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Background Aflatoxins are found in diverse foods widely consumed worldwide. This study investigated the association between aflatoxin exposure and (a) consumption of specific foods, (b) dietary diversity (DD), and (c) seasonality. Methods Women enrolled in the AflaCohort Study in Banke, Nepal (n = 1648) were asked how often they ate certain food items in the past 7 days and 24 h. Serum aflatoxin B1-lysine (AFB1-lys) adduct levels, measured during pregnancy, were determined using high-performance liquid chromatography. Multivariable ordinary least squares and quantile regression models were used to examine incremental increases in AFB1-lys adduct levels per frequency of food consumption and the relationship between DD, seasonality, and increases in AFB1-lys adduct. Results Roughly 94% of women were exposed to aflatoxin (geometric mean 1.37 pg/mg). Women in the 30th, 50th, and 70th quantiles of aflatoxin exposure who reported one more occasion of maize consumption in the past week showed increases in AFB1-lys adduct levels: 0.094, 0.112, and 0.109 pg/mg (p 1-lys adduct levels: 0.058 (p p p p 1-lys adduct levels at all quantiles of aflatoxin exposure (range: 0.313–1.101 pg/mg, p Conclusions Our findings justify integrated approaches to aflatoxin reduction, including regulatory, agricultural, and food safety interventions across the value chain and at the household level.

Aflatoxins are mycotoxins considered to be highly toxic and produce adverse effects on human health. These compounds, mainly aflatoxin B1 (AFB1), have been classified as human carcinogens, due to its association with the development of hepatocellular carcinoma. In Mexico, the study of aflatoxins has been focused on the evaluation of products of the basic basket, particularly on maize, which is the basis of the Mexican diet. On the other hand, most of these studies have been conducted in urban areas. Indigenous populations may be exposed to a higher risk than urban ones due to the high consumption of tortillas, the harvest and the storage conditions of their food; hence, AFB1 is frequently found contaminating maize, which is the main food source for Mexicans. There is scarce evidence of exposure in vulnerable populations, such as children. Therefore, the main objective of this research was to conduct a pilot study for the evaluation of exposure to AFB1 through the AFB1-lys adduct in 31 serum samples of children from indigenous communities in Mexico. AFB1-lys was measured by High Pressure Liquid Chromatography with fluorescence detector (HPLC-FLD), with limits of detection and quantification of 3.5 and 4.7 pg/ml, respectively. Results from this pilot study revealed that 13% of children were of short stature, 9.7% presented overweight and 6.5% obesity. 45% of the children presented detectable concentrations of AFB1-lys adduct, with a median (minimum-maximum) of 5.6 (4.8-6.5) pg of AFB1-lys adduct/mg of albumin. The AFB1-lysine exposure biomarker is an important tool for the surveillance of aflatoxins and their effects on health, so, following this intervention, it would be necessary to monitor the exposure of vulnerable populations to aflatoxins, especially in rural areas where foods are more contaminated.

Objective:Chronic aflatoxin exposure has been associated with childhood stunting (length-for-age/height-for-age < –2 sd), while data lacks for Bangladesh, a country with substantial burden of childhood stunting. This paper examined the association between aflatoxin exposure and childhood stunting in a slum setting of Dhaka city.Design:In this MAL-ED aflatoxin birth cohort study, plasma samples were assayed for aflatoxin B1-lysine adduct (AFB1-lys) by MS at 7, 15, 24 and 36 months of age for 208, 196, 173 and 167 children to assess chronic aflatoxin exposure. Relationship between aflatoxin exposure and anthropometric measures was examined by mixed-effects logistic regression models.Setting and participants:The study was conducted in Mirpur, Dhaka, where children were followed from birth to 36 months.Results:Prevalence of stunting increased from 21 % at 7 months to 49 % at 36 months of age. Mean AFB1-lys concentrations at 7, 15, 24 and 36 months were 1·30 (range 0·09–5·79), 1·52 (range 0·06–6·35), 3·43 (range 0·15–65·60) and 3·70 (range 0·09–126·54) pg/mg albumin, respectively, and the percentage of children with detectable AFB1-lys was 10, 21, 18 and 62 %, respectively. No association was observed between aflatoxin exposure and stunting in multivariable analyses. Factors associated with childhood stunting were age, low birth weight, maternal height, stool myeloperoxidase and number of people sleeping in one room.Conclusions:A relatively lower exposure to aflatoxin may not influence the linear growth of children. This finding indicates a threshold level of exposure for linear growth deficit and further investigation in other areas where higher concentrations of aflatoxin exposure exist.

The toxicity of aflatoxins results in cancer and liver disease. Several natural substances such as plants exhibited their ability to inhibit the initiation of aflatoxin carcinogenesis. The aim of this study was to evaluate the effect of Alchornea cordifolia on biomarkers in an aflatoxin B1 (AFB1) exposed rats. The contents of polyphenols, flavonoids and the antioxidant activity of A. cordifolia ethanolic leaf extract (EELac) were assessed. Groups of rats were treated orally with a daily dose of a mixture of AFB1 at a dose of 150 μg/kg body weight and EELac (50, 100 and 300 mg/kg body weight) for 21 days. Biomarkers of AFB1, such as the AFB1-lysine adduct and aflatoxin M1 were assayed in blood and urine, respectively, using an HPLC system with a fluorescence detector. The contents of polyphenols and flavonoids were 6783.23 ± 272.76 μg EAG/g and 10.54 ± 3.15% of dry matter, respectively. EELac showed a good antioxidant activity (IC50 = 12.65 ± 0.13 μg/mL). The administration of the mixture (AFB1 + EELac) at different doses significantly reduced the level of AFB1-lysine adduct from 14.04 ± 2.1 to 4.13 ± 0.9 ng/mg albumin and that of Aflatoxin M1 (AFM1) from 456 ± 16 to 220 ± 24 ng/mL (p 0.05). The rate of reduction was 70.58% for AFB1-lysine adduct and 51.75% for AFM1. A. cordifolia could be used in the prevention of toxicity induced by AFB1 on account of its high content in phenolic compounds.

