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1.
Curr Dev Nutr ; 7(2): 100030, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37180082

RESUMO

Background: Inadequate infant and young child feeding (IYCF) practices in low income countries contribute to poor child growth and development. Objectives: To assess IYCF practices and mycotoxin contamination in complementary food ingredients across 2 seasons in Kongwa District, Tanzania. Methods: Early feeding practices in 115 rural households from 25 villages in Kongwa District, Dodoma region, Tanzania, were assessed. The primary caregiver for the index child (6-18 mo of age) was interviewed using a structured dietary questionnaire at recruitment (October/November 2017), and revisited 6 mo later. The questionnaire included questions on typical food consumption in the past 24 h. This study reports 7 of the revised and new IYCF indicators, including minimum dietary diversity (MDD). Aflatoxins (AF) and fumonisins (FUM) were analyzed in complementary food ingredients for pooled household samples to broadly establish patterns of contamination at the village level. Results: The MDD was not met for 80% of infants at recruitment (survey 1) as compared with 56% in survey 2 (P < 0.05). Changes in MDD between the 2 surveys were dependent on season but not age. Maize was consumed by >90% of households in both surveys, whereas groundnut was consumed by 44% and 64% of households in surveys 1 and 2, respectively. AF concentrations in maize and groundnuts were found to be higher in survey 1 than in survey 2. Overall, AF exceeded the legal limit in 18% of maize and 61% of groundnut pooled samples in both surveys. Maize was also contaminated with significant FUM concentrations. Conclusions: Poor diets were common among children in Kongwa District. Reliance on maize and groundnuts exposes this vulnerable age group to AF (also to FUM in maize). Inadequate diet and exposure to AF and FUM have separately been linked to linear growth retardation. Low diet diversity and mycotoxins contamination are plausible causes for poor growth and development among infants in Central Tanzania. Curr Dev Nutr 20XX;x:xx.

2.
Matern Child Nutr ; 19(3): e13499, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36891916

RESUMO

Aflatoxins are toxic secondary metabolites of fungi that colonize staple food crops, such as maize and groundnut, frequently used in complementary feeding. In preparation for a large trial, this pilot study examined if provision of a low-aflatoxin infant porridge flour made from local maize and groundnuts reduced the prevalence of a urinary aflatoxin biomarker in infants. Thirty-six infants aged 6-18 months were included from four villages in Kongwa District, Tanzania. The study was conducted over 12 days with a three-day baseline period and a 10 days where low-AF porridge flour was provided. Porridge intake of infants was assessed using quantitative 24-h recalls by mothers. Household food ingredients used in infant porridge preparation and urine samples were collected on Days 1-3 (baseline) and 10-12 (follow-up). Aflatoxins were measured in household foods, and AFM1 was measured in urine. At baseline and follow-up, 78% and 97%, respectively, of the infants consumed porridge in the previous 24 h, with a median volume of 220 mL (interquartile range [IQR]: 201, 318) and 460 mL (IQR: 430, 563), respectively (p < 0.001). All 47 samples of homemade flour/ingredients were contaminated with AFs (0.3-723 ng/g). The overall prevalence of individuals with detectable urinary AFM1 was reduced by 81%, from 15/36 (42%) at baseline to 3/36 (8%) at follow-up (p = 0.003). Provision of low-aflatoxin porridge flour was acceptable to caregivers and their infants and successfully reduced the prevalence of detectable urinary AFM1 in infants, thus, confirming its potential to be tested in future large-scale health outcomes trial.


Assuntos
Aflatoxinas , Lactente , Feminino , Humanos , Criança , Farinha , Tanzânia , Projetos Piloto , Contaminação de Alimentos/análise , Biomarcadores/urina
3.
Environ Int ; 158: 106996, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34991256

RESUMO

A multi-specimen, multi-mycotoxin approach involving ultra-sensitive LC-MS/MS analysis of breast milk, complementary food and urine was applied to examine mycotoxin co-exposure in 65 infants, aged 1-18 months, in Ogun state, Nigeria. Aflatoxin M1 was detected in breast milk (4/22 (18%)), while six other classes of mycotoxins were quantified; including dihydrocitrinone (6/22 (27%); range: 14.0-59.7 ng/L) and sterigmatocystin (1/22 (5%); 1.2 ng/L) detected for the first time. Seven distinct classes of mycotoxins including aflatoxins (9/42 (21%); range: 1.0-16.2 µg/kg) and fumonisins (12/42 (29%); range: 7.9-194 µg/kg) contaminated complementary food. Mycotoxins covering seven distinct classes with diverse structures and modes of action were detected in 64/65 (99%) of the urine samples, demonstrating ubiquitous exposure. Two aflatoxin metabolites (AFM1 and AFQ1) and FB1 were detected in 6/65 (9%), 44/65 (68%) and 17/65 (26%) of urine samples, respectively. Mixtures of mycotoxin classes were common, including 22/22 (100%), 14/42 (33%) and 56/65 (86%) samples having 2-6, 2-4, or 2-6 mycotoxins present, for breast milk, complementary food and urine, respectively. Aflatoxin and/or fumonisin was detected in 4/22 (18%), 12/42 (29%) and 46/65 (71%) for breast milk, complimentary foods and urine, respectively. Furthermore, the detection frequency, median concentrations and occurrence of mixtures were typically greater in urine of non-exclusively breastfed compared to exclusively breastfed infants. The study provides novel insights into mycotoxin co-exposures in early-life. Albeit a small sample set, it highlights transition to higher levels of infant mycotoxin exposure as complementary foods are introduced, providing impetus to mitigate during this critical early-life period and encourage breastfeeding.


Assuntos
Citrinina , Micotoxinas , Monitoramento Biológico , Biomarcadores , Aleitamento Materno , Criança , Cromatografia Líquida , Feminino , Contaminação de Alimentos/análise , Humanos , Lactente , Leite Humano/química , Nigéria , Espectrometria de Massas em Tandem
4.
Chemosphere ; 287(Pt 2): 132226, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34826919

RESUMO

Exposure to food and environmental contaminants is a global environmental health issue. In this study, innovative LC-MS/MS approaches were applied to investigate mycotoxin co-exposure in mother-infant pairs (n = 23) by analyzing matched plate-ready food, breast milk and urine samples of mothers and their exclusively breastfed infants. The study revealed frequent co-occurrence of two to five mycotoxins. Regulated (e.g. aflatoxins, deoxynivalenol and ochratoxin A) and emerging mycotoxins (e.g. alternariol monomethyl ether and beauvericin) were frequently detected (3 %-89 % and 45 %-100 %), in at least one specimen. In addition, a moderate association of ochratoxin A in milk to urine of mothers (r = 0.47; p = 0.003) and infants (r = 0.52; p = 0.019) but no other significant correlations were found. Average concentration levels in food mostly did not exceed European maximum residue limits, and intake estimates demonstrated exposure below tolerable daily intake values. Infants were exposed to significantly lower toxin levels compared to their mothers, indicating the protective effect of breastfeeding. However, the transfer into milk and urine and the resulting chronic low-dose exposure warrant further monitoring. In the future, occurrence of mycotoxin-mixtures, and their combined toxicological effects need to be comprehensively considered and implemented in risk management strategies. These should aim to minimize early-life exposure in critical developmental stages.


