Exposure of newborns to aflatoxin M1 and B1 from mothers' breast milk in Ankara, Turkey

The concentration of aflatoxin M1 in the mothers' milk in Khorrambid City, Fars, Iran

INTRODUCTION

Aflatoxins are secondary toxic metabolites produced by certain group of Aspergillus species in suitable conditions. These toxins are highly toxic, immunosuppressive, mutagenic, teratogenic and carcinogenic metabolites. The purpose of this study was to detection aflatoxin M1 concentration in mother's milk from rural area of Khorrambid town of Fars Province.

MATERIALS AND METHODS

In this study, 87 milk samples of mothers were collected by cluster sampling methods in the period between June and July 2011 and the amount of aflatoxin M1 was measured by a competitive ELISA method.

RESULTS

From 87 mother's milk, 24 (27.6%) samples were contaminated with aflatoxin M1 with mean concentration of 0.56 ± 1.23 pg/ml (range 0.13-4.91 pg/ml).

CONCLUSION

The amount of aflatoxin M1 in mothers' milk was lower than 50 ng/l (Europe Union and Iranian standard). Detection of Aflatoxin M1 in mothers' milk is due to consuming contaminated food. This contamination not only threatens the health of the mothers but also has irreversible effects on the growth and health of their babies.

Prevalence of ochratoxin a in human milk in the khorrambid town, fars province, South of iran

BACKGROUND

Ochratoxins belong to a group of mycotoxins produced as the secondary metabolites by filamentous fungi, such as Aspergillus and Penicillium. These toxins may be teratogenic, mutagenic, hepatotoxic, nephrotoxic, and may have immunosuppressive effects and pose a serious health problems to exposed humans and animals.

OBJECTIVES

The present study aimed to determine the level of ochratoxin A (OTA) in the samples of mothers' milk in the Khorrambid Town, Fars Province, south of Iran.

MATERIALS AND METHODS

Between June and July 2011, samples of human milk were obtained from 87 mothers. The samples were diluted by absolute methanol at 1:4 ratio and after centrifugation, the supernatant was directly used to determine the level of OTA using competitive enzyme-linked immunosorbent assay (ELISA).

RESULTS

Among 87 human milk samples, 84 (96.6%) samples had positive results for OTA at a mean level of 24.57 ± 13.6 ng/L. According to the European Union Standard, 14 (16%) positive samples revealed more than the maximum limit of 40 ng/L for ochratoxin (range, 1.6-60 ng/L).

CONCLUSIONS

Presence of OTA in the milk of mothers denotes a probable consumption of a contaminated foods. Therefore, regular monitoring of foods for presence of mycotoxins for lactating mothers seems necessary.

Association between aflatoxin M1 exposure through breast milk and growth impairment in infants from Northern Tanzania

Infants breastfeeding from mothers consuming aflatoxin contaminated foods may be exposed to aflatoxin M1 (AFM1), a metabolite of aflatoxin B1. This study estimated the association between AFM1 exposure levels and growth indicators, for infants under six months of age in the Rombo district in Northern Tanzania. A total of 143 infants and their mothers were involved. Breast-milk samples, infants' anthropometric data and 24 h dietary recall for mothers were taken at the 1st, 3rd and 5th months of children age. AFM1 contaminations in the samples were determined using HPLC. Aflatoxin M1 exposure by an infant was estimated by multiplying contamination in the breast milk consumed by him/her with the breast milk intake recorded by the United States Environmental Protection Agency for infants of his/her age divided by the infant's body weight. All the breast-milk samples were contaminated by AFM1 at levels ranging from 0.01 to 0.55 ng/ml. Above 90% of samples exceeded the EU limit of 0.025 ng/ml for infants' foods while over 76% exceeded the EU limit of 0.05 ng/ml for dairy milk and milk products. Only 1% of the samples exceeded the limit of 0.5 ng/ml set for dairy milk in the United States and several countries in Asia. AFM1 Exposures ranged from 1.13-66.79 ng/kg body weight per day. A small but significant (P<0.05) inverse association was observed between AFM1 exposure levels and weight for age Z-score or height for age Z-score. Appropriate strategies should be applied to minimise aflatoxin B1 exposure in lactating mothers in order to protect infants from AFM1 exposure.

