Loading...
7 results
Search Results
Now showing 1 - 7 of 7
- Evaluation of the cytotoxicity and genotoxicity of ingested titanium dioxide nanomaterials in intestinal cellsPublication . Gramacho, Ana Catarina; Martins, Carla; Assunção, Ricardo; Gonçalves, Lídia; Simão Bettencourt, Ana; Paula, Alvito; Silva, Maria João; Louro, HenriquetaMany products already available, namely in agriculture and food, contain nanomaterials (NMs) and thus human ingestion of these compounds is probable through consumer products or food chain. Although NMs have been extensively investigated in recent years, the studies have generated contradictory results, possibly due to differences in the physicochemical properties of the NMs studied and to other variables in the tested systems. Furthermore, the NMs properties have been recognized as being context-dependent, i.e. can be affected by the surrounding matrix. These secondary features may be potentially more relevant for determining the toxicological outcome. In particular, processes like digestion may modify the NMs characteristics leading to unexpected toxicity in intestine cells. This work aimed to investigate the nano-bio interactions of titanium dioxide NMs (from Joint Research Centre, Ispra) in the context of intestinal tract and digestion processes, to better understand key events that may be linked to an adverse outcome pathway (AOP). In vitro for digestion was simulated and the NMs secondary properties in the intestinal cell moiety were characterized after this process. The cytotoxic and genotoxic effects of digested NMs were determined after the in vitro exposure of human intestinal cells (Caco-2). In addition, the FPG-comet assay was used to analyze oxidative DNA lesions. The digestion products without the NM showed cytotoxic effects above the concentration of 10% in cell culture medium, leading to the need to reduce its concentration below this level. Therefore, initial dose-range studies set a working range of NM concentrations of 0.14 up to 14 µg/ml (0.5-4.5 % of digestion product), which relates also with the predicted levels of exposure of human intestinal cells in real life conditions. Under these conditions, the preliminary results suggest that the tested titanium dioxide NMs do not yield cytotoxic or genotoxic effects upon 24h of exposure of Caco-2 cells, directly after the digestion process. Future studies will investigate the subcellular localization of NMs, integrity of cell junctions, activation of stress signaling pathways and secretion of inflammatory cytokines, to allow an integrated approach to potential adverse effects of the NMs. By elucidating key events elicited by NMs, linking exposure to adverse outcomes, it is expected to contribute to the safety evaluation of NMs within an AOP landscape.
- Organic dust exposure in veterinary clinics: a case study of a small-animal practice in PortugalPublication . Viegas, Carla; Monteiro, Ana; Ribeiro, Edna; Caetano, Liliana Aranha; Carolino, Elisabete; Assunção, Ricardo; Viegas, SusanaLiterature about occupational health in small-animal veterinary practices is scarce, but most of it has recognised a number of risks to be considered, including organic dust exposure. The aim of this pilot study was to assess organic dust, bacterial, and fungal contamination in the indoor environment of a typical Portuguese veterinary clinic but also to screen for azoleresistant fungi. To complement these findings we also analysed workers' nasal exudates for resistant bacteriota. Particles measurements included mass concentrations (PMC) of five particle sizes (PM0.5, PM1, PM2.5, PM5, PM10) and their counts (PNC). Indoor air samples were obtained from six locations as well as before and during cat dental cleaning and cultured on four media for bacterial and fungal assessment. An outdoor sample was also collected for reference Surface samples were taken from the same indoor locations using swabs and we also use electrostatic dust cloths as passive methods. PM10 showed the highest concentrations across the locations. Indoor air fungal loads ranged from 88 to 504 CFU m-3. The azole-resistant Aspergillus section Nigri was identified in one sample. Indoor air bacterial loads ranged from 84 to 328 CFU m-3. Nasopharyngeal findings in the 14 veterinary clinic workers showed a remarkably low prevalence of Staphylococcus aureus (7.1 %). Our results point to contamination with organic dusts above the WHO limits and to the need for better ventilation. Future studies should combine the same sampling protocol (active and passive methods) with molecular tools to obtain more accurate risk characterisation. In terms of prevention, animals should be caged in rooms separate from where procedures take place, and worker protection should be observed at all times.
