DSA - Posters/abstracts em congressos internacionais
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- Toxic cyanobacteria blooms in Portuguese freshwaters – a summarized overviewPublication . Paulino, Sérgio; Faria, Natália; Valério, Elisabete; Pereira, Paulo; Tavares, AntónioToxic cyanobacteria are common in Portuguese freshwaters and are a cause of concern, given that exposure to subacute levels of cyanobacterial toxins through drinking and recreational water might have deleterious effects on human health. Since 1996 several laboratories have been involved in the screening of cyanotoxins in different freshwater bodies, some on regularly basis and others more sporadically. Here we summarized the main data obtained by our laboratory during the last years, in order to give a simplified overview of the quality and diversity of our freshwater resources in terms of cyanobacteria occurrence.
- Coleção de culturas de algas Estela Sousa e SilvaPublication . Menezes, Carina; Churro, Catarina; Paulino, Sérgio; Sam-Bento, Filomena; Alverca, Elsa; Dias, Elsa; Pereira, PauloA coleção de culturas de algas Estela Sousa e Silva (ESSACC) foi criada em 1956 e reside atualmente no Laboratório de Biologia e Ecotoxicologia no Instituto Nacional de Saúde Dr. Ricardo Jorge. A ESSACC foi implementada em resposta à necessidade de um repositório de material biológico para investigação na área do fitoplâncton. Este importante recurso biológico contém culturas monoclonais de algas eucarióticas e cianobactérias provenientes de águas costeiras e albufeiras portuguesas. Atualmente, a coleção mantém acima de 176 isolados vivos, dos quais 151 são cianobactérias de água doce e 25 são dinoflagelados marinhos. Adicionalmente são também mantidos alguns isolados pertencentes a outros grupos de fitoflagelados. Esta coleção permitiu até agora a identificação e caracterização de espécies assim como a produção e purificação de toxinas para aplicação em estudos toxicológicos entre outras diversas áreas de investigação. Deste modo, a ESSACC constitui uma ferramenta importante no fornecimento de culturas de algas a investigadores na área do fitoplâncton, particularmente no estudo de espécies nocivas.
- Bisphenol a releasing by plastic container with gas chromatography tandem mass spectometryPublication . Rocha, S.; Domingues, V.F.; Mansilha, C.; Pinho, C.; Gameiro, P.; Delerue-Matos, C.
- Emerging water contaminantsPublication . Mansilha, C.; Melo, A.; Ferreira, I.; Domingues, V.; Pinho, C.; Rocha, S.; Gameiro, P.
- Formation of Emerging Disinfection Byproducts in Water and Evaluation of Potential Genotoxic Effects: the Case of Chlorinated Polycyclic Aromatic HydrocarbonsPublication . Rebola, M.; Pinto, M.; Louro, H.; Antunes, A.M.M.; José, S.S.; Rocha, M.R.; Silva, M.J.; Cardoso, A. S.Disinfection byproducts (DBPs) are formed when disinfectants used in water treatment plants (WTPs) react with natural (or anthropogenic) organic matter present in the source water. Many studies have addressed health risks posed by a life-time exposure to DBPs through chlorinated drinking water or through dermal or inhalation exposure routes. Experimental studies have revealed genotoxic and carcinogenic effects of some DBPs and epidemiological studies evidenced potential associations between chlorinated drinking water and bladder or colorectal cancer. In addition, a possible link between chlorinated drinking water and reproductive/developmental effects has been hypothesized. Many DBPs have been identified in treated water, which justifies the growing concern about the potential health effects of emerging unregulated DBPs, some of which appear to be more genotoxic, in some assays, than the regulated DBPs. Polycyclic aromatic hydrocarbons (PAHs) are among the most persistent contaminants detected in environmental samples such as river sediments and tap water. Water chlorination can lead to the formation of chlorinated derivatives of PAHs (Cl-PAHs) and the few available toxicological studies have shown that Cl-PAHs possess greater mutagenicity than the corresponding parent PAHs. The present study had two main objectives: 1) identification of the major chlorinated derivatives of benzo[a]pyrene (BaP) and fluoranthene (Fluo) formed as chlorination by-products and 2) evaluation of their potential hazard to humans, through the characterization of their potential genotoxic effects in a human cell line. To synthesize chlorinated standards of PAHs, a newly two phase (water/n-hexane) method was developed for BaP and Fluo. 6-Cl-BaP was obtained as the major chlorination product of BaP, and 3-Cl-Fluo and 1,3-Cl2-Fluo of Fluo. The formation of these BaP and Fluo chlorinated derivatives was also observed under WTPs chlorination conditions after at 0.5 until 24 h of exposure. The effects of equimolar concentrations of 6-Cl-BaP vs. BaP and of 3-Cl-Fluo/1,3-Cl2-Fluo vs. Fluo on cell viability and DNA integrity were assessed by the neutral red uptake (NR) and the comet assay, respectively. Exposure of HepG2 cells to a dose-range of 6-Cl-BaP and BaP showed that both compounds are cytotoxic above 50 μM and that, at the equimolar doses of 100 and 125 μM, 6-Cl-BaP is able to induce a significantly higher level of DNA damage than BaP. On the other hand, no changes of cell viability were observed after exposure to several concentrations of Fluo and its derivatives. Likewise, none of the compounds was able to significantly induce DNA damage. In conclusion, the present data confirmed that chlorinated derivatives of BaP and Fluo are formed during WTPs chlorination procedures and allowed the identification of their major chlorinated derivatives that should be further analysed in drinking water. On the other hand, the results from the comet assay evidenced a higher DNA damaging effect of Cl-BaP comparatively to its parent compound, suggestive of a more potent genotoxic effect. In spite of the negative results found for Fluo and its chorinated products, further genotoxicity studies are still needed to allow a definite conclusion. Although health risks of DBPs are small compared to health risks of waterborne diseases, the identification of hazardous Cl-PAHs in water emphasizes the need of development of new and safer water disinfection methods.
- Air Quality in a children Day Care Centres - Pilot StudyPublication . Cano, M.; Aguiar, F.; Almeida, G.; Proença, C.The negative impact of a poor indoor air quality in children’s health is well recognized and the establishment of a relation between air quality, ventilation and children’s health is crucial to correct the actual situation. Levels of carbon dioxide usually exceed recommended values and are often associated with the raise of many other indoor pollutants accumulated in consequence of poor ventilation rates. This paper describes field measurements of chemical and biological indoor contaminants in order to investigate indoor air quality in a children day care center (CDCC). Objective The aim of this pilot study was to point out the need for indoor air quality investigations in CDCC in order to control ventilation rates and prevent children respiratory diseases. Material and Methods The monitoring tasks were carried out in a CDCC in Lisbon with the evaluation of suspended particulate matter, carbon dioxide, carbon monoxide, total volatile organic compounds (TVOC’s), bacteria and fungi. Relevant measurements of chemical and biological parameters were also conducted outdoors. The studied CDCC had mixed ventilation with extraction in toilets and openable windows. Carbon monoxide, carbon dioxide and TVOC’s were monitored using a Photoacoustic Multigas Monitor Type 1312, INNOVA, Air Tech Instruments. Particulate matter was collected by active sampling into PVC filters using pumps operating at 2 L/min airflow, followed by gravimetric analysis. Samples of viable microorganisms were collected using the MAS-100 sampler with Malt Extract Agar (MEA) plates supplemented with chloranphenicol, Trypticase Soy Agar (TSA) and MacConkey agar as collecting media for fungi, total bacteria and gram-negative bacteria respectively. Field campaign was conducted in March 2008, during routine school activities (10:00-17:00). Results TVOