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1.
Ecol Food Nutr ; 59(3): 243-262, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31778086

RESUMO

The study aimed to quantify the immediate effects of dietary diversification, food safety, and hygiene interventions on child undernutrition in four rural villages in Kongwa district of central Tanzania. One hundred mothers with their children of less than 24 months old were recruited for this study. The difference-in-difference (DID) method was used to assess the effects of intensive intervention through a learning-by-doing process on the topic of aflatoxin free diversified food utilization and improved hygiene practices. Periodic anthropometric measurements were conducted on the 0th, 7th, 14th, and 21st days, and DID estimator showed the significant and positive average marginal effects of the intervention on Z-Scores being 0.459, 0.252, and 0.493 for wasting, stunting, and underweight, respectively. Notably, at the end of the study, the mean aflatoxin M1 level in urine samples decreased by 64% in the intervention group, while it decreased by 11% in the control group. The study provides quantitative evidence on intensive 21-day training for mothers incorporating integrated technologies yielded positive impacts on their children's nutritional outcomes.


Assuntos
Aflatoxinas/urina , Dieta/normas , Higiene/normas , Transtornos da Nutrição do Lactente/prevenção & controle , Fenômenos Fisiológicos da Nutrição do Lactente , Mães/educação , Feminino , Humanos , Lactente , Masculino , Micronutrientes/administração & dosagem , Estado Nutricional , População Rural , Tanzânia/epidemiologia
2.
Biomarkers ; 23(2): 131-136, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28114823

RESUMO

PURPOSE: To determine levels of urinary aflatoxin M1 (AFM1) in children and correlate the concentrations with previously reported aflatoxin albumin adduct (AF-alb) levels in these children. MATERIALS AND METHODS: Matched urine and blood samples were collected from 84 Tanzanian children aged 6-14 months old. From 31 children in one village (Kigwa), samples were collected at three time points six months apart. Samples were collected from 31 and 22 children from two different regions at the second time point only. Urinary AFM1 was measured using a commercial enzyme-linked immunosorbent assay (ELISA) kit with a modified protocol to improve sensitivity. AF-alb was measured using an established ELISA method. RESULTS: The relative ranking of the three villages for exposure to aflatoxin based on either AFM1 or AF-alb biomarker measurements was the same. In Kigwa village, both AFM1 and AF-alb levels were higher at six months post-harvest compared to baseline. However, at the next visit, the AFM1 levels dropped from a GM (interquartile range) of 71.0 (44.7, 112.6) at visit two to 49.3 (31.5, 77.3) pg/ml urine, whereas AF-alb levels increased from 47.3 (29.7, 75.2) to 52.7 (35.4, 78.3) pg/mg albumin between these two visits, reflecting the fact that AFM1 measures short-term exposure, whereas AF-alb measures longer term exposure. There was a correlation between AFB1 intake and AFM1 excretion (r= 0.442, p ≤ 0.001). CONCLUSIONS: Urinary AFM1 is a good biomarker for AFB1 exposure in Tanzanian children, reflecting geographical and temporal variations in exposure to this foodborne toxin.


Assuntos
Aflatoxina M1/urina , Aflatoxinas/urina , Biomarcadores/urina , Contaminação de Alimentos/análise , Aflatoxina M1/sangue , Aflatoxinas/sangue , Albuminas , Biomarcadores/sangue , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Humanos , Lactente , Tanzânia , Zea mays
3.
Public Health Nutr ; 21(6): 1156-1166, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29338801

RESUMO

OBJECTIVE: The present study examined the impacts of training on nutrition, hygiene and food safety designed by the Nutrition Working Group, Child Survival Collaborations and Resources Group (CORE). DESIGN: Adapted from the 21d Positive Deviance/Hearth model, mothers were trained on the subjects of appropriate complementary feeding, water, sanitation and hygiene (WASH) practices, and aflatoxin contamination in food. To assess the impacts on child undernutrition, a randomised controlled trial was implemented on a sample of 179 mothers and their children (<2 years old) in two districts of Malawi, namely Mzimba and Balaka. Settings A 21d intensive learning-by-doing process using the positive deviance approach. SUBJECTS: Malawian children and mothers. RESULTS: Difference-in-difference panel regression analysis revealed that the impacts of the comprehensive training were positive and statistically significant on the Z-scores for wasting and underweight, where the effects increased constantly over time within the 21d time frame. As for stunting, the coefficients were not statistically significant during the 21d programme, although the level of significance started increasing in 2 weeks, indicating that stunting should also be alleviated in a slightly longer time horizon. CONCLUSIONS: The study clearly suggests that comprehensive training immediately guides mothers into improved dietary and hygiene practices, and that improved practices take immediate and progressive effects in ameliorating children's undernutrition.


