Human Health Risk Associated with the Consumption of Aflatoxins in Popcorn.

INTRODUCTION: Aflatoxins are secondary metabolites produced mainly by the molds Aspergillus flavus, A. parasiticus and A. nomius, and they contaminate cereals, dry fruits, oilseeds and spices. Aflatoxins have harmful effects in animals and humans, inducing vomiting, diarrhea, hepatitis, cirrhosis, immunosuppression, miscarriages, mutagenic and teratogenic effects, resulting in different cancers. Popcorn (Zea mays everta) is a cereal susceptible to aflatoxin contamination, and there are no reports about the risk of its consumption. PURPOSE: A study on the incidence and consumption of aflatoxins in popcorn marketed in the city of Veracruz, Mexico was conducted and evaluated to carry out a risk assessment for human health. METHODS: To obtain popcorn, a random sampling in 30 places was done. Frequency of consumption was obtained with informed consent of participants of 253 surveys that considered gender (56% women and 44% men), age (13 less than 18 years, 218 older than 18 years and 22 older than 60 years) and the average body weight, which was 65.5 kg for women and 72.7 kg for men. RESULTS: Aflatoxins were found in 47% of the 30 samples. The estimated daily consumption among women was 21 g of popcorn daily with 2.8 ng kg-1 body weight aflatoxin B1 (AFB1) and 18.29 ng kg-1 body weight total aflatoxins, and for men, the values were 3.0 ng kg-1 body weight AFB1, and 16.0 ng kg-1 body weight of total AF; 1 ng kg-1 body weight is recommended as the tolerance limit by the JECFA (2001). CONCLUSION: The highest liver cancer risk was detected in men population under 18 years of age, with 0.137 cases in 100,000 persons. The results show that 9.5% of the consumers of AFB1-contaminated popcorn are at risk, and 52.2% are at risk for total aflatoxin exposure. Popcorn is accessible to children with lower weight, increasing the risk.

Cellular, physiological and molecular approaches to investigate the antifungal and anti-aflatoxigenic effects of thyme essential oil on Aspergillus flavus.

Several approaches, including the detection of apoptotic-like cell death, aflatoxin B1 (AFB1) production and gene expression analysis, were carried out to provide insights into the antifungal and anti-aflatoxigenic effects of thyme essential oil (EO) on Aspergillus flavus. At 0.5 µL mL-1, thyme EO completely inhibited A. flavus growth. Furthermore, this antifungal activity triggered significant apoptosis, via nuclear condensation (87.5% of nuclei analyzed) and plasma membrane damage (in 100% of treated hyphae). Further analysis of AFB1 production and gene expression related to secondary metabolism (laeA) and the mechanism of virulence (lipA and meT) of A. flavus in the presence of thyme EO indicated important physiological changes related to its anti-aflatoxigenic property. These results highlight the potent antifungal abilities of thyme EO in controlling A. flavus and AFB1 production, especially the abilities that operate by exerting changes at the molecular level and inducing significant apoptotic-like cell death.

Presence of unreported carcinogens, Aflatoxins and their hydroxylated metabolites, in industrialized Oaxaca cheese from Mexico City.

Aflatoxins (AFs) are toxic secondary metabolites of the fungi Aspergillus flavus, A. parasiticus and A. nomius. The fungi produce these AFs in cereals, oilseeds and spices. AFs have damaging effects on all organisms, including humans, and their symptoms can be classified as acute (vomiting, hemorrhage and death) or chronic (immunodepression, Reye syndrome, Kwashiorkor, teratogenesis, hepatitis, cirrhosis, and various cancers). Basic AFs (AFB1, AFB2, AFG1, and AFG2) are metabolized in the liver or by microbes that produce hydroxylated metabolites (AFM1, AFM2, and AFP1) and aflatoxicol (AFL), soluble in water and easy to dispose. Thus, AFs can be excreted in fluids, such as milk. AFs are not destroyed in the process of making cheese. The purpose of this study was to identify and quantify the AFs present in 30 samples of industrialized Oaxaca-type cheese sold in Mexico City. The average concentrations of AFs detected in the 30 samples of industrialized cheese were as follows: AFB1 (0.1 µg kg-1) in 20% (6/30); a trace amount of AFB2 (0.01 < LOD) in only 3% (1/30); AFG1 (0.14 µg kg-1) in 10% (3/30); AFG2 (0.6 µg kg-1) in 30% (9/30); AFM1 (1.7 µg kg-1) in 57% (17/30); AFP1 (0.03% µg kg-1) in 3% (1/30); and AFL (13.1 µg kg-1) in 97% (29/30). AFB1 and AFL were the most abundant aflatoxins in Oaxaca-type cheese. However, eight aflatoxins were present, contributing an average of 15.7 µg kg-1 AFs distributed among the 30 samples. The risk assessment analysis showed that there was no substantial risk for cancer due to AFs in industrialized Oaxaca cheese from Mexico City.