Assuntos
Mães , Micotoxinas , Cromatografia Líquida , Feminino , Contaminação de Alimentos/análise , Humanos , Lactente , Micotoxinas/análise , Nigéria , Espectrometria de Massas em Tandem
5.
Artigo em Inglês | MEDLINE | ID: mdl-34206929

RESUMO

Phthalates, plasticizers ubiquitous in household and personal care products, have been associated with metabolic disturbances. Despite the noted racial differences in phthalate exposure and the prevalence of metabolic syndrome (MetS), it remains unclear whether associations between phthalate metabolites and MetS vary by race and sex. A cross-sectional analysis was conducted among 10,017 adults from the National Health and Nutritional Examination Survey (2005-2014). Prevalence odds ratios (POR) and 95% confidence intervals (CIs) were estimated for the association between 11 urinary phthalate metabolites and MetS using weighted sex and race stratified multivariable logistic regression. Higher MCOP levels were significantly associated with increased odds of MetS among women but not men, and only remained significant among White women (POR Q4 vs. Q1 = 1.68, 95% CI: 1.24, 2.29; p-trend = 0.001). Similarly, the inverse association observed with MEHP among women, persisted among White women only (POR Q4 vs. Q1 = 0.53, 95% CI: 0.35, 0.80; p-trend = 0.003). However, ΣDEHP metabolites were associated with increased odds of MetS only among men, and this finding was limited to White men (POR Q4 vs. Q1 = 1.54, 95% CI: 1.01, 2.35; p-trend = 0.06). Among Black men, an inverse association was observed with higher MEP levels (POR Q4 vs. Q1 = 0.43, 95% CI: 0.24, 0.77; p-trend = 0.01). The findings suggest differential associations between phthalate metabolites and MetS by sex and race/ethnicity.


Assuntos
Poluentes Ambientais , Síndrome Metabólica , Ácidos Ftálicos , Adulto , Estudos Transversais , Exposição Ambiental , Feminino , Humanos , Masculino , Síndrome Metabólica/induzido quimicamente , Síndrome Metabólica/epidemiologia , Inquéritos Nutricionais , Caracteres Sexuais
6.
Toxins (Basel) ; 13(6)2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208182

RESUMO

In the course of assessing the human exposure to mycotoxins, biomarker-based approaches have proven to be important tools. Low concentration levels, complex matrix compositions, structurally diverse analytes, and the large size of sample cohorts are the main challenges of analytical procedures. For that reason, an online solid phase extraction-ultra high-performance liquid chromatography-tandem mass spectrometry (online SPE-UHPLC-MS/MS) method was developed, allowing for the sensitive, robust, and rapid analysis of 11 relevant mycotoxins and mycotoxin metabolites in human urine. The included spectrum of analytes comprises aflatoxin M1 (AFM1), altenuene (ALT), alternariol monomethyl ether (AME), alternariol (AOH), citrinin (CIT) and its metabolite dihydrocitrinone (DH-CIT), fumonisin B1 (FB1), ochratoxin A (OTA), and zearalenone (ZEN) as well as α- and ß-zearalenol (α- and ß-ZEL). Reliable quantitation was achieved by means of stable isotope dilution, except for ALT, AME and AOH using matrix calibrations. The evaluation of method performance displayed low limits of detection in the range of pg/mL urine, satisfactory apparent recovery rates as well as high accuracy and precision during intra- and interday repeatability. Within the analysis of Zimbabwean urine samples (n = 50), the applicability of the newly developed method was shown. In addition to FB1 being quantifiable in all analyzed samples, six other mycotoxin biomarkers were detected. Compared to the occurrence rates obtained after analyzing the same sample set using an established dilute and shoot (DaS) approach, a considerably higher number of positive samples was observed when applying the online SPE method. Owing to the increased sensitivity, less need of sample handling, and low time effort, the herein presented online SPE approach provides a valuable contribution to human biomonitoring of mycotoxin exposure.