The molecular epidemiology of chronic aflatoxin driven impaired child growth

Aflatoxins are toxic secondary fungal metabolites that contaminate dietary staples in tropical regions; chronic high levels of exposure are common for many of the poorest populations. Observations in animals indicate that growth and/or food utilization are adversely affected by aflatoxins. This review highlights the development of validated exposure biomarkers and their use here to assess the role of aflatoxins in early life growth retardation. Aflatoxin exposure occurs in utero and continues in early infancy as weaning foods are introduced. Using aflatoxin-albumin exposure biomarkers, five major studies clearly demonstrate strong dose response relationships between exposure in utero and/or early infancy and growth retardation, identified by reduced birth weight and/or low HAZ and WAZ scores. The epidemiological studies include cross-sectional and longitudinal surveys, though aflatoxin reduction intervention studies are now required to further support these data and guide sustainable options to reduce the burden of exposure. The use of aflatoxin exposure biomarkers was essential in understanding the observational data reviewed and will likely be a critical monitor of the effectiveness of interventions to restrict aflatoxin exposure. Given that an estimated 4.5 billion individuals live in regions at risk of dietary contamination the public health concern cannot be over stated.

Aflatoxin M1 contamination of human breast milk in Isfahan, Iran

BACKGROUND

During the last decades there has been great attention paid to aflatoxins. They are highly toxic, immunosuppressive, mutagenic, teratogenic, and carcinogenic compounds. Aflatoxin M1 (AFM1), a hydroxylated metabolite of aflatoxin B1 (AFB1), is formed in the liver and excreted into the breast milk. It is considered to cause certain hygienic risks for infant health. The aim of this study was to evaluate the presence of the AFM1 in the breast milk using AFM1 in milk as a biomarker for exposure to aflatoxin B1 and determine the level of AFM1 contamination in the lactating mothers in Isfahan, Iran.

MATERIALS AND METHODS

This study was carried out on 80 lactating women randomly selected from two urban health centers. Mother's milk samples and information on food intake were collected from the participants using structured food-frequency questionnaire. Breast milk samples were tested for AFM1 by a competitive ELISA technique.

RESULTS

Our findings showed that only one sample was contaminated with AFM1 with concentrations of 6.8 ng/L. However, the AFM1 level in this sample was lower than the maximum tolerable limit (25 ng/L) accepted by the European Communities and Codex Alimentarius.

CONCLUSION

Although the concentration of AFM1 in none of the samples was higher than the acceptable level, the presence of AFM1 in only one of them confirms the need for developing strategies to reduce exposure to aflatoxin in foods and to carry out biological monitoring of aflatoxins as a food quality control measure routinely.

Simultaneous analysis of aflatoxins B1, B2, G1, G2, M1 and ochratoxin A in breast milk by high-performance liquid chromatography/fluorescence after liquid-liquid extraction with low temperature purification (LLE-LTP)

The aims of this study were to optimize and validate a methodology for the simultaneous analysis of aflatoxins B1, B2, G1, G2, M1 (AFB1, AFB2, AFG1, AFG2, AFM1) and ochratoxin A (OTA) in breast milk, and to analyze these mycotoxins in samples obtained from human milk banks in the Federal District, Brazil. The optimized analytical method was based on liquid-liquid extraction with low temperature purification (3.25mL of acidified acetonitrile+0.75mL of ethyl acetate), followed by analysis by high-performance liquid chromatography with fluorescence detector (HPLC/FLD) and a photochemical post-column reactor. Limits of quantification (LOQ) ranged from 0.005 to 0.03ng/mL, recoveries from 73 to 99.5%, and relative standard deviations (RSD) from 1.8 to 17.3%. The LLE-LTP extraction method was shown to be simple and cost-effective, since no columns were needed for clean-up. Only 2 of the 224 breast milk samples analyzed were positive for the mycotoxins, both samples containing AFB2 at the LOQ level (0.005ng/mL). The identity of the mycotoxin detected was confirmed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). This result indicates that infants who are fed with breast milk from the milk banks are not at risk from aflatoxin and ochratoxin exposure.

Aflatoxin m1 in milk products in china and dietary risk assessment

This study was conducted to investigate the occurrence of aflatoxin M1 (AFM1) in milk products in China using the competitive enzyme-linked immunosorbent assay method and to estimate the dietary exposure to this toxin through a probabilistic approach. Based on the exposure assessment results, a quantitative cancer potency formula developed by the Joint Food and Agriculture Organization and World Health Organization Expert Committee on Food Additives was applied to assess the cancer risk. AFM1 was detected in 48.07% of the milk samples and 4.49% of the yoghurt samples. No samples contained AFM1 above the current regulatory limit in China. The simulated AFM1 intake (90% confidence interval) in various sex-age groups ranged from 0.023 (0.021 to 0.023) ng/kg of body weight per day for 30- to 45-year-old men to 0.382 (0.354 to 0.386) ng/kg of body weight per day for 2- to 4-year-old girls at the 99th percentile. The cancer risk of AFM1 to the general population of China was assessed to be 0.129 cancer cases per year per 10(8) persons at the 99th percentile. These results indicate that the health risk associated with AFM1 in milk in China is relatively low.

