Browsing by Author "Alvito, P."
Now showing 1 - 10 of 22
Results Per Page
Sort Options
- 4th International Conference on Food Contaminants (ICFC) 2021: Challenges on early-life exposure: Book of abstractsPublication . Vasco, E.; Martins, C.; Serrenho, I.; Assunção, R.; Alvito, P.(...) Exposure to hazardous chemicals during first 1000 days of life has been linked to an increased risk of a number of health disorders.There is growing evidence that early-life exposure to chemical hazards can lead to non-communicable diseases (NCDs) in adulthood including cancer, diabetes, obesity and auto-immune diseases. Because cells are rapidly dividing and organ systems are developing during childhood and adolescence, exposure to carcinogens during these early life stages is a major risk factor for cancer later in life. Exposure during early-life due to food ingestion of toxic chemicals seems to have a critical role on the rapid epidemiological rise of obesity as well as a trans-generational transmission of risk of later obesity. Some reports provide evidence of a link between early-life adverse events (ELAE)-induced intestinal barrier disruption, inflammation, epigenetic modifications, and the occurrence of late metabolic disorders (MD), including obesity and type 2 diabetes (T2D). Changes in neurobehavior, sexual development, the prevalence of asthma and allergy, among others, have shown to be associated with chemical contaminants exposure at early-life stages. Early-life is a critical sensitive window of susceptibility. Therefore, this conference will aim to gather research scientists, health and food professionals, regulatory entities, and students to discuss different perspectives on this particular period of life in order to debate i) the risks associated with exposing vulnerable populations to chemicals, in particular, food contaminants and ii) toxic effects of early-life exposure to chemicals. This conference is promoted within the framework of the earlyMYCO national project, funded by the Foundation for Science and Technology (FCT), Portugal, aiming to assess the impact of early-life exposure to mycotoxins and their potential impact on human health. (...)
- Aflatoxin B1 and early life gut microbiota: preliminary results under earlyMYCO projectPublication . Silva, I.; Duarte, E.L.; Bastos-Amador, P.; Ferreira, M.; Alvito, P.; Assunção, R.; Salvador, C.; Caldeira, A.TAflatoxin B1 (AFB1) produces acute or chronic deleterious health effects in humans and animals. Still, long-term effects derived from initial exposure in early-life, a critical period for colonization and development of gut microbiota, has not been fully evaluated, . particularly, effects on gut microbiota and immunity system. This study, performed under the earlyMYCO project, investigated the impact of maternal exposure to AFB1 on early-life microbiota in a mouse model. Females were fed jelly pellets containing 400 µg/kg AFB1 diluted in DMSO (treated animals n=6) or DMSO vehicle alone (control group n=6) during pregnancy and lactation. Faeces from the offspring were collected immediately after weaning and faecal DNA was extracted and purified. Bacterial taxa diversity and relative abundance were assessed by High-Throughput Sequencing performed in an Illumina Miseq® sequencer, targeting the V3 and V4 regions of the 16S rRNA gene. Operational taxonomic units (OTUs) were determined by clustering reads to 16S reference databases. A hundred and twenty-four (N=124) bacterial genera were found in both groups, 5 were only present in AFB1 treated group and 27 exclusively in control groups. A hundred and fifty-one (N=151) bacterial species were common to both groups, 15 species exclusively found in AFB1 litters and 34 species were exclusively found in control litters. Although present in both groups, Akkermansia muciniphila and Bacteroides acidifaciens were significantly higher in controls. A. muciniphila colonizes the intestinal tract in childhood and regulates mucus thickness, intestinal barrier integrity and is involved in immune modulation. B. acidifaciens participates in the metabolism of lipids and sugars and activates some cytokines and immune cell receptors. Sulfidogenic bacteria, recently related to inflammatory bowel disease, such as Desulfovibrio piger and Bilophila wadsworthia were exclusivly found in the treated litters. Early-life gut microbiome triggers the gut immune defences, but is far less stable than the adult microbiome. These preliminary results open an extensive field to further investigate the association between mycotoxins and microbiome, as the latest is increasingly recognized as a major player in a wide spectrum of diseases.