Assuntos
Micotoxinas/urina , Monitoramento Biológico , Biomarcadores/urina , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Extração em Fase Sólida , Espectrometria de Massas em Tandem
7.
Sci Rep ; 11(1): 7403, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795755

RESUMO

Colon cancer is one of the leading causes of cancer death worldwide. It is widely believed that environmental factors contribute to colon cancer development. Zearalenone (ZEA) is non-steroidal estrogenic mycotoxin that is widely found in the human diet and animal feeds. Most cancer studies of ZEA focused on estrogen sensitive cancers, while few focused on other types, such as colon cancer; despite the gastrointestinal tract being the first barrier exposed to food contaminants. This study investigated the stimulatory effects of ZEA on colon cancer cell lines and their underlying molecular mechanisms. ZEA promoted anchorage independent cell growth and cell cycle progression through promoting G1-to-S phase transition. Proliferative marker, cyclin D1 and Ki67 were found to be upregulated upon ZEA treatment. G protein-coupled estrogenic receptor 1 (GPER) protein expression was promoted upon ZEA treatment suggesting the involvement of GPER. The growth promoting effect mediated through GPER were suppressed by its antagonist G15. ZEA were found to promote the downstream parallel pathway, MAPK signaling pathway and Hippo pathway effector YAP1. Altogether, our observations suggest a novel mechanism by which ZEA could promote cancer growth and provide a new perspective on the carcinogenicity of ZEA.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Neoplasias do Colo/metabolismo , Estrogênios não Esteroides/administração & dosagem , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Zearalenona/administração & dosagem , Transporte Ativo do Núcleo Celular , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Biomarcadores Tumorais , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/genética , Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Receptores de Estrogênio/genética , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/genética , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAP
9.
Toxins (Basel) ; 13(5)2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33924868

RESUMO

Mycotoxins are toxic secondary fungal metabolites that frequently contaminate cereal crops globally, presenting exposure hazards to humans and livestock in many settings. The heterogeneous distribution of mycotoxins in food restricts the usefulness of food sampling and intake estimates for epidemiological studies, making validated exposure biomarkers better tools for informing epidemiological investigations. While biomarkers of exposure have served important roles for understanding the public health impact of mycotoxins such as aflatoxins (AF), the science of biomarkers must continue advancing to allow for better understanding of mycotoxins' roles in the etiology of disease and the effectiveness of mitigation strategies. This review will discuss mycotoxin biomarker development approaches over several decades for four toxins of significant public health concerns, AFs, fumonisins (FB), deoxynivalenol (DON), and ochratoxin A (OTA). This review will also highlight some knowledge gaps, key needs and potential pitfalls in mycotoxin biomarker interpretation.


Assuntos
Microbiologia de Alimentos , Micotoxinas/toxicidade , Biomarcadores/análise , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Exposição Ambiental/prevenção & controle , Humanos , Micotoxinas/análise
11.
BMC Public Health ; 20(1): 598, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357944

RESUMO

BACKGROUND: The number of stunted children has fallen globally but continues to increase in Africa. Stunting is estimated to contribute to 14-17% of child deaths under 5 years of age and is a risk factor for poor cognitive and motor development and educational outcomes. Inadequate dietary intake and disease are thought to be the immediate causes of undernutrition and stunting. However, improving infant diets through complementary feeding interventions has been shown to only modestly reduce stunting. Multiple observational studies demonstrate a dose response relationship between fetal and post-natal aflatoxin exposure and reduced linear growth. METHODS: This community-based cluster randomized trial will measure the effect of a reduced aflatoxin diet on length-for-age Z scores at 18 months in central Tanzania. All 52 health facilities in the Kongwa District of Dodoma Region were randomized into two groups. Starting at 6 months of age, participants in the intervention group receive a low-aflatoxin pre-blended porridge flour containing maize and groundnut (ratio 4:1 respectively) and low-aflatoxin groundnut flour, whereas in the control group the same porridge mix and groundnut flour are promoted through education but acquired by the household. Both groups will receive the same infant and young child feeding education and a thermos flask. A total of 3120 infants between 6 weeks and 3 months of age will be recruited into the study over 1 year. Data will be collected four times - at recruitment and when the infants are 6, 12 and 18 months of age. In a cohort of 600 infants, additional data will be collected at 9 and 15 months of age. The primary outcome is length-for-age at 18 months. Secondary outcomes include the Z scores for weight-for-age, middle upper arm circumference and head circumference, and the blood biomarker aflatoxin-albumin in the full sample, with the urine biomarker aflatoxin M1 analyzed in the cohort only. DISCUSSION: Better understanding the etiology of childhood stunting can lead to more appropriate interventions and policies to further reduce linear growth faltering and meet the Sustainable Development Goals. TRIAL REGISTRATION: NCT03940547, (April 24, 2019).