Aflatoxin species: their health effects and determination methods in different foodstuffs

Carcinogenic and mutagenic properties of aflatoxin species are known in literature. Their intake over a long time period might be health-dangerous for human even at trace levels. It is well known that different foodstuffs can be contaminated by aflatoxin species through growing and storage. Due to the serious health effects, sensitive determination of aflatoxin species in any matrices related with the human being is very crucial at trace levels. In literature, there are sensitive techniques to analyze the different samples for the contents of their aflatoxin species. Each technique has some advantages and disadvantages over the other techniques. This review aims to summarize the different health effects of aflatoxin species, development of analytical techniques and applications of developed techniques in a variety of matrices.

Modulation of macrophage activity by aflatoxins B1 and B2 and their metabolites aflatoxins M1 and M2

Aflatoxins are natural contaminants frequently found both in food and feed. Many of them exert immunomodulatory properties in mammals; therefore, the aim of the current study was to investigate immune-effects of AFB1, AFB2, AFM1 and AFM2, alone and differently combined, in J774A.1 murine macrophages. MTT assay showed that AFB1, alone and combined with AFB2, possess antiproliferative activity only at the highest concentration; such effect was not shown by their hydroxylated metabolites, AFM1 and AFM2, respectively. However, the immunotoxic effects of the aflatoxins evaluated in the current study may be due to the inhibition of production of active oxygen metabolites such as NO. Cytofluorimetric assay in macrophages exposed to aflatoxins (10-100 μM) revealed that their cytoxicity is not related to apoptotic pathways. Nevertheless, a significant increase of the S phase cell population accompanied by a decrease in G0/G1 phase cell population was observed after AFB1 treatment. In conclusion, the results of the current study suggest that aflatoxins could compromise the macrophages functions; in particular, co-exposure to AFB1, AFB2, AFM1 and AFM2 may exert interactions which can significantly affect immunoreactivity.

Developments in mycotoxin analysis: an update for 2010-2011

This review highlights developments in mycotoxin analysis and sampling over a period between mid-2010 and mid-2011. It covers the major mycotoxins: aflatoxins, Alternaria toxins, ergot alkaloids, fumonisins, ochratoxin, patulin, trichothecenes, and zearalenone. Analytical methods for mycotoxins continue to be developed and published. Despite much interest in immunochemical methods and in the rapid development of LC-MS methodology, more conventional methods, sometimes linked to novel clean-up protocols, have also been the subject of research publications over the above period. Occurrence of mycotoxins falls outside the main focus of this review; however, where relevant to analytical method development, this has been mentioned.

Exposure to toxic chemicals in the diet: is the Brazilian population at risk?

In Brazil, in the last 20 years, dietary risk assessments have been conducted on pesticides, mycotoxins, food additives, heavy metals (mainly mercury), environmental contaminants (mainly DDT) and acrylamide, a compound formed during food processing. The objectives of this paper were to review these studies, discuss their limitations and uncertainties and identify the most critical chemicals that may pose a health risk to Brazilian consumers. The studies have shown that the cumulative intake of organophosphorus and carbamate pesticides by high consumers of fruits and vegetables may represent a health concern (up to 169% of the ARfD), although the benefits of consuming large portions of those foods most probably overcome the risks. High consumers of maize products may also be at risk due to the presence of fumonisin (355% of the PMTDI), a mycotoxin present at high levels in Brazilian maize. The studies conducted in the Brazilian Amazon have shown that riparian fish consumers are exposed to unsafe levels of mercury. However, this is a more complex issue, as mercury levels in the region are naturally high and the health benefits of a fish-based diet are well known. Studies conducted both in Brazil and internationally on acrylamide have shown that the exposure to this genotoxic compound, mainly from the consumption of French fries and potato chips, is of health concern. Reducing the population dietary exposure to toxic chemicals is a challenge for government authorities and food producers in all countries. Management strategies aimed at decreasing exposure to the critical chemicals identified in this review involve limiting the use or eliminating highly toxic pesticides, implementing good agricultural practices to decrease maize contamination by fumonisins, educating local fish-eating communities toward a fish diet less contaminated by mercury, and changing dietary habits concerning the consumption of fried potatoes, the main processed food containing acrylamide.