- Are Portuguese population exposed to Zearalenone? A human biomonitoring study as a contribution to the risk assessment of an endocrine disruptorPublication . Martins, Carla; Vidal, A.; De Saeger, Sarah; Assunção, R.; Nunes, Carla; Torres, D.; Goios, A.; Lopes, Carla; Alvito, P.; De Boevre, MartheZearalenone (ZEN) is a mycotoxin that occurs widely in food commodities with particular incidence in cereals. Due to chemical structures similar to the endogenous oestrogen 17-β-estradiol, ZEN and its metabolites exert estrogenic toxicity. Therefore, it is crucial to assess ZEN exposure among the population and biomarker-driven research is a promising method to assess the human exposure. For this reason, ZEN metabolites such as α-zearalenol (α-ZEL), β-zearalenol (β-ZEL), α-zearalenal (α-ZAL), β-zearalenal (β-ZAL), zearalanone (ZAN) (phase I) and the glucuronides ZEN14GlcA, α-ZEL14GlcA and β-ZEL14Glc (phase II) were identified in biological fluids. With a potency factor of 60 relative to ZEN, α-ZEL is the most relevant metabolite in terms of human health. ZEN is characterized by a fast metabolism and excretion, therefore urine is the matrix commonly used to assess the exposure to this mycotoxin and its metabolites. To date, in Portugal, there is a lack of human studies to assess biomarkers of exposure to ZEN. Within the Scope of National Food, Nutrition, and Physical Activity Survey of the Portuguese General Population (2015-2016), 24h-urine samples and non-consecutive dietary assessments (two 24-hour recalls, 8-15 days apart) from 94 participants were included in the present study. Following a salt-assisted matrix extraction, urine samples were analyzed using LC-MS/MS for the simultaneous determination of ZEN, α-ZEL, β-ZEL, α-ZAL, β-ZAL, ZAN and ZEN14GlcA. ZEN and ZEN-14-GlcA were detected in 52% (36/69) and 14% (10/69) of the analyzed samples, with a mean concentration of 1.2 and 6.9 µg/L, respectively. The metabolites α-ZEL, β-ZEL, α-ZAL, β-ZAL, ZAN were not detected in the urine samples. Considering the 24h-urinary volume, the mean dietary excretion of ZEN and ZEN-14-GlcA was 1.5 and 7.8 µg/day, respectively. These data will allow the determination of Probably Daily Intake of zearalenone with more accuracy since it reflects the internal exposure of participants.
- Assessment of mycotoxin exposure and risk characterization using occurrence data in foods and urinary biomarkers in BrazilPublication . Franco, Larissa; Petta, T.; E.Rottinghaus, George; Bordin, Keliani; A.Gomes, Gilmar; Alvito, P.; Assunção, R.; Oliveira, C.This study aimed to assess the exposure of residents (N=86) from rural areas to multiple mycotoxins and characterize the associated risk in two sampling periods (SP) (April–May and December/2016). Mycotoxins in food and urine samples were determined by liquid chromatography coupled to tandem mass spectrometry. Mean probable daily intake (PDI) values based on occurrence data in foods in both SP varied from 0.007 to 0.013, 0.069 to 1.002, 0.119 to 0.321 and 0.013–0.156 μg kg−1 body weight (bw) day−1 for aflatoxins (AFs), deoxynivalenol (DON), fumonisins (FBs) and zearalenone (ZEN), respectively. Mean PDI values based on urinary biomarkers were 0.001, 84.914, 0.031, 0.377 and 0.002 μg kg−1 bw day−1 for AFB1, DON, ochratoxin A (OTA), FB1 and ZEN, respectively. Hazard quotient (HQ) calculated using food data revealed a potential health concern for ZEN in 2nd SP. HQ > 1 based on urinary biomarkers were observed for DON in the two SP. Although OTA was not detected in any food sample, the HQ based on urinary OTA levels was>1 in the 1st SP. Margin of exposure values for AF from food and urine data in the 1st SP were below 10,000, indicating potential health risks.
- Climate change and aflatoxins exposure in Portugal – could we expect a significant health risk?Publication . Assunção, R.; Martins, C.; Viegas, S.; Viegas, C.; Jakobsen, Lea S.; Pires, S.; Alvito, P.In recent decades, changes in climate have caused impacts on natural and human systems on all continents and across the oceans. Climate change (CC) has become one of the most critical issues for the sustainable development of human societies and the functioning of ecosystems on earth. Portugal is highly vulnerable to CC impacts due to its Europe south-western geographical situation, mainly through decreasing annual precipitation, more intense extreme weather and climate events. In fact, CC is considered as one of the biggest global threats to human health of the 21st century and its effects will undoubtedly influence agricultural systems and food safety. Due to the potential impact on the occurrence of food hazards, increased concern has being aroused. Mycotoxins, natural contaminants produced by fungi, are among the most important of such hazards, especially due to their potential to establish deleterious health conditions. From all known mycotoxins, aflatoxins stand to the most toxic for humans. Dietary aflatoxins exposure is considered a significant risk factor for hepatocellular carcinoma (HCC). Considering the impact of CC in mycotoxin contamination of food products available in Portugal, the present study aims to discuss the potential influence of CC in the health risk associated to aflatoxins dietary exposure of Portuguese population. To tackle this objective, the estimated number of hepatocellular carcinoma (HCC) and the associated burden of disease in terms of Disability Adjusted Life Years (DALYs) were derived. Results showed that the number of extra cases of HCC associated to Portuguese aflatoxin dietary exposure ranged from 0.52 and 2.00. The derived DALYs ranged between 8.0 and 30.9. It is expected that in the future the number of DALYs and the associated HCC due to aflatoxin exposure should increase due to CC. These results should represent an alert for the potential consequences of an incompletely explored perspective of CC – the health impact of the human exposure to aflatoxins. Politics and decision-makers should be involved and committed to implement effective measures to deal with CC issues and to reduce its possible consequences.