Assuntos
Ciências da Nutrição Infantil/educação , Educação em Saúde/métodos , Transtornos da Nutrição do Lactente/epidemiologia , Transtornos da Nutrição do Lactente/prevenção & controle , Mães/educação , Adulto , Aflatoxinas/urina , Características da Família , Feminino , Inocuidade dos Alimentos , Humanos , Lactente , Recém-Nascido , Malaui , Masculino , Desnutrição/epidemiologia , Desnutrição/prevenção & controle , Síndrome de Emaciação/epidemiologia , Síndrome de Emaciação/prevenção & controle
4.
Afr Health Sci ; 23(2): 81-87, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38223595

RESUMO

Background: Aflatoxin B1causes damage to the DNA by the alkylation of bases and P53 mutation. Exposure to this mycotoxin is associated with the development of liver cancer. Measures to reduce grain and cereal contamination have been a focus however, the effects of these measures are still lagging behind and exposure continues to occur even in populations at risk of developing liver cancer. Objective: To quantify aflatoxin B1 exposure in a population of HIV infected patients with and without HCC. Method: This was a cross-sectional study among 196 patients with HIV and or HCC. We evaluated the exposure to aflatoxin B1 using the Aflatoxin M1 metabolite by ELISA on urine samples. Results: A total of 196 participants consisting of 163 (83.2%) HIV positive and 28 (14.3%) HCC. Mean age is 46.64±10.8 years. The median aflatoxin (IQR) aflatoxin M1level is 177.3(112.5-272) pg/ml. Only 8(4.1%) of the participant had no exposure to aflatoxin B1. The median (IQR) aflatoxin for fibrosis score ≥ 13kpa (178.7(112.9-286.8) pg/ml) VS < 13kpa (173.5(107.9-250.4)), p = 0.046. Conclusion: There is high prevalence of aflatoxin B1 exposure in this population. Concerted efforts must be put in place to mitigate exposure because of the potential effects of short- and long-term exposure to aflatoxin.


Assuntos
Aflatoxinas , Carcinoma Hepatocelular , Infecções por HIV , Neoplasias Hepáticas , Humanos , Adulto , Pessoa de Meia-Idade , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/genética , Aflatoxinas/toxicidade , Aflatoxinas/urina , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/genética , Aflatoxina B1/toxicidade , Aflatoxina B1/metabolismo , Nigéria/epidemiologia , Estudos Transversais , Infecções por HIV/epidemiologia
5.
Anal Bioanal Chem ; 401(9): 2831-41, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21892639

RESUMO

Humans and animals can be simultaneously exposed through the diet to different mycotoxins, including aflatoxins, ochratoxin A, deoxynivalenol, zearalenone, and fumonisins, which are the most important. Evaluation of the frequency and levels of human and animal exposure to these mycotoxins can be performed by measuring the levels of the relevant biomarkers in urine. Available data on the toxicokinetics of these mycotoxins in animals suggest that aflatoxin M(1) (AFM(1)), ochratoxin A (OTA), deoxynivalenol (DON)/de-epoxydeoxynivalenol (DOM-1), alpha-zearalenol (α-ZOL)/beta-zearalenol (ß-ZOL), and fumonisin B(1) (FB(1)) can be used as urinary biomarkers. A liquid chromatographic-tandem mass spectrometric method has been developed for simultaneous determination of these mycotoxin biomarkers in human or animal urine. Urine samples were purified and concentrated by a double cleanup approach, using a multitoxin immunoaffinity column and a reversed-phase SPE Oasis HLB column. Separation of the biomarkers was performed by reversed-phase chromatography using a multi-step linear methanol-water gradient containing 0.5% acetic acid as mobile phase. Detection and quantification of the biomarkers were performed by triple quadrupole mass spectrometry (LC-ESI-MS/MS). The clean-up conditions were optimised to obtain maximum analyte recovery and high sensitivity. Recovery from spiked samples was performed at four levels in the range 0.03-12 ng mL(-1), using matrix-matched calibration curves for quantification. Mean recoveries of the biomarkers tested ranged from 62 to 96% with relative standard deviations of 3-20%. Enzymatic digestion with ß-glucuronidase/sulfatase resulted in increased concentrations of the biomarkers, in both human and pig urine, in most samples containing measurable concentrations of DON, DOM-1, OTA, α-ZOL, or ß-ZOL. A highly variable increase was observed between individuals. Co-occurrence of OTA and DON in human urine is reported herein for the first time.


