Only milk samples collected directly from farms were positive. Overall, the levels were much lower than previously reported for Southern Italy cow and sheep milk samples purchased in retail stores. The results of this work indicate a continuous improvement of the feeding techniques on dairy farms of Southern Italy, which is essential to ensure consumers' protection.

Aflatoxins in maize harvested in the Republic of Serbia over the period 2012-2016

Aflatoxins (AFs) are one of the most frequent contaminants in maize. The Republic of Serbia represents a leader in terms of maize production and exports in Europe. In recent years, Serbia faced climate changes. Therefore, the main objective of this study was to examine AF occurrence in 3000 maize samples collected during 2012-2016. In maize samples from 2012, 2013, 2015, and 2016, AFs were detected in 72.3%, 24.7%, 36.7%, and 5.0% of the samples, in concentration ranges of 1.0-111.2, 1.2-65.2, 1.1-76.2, and 1.3-6.9 µg kg^-1, respectively. Contrary to this, in maize samples from 2014, no AFs were detected. Analysis of weather conditions indicates that 2012 was characterised by extreme drought conditions, 2013 and 2015 by lack of precipitation and high air temperatures, 2014 as the rainiest year in these years, while 2016 had moderate weather conditions.

Occurrence of Aflatoxin M1 in Raw Milk from Manufacturers of Infant Milk Powder in China

This survey was performed to investigate the occurrence of aflatoxin M1 (AFM1) contamination of raw milk from manufacturers of infant milk powder in China. A total of 1207 raw milk samples were collected overall from four seasons of 2016 in Northeast China, Northwest China, Northern China, and Central China (11 provinces and one municipality). Results showed that 56 of the 1207 raw milk samples (4.64%) were positive for AFM1, which were obtained from Heilongjiang (two samples), Gansu (one sample), Shaanxi (46 samples), Beijing (one sample), and Hunan (six samples) provinces. None of the raw milk samples from manufacturers of infant milk powder exceeded the Chinese limit (62.5 ng/L) in 2016. Only a few raw milk samples were not suitable for use in infant milk according to EU (European Union) or U.S. infant milk limits. Furthermore, based on this survey and previous studies, it is particularly important to avoid AFM1 contamination in raw milk during the winter.

Occurrence of aflatoxin M1 in milk samples from Italy analysed by online-SPE UHPLC-MS/MS

The occurrence of aflatoxin M1 in 69 milk samples collected in a south region of Italy in 2016 was evaluated. The samples were analysed using an automated method based on online SPE coupled with UHPLC tandem mass spectrometry. After a salt induced liquid-liquid extraction with acetonitrile to remove protein from milk, the extract was diluted with water and analysed using an automated online SPE MS/MS method. Among the analysed samples no one had AFM1 higher than the legally allowable limits whereas 71.4% of the other analysed samples were above the LOD of the method. The highest contamination level of AFM1 was found in pasteurised milk (44.39 ng kg^-1). The results show the worrying and widespread of AFM1 contamination, highlighting the necessity of monitoring studies in order to evaluate the reduction of the maximum legal limit.