- Human biomonitoring in health risk assessment in Europe: current practices and recommendations for the futurePublication . Louro, Henriqueta; Heinälä, Milla; Bessems, Jos; Buekers, Jurgen; Vermeire, Theo; Woutersen, Marjolijn; van Engelen, Jacqueline; Borges, Teresa; Rousselle, Christophe; Ougier, Eva; Alvito, Paula; Martins, Carla; Assunção, Ricardo; Silva, Maria João; Pronk, Anjoeka; Schaddelee-Scholten, Bernice; Del Carmen Gonzalez, Maria; de Alba, Mercedes; Castaño, Argelia; Viegas, Susana; Humar-Juric, Tatjana; Kononenko, Lijana; Lampen, Alfonso; Vinggaard, Anne Marie; Schoeters, Greet; Kolossa-Gehring, Marike; Santonen, TiinaHuman biomonitoring (HBM) is an important tool to survey the internal exposure of humans which represents the real life chemical body burden to chemicals and/or their metabolites. It results from total exposure to chemical substances from different sources and via different routes. These substances may be regulated under different legislative frameworks on chemicals (e.g., environmental, occupational, food safety etc). In occupational health, HBM has long traditions to control the exposures at workplaces. By providing accurate data on internal exposure, HBM data can improve human health risk assessment (RA) for both the general population and workers. Although the past few years have shown good examples on the use of HBM in the RA of chemicals, there is still quite some work to be done to improve its use in a regulatory RA. Under the scope of the European Human Biomonitoring Initiative (project HBM4EU, 2017-2021), the current study reviews the state-of-the-art of HBM use in chemicals RA with a special focus in Europe, and attempts to identify hurdles and challenges faced by regulators. To gather information on the use of HBM, including the availability of guidance on how to use it in RA, the RA schemes applied by different European or international organizations were analysed. Examples of such use were identified for a few selected groups of chemicals of concern for human health. In addition, we present the results of a survey, aimed at collecting information from national regulatory risk assessors on their day-to-day RA practices, the use of HBM data, and the obstacles and challenges related to their use. The results evidenced and explained some of the current obstacles of using HBM data in RA. These included the lack of HBM guidance values or biomonitoring equivalents (BEs), limited toxicokinetic information to support the interpretation of HBM data and, in the occupational health and safety (OSH) field, the lack of legal enforcement. Therefore, to support the integration of HBM in regulatory RA, we recommend, on one hand, the elaboration of a EU level guidance on the use of HBM in RA and, on the other hand, the continuation of research efforts to integrate HBM with new RA approaches using in vitro/in silico data and Adverse Outcome Pathways (AOPs).
- Years of life lost associated with COVID-19 deaths in Portugal: two years of pandemicPublication . Martins, Carla; Santos, João Almeida; Assunção, RicardoBackground: The impact of the COVID-19 pandemic on the Portuguese population is still underexplored. Therefore, the characteriza tion of years of life lost (YLL) due to this epidemic may provide relevant data for establishing effective strategies in future epidemics. The aim of this study was to calculate YLL associated with COVID-19 deaths in Portugal between 2020 and 2022. Methods: This was an observational, cross-sectional study. Data on the average resident population and life expectancy at birth by age group and sex were obtained from Statistics Portugal (INE) and GBD 2019 standard life-table, respectively. Data on COVID-19 deaths were extracted from the Directorate-General of Health’s (DGS) reports. YLL was calculated as the number of COVID-19 deaths multiplied by standard life expectancy at the age of death, globally, by sex and age group. YLL was calculated by 100,000 population and age-standardized. Results: Between 2020 and 2022, 3413013 cases of COVID-19 were reported in Portugal, of which 21342 (0.6%) eventually died of the disease. The number of deaths by sex was similar globally or by age group. Globally, the YLLs estimated for COVID-19 in Portugal were 309383,8. YLLs were higher for males than for females for most age groups except of age groups 10-19 yrs (76.56 vs 153.11) and > 80 yrs (58710.88 vs 68491.44). YLLs age-standardized also showed a steady increase as we progressed in the age group [from 3.25 (0-9 yrs) to 885.54 (>80 yrs)], in which from the 50-59 yrs age group onwards we observed a steeper slope of increase in YLLs. Conclusions: COVID-19 has had a major impact on mortality rates in Portugal, with this impact being greater in the older population, especially in people aged over 70 years. Also, males presented higher YLLs than females, with this difference increasing substantially as age increases. These insights can be useful in terms of public health as the disease progresses to an endemic phase.