Assuntos
Biomarcadores/urina , Cromatografia Líquida de Alta Pressão/métodos , Micotoxicose/urina , Micotoxinas/urina , Espectrometria de Massas em Tandem/métodos , Adulto , Aflatoxinas/urina , Idoso , Idoso de 80 Anos ou mais , Animais , Cromatografia de Fase Reversa , Feminino , Fumonisinas/urina , Glucuronidase/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Micotoxicose/diagnóstico , Ocratoxinas/urina , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Suínos , Tricotecenos/urina , Zeranol/análogos & derivados , Zeranol/urina
6.
Bull Environ Contam Toxicol ; 87(1): 6-10, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21553028

RESUMO

This was a screening study that aimed to determine the presence of nephrotoxic mycotoxins in urine samples from patients with chronic kidney disease of uncertain etiology in the North Central Province of Sri Lanka. The percentage detection of aflatoxins, ochratoxins and fumonisins in 31 patients were 61.29%, 93.5% and 19.4%, respectively. Geometric means of urinary aflatoxins and ochratoxins were 30.93 creatinine and 34.62 ng/g creatinine in chronic kidney disease of uncertain etiology stage 1-2 patients and 84.12 ng/g creatinine and 63.52 ng/g creatinine in unaffected relatives of patients. In chronic kidney disease of uncertain etiology stage 3-5 patients, geometric means of urinary aflatoxins and ochratoxins were 10.40 and 17.08 ng/g creatinine, respectively. Non-affected relatives of patients (n = 6) had comparable levels of these mycotoxins, but healthy Japanese individuals (n = 4) had lower levels than in Sri Lanka. The higher detection rate of urinary ochratoxins in Sri Lankans indicates that exposure is common in the region.


Assuntos
Aflatoxinas/urina , Exposição Ambiental/análise , Fumonisinas/urina , Ocratoxinas/urina , Insuficiência Renal Crônica/induzido quimicamente , Adolescente , Adulto , Idoso , Criança , Creatinina/urina , Monitoramento Ambiental/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/etiologia , Sri Lanka , Incerteza , Adulto Jovem
7.
Toxins (Basel) ; 13(8)2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34437441

RESUMO

Analysis of body fluids and tissues of aflatoxin exposed individuals for the presence of aflatoxins and aflatoxin metabolites has emerged as a reliable indicator of exposure and metabolism of aflatoxins. However, current aflatoxin biomarkers are not appropriate for investigating the long-term effects of aflatoxin exposure. In this explorative study, we investigated the analysis of hair as a complementary or alternative matrix for the assessment of biomarkers of long-term aflatoxin exposure. Three groups of guinea pigs were orally dosed with 5 ugkg-1bw-1, 50 ugkg-1bw-1, and 100 ugkg-1bw-1 of AFB1. Urine and hair samples were collected on days 0, 1, 2, 3, 7, 30, 60, and 90 and analysed for AFB1 and AFM1 using UHPLC-MS/MS. AFB1 and AFM1 were detected in 75% and 13.6%, respectively, of the day 1 to day 7 urine samples. AFB1 was detected in hair samples collected from day 3 up to day 60. This is the first report to confirm the deposition of AFB1 in the hair of experimental animals. These findings indicate that hair analysis has the potential to provide an accurate long-term historical record of aflatoxin exposure with potentially important implications for the field of aflatoxin biomarkers.