Assuntos
Peso Corporal/efeitos dos fármacos , Desenvolvimento Infantil/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Transtornos do Crescimento/induzido quimicamente , Fenômenos Fisiológicos da Nutrição do Lactente/efeitos dos fármacos , Micotoxinas/toxicidade , Pré-Escolar , Estudos de Coortes , Feminino , Transtornos do Crescimento/epidemiologia , Humanos , Lactente , Masculino , Tanzânia/epidemiologia
13.
Sci Rep ; 9(1): 19173, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31844123

RESUMO

Extensive research has revealed the association of continued oxidative stress with chronic inflammation, which could subsequently affect many different chronic diseases. The mycotoxin deoxynivalenol (DON) frequently contaminates cereals crops worldwide, and are a public health concern since DON ingestion may result in persistent intestinal inflammation. There has also been considerable attention over the potential of DON to provoke oxidative stress. In this study, the cytoprotective effect of Schisandrin A (Sch A), one of the most abundant active dibenzocyclooctadiene lignans in the fruit of Schisandra chinensis (Turcz.) Baill (also known as Chinese magnolia-vine), was investigated in HT-29 cells against DON-induced cytotoxicity, oxidative stress and inflammation. Sch A appeared to protect against DON-induced cytotoxicity in HT-29 cells, and significantly lessened the DON-stimulated intracellular reactive oxygen species and nitrogen oxidative species production. Furthermore, Sch A lowered DON-induced catalase, superoxide dismutase and glutathione peroxidase antioxidant enzyme activities but maintains glutathione S transferase activity and glutathione levels. Mechanistic studies suggest that Sch A reduced DON-induced oxidative stress by down-regulating heme oxygenase-1 expression via nuclear factor (erythroid-derived 2)-like 2 signalling pathway. In addition, Sch A decreased the DON-induced cyclooxygenase-2 expression and prostaglandin E2 production and pro-inflammatory cytokine interleukin 8 expression and secretion. This may be mediated by preventing DON-induced translocation of nuclear factor-κB, as well as activation of mitogen-activated protein kinases pathways. In the light of these findings, we concluded that Sch A exerted a cytoprotective role in DON-induced toxicity in vitro, and it would be valuable to examine in vivo effects.


Assuntos
Ciclo-Octanos/farmacologia , Citoproteção , Enterócitos/patologia , Inflamação/patologia , Lignanas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Compostos Policíclicos/farmacologia , Tricotecenos/toxicidade , Catalase/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Morte Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citoproteção/efeitos dos fármacos , Dinoprostona/biossíntese , Enterócitos/efeitos dos fármacos , Enterócitos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Células HT29 , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Inflamação/genética , Mediadores da Inflamação/metabolismo , Interleucina-8/biossíntese , Peroxidação de Lipídeos/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Modelos Biológicos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Nitritos/metabolismo , Estresse Oxidativo/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
14.
J Med Virol ; 91(10): 1882-1886, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31180138

RESUMO

Enteroviral meningitis in infants and children commonly leads to hospital admission. Diagnosing viral meningitis can be difficult clinically. We examined the usefulness of enteroviral polymerase chain reaction (PCR) testing using cerebrospinal fluid (CSF) samples on clinical practice by comparing positive enteroviral CSF PCR cases (n = 39/136) to negative controls using both clinical outcomes and laboratory parameters. A positive result correlated with a reduced admission to high dependency unit, reduced the duration of antibiotics and a shorter length of stay (P < .05). Adjusted CSF white cell count > 5/µL correlated with positive PCR (P < .05) but would have missed 32% of cases of enteroviral meningitis. Following these findings, an algorithm for the management of suspected viral meningitis has been introduced.