Assessment of Aflatoxin M1 and M2 exposure risk through Oaxaca cheese consumption in southeastern Mexico.

The present study evaluated the exposure of Southeast Mexican population to Aflatoxin M1 (AFM1) and M2 (AFM2) through the consumption of Oaxaca cheese. The intake of Oaxaca cheese was assessed via a food 7-day dairy questionnaire (N = 1100, 2014 and 2015). Thirty Oaxaca cheeses were randomly sampled, and the origin of the samples was also investigated. AFM1 and AFM2 were quantified by HPLC-FD. The exposure was assessed through the combination of the Probabilistic Density Functions (probabilistic approach). The percentage of the population at risk was calculated through the population exceeding the toxicological reference values (TDI). The risk assessment revealed that the population at higher risk to AFM1 and AFM2 was the children, followed by the adolescents and adult women. To our knowledge, the present study is the first to assess the exposure risk of different age groups of a population to AFM1 and AFM2 through the consumption of cheese.

Aducto-ADN-aflatoxina como biomarcadores de exposición en grupos de riesgo de cáncer de higado / Alotoxin-DNA-adductus as exposure biomarkers in groups at risk for liver cancer

La aflatoxina B1 está entre los más potentes carcinógenos conocidos. La presencia de esta toxina parece ser más frecuente en la orina de personas que han sufrido infecciones por el virus B de la hepatitis. En nuestro trabajo se estudió un grupo de 210 pacientes provenientes del Instituto de Nutrición Salvador Zubirán de México con diagnóstico de hepatitis B y C crónicas, cirrosis viral y alcohólica, y grupos controles. Las muestras de orina fueron procesadas y purificadas con columnas de afinidad y cuantificadas por ELISA y HPLC. Los resultados revelaron que el niel más alto de aflatoxinas obtenido correspondió a los grupos de riesgo de hepatitis B crónica (50 por ciento) seguido por los de cirrosis (26 por ciento) y por último el de hepatitis C (16,6 por ciento). Estos resultados apoyan la validez de los aductos alfatoxina-ADN como un buen biomarcador de la expresión de este cancerígeno y su importancia en relación con las enfermedades hepáticas estudiadas

Aducto-ADN-aflatoxina como biomarcadores de exposición en grupos de riesgo de cáncer de higado / Alotoxin-DNA-adductus as exposure biomarkers in groups at risk for liver cancer

La aflatoxina B1 está entre los más potentes carcinógenos conocidos. La presencia de esta toxina parece ser más frecuente en la orina de personas que han sufrido infecciones por el virus B de la hepatitis. En nuestro trabajo se estudió un grupo de 210 pacientes provenientes del Instituto de Nutrición Salvador Zubirán de México con diagnóstico de hepatitis B y C crónicas, cirrosis viral y alcohólica, y grupos controles. Las muestras de orina fueron procesadas y purificadas con columnas de afinidad y cuantificadas por ELISA y HPLC. Los resultados revelaron que el niel más alto de aflatoxinas obtenido correspondió a los grupos de riesgo de hepatitis B crónica (50 por ciento) seguido por los de cirrosis (26 por ciento) y por último el de hepatitis C (16,6 por ciento). Estos resultados apoyan la validez de los aductos alfatoxina-ADN como un buen biomarcador de la expresión de este cancerígeno y su importancia en relación con las enfermedades hepáticas estudiadas(AU)