Assuntos
Aflatoxinas/análise , Aflatoxinas/toxicidade , Aflatoxinas/urina , Biomarcadores/análise , Biomarcadores/urina , Monitoramento Ambiental/métodos , Cabelo/química , Animais , Relação Dose-Resposta a Droga , Cobaias , Modelos Animais , África do Sul , Fatores de Tempo
8.
Toxins (Basel) ; 13(5)2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925470

RESUMO

This case-control study adds to the growing body of knowledge on the medical, nutritional, and environmental factors associated with Nodding Syndrome (NS), a seizure disorder of children and adolescents in northern Uganda. Past research described a significant association between NS and prior history of measles infection, dependence on emergency food and, at head nodding onset, subsistence on moldy maize, which has the potential to harbor mycotoxins. We used LC-MS/MS to screen for current mycotoxin loads by evaluating nine analytes in urine samples from age-and-gender matched NS cases (n = 50) and Community Controls (CC, n = 50). The presence of the three mycotoxins identified in the screening was not significantly different between the two groups, so samples were combined to generate an overall view of exposure in this community during the study. Compared against subsequently run standards, α-zearalenol (43 ± 103 µg/L in 15 samples > limit of quantitation (LOQ); 0 (0/359) µg/L), T-2 toxin (39 ± 81 µg/L in 72 samples > LOQ; 0 (0/425) µg/L) and aflatoxin M1 (4 ± 10 µg/L in 15 samples > LOQ; 0 (0/45) µg/L) were detected and calculated as the average concentration ± SD; median (min/max). Ninety-five percent of the samples had at least one urinary mycotoxin; 87% were positive for two of the three compounds detected. While mycotoxin loads at NS onset years ago are and will remain unknown, this study showed that children with and without NS currently harbor foodborne mycotoxins, including those associated with maize.


Assuntos
Micotoxinas/urina , Síndrome do Cabeceio/urina , Adolescente , Aflatoxinas/efeitos adversos , Aflatoxinas/urina , Estudos de Casos e Controles , Criança , Desenvolvimento Infantil/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Infantil/efeitos dos fármacos , Pré-Escolar , Feminino , Microbiologia de Alimentos , Humanos , Masculino , Micotoxinas/efeitos adversos , Síndrome do Cabeceio/etiologia , Uganda , Zea mays/efeitos adversos , Zea mays/microbiologia , Zeranol/efeitos adversos , Zeranol/análogos & derivados , Zeranol/urina
9.
Mycotoxin Res ; 36(2): 257-266, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32002812

RESUMO

Mycotoxins' exposure by inhalation and/or dermal contact can occur in different branches of industry especially where heavily dusty settings are present and the handling of dusty commodities is performed. This study aims to explore the possible contribution of the occupational exposure to aflatoxins by analysing urine samples for the presence of aflatoxins B1 and M1 and aflatoxin B1-N7-guanine adduct. The study was conducted in 2017 on two groups of volunteers, the workers group, composed by personnel employed in an Italian feed plant (n = 32), and a control group (n = 29), composed by the administrative employees of the same feed plant; a total of 120 urine samples were collected and analysed. A screening method and a quantitative method with high-resolution mass spectrometry determination were developed and fully validated. Limits of detections were 0.8 and 1.5 pg/mLurine for aflatoxin B1 and M1, respectively. No quantitative determination was possible for the adduct aflatoxin B1-N7-guanine. Aflatoxin B1 and its adduct were not detected in the analysed samples, and aflatoxin M1, instead, was found in 14 samples (12%) within the range 1.9-10.5 pg/mLurine. Only one sample showed a value above the limit of quantification (10.5 pg/mLurine). The absence of a statistical difference between the mean values for workers and the control group which were compared suggests that in this specific setting, no professional exposure occurs. Furthermore, considering the very low level of aflatoxin M1 in the collected urine samples, the contribution from the diet to the overall exposure is to be considered negligible.


Assuntos
Aflatoxinas/urina , Contaminação de Alimentos/análise , Espectrometria de Massas/métodos , Adulto , Aflatoxina B1/urina , Aflatoxina M1/urina , Idoso , Humanos , Itália , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Portugal
10.
Food Res Int ; 134: 109210, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32517894