Assuntos
Infecções por Enterovirus/diagnóstico , Infecções por Enterovirus/virologia , Enterovirus/isolamento & purificação , Meningite Viral/diagnóstico , Meningite Viral/virologia , Adolescente , Criança , Pré-Escolar , Enterovirus/genética , Feminino , Humanos , Lactente , Masculino
15.
Food Chem Toxicol ; 128: 171-179, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30965105

RESUMO

In order to understand the changes in toxic metabolite profiles in uncooked and cooked foods, samples of flour/grain (n = 40) and their corresponding plate-ready food (n = 39) were collected from 40 households in two states of northern Nigeria. The food samples were analyzed for multiple fungal metabolites by LC-MS/MS and daily intakes of mycotoxins in the diets were estimated and compared to established margin of exposure (MOE) and tolerable daily intake (TDI) values. Both food groups contained 65 fungal and plant metabolites, inclusive of 23 mycotoxins. The mean concentrations of aflatoxin B1, beauvericin, fumonisin B1 (FB1), FB2, FB3, hydrolysed FB1, moniliformin and nivalenol were significantly (p < 0.05) higher in flour than in the plate-ready food samples. The levels of several mycotoxins were higher in the flour samples than in plate-ready meals by 129-383%. The dilution effect from proportionate mixing of flour samples with water led to 48-100% reduction in detectable mycotoxins in flour to plate-ready meals. Aflatoxins and fumonisins co-occurred in 36% of the plate-ready foods. Exposures of households to aflatoxins and fumonisins based on 95% CI concentration of mycotoxins in the meals were high, suggesting potential health risks based on calculated low MOE and exceedence of stipulated TDI value, respectively.


Assuntos
Culinária , Características da Família , Contaminação de Alimentos/análise , Micotoxinas/análise , Venenos/análise , Saúde da População Rural , Adolescente , Adulto , Aflatoxinas/análise , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Cromatografia Líquida , Exposição Dietética , Feminino , Fumonisinas/análise , Humanos , Lactente , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Nigéria , Espectrometria de Massas em Tandem , Adulto Jovem
16.
Environ Health ; 18(1): 7, 2019 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-30634980

RESUMO

BACKGROUND: Neonicotinoids are a class of systemic insecticides widely used on food crops globally. These pesticides may be found in "off-target" food items and persist in the environment. Despite the potential for extensive human exposure, there are limited studies regarding the prevalence of neonicotinoid residues in foods sold and consumed in the United States. METHODS: Residue data for seven neonicotinoid pesticides collected between 1999 and 2015 by the US Department of Agriculture's Pesticide Data Program (PDP) were collated and summarized by year across various food commodities, including fruit, vegetable, meat, dairy, grain, honey, and baby food, as well as water to qualitatively describe and examine trends in contamination frequency and residue concentrations. RESULTS: The highest detection frequencies (DFs) for neonicotinoids by year on all commodities were generally below 20%. Average DFs over the entire study period, 1999-2015, for domestic and imported commodities were similar at 4.5%. For all the samples (both domestic and imported) imidacloprid was the neonicotinoid with the highest overall detection frequency at 12.0%. However, higher DFs were observed for specific food commodity-neonicotinoid combinations such as: cherries (45.9%), apples (29.5%), pears (24.1%) and strawberries (21.3%) for acetamiprid; and cauliflower (57.5%), celery (20.9%), cherries (26.3%), cilantro (30.6%), grapes (28.9%), collard greens (24.9%), kale (31.4%), lettuce (45.6%), potatoes (31.2%) and spinach (38.7%) for imidacloprid. Neonicotinoids were also detected in organic commodities, (DF < 6%). Individual commodities with at least 5% of samples testing positive for two or more neonicotinoids included apples, celery, and cherries. Generally, neonicotinoid residues on food commodities did not exceed US Environmental Protection Agency tolerance levels. Increases in detection trends for both finished and untreated water samples for imidacloprid were observed from 2004 to 2011. CONCLUSIONS: Analysis of PDP data indicates that low levels of neonicotinoids are present in commonly-consumed fruits and vegetables sold in the US. Trends in detection frequencies suggest an increase in use of acetamiprid, clothianidin and thiamethoxam as replacements for imidacloprid. Given these findings, more extensive surveillance of the food and water supply is warranted, as well as biomonitoring studies and assessment of cumulative daily intake in high risk groups, including pregnant women and infants.


