Browsing by Issue Date, starting with "2019-09-27"
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- Dietary exposure of the Portuguese population to aflatoxins, ochratoxin A and patulin based on a Total Diet StudyPublication . Vasco, Elsa; Dias, Maria da Graça; Oliveira, LuísaThe objective of this study is to evaluate, by the Total Diet Study approach, the dietary exposure of the adult Portuguese population to seven mycotoxins (AFB1, AFB2, AFG1, AFG2, AFM1, OTA and PAT) and the risk of exceeding the international health-based guidance values (HBGV).
- Paralytic Shellfish Poisoning due to ingestion of contaminated mussels: a case report in Caparica (Portugal)Publication . Ribeiro, I.; Pelerito, A.; Cordeiro, R.; Vale, P.; Núncio, M.S.; Lopes de Carvalho, I.In Portugal, the potent paralytic shellfish toxins (PSTs) have appeared irregularly since the onset of a national monitoring program for marine biotoxins in 1986. In years where high contamination levels were attained in bivalves, sporadic cases of human poisonings have been recorded, as in 1994 and 2007. The reappearance of high contamination levels led to the appearance of new cases during the autumn of 2018. This study reports the case of two patients that ingested mussels from the Portuguese southwest coast and required hospitalization due to the severity of symptoms. Details of toxin ingestion, symptomatology and toxin metabolization in the fluids are described. The diagnosis was confirmed by ELISA in plasma and urine samples. In mussel samples, the toxin profile obtained by HPLC-FLD displayed a wide diversity of toxins, typical of Gymnodinum catenatum ingestion. However, in the urine samples toxin profile was reduced to B1 and dcSTX. Abundant compounds in mussels having an O-sulfate at C11, such as C1+2 and dcGTX2+3, were absent in urine. In plasma, PSTs were not detected by HPLC-FLD. Calculated toxin ingestion, resulting from consumption of an estimated 200-gram portion, was in the range of 104-120 µg STX eq./kg b.w. This study alerts physicians to be aware of this human syndrome with only sporadic occurrence in Portugal.
- The importance of wildlife health on zoonotic bacteria transmission: interactions between Borrelia burgdorferi s.l. and its avian hostsPublication . Norte, A.C.; Heylen, D.; Araújo, P.M.; Pascoal da Silva, L.; Sprong, H.; Krawczyk, A.; Costantini, D.; Eens, M.; Núncio, M.S.; Ramos, J.A.; Lopes de Carvalho, I.Borrelia burgdorferi sensu lato (s.l.) is a tick-borne zoonotic agent maintained in enzootic cycles in nature by vertebrate reservoir hosts, including mammals, lizards and birds. To understand the eco-epidemiology of Lyme borreliosis it is necessary to evaluate the relationships between Borrelia genospecies and vertebrate reservoir hosts. We surveyed Borrelia infection prevalence in avian hosts and using wild birds as models, we assessed the physiological impact of infection in reservoir hosts and how exposure to stress could affect hosts’ infectivity to vector ticks. This helps to understand how these host-parasite interactions may affect tick-borne zoonotic agents’ circulation and transmission, and, ultimately, disease risk. Thrushes (Turdus spp.) were the most important birds in the enzootic cycle of Borrelia. The diversity of Borrelia genospecies detected in ticks feeding on birds was high, and the most common genospecies was B. garinii, a pathogenic genospecies. The ubiquitous blackbird Turdus merula successfully transmitted B. turdi, B. valaisiana and B. burgdorferi s.s. to vector ticks in laboratory conditions. There was no evidence that exposure to stress increased infectivity of wild avian hosts to vector ticks in an experiment performed in captivity. However, oxidative balance (protein carbonyls and glutathione peroxidase levels) of naïve blackbirds was affected by experimental infection with Borrelia, suggesting that these bacteria may inflict non-negligible physiological harm on its natural reservoir hosts with potential impact on transmission success.
- Environmental exposures in young adults with declining kidney function in a population at risk of Mesoamerican nephropathyPublication . Smpokou, Evangelia-Theano; González-Quiroz, Marvin; Martins, Carla; Alvito, Paula; Le Blond, Jennifer; Glaser, Jason; Aragón, Aurora; Wesseling, Catharina; Nitsch, Dorothea; Pearce, Neil; Norman, Jill; Lindh, Christian; Morton, Jackie; Caplin, BenObjectives: There is an epidemic of Mesoamerican nephropathy (MeN) in Central America, where sugarcane production is prominent. Numerous causes are proposed, but to date limited evidence supports any one hypothesis. A nested case-control study using biosamples from a rural, community-based follow-up study of 350 young adults from Northwest Nicaragua at risk of MeN was conducted with the aim of characterising the associations between urinary concentrations of metals, pesticides and mycotoxins from samples collected in the first 6 months and decline in kidney function over 2 years. Methods: Urine samples collected at baseline (pre-sugarcane harvest) and the first 6 month follow-up (post-sugarcane harvest) visit were tested. Twelve metals and metalloids (aluminium, total arsenic, cadmium, chromium, cobalt, copper, lead, manganese, mercury, selenium, silicon and strontium) were analysed by inductively coupled plasma-mass spectrometry. Twelve pesticides or their metabolites (2,4-dichlorophenoxyacetic acid, 3-phenoxybenzoic acid, 4-fluoro-3-phenoxybenzoic acid, chloro-3,3,3-trifluoro-1-propen-1-yl-2,2-dimethylcyclopropanecarboxylic acid, cis/trans 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid, ethylenethiourea, glyphosate, 4-chloro-2-methylphenoxy acetic acid, 3-hydroxy-pyrimetanil, 5-hydroxytiabendazole, hydroxy-tebuconazole and 3,5,6-trichloro-2-pyridinol) and two mycotoxins (ochratoxin A (OTA) and citrinin (CIT)) were analysed by liquid chromatography coupled-mass spectrometry. Differences in the creatinine-corrected urinary concentrations of the measured exposures between outcome groups (participants with stable vs declining kidney function) were examined. Results: Elevated levels of aluminium and total arsenic as well as metabolites of several pesticides were detected across the population. No differences were identified between the declining and stable groups in the levels of metals or pesticides tested. OTA and CIT were below the limit of detection. Conclusions: The tested metals, metalloids, pesticides and mycotoxins were not associated with loss of kidney function in participants at-risk of MeN.