RESUMO

Human biomonitoring is an important tool to assess human exposure to chemicals, contributing to describe trends of exposure over time and to identify population groups that could be under risk. Aflatoxins are genotoxic and carcinogenic food contaminants causing hepatocellular carcinoma, the third leading cause of cancer deaths worldwide. In Portugal, scarce data are available regarding exposure to aflatoxins and no previous study used human biomonitoring data to comprehensively characterize the associated burden of disease. 24 h urine and first-morning urine paired samples were collected by 94 participants and were analyzed by liquid chromatography-tandem mass spectrometry for the quantitative determination of aflatoxins (B1, B2, G1, G2 and M1). Deterministic and probabilistic models were developed to assess the Portuguese exposure to aflatoxins and to estimate the health impact of this exposure, estimating the attributed Disability-Adjusted Life Years (DALYs). Aflatoxins were detected in a maximum of 13% (AFB1), 16% (AFB2), 1% (AFG1), 2% (AFG2) and 19% (AFM1) of the urine samples. Data obtained through the probabilistic approach revealed an estimated mean probable daily intake of 13.43 ng/kg body weight per day resulting in 0.13 extra cases of hepatocellular carcinoma, corresponding to mean annual DALYs of 172.8 for the Portuguese population (10291027 inhabitants). The present study generated for the first time and within a human biomonitoring study, reliable and crucial data to characterize the burden associated to the exposure to aflatoxins of the Portuguese population. The obtained results constitute an imperative support to risk managers in the establishment of preventive policy measures that contribute to ensure public health protection.


Assuntos
Aflatoxinas/administração & dosagem , Aflatoxinas/toxicidade , Adulto , Aflatoxinas/urina , Biomarcadores/urina , Dieta , Feminino , Contaminação de Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Portugal , Adulto Jovem
11.
J Agric Food Chem ; 68(1): 351-357, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31826612

RESUMO

Cereal foods are commonly contaminated with multiple mycotoxins resulting in frequent human mycotoxin exposure. Children are at risk of high-level exposure because of their high cereal intake relative to body weight. Hence, this study aims to assess multimycotoxin exposure in UK children using urinary biomarkers. Spot urines (n = 21) were analyzed for multimycotoxins (deoxynivalenol, DON; nivalenol, NIV; ochratoxin A, OTA; zearalenone, ZEN; α-zearalenol, α-ZEL; ß-zearalenol, ß-ZEL; T-2 toxin, T-2; HT-2 toxin, HT-2; and aflatoxin B1 and M1, AFB1, AFM1) using liquid chromatography-coupled tandem mass spectrometry. Urine samples frequently contained DON (13.10 ± 12.69 ng/mL), NIV (0.36 ± 0.16 ng/mL), OTA (0.05 ± 0.02 ng/mL), and ZEN (0.09 ± 0.07 ng/mL). Some samples (1-3) contained T-2, HT-2, α-ZEL, and ß-ZEL but not aflatoxins. Dietary mycotoxin estimation showed that children were frequently exposed to levels exceeding the tolerable daily intake (52 and 95% of cases for DON and OTA). This demonstrates that UK children are exposed to multiple mycotoxins through their habitual diet.


Assuntos
Biomarcadores/urina , Micotoxinas/urina , Aflatoxinas/urina , Criança , Pré-Escolar , Dieta/efeitos adversos , Exposição Ambiental/efeitos adversos , Feminino , Contaminação de Alimentos/estatística & dados numéricos , Humanos , Masculino , Ocratoxinas/urina , Inquéritos e Questionários , Toxina T-2/análogos & derivados , Toxina T-2/urina , Tricotecenos/urina , Reino Unido , Zearalenona/urina , Zeranol/análogos & derivados , Zeranol/urina
12.
Science ; 171(3971): 584-5, 1971 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-4992832

RESUMO

A new phenolic derivative of aflatoxin B(1), appearing mainly in conjugated form, was identified as the principal urinary metabolite of aflatoxin B(1) in rhesus monkeys. Its identification in human urine might facilitate estimation of aflatoxin exposure in human populations.


Assuntos
Aflatoxinas/metabolismo , Aflatoxinas/urina , Animais , Cromatografia em Gel , Cromatografia por Troca Iônica , Cromatografia em Camada Fina , Exposição Ambiental , Análise de Alimentos , Glucuronatos/urina , Glucuronidase , Haplorrinos , Humanos , Neoplasias Hepáticas/induzido quimicamente , Masculino , Inquéritos Nutricionais , Fenóis/urina , Análise Espectral , Sulfatases , Sulfatos/urina
13.
Int J Mol Sci ; 10(4): 1465-1475, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19468319