- Early-life exposure to MYCOtoxins and its impact on health – a case studyPublication . Alvito, P.; Assunção, R.; Bastos-Amador, P.; de Boevre, M.; Duarte, E.; Martins, C.; Serrenho, i.; Silva, I.; Visintin, L.; Ferreira, M.Considering the potential impact on health and the scarce data available regarding early-life exposure to mycotoxins, earlyMYCO project (early-life exposure to MYCOtoxins and its impact on health) proposed to answer key questions: are pregnant women and infants until six months exposed to mycotoxins? Is this exposure a health threat? Does this early-life exposure influence the intestinal immune system development? Which is the burden derived from the exposure to mycotoxins? The earlyMYCO pilot study enrolled 19 pairs of mother and children, with a loss to follow-up ranging between 11% and 47% for different moments of observation. The mycotoxins’ biomarkers detected were AFB1, OTA, DON and bZEL in urine samples (mother and children), and AFB1, aZEL, FB1, FB2 and FB3 in breast milk samples. Food consumption data revealed that foods consumed more frequently during the week were bread, dairy products, non-alcoholic drinks (tea and coffee), animal products (meat and fish) and pasta. Regarding infants, 22% were fed with infant formula and 78% were exclusively breastfed. Considering the exposure levels, a low risk of mothers’ exposure to the main mycotoxins analyzed is expected, since urine samples did not reveal detectable levels of these compounds; however, infants’ urine samples presented a DON mean value of 14.8 ng/mL (corresponding to 148.0 μg/kg bw/day through reverse dosimetry), which could represent a risk for this population group. Notably, maternal exposure to AFB1 promoted an increase of overall T cell population, while it also resulted in a selective reduction of cytokine-producing innate lymphoid cells group 2 (ILC2) population in intestine of the progeny. These alterations were associated with decreased expression of Reg3b and Reg3g by the intestinal mucosa of progeny. Thus, these results indicate that maternal exposure to mycotoxins impacts the development of offspring intestinal immune system. An in vitro approach using intestinal cell lines Caco-2 and Caco-2/HT29-MTX models exposed to AFB1 during 24h, confirmed the deleterious effects of AFB1 on intestinal membrane integrity and its effect on mucus layer. To assess the impact of AFB1 on early-life microbiota, faeces from litters of AFB1 treated female mice and controls were assessed by metagenomics. Although the overall diversity (Shannon diversity index) of the microbiome wasn’t affected between groups, the microbiome composition varied between AFB1 and control faecal samples (Bray–Curtis dissimilarity index). In particular, some beneficial species were diminished in the litters from AFB1 treated females. Results emphasized the need for assessing the prenatal and lactation exposure to mycotoxins.
- Early-life exposure to mycotoxins: assessing the risk under the earlyMYCO projectPublication . Assunção, R.; Martins, C.; Nunes, Baltazar; Silvia, S.; Pires, S.M.; Alvito, P.Exposure to hazardous chemicals during the first 1000 days of life has been associated to a number of health disorders, e.g. non-communicable diseases. A proper risk assessment built on accurate data assumes particular importance to evaluate the potential impact that early-life exposure could represent in adulthood. Mycotoxins, secondary fungal metabolites, could have harmful effects in humans and animals. Recent studies reported that Portuguese young children are exposed to multiple mycotoxins through food consumption which could constitute a health concern [1]. However, earlier exposure to these compounds remains unexplored. earlyMYCO – Early-life exposure to MYCOtoxins and its impact on health, a national funded project (PTDC/MED-TOX/28762/2017), intends to contribute to clarify this issue evaluating the health effects of early-life exposure of Portuguese mother-and-child pairs to mycotoxins and assessing the associated risk. The associated health risk will be characterized and the health impact assessed combining data from mother-and-child pairs, their exposure to mycotoxins and newly obtained toxicological data. The Estimated Daily Intake (EDI) will be compared with reference dose values. Preliminary results of exposure to mycotoxins through food consumption (cereal-based foods) in young children (≤ 3 years old) revealed a potential adverse health effect for percentiles of intake of aflatoxins above or equal to P50 (corresponding to 0.041 ng/kg body weight/day or higher). Additionally, results also suggest that high levels of exposure to mycotoxins in the early life are more related with processed foods than with breastmilk. Obtained results will contribute to reach an accurate risk assessment framework and to establish and prioritize preventive measures to reduce exposure to chemicals and risk, especially for vulnerable population groups as pregnant women and infants. [1] R. Assunção, et. al., Food and Chemical Toxicology 118, 399–408 (2018).