- Building capacity in risk-benefit assessment of foods: lessons learned from the RB4EU ProjectPublication . Boué, Géraldine; Assunção, Ricardo; Alvito, Paula; Brazão, R.; Carmona, Paulo; Carvalho, Catarina; Correia, D.; Fernandes, Paulo; Jakobsen, Lea; Lopes, Carla; Martins, Carla; Membré, Jeanne-Marie; Monteiro, Sarogini; Nabais, Pedro; Thomsen, Sofie; Torres, Duarte; Pires, SaraRisk-Benefit Assessment (RBA) of food, food ingredients and diets, has recently emerged to address multidisciplinary public health issues. RBA aims to assess in a global perspective potential risks and benefits related to microbiology, toxicology and nutrition; in order to evaluate different options and to support decision-making process. At this time, significant methodological progress have been made but only few research groups have experience in RBA. To promote knowledge transfer, the RiskBenefit4EU project was funded by the European Food Safety Authority (EFSA). The objective of the presentation will be to introduce the strategy developed to capacitate a new team in RBA and to give an overview on lessons learned from this experience. The new team was comprised of experts in risk assessment in toxicology, microbiology or nutrition, epidemiology, dietary assessment or data analysis to answer to a specific multidisciplinary public health issue on cereal-based foods consumed by young children considering breakfast and infant cereals. Activities of the capacity building experience were designed by experienced researchers in RBA to transfer a harmonized methodology. Two weeks of face-to-face training were organized, one on theoretical concepts used in RBA and one on their application to the cereal case study. This experience has highlighted the necessity to build a common language within the team by harmonizing important concepts including hazard, health effect, adverse health effect, beneficial health effect, risk, benefit, health and health impact. It was also important that all participant learn basis of all area of expertise used in RBA. A harmonized RBA stepwise approach was introduced with key steps illustrated with examples of previous RBA performed. Finally, the RBA case study was initiated to design a shared protocol. The learning by doing process experienced under the RB4EU project enabled to create the first training in RBA. The strategy developed, with materials and method used, can now be re-used to capacitate other new teams in RBA and can be considered as a robust basis to build on.
- Risk-benefit assessment of cereal-based foods consumed by children - a case study under RB4EU projectPublication . Assunção, Ricardo; Boué, Géraldine; Alvito, Paula; Brazão, R.; Carmona, Paulo; Carvalho, Catarina; Correia, D.; Fernandes, Paulo; Jakobsen, Lea; Lopes, Carla; Martins, Carla; Membré, Jeanne-Marie; Monteiro, Sarogini; Nabais, Pedro; Thomsen, Sofie; Torres, Duarte; Pires, SaraFoodstuffs, as cereal-based products, may present both potential risks and benefits to consumers. Cereal-based foods including breakfast and infant cereals, represent important components of human diets and are also among the first solid foods that young children usually eat. From the risk components, cereals are one of the most frequent foodstuffs contaminated by mycotoxins. Aflatoxins, a frequent mycotoxin found in cereals, are undoubtedly the most toxic and are associated to genotoxic, carcinogenic and immunosuppressive toxic effects. Besides chemical hazards, cereal-based foods also potentially contain microbiological hazards, as e.g. Bacillus cereus. Despite the fact that organisms cannot easily grow in low moisture foods as e.g. breakfast and infant cereals, B. cereus can persist for long periods of time and can cause illness due to possible subsequent temperature abuse that allows the organism to grow. Cereal-based products are also a source of several nutrients, including sodium, fibre and free sugars. High sodium intake is linked to increased blood pressure and also represents a risk factor of cardiovascular diseases. Regarding free sugars, WHO strongly recommends a reduced intake, up to 10% of total energy. Dietary fibre intake contributes to significant immediate and future health benefits, as e.g. promotion of normal gastrointestinal function, prevention of childhood obesity and risk reduction for future chronic diseases. The present case study, developed under RiskBenefit4EU project and funded by EFSA, aimed to assess the risks and the benefits associated to the consumption of cereal-based products by the Portuguese young children. The risks posed by breakfast and infant cereals, due to aflatoxins, B. cereus, sodium and free sugars, were evaluated against the benefits of the intake of fibre. Obtained results showed that moving from the current consumption to the considered alternative scenarios could result in a gain of healthy-life years.