RESUMO

The goal of this study was to determine if selected mycotoxins (trichothecenes, aflatoxins, and ochratoxins) could be extracted and identified in human tissue and body fluids from patients exposed to toxin producing molds in their environment. Human urine and methanol extracted tissues and sputum were examined. Trichothecenes were tested using competitive ELISA techniques. Aflatoxins B1, B2, G1, and G2, and ochratoxin A were tested by using immunoaffinity columns and fluorometry. Test sensitivity and specificity were determined. Levels of detection for the various mycotoxins varied from 0.2 ppb for trichothecenes, 1.0 ppb for aflatoxins, and 2.0 ppb for ochratoxins. Trichothecene levels varied in urine, sputum, and tissue biopsies (lung, liver, brain) from undetectable (<0.2 ppb) to levels up to 18 ppb. Aflatoxin levels from the same types of tissues varied from 1.0 to 5.0 ppb. Ochratoxins isolated in the same type of tissues varied from 2.0 ppb to > 10.0 ppb. Negative control patients had no detectable mycotoxins in their tissues or fluids. These data show that mycotoxins can be detected in body fluids and human tissue from patients exposed to mycotoxin producing molds in the environment, and demonstrate which human tissues or fluids are the most likely to yield positive results.


Assuntos
Micotoxinas/análise , Aflatoxinas/análise , Aflatoxinas/urina , Exposição Ambiental , Ensaio de Imunoadsorção Enzimática , Fluorometria , Fungos/metabolismo , Humanos , Micotoxinas/urina , Líquido da Lavagem Nasal/química , Ocratoxinas/análise , Ocratoxinas/urina , Escarro/química , Tricotecenos/análise , Tricotecenos/urina
14.
Mycotoxin Res ; 35(3): 271-278, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30915618

RESUMO

A study was conducted to investigate the frequency and levels of AFM1 and AFM2 in urine from children who attended the emergency service of a pediatric referral hospital in Bogota, Colombia. A survey on the consumption of foods likely to be a source of aflatoxins and on sociodemographic variables was conducted as well. The frequency of AFM1 in urine was found to be 41.7% with an average concentration in positive samples of 16 pg mL-1 ± 10.7 pg mL-1 (range > LOD-48.5 pg mL-1). The presence of AFM1 in the urine was related to the consumption of cereals likely to be contaminated with AFB1, especially corn and rice. No detectable levels of AFM2 were found in any sample. The results show that children's exposure to aflatoxins in Colombia is indeed a problem and should be one of the priorities of the health authorities. Continuous monitoring of aflatoxins in foods should be carried out, in compliance with Colombian regulations, using analytical methods that allow determination and quantification of aflatoxins in different biological and non-biological matrices at trace levels.


Assuntos
Aflatoxina M1/urina , Aflatoxinas/urina , Grão Comestível/química , Contaminação de Alimentos/análise , Adolescente , Biomarcadores/urina , Criança , Pré-Escolar , Colômbia , Estudos Transversais , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pesquisa Qualitativa , Inquéritos e Questionários
15.
Carcinogenesis ; 29(2): 411-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18192689

RESUMO

To evaluate the efficacy of green tea polyphenols (GTPs) in modulating aflatoxin B(1) (AFB(1)) biomarkers, a total of 352 serum samples and 352 urine samples collected from a 3 month chemoprevention trial with 500 mg GTPs, 1000 mg GTPs and a placebo were measured for AFB(1)-albumin adducts (AFB-AA), aflatoxin M(1) (AFM(1)) and aflatoxin B(1)-mercapturic acid (AFB-NAC). Levels of AFB-AA at baseline were comparable for all three dose groups (P = 0.506). No significant differences were observed in AFB-AA levels in the placebo group over the 3 month period (P = 0.252). However, a significant reduction in AFB-AA levels was observed in the 500 mg group (P = 0.002). A marginally significant reduction in AFB-AA levels was also found in the 1000 mg group over the 3 month intervention period (P = 0.051). An analysis using a mixed-effects model indicated that the reduction in AFB-AA levels over time was dose and time dependent (dose-time interaction P = 0.049). There were no significant differences in median AFM(1) levels among the three study groups at the baseline (P = 0.832), 1 month (P = 0.188) and 3 months (P = 0.132) of the GTP intervention; however, reduction of 42 and 43% in median AFM(1) levels, as compared with the placebo, were found in 500 mg (P = 0.096) and 1000 mg (P = 0.072) groups at 3 months of the intervention. Significant elevations in median AFB-NAC levels and the ratio of AFB-NAC:AFM(1) were found in both 500 and 1000 mg groups compared with the placebo group at both 1 month (P < 0.001) and 3 months (P < 0.001) of GTPs intervention. These results demonstrate that GTPs effectively modulate AFB(1) metabolism and metabolic activation.