- earlyMYCO – a mother & child cohort in Portugal to assess exposure to mycotoxinsPublication . Martins, C.; Assunção, R.; Serrano, D.; De Boevre, M.; De Saeger, S.; Alvito, P.; Vidigal, C.; Lamy, E.; Nunes, C.Aim: This study aims for the first time in Portugal to assess the early-life exposure to mycotoxins through a mother & child cohort.
- earlyMYCO – a mother & child pilot study to assess early-life exposure to mycotoxins in PortugalPublication . Martins, C.; Assunção, R.; Costa, A.; Serrano, D.; Namorado, S.; Vidigal, C.; Almeida, E.; Alvito, P.; Nunes, C.Early-life exposure occurs during gestation through transfer of toxic substances present in the maternal diet to the fetus and later during lactation, through the breast milk. Mycotoxins are well known carcinogenic, nephrotoxic, hepatotoxic, and immunosuppressive food chemical contaminants. Recently, human biomonitoring data revealed that Portuguese population is exposed to mycotoxins. These results emphasized the need for assessing the prenatal and lactation exposure to mycotoxins in a vulnerable period of life. The earlyMYCO project (PTDC/MED-TOX/28762/2017) aimed, for the first time, to develop and implement a pilot study to assess the early-life exposure to mycotoxins through a mother & child cohort, and to identify the associated challenges, thus contributing to the development of future studies and to the knowledge of the exposome of Portuguese population. Participants were recruited in primary health care units in Lisbon (Portugal) during pregnancy (1st trimester) and followed-up in three moments of observation: 2nd trimester of pregnancy (mother), and 1st and 6th months of the child’s life (mother & child), with the collection of biological samples (blood, urine, breast milk) and the application of sociodemographic and food consumption questionnaires (food frequency and 24h dietary recall). All the participants of the earlyMYCO pilot study (n = 19) reported more than nine years of education, with 37% reporting 10- 12 years and 63% reporting more than 12 years. Regarding the household monthly income, 42% reported a monthly income above 1941€, with most of participants (95%) being workers for remuneration or profit. Dairy products, bread, tea, and coffee were reported as the food items with higher frequency of consumption. The 24h dietary recall questionnaires confirmed these results. Detailed analysis of the data gathered allowed also to highlight the high consumption of meat, fish and vegetables. Regarding infants, 22% were fed with infant formula and 78% were exclusively breastfed. It is expected that results obtained within earlyMYCO pilot study will contribute to a deeper knowledge on exposure of vulnerable population groups (pregnant women and infants) and to the understanding of the impact of early-life exposure to mycotoxins.
- earlyMYCO: assessing the risk associated to the early-life exposure to mycotoxinsPublication . Assunção, R.; Martins, C.; Nunes, B.; Namorado, S.; Silva, S.; Pires, S.M.; Alvito, P.A number of health disorders, e.g. non-communicable diseases, has been associated to exposure with hazardous chemicals during the first 1000 days of life. In this context, a proper risk assessment built on accurate data assumes particular importance to evaluate the potential impact that early-life exposure could represent in adulthood. Mycotoxins are secondary fungal metabolites that could produce harmful effects in humans and animals. These substances can be found in a variety of food products, and recent studies showed that Portuguese young children are exposed to multiple mycotoxins through food consumption which could constitute a health concern in this population group [1]. However, earlier exposure to these compounds remains unexplored. earlyMYCO – Early-life exposure to MYCOtoxins and its impact on health, a national funded project (PTDC/MED-TOX/28762/2017), intends to contribute to clarify this issue evaluating the health effects of early-life exposure of Portuguese mother-and-child pairs to mycotoxins and assessing the associated risk. The associated health risk will be characterized and the health impact assessed combining data from mother-and-child pairs, their exposure to mycotoxins and newly obtained toxicological data. The Estimated Daily Intake (EDI) will be compared with reference dose values. Preliminary results of exposure to mycotoxins through food consumption (cereal-based foods) in young children (≤ 3 years old) revealed a potential adverse health effect for percentiles of intake of aflatoxins above or equal to P50 (corresponding to 0.041 ng/kg body weight/day or higher). When finalized, our results will contribute to reach an accurate risk assessment framework and to establish and prioritize preventive measures to reduce exposure to chemicals and risk, especially for vulnerable population groups as pregnant women and infants. [1] R. Assunção, et. al., Food and Chemical Toxicology 118, 399–408 (2018).
- «
- 1 (current)
- 2
- 3
- »