Assuntos
Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Inseticidas/análise , Neonicotinoides/análise , Resíduos de Praguicidas/análise , Monitoramento Ambiental , Frutas/química , Estados Unidos , Verduras/química , Água/análise
17.
Anal Chem ; 90(24): 14569-14577, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30449087

RESUMO

Infants are particularly susceptible toward the toxic effects of food contaminants, including mycotoxins. However, multimycotoxin exposure assessment in breast milk has received very limited attention so far, resulting in a poor understanding of coexposures during early life. Here, we present the development and application of a highly sensitive, specific, and quantitative assay assessing up to 28 mycotoxins, including regulated (aflatoxins, ochratoxin A, deoxynivalenol, zearalenone) and emerging mycotoxins as well as key metabolites by LC-MS/MS. After careful optimization of the sample preparation procedure, a QuEChERS protocol combined with a freeze-out step was validated in-house. The limits of quantification varied between 0.009 and 2.9 ng/mL, and for most analytes extraction recovery (74-116%) and intermediate precision (2-20%) were satisfactory. The method was applied to examine multiple breast milk samples obtained from 22 women ( n = 75 in total) from Ogun State, Nigeria. Most samples were either entirely free of mycotoxins or contaminated to a minimal extent with beauvericin (56%), enniatin B (9%), ochratoxin A (15%), and aflatoxin M1 (1%). The most abundant mycotoxin was beauvericin, which was not reported in this biological fluid before, with concentrations up to 0.019 ng/mL. In conclusion, the method demonstrated to be fit for purpose to determine and quantify low background contaminations in human breast milk. On the basis of the high sensitivity of the novel analytical method, it was possible to deduce that tolerable daily intake values were not exceeded by breastfeeding in the examined infants.


Assuntos
Leite Humano/metabolismo , Micotoxinas/análise , Espectrometria de Massas em Tandem , Aflatoxinas/análise , Cromatografia Líquida de Alta Pressão , Humanos , Lactente , Limite de Detecção , Leite Humano/química , Ocratoxinas/análise
18.
Anal Chim Acta ; 1019: 84-92, 2018 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-29625687

RESUMO

There is a critical need to better understand the patterns, levels and combinatory effects of exposures we are facing through our diet and environment. Mycotoxin mixtures are of particular concern due to chronic low dose exposures caused by naturally contaminated food. To facilitate new insights into their role in chronic disease, mycotoxins and their metabolites are quantified in bio-fluids as biomarkers of exposure. Here, we describe a highly sensitive urinary assay based on ultra-high performance liquid chromatography - tandem mass spectrometer (UHPLC-MS/MS) and 13C-labelled or deuterated internal standards covering the most relevant regulated and emerging mycotoxins. Utilizing enzymatic pre-treatment, solid phase extraction and UHPLC separation, the sensitivity of the method was significantly higher (10-160x lower LODs) than in a previously described method used for comparison purpose, and stable isotopes provided compensation for challenging matrix effects. This method was in-house validated and applied to re-assess mycotoxin exposure in urine samples obtained from Nigerian children, adolescent and adults, naturally exposed through their regular diet. Owing to the methods high sensitivity, biomarkers were detected in all samples. The mycoestrogen zearalenone was the most frequently detected contaminant (82%) but also ochratoxin A (76%), aflatoxin M1 (73%) and fumonisin B1 (71%) were quantified in a large share of urines. Overall, 57% of 120 urines were contaminated with both, aflatoxin M1 and fumonisin B1, and other co-exposures were frequent. These results clearly demonstrate the advanced performance of the method to assess lowest background exposures (pg mL-1 range) using a single, highly robust assay that will allow for the systematic investigation of low dose effects on human health.