Assuntos
Aflatoxinas/sangue , Aflatoxinas/farmacologia , Aflatoxinas/urina , Anticarcinógenos/farmacologia , Biomarcadores , Flavonoides/química , Fenóis/química , Adulto , Quimioprevenção , Feminino , Flavonoides/farmacologia , Humanos , Masculino , Modelos Biológicos , Fenóis/farmacologia , Placebos , Polifenóis , Radioimunoensaio/métodos , Chá , Fatores de Tempo
16.
Food Chem Toxicol ; 46(2): 519-26, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17920747

RESUMO

Aflatoxins are a major risk factor for hepatocellular carcinoma (HCC), and thus understanding the pattern of aflatoxin exposure in different regions is important in order to develop targeted intervention strategies. Given the early onset of HCC in many countries early life exposures may be important. This study investigated aflatoxin exposure in Egyptian children (n=50, aged 1-2.5 years) by assessing urinary aflatoxin metabolite (AFM(1), AFB(1), AFB(2), AFG(1), AFG(2)) levels. Samples from Guinean children (n=50, aged 2-4 years) were analyzed in parallel providing a comparison to a region of established frequent aflatoxin exposure. Aflatoxins were isolated from urine using C18-cartridges followed by immunoaffinity clean-up, and quantified by HPLC with fluorescence detection. Overall aflatoxins were less frequently present in Egyptian (38%) than Guinean urine samples (86%) (p<0.001), which was particularly related to differences in detection rates of AFM(1) (8% compared to 64%, respectively, (p<0.001)). For AFM(1) the geometric mean level in Guinea (16.3 pg/ml; 95% CI: 10.1, 26.6 pg/ml) was 6-fold higher (p<0.001) than in Egypt (2.7 pg/ml; 95% CI: 2.5, 2.8 pg/ml). Urinary aflatoxins from healthy children in these two regions have not previously been reported, and exposure appears modest in Egypt compared to Guinea. These data suggest that measures to reduce aflatoxin exposure in both regions are important, though particularly in Guinea.


Assuntos
Aflatoxinas/urina , Leite Humano/química , Venenos/urina , Aflatoxinas/metabolismo , Biomarcadores , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Estudos Transversais , Egito , Feminino , Guiné , Vírus da Hepatite B/isolamento & purificação , Humanos , Lactente , Masculino , Venenos/metabolismo , Saúde da População Rural
17.
Rev Iberoam Micol ; 25(1): 7-11, 2008 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-18338920

RESUMO

This study investigates the occurrence of aflatoxins in Ecuador. Early investigators proved the presence of aflatoxins in human and animal food, but the disturbing data lead to the formation of two research teams at Guayaquil University and the Agrarian University of Ecuador to investigate aflaxotins and other mycotoxins in food and their relationship to human health. Because the concept of mycotoxicosis as a result of the secondary metabolites produced by different species of moulds could cause different clinical patterns, the research team includes Aspergillus metabolites found in the urine of a patient with pulmonary aspergilloma. We considered that the body itself could create secondary metabolites. An ELISA method was used to detect mycotoxins with the specific reactive compounds using a company base assay. This allows the detection quantitative of such metabolites in 24 h collected urine. The patient was treated with itraconazole for nine months, after clinical, radiological and aflatoxins testing. We also investigated three other cases in children with a second level of malnutrition and only with vomitoxins results and in three investigated cases of otomycosis caused by Aspergillus niger only in one case traces of aflatoxins were found.


Assuntos
Contaminação de Alimentos , Micotoxicose/epidemiologia , Micotoxinas/toxicidade , Adulto , Aflatoxinas/toxicidade , Aflatoxinas/urina , Aspergilose/complicações , Aspergilose/urina , Criança , Pré-Escolar , Equador/epidemiologia , Feminino , Contaminação de Alimentos/estatística & dados numéricos , Gastrite/complicações , Humanos , Pneumopatias Fúngicas/complicações , Pneumopatias Fúngicas/microbiologia , Pneumopatias Fúngicas/urina , Masculino , Desnutrição/complicações , Pessoa de Meia-Idade , Micotoxicose/etiologia , Micotoxicose/urina , Micotoxinas/análise , Micotoxinas/farmacocinética , Otite Média/complicações , Otite Média/microbiologia , População Rural , Tricotecenos/urina , Zearalenona/toxicidade , Zearalenona/urina
18.
J Anal Toxicol ; 31(3): 150-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17579962