Aflatoxins and growth impairment: a review

Aflatoxins, fungal toxins produced by Aspergillus flavus and Aspergillus parasiticus in a variety of food crops, are well known as potent human hepatocarcinogens. Relatively less highlighted in the literature is the association between aflatoxin and growth impairment in children. Foodborne aflatoxin exposure, especially through maize and groundnuts, is common in much of Africa and Asia--areas where childhood stunting and underweight are also common, due to a variety of possibly interacting factors such as enteric diseases, socioeconomic status, and suboptimal nutrition. The effects of aflatoxin on growth impairment in animals and human children are reviewed, including studies that assess aflatoxin exposure in utero and through breastfeeding. Childhood weaning diets in various regions of the world are briefly discussed. This review suggests that aflatoxin exposure and its association with growth impairment in children could contribute a significant public health burden in less developed countries.

Assessment of exposure of Egyptian infants to aflatoxin M1 through breast milk

BACKGROUND

Mothers are exposed to many toxins that can reach their infants through breast milk. One of these toxins is aflatoxins, produced by Aspergillus fungus. Aspergillus colonizes grains, especially in tropical regions where there is high temperature and humidity. Aflatoxins are highly toxic, mutagenic, teratogenic, and carcinogenic. One of these is aflatoxin B1 that is excreted in breast milk as aflatoxin M1 (AFM1).

MATERIALS AND METHODS

This is a cross-sectional study in which 150 mother-infant dyads were included. All the infants were exclusively breastfed. Infant weights' standard deviation scores were documented at birth and at 6 months. At 6 months, before starting weaning, AFM1 was measured in breast milk by enzyme-linked immunosorbent assay and by liver enzymes; alanine aminotransferase (ALT) and aspartate aminotransferase (AST) for all mothers and infants.

RESULTS

Ninety-eight mothers (65.3%) had AFM1-positive breast milk samples (AFM1>0.05 μg/l according to the European Community and Codex Alimentarius). AFM1 levels ranged between 0.2 and 19.0 μg/l (mean: 7.1±5.0 μg/l). In cases considered negative, AFM1 levels ranged between 0.01and 0.05 μg/l (mean: 0.04±0.01 μg/l). Infants of AFM1-positive mothers had lower weight standard deviation scores at birth and at 6 months (P=0.04 and 0.0001). ALT and aspartate aminotransferase of mothers and ALT of infants were significantly higher in dyads having AFM1-positive breast milk (P=0.0001, 0.0001, and 0.03, respectively).

CONCLUSION

Aflatoxins represent a real threat in Egypt. The higher liver enzymes in AFM1-positive cases might represent an alarm toward future development of hepatocellular carcinoma.

RECOMMENDATIONS

Cooperation of ministries is recommended to combat this problem. The public should be educated about proper food storage and about the hazards of aflatoxin ingestion.

Assessment of aflatoxin M1 contamination in pasteurized and UHT milk marketed in central part of Iran

This study was conducted as a screening survey to determine the occurrence of aflatoxin M1 (AFM1) in 225 commercial liquid milk samples composed of pasteurized milk (116 samples) and UHT milk (109 samples) obtained from popular markets in central part of Iran. The competitive enzyme-linked immunosorbent assay method was employed to determine level of the toxin in the samples. Aflatoxin M1 was detected in 151 (67.1%) samples, consisted of 83 (71.5%) pasteurized milk samples (mean: 52.8 ng/l; range: 5.8-528.5 ng/l) and 68 (62.3%) UHT milk samples (mean: 46.4 ng/l; range: 5.6-515.9 ng/l). Considering the US FDA and Iranian national standard limits for AFM1 in milk (500 ng/l), 2 samples (1.7%) of pasteurized and 3 samples (2.7%) of UHT milk had levels above the maximum tolerance limit. However, according to European Commission limit (50 ng/l), this figure increased to 31 (26.7%) and 19 (17.4%) samples for pasteurized and UHT milk, respectively. The results indicated that the contamination of the samples with AFM1 in such a level could be a serious public health problem at the moment. This paper represents the data of the first survey on the occurrence of AFM1 in commercial liquid milk marketed in central part of Iran.