Assuntos
Micotoxinas/urina , Adulto , Biomarcadores/urina , Isótopos de Carbono , Criança , Cromatografia Líquida de Alta Pressão , Humanos , Masculino , Estrutura Molecular , Nigéria , Espectrometria de Massas em Tandem
19.
Food Chem Toxicol ; 107(Pt A): 10-19, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28599879

RESUMO

Toxins of microbial origin frequently contaminate foodstuffs worldwide and pose a serious hazard to humans. This study reports on LCMS/MS quantification of multiple fungal and bacterial toxins, from household sampling of 50 traditionally prepared maize-fufu samples from Bamunka village, western highlands of Cameroon. Seventy-four metabolites including aflatoxin B1 (AFB1) (12/50: mean 0.9, range n.d-1.8 µg kg-1), cereulide (50/50: mean 37; range 1-236 µg kg-1), deoxynivalenol (DON) (50/50: mean 23, range 14-55 µg kg-1), fumonisin B1 (FB1) (50/50: mean: 151, range 48-709 µg kg-1), nivalenol (NIV) (50/50; mean 268, range 116-372 µg kg-1), patulin (PAT) (15/50:mean 105, range 12-890 µg kg-1) and zearalenone (ZEN) (50/50: mean 49, range 5-150) were detected; and of note every sample contained at least 27 toxic compounds. While individual toxin levels were mostly low there is always concern regarding mixtures, for which data are absent or limited. This study reports several novel observations of toxins not previously reported in maize, and the mixture of toxins, e.g. cereulide, PAT and ZEN derivatives (ZEN-cis and ZENsulfate-cis) are reported for the first time in Cameroonian food.


Assuntos
Toxinas Bacterianas/química , Contaminação de Alimentos/análise , Micotoxinas/química , Zea mays/microbiologia , Adulto , Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Camarões , Feminino , Fungos/metabolismo , Humanos , Masculino , Micotoxinas/metabolismo , Espectrometria de Massas em Tandem , Zea mays/química , Zea mays/metabolismo
20.
Am J Trop Med Hyg ; 96(4): 770-776, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28500823

RESUMO

AbstractPregnant women and their developing fetuses are vulnerable to multiple environmental insults, including exposure to aflatoxin, a mycotoxin that may contaminate as much as 25% of the world food supply. We reviewed and integrated findings from studies of aflatoxin exposure during pregnancy and evaluated potential links to adverse pregnancy outcomes. We identified 27 studies (10 human cross-sectional studies and 17 animal studies) assessing the relationship between aflatoxin exposure and adverse birth outcomes or anemia. Findings suggest that aflatoxin exposure during pregnancy may impair fetal growth. Only one human study investigated aflatoxin exposure and prematurity, and no studies investigated its relationship with pregnancy loss, but animal studies suggest aflatoxin exposure may increase risk for prematurity and pregnancy loss. The fetus could be affected by maternal aflatoxin exposure through direct toxicity as well as indirect toxicity, via maternal systemic inflammation, impaired placental growth, or elevation of placental cytokines. The cytotoxic and systemic effects of aflatoxin could plausibly mediate maternal anemia, intrauterine growth restriction, fetal loss, and preterm birth. Given the widespread exposure to this toxin in developing countries, longitudinal studies in pregnant women are needed to provide stronger evidence for the role of aflatoxin in adverse pregnancy outcomes, and to explore biological mechanisms. Potential pathways for intervention to reduce aflatoxin exposure are urgently needed, and this might reduce the global burden of stillbirth, preterm birth, and low birthweight.


Assuntos
Aflatoxinas/toxicidade , Anemia/induzido quimicamente , Contaminação de Alimentos/análise , Complicações na Gravidez/induzido quimicamente , Resultado da Gravidez , Feminino , Humanos , Gravidez
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