- HBM4EU-MOM: Prenatal methylmercury-exposure control in five countries through suitable dietary advice for pregnancy – Study design and characteristics of participantsPublication . Katsonouri, Andromachi; Gabriel, Catherine; Esteban López, Marta; Namorado, Sónia; Halldorsson, Thorhallur; Snoj Tratnik, Janja; Rodriguez Martin, Laura; Karakoltzidis, Achilleas; Chatzimpaloglou, Anthoula; Giannadaki, Despina; Anastasi, Elena; Thoma, Anthi; Domínguez-Morueco, Noelia; Cañas, Ana; Jacobsen, Eva; Assunção, Ricardo; Peres, Maria; Santiago, Susana; Nunes, Carla; Pedraza-Diaz, Susana; Iavicoli, Ivo; Leso, Veruscka; Lacasaña, Marina; González-Alzaga, Beatriz; Horvat, Milena; Sepai, Ovnair; Castano, Argelia; Kolossa-Gehring, Marike; Karakitsios, Spyros; Sarigiannis, DimosthenisBackground: Seafood is a major source of vital nutrients for optimal fetal growth, but at the same time is the main source of exposure to methylmercury (MeHg), an established neurodevelopmental toxicant. Pregnant women must be provided with dietary advice so as to include safely fish in their diet for nutrition and mercury control. The aim of this work is to present the design of a multicentre randomized control trial (RCT), which combines human biomonitoring (HBM) with dietary interventions using seafood consumption advice to pregnant women for MeHg control, and to collect information about other possible sources of exposure to mercury. It also presents the materials developed for the implementation of the study and the characteristics of the study participants, which were self-reported in the first trimester of pregnancy. Methods: The "HBM4EU-MOM" RCT was performed in the frame of the European Human Biomonitoring Initiative (HBM4EU) in five coastal, high fish-consuming European countries (Cyprus, Greece, Spain, Portugal and Iceland). According to the study design, pregnant women (≥120/country, ≤20 weeks gestational age) provided a hair sample for total mercury assessment (THg) and personal information relevant to the study (e.g., lifestyle, pregnancy status, diet before and during the pregnancy, information on seafood and factors related to possible non-dietary exposures to mercury) during the first trimester of pregnancy. After sampling, participants were randomly assigned to "control" (habitual practices) or "intervention" (received the harmonized HBM4EU-MOM dietary advice for fish consumption during the pregnancy and were encouraged to follow it). Around child delivery, participants provided a second hair sample and completed another tailored questionnaire. Results: A total of 654 women aged 18-45 years were recruited in 2021 in the five countries, primarily through their health-care providers. The pre-pregnancy BMI of the participants ranged from underweight to obese, but was on average within the healthy range. For 73% of the women, the pregnancy was planned. 26% of the women were active smokers before the pregnancy and 8% continued to smoke during the pregnancy, while 33% were passive smokers before pregnancy and 23% remained passively exposed during the pregnancy. 53% of the women self-reported making dietary changes for their pregnancy, with 74% of these women reporting making the changes upon learning of their pregnancy. Of the 43% who did not change their diet for the pregnancy, 74% reported that their diet was already balanced, 6% found it difficult to make changes and 2% were unsure of what changes to make. Seafood consumption did not change significantly before and during the first trimester of pregnancy (overall average ∼8 times per month), with the highest frequency reported in Portugal (≥15 times per month), followed by Spain (≥7 times per month). During the first-trimester of pregnancy, 89% of the Portuguese women, 85% of the Spanish women and <50% of Greek, Cypriot and Icelandic women reported that they had consumed big oily fish. Relevant to non-dietary exposure sources, most participants (>90%) were unaware of safe procedures for handling spillage from broken thermometers and energy-saving lamps, though >22% experienced such an incident (>1 year ago). 26% of the women had dental amalgams. ∼1% had amalgams placed and ∼2% had amalgams removed during peri-pregnancy. 28% had their hair dyed in the past 3 months and 40% had body tattoos. 8% engaged with gardening involving fertilizers/pesticides and 19% with hobbies involving paints/pigments/dyes. Conclusions: The study design materials were fit for the purposes of harmonization and quality-assurance. The harmonized information collected from pregnant women suggests that it is important to raise the awareness of women of reproductive age and pregnant women about how to safely include fish in their diet and to empower them to make proper decisions for nutrition and control of MeHg, as well as other chemical exposures.
- Mycotoxins feed contamination in a dairy farm - potential implications for milk contamination and workers' exposure in a One Health approachPublication . Viegas, Susana; Assunção, Ricardo; Twarużek, Magdalena; Kosicki, Robert; Grajewski, Jan; Viegas, CarlaDairy farming feed can be contaminated with mycotoxins, affecting animals' health and milk quality. Dairy farming is also prone to occupational exposure to mycotoxins, and feed is recognized as a source of contamination in the workplace. An exploratory study was developed in a dairy farm located in Portugal intending to assess the mycotoxins present in the feed.
- earlyMYCO: A Pilot Mother-Child Cohort Study to Assess Early-Life Exposure to Mycotoxins - Challenges and Lessons LearnedPublication . Martins, Carla; Assunção, Ricardo; Costa, Ana; Serrano, Débora; Visintin, Lia; De Boevre, Marthe; Lachat, Carl; Vidal, Arnau; De Saeger, Sarah; Namorado, Sónia; Vidigal, Cristina; Almeida, Elisabete; Alvito, Paula; Nunes, CarlaEarly-life exposure occurs during gestation through transfer to the fetus and later, during lactation. Recent monitoring data revealed that the Portuguese population is exposed to mycotoxins, including young children. This study aimed to develop a pilot study to assess the early-life exposure to mycotoxins through a mother-child cohort, and to identify the associated challenges. Participants were recruited during pregnancy (1st trimester) and followed-up in three moments of observation: 2nd trimester of pregnancy (mother), and 1st and 6th month of the child's life (mother and child), with the collection of biological samples and sociodemographic and food consumption data. The earlyMYCO pilot study enrolled 19 mother-child pairs. The analysis of biological samples from participants revealed the presence of 4 out of 15 and 5 out of 18 mycotoxins' biomarkers of exposure in urine and breast milk samples, respectively. The main aspects identified as contributors for the successful development of the cohort were the multidisciplinary and dedicated team members in healthcare units, reduced burden of participation, and the availability of healthcare units for the implementation of the fieldwork. Challenges faced, lessons learned, and suggestions were discussed as a contribution for the development of further studies in this area.