RESUMO

Automated immunoaffinity solid-phase extraction followed by liquid chromatography-tandem mass spectrometry and chemical analogue internal standardization is employed to detect and quantify the aflatoxins AFB(1), AFB(2), AFG(1), AFG(2), and the metabolites AFM(1) and AFP(1) in urine. The dynamic range of the method is nearly three orders of magnitude with limits of detection in the low femtogram on column range. The method was validated over a 12-day period by eight analysts. This method is suitable for agricultural, forensic, and public health laboratories during an accidental outbreak or a chemical terrorism event where a rapid and accurate diagnosis of aflatoxicosis is needed.


Assuntos
Aflatoxinas/urina , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Aflatoxina B1/urina , Aflatoxina M1/urina , Aflatoxinas/metabolismo , Animais , Biotransformação , Masculino , Ratos , Ratos Endogâmicos F344 , Reprodutibilidade dos Testes
19.
J Anal Toxicol ; 41(8): 698-707, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28985321

RESUMO

Mycotoxins negatively impact animal health. Aflatoxins (AFs) are the most common mycotoxins affecting both large and small animals and are a common cause of toxin-related pet food recalls. Definitive diagnosis of aflatoxicosis is constrained by a lack of validated ante-mortem analytical methods for detection and quantitation of AFs and their metabolites in biological specimens. Herein, we developed and evaluated a urine-based quantitative method for measurement of aflatoxin B1 (AFB1) and its metabolites aflatoxin M1 (AFM1) and aflatoxin Q1 (AFQ1) in animal urine. (Some of the results have been presented at 59th AAVLD conference, Greensboro, North Carolina, October 13-19th, 2016.) This method uses an immuno-affinity column for clean-up and pre-column derivatization followed by high performance liquid chromatography analysis with fluorescence detection. The method has high selectivity, recovery (>81%) and sensitivity with an instrument limit of detection of 0.20-1.02 pg; instrument limit of quantitation of 0.77-4.46 pg; and a method lower limit of quantitation of 0.30-2.5 ng/mL. The method has high accuracy, repeatability, and is rugged against minor changes. However, because of poor sensitivity of AFQ1 at low concentrations we recommend this method for quantitative determination of AFB1 and AFM1, and for qualitative measurement of AFQ1 in animal urine for diagnosis of aflatoxicosis.


Assuntos
Aflatoxinas/urina , Aflatoxina B1/urina , Aflatoxina M1/urina , Animais , Cromatografia Líquida de Alta Pressão , Fluorescência , Urinálise
20.
Toxins (Basel) ; 9(4)2017 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-28338636

RESUMO

Feed mill workers may handle or process maize contaminated with aflatoxins (AFs). This condition may lead to an unacceptable intake of toxins deriving from occupational exposure. This study assessed the serological and urinary levels of AFs in workers exposed to potentially contaminated dusts in two mills. From March to April 2014, blood and urine samples were collected, on Monday and Friday morning of the same working week from 29 exposed workers and 30 non-exposed controls. AFs (M1, G2, G1, B1, B2) and aflatoxicol (AFOH) A were analyzed. Each subject filled in a questionnaire to evaluate potential food-borne exposures to mycotoxins. AFs contamination in environmental dust was measured in both plants. No serum sample was found to be positive. Seventy four percent of urine samples (73.7%) revealed AFM1 presence. AFM1 mean concentration was 0.035 and 0.027 ng/mL in exposed and non-exposed workers, respectively (p = 0.432); the concentration was slightly higher in Friday's than in Monday's samples, in exposed workers, 0.040 versus (vs.) 0.031 and non-exposed controls (0.030 vs. 0.024, p = 0.437). Environmental AFs contamination ranged from 7.2 to 125.4 µg/kg. The findings of this study reveal the presence of higher AFs concentration in exposed workers than in non-exposed controls, although these differences are to be considered consistent with random fluctuations.


Assuntos
Aflatoxinas/urina , Exposição Ocupacional/análise , Adulto , Aflatoxinas/sangue , Idoso , Ração Animal , Dieta , Poeira , Monitoramento Ambiental , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Zea mays
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