Dried blood spots (DBS) were proposed as potentially viable method for exposure assessment of environmental toxicants in infant and young children. For this study, we validated an experimental protocol to quantify AFB1-lysine adduct in DBS samples of AFB1-treated F344 rats, as well as samples from human field study. Significant dose-response relationships in AFB1-lysine adduct formation were found in DBS samples of rats treated with single- and repeated-dose AFB1. AFB1-lysine levels in DBS samples were highly correlated with corresponding serum sample levels. The Person coefficients were 0.997 for the single-dose exposure, and 0.996 for the repeated-dose exposure. Levels of AFB1-lysine adduct had also good agreement between DBS and serum samples as shown by Bland-Altman plot analysis. For human field study samples (n = 36), a Pearson correlation coefficient of 0.784 was found between AFB1-lysine adduct levels of DBS and corresponding serum samples. Bland-Altman plots showed the distribution of the log differences between DBS and serum AFB1-lysine levels are within 95% confidence intervals. These results showed AFB1-lysine adduct levels in DBS cards and serum samples from animals and human samples are comparable, and the DBS technique and analytical protocol is a good means to assess AFB1 exposure in infant and children populations.

Aflatoxins are toxic metabolites of Aspergillus moulds and are widespread in the food supply, particularly in low‐ and middle‐income countries. Both in utero and infant exposure to aflatoxin B1 (AFB1) have been linked to poor child growth and development. The objective of this prospective cohort study was to investigate the association between maternal aflatoxin exposure during pregnancy and adverse birth outcomes, primarily lower birth weight, in a sample of 220 mother–infant pairs in Mukono district, Uganda. Maternal aflatoxin exposure was assessed by measuring the serum concentration of AFB1‐lysine (AFB‐Lys) adduct at 17.8 ± 3.5 (mean ± SD)‐week gestation using high‐performance liquid chromatography. Anthropometry and birth outcome characteristics were obtained within 48 hr of delivery. Associations between maternal aflatoxin exposure and birth outcomes were assessed using multivariable linear regression models adjusted for confounding factors. Median maternal AFB‐Lys level was 5.83 pg/mg albumin (range: 0.71–95.60 pg/mg albumin, interquartile range: 3.53–9.62 pg/mg albumin). In adjusted linear regression models, elevations in maternal AFB‐Lys levels were significantly associated with lower weight (adj‐β: 0.07; 95% CI: −0.13, −0.003; p = 0.040), lower weight‐for‐age z‐score (adj‐β: −0.16; 95% CI: −0.30, −0.01; p = 0.037), smaller head circumference (adj‐β: −0.26; 95% CI: −0.49, −0.02; p = 0.035), and lower head circumference‐for‐age z‐score (adj‐β: −0.23; 95% CI: −0.43, −0.03; p = 0.023) in infants at birth. Overall, our data suggest an association between maternal aflatoxin exposure during pregnancy and adverse birth outcomes, particularly lower birth weight and smaller head circumference, but further research is warranted.

This work reports the chemical synthesis of aflatoxin B1 (AFB1)-lysine based on procedures available in the literature, but using lysine without a protection group in the α-amine group. AFB1-exo-8,9-epoxide was obtained by epoxidation of AFB1 with chloroperoxybenzoic acid in dichloromethane and phosphate buffer. Purification and identification of the AFB1-lysine were conducted by liquid chromatography (LC), and its structure was confirmed by LC with mass spectrometer and diode-array detection. The preparation of AFB1-lysine using lysine without a protection group in the α-amine group was completed in 24 h, being a practical modification of available methods that can be reproduced in analytical laboratories.

Aflatoxins are one of the major risk factors in the multi-factorial etiology of human hepatocellular carcinoma. Therefore, the information on aflatoxins exposure is very important in the intervention planning in order to reduce the dietary intake of aflatoxins, especially among the children. This study investigated the relationship between aflatoxin B 1 (AFB 1 ) lysine adduct levers in serum and socio-demographic factors and dietary intake of aflatoxins from nuts and nut products in Penang, Malaysia. A cross-sectional field study was conducted in five districts of Penang. A survey on socio-demographic characteristics was administered to 364 healthy adults from the three main ethnic groups (Malay, Chinese and Indian). A total of 170 blood samples were successfully collected and tested for the level of AFB 1 –lysine adduct. 97% of the samples contained AFB 1 –lysine adduct above the detection limit of 0.4 pg/mg albumin and ranged from 0.20 to 23.16 pg/mg albumin (mean ± standard deviation = 7.67 ± 4.54 pg/mg albumin; median = 7.12 pg/mg albumin). There was no significant association between AFB 1 –lysine adduct levels with gender, district, education level, household number and occupation when these socio-demographic characteristics were examined according to high or low levels of AFB 1 –lysine. However, participants in the age group of 31–50 years were 3.08 times more likely to have high AFB 1 levels compared to those aged between 18 and 30 years ( P = 0.026). Significant difference ( P = 0.000) was found among different ethnic groups. Chinese and Indian participants were 3.05 and 2.35 times more likely to have high AFB 1 levels than Malay. The result of AFB 1 –lysine adduct suggested that Penang adult population is likely to be exposed to AFB 1 but at a level of less than that needed to cause direct acute illness or death.