Browsing by Issue Date, starting with "2019-11-18"
Now showing 1 - 3 of 3
Results Per Page
Sort Options
- Occupational exposure to hexavalent chromium: biomarkers of genotoxicity in human peripheral bloodPublication . Afonso, Catarina Maia; Louro, Henriqueta; Silva, Maria JoãoThe hexavalent Chromium [Cr(VI)] is a human carcinogen, which is still authorized for use in several industrial settings because it has been difficult to replace. This was the reasoning to select it as a priority chemical by the European Human Biomonitoring Initiative (HBM4EU, https://www.hbm4eu.eu/), which aims to bridge chemicals human exposure to their possible impact on health. For that purpose, not only exposure was evaluated, but also early effect biomarkers were done to reflect potential health outcomes in several countries across Europe. In Portugal, the study was developed in one aircraft maintenance company since the substitution of Cr(VI) is not expected in the near future. Following the company agreement and the volunteers informed consent, an individual questionnaire was filled in order to obtain personal information, as well as lifestyle habits and occupational issues. Personal air samples were collected in order to assess occupational exposure to Cr(VI) soluble and insoluble compounds. Sampling for effect biomarkers analyses involved blood samples from 50 workers and 26 healthy individuals (controls). Biomarkers of effect involving the analysis of chromosome alterations (micronucleus assay) and DNA damage (comet assay) were studied; the results were statistically compared. Cr(VI)-exposed workers display a significantly higher frequency of micronucleated binucleated cells (p < 0.001) and an increased level of DNA breaks (comet assay) (p < 0.001) when compared with the non-exposed group. Only in the workplaces dedicated to painting exterior surfaces the values (0.4 mg/m3) were higher than the Occupational Exposure Limit (OEL of 0.010 mg/m3) currently proposed by the Directive (EU) 2019/130, 16/01/2019.The present results suggest a potential health risk for this group of workers given that an association between an increased micronucleus frequency and cancer risk has been shown. Also, these findings should promote the investment in new risk management measures and the effective application of the ones already in place, such as adequate local ventilation and a frequent use of protective equipment.
- Exposure assessment in one central hospital: A multi-approach protocol to achieve an accurate risk characterizationPublication . Viegas, Carla; Almeida, Beatriz; Monteiro, Ana; Paciência, Inês; Rufo, João; Aguiar, Lívia; Lage, Bruna; Diogo Gonçalves, Lídia Maria; Caetano, Liliana Aranha; Carolino, Elisabete; Gomes, Anita Quintal; Twarużek, Magdalena; Kosicki, Robert; Grajewski, Jan; Teixeira, João Paulo; Viegas, Susana; Pereira, CristianaThe bioburden in a Hospital building originates not only from patients, visitors and staff, but is also disseminated by several indoor hospital characteristics and outdoor environmental sources. This study intends to assess the exposure to bioburden in one central Hospital with a multi-approach protocol using active and passive sampling methods. The microbial contamination was also characterized through molecular tools for toxigenic species, antifungal resistance and mycotoxins and endotoxins profile. Two cytotoxicity assays (MTT and resazurin) were conducted with two cell lines (Calu-3 and THP-1), and in vitro pro-inflammatory potential was assessed in THP-1 cell line. Out of the 15 sampling locations 33.3% did not comply with Portuguese legislation regarding bacterial contamination, whereas concerning fungal contamination 60% presented I/O > 1. Toxigenic fungal species were observed in 27% of the sampled rooms (4 out of 15) and qPCR analysis successfully amplified DNA from the Aspergillus sections Flavi and Fumigati, although mycotoxins were not detected. Growth of distinct fungal species was observed on Sabouraud dextrose agar with triazole drugs, such as Aspergillus section Versicolores on 1 mg/L VORI. The highest concentrations of endotoxins were found in settled dust samples and ranged from 5.72 to 23.0 EU.mg-1. While a considerable cytotoxic effect (cell viability < 30%) was observed in one HVAC filter sample with Calu-3 cell line, it was not observed with THP-1 cell line. In air samples a medium cytotoxic effect (61-68% cell viability) was observed in 3 out of 15 samples. The cytokine responses produced a more potent average cell response (46.8 ± 12.3 ρg/mL IL-1β; 90.8 ± 58.5 ρg/mL TNF-α) on passive samples than air samples (25.5 ± 5.2 ρg/mL IL-1β and of 19.4 ± 5.2 ρg/mL TNF-α). A multi-approach regarding parameters to assess, sampling and analysis methods should be followed to characterize the biorburden in the Hospital indoor environment. This study supports the importance of considering exposure to complex mixtures in indoor environments.
- Lessons from Ciência Viva: how teaching human genetics to XXIst century students must go beyond the classroomPublication . Quint, Meghan; Amaral, OlgaScience education plays a vital role for decision making in an informed society as well as for informed choices in a pre-university setting. In 1997, Portugal launched a national Science program known as Ciência Viva, including the Summer Internship Program (SIP) which, along with other initiatives such as the Science Centers and science annual events, aiming to bring science awareness closer to the population. The free SIP provides short term internships to Portuguese secondary school students throughout the country. We advocate for public and private research institutions across Europe to maintain involvement in, or create, similar scientific development opportunities that are free of cost to students. We recognize that initiatives like these require the proper infrastructure and interest amongst researchers. However, we stress the long-term benefit to the scientific community as well executed programs help draw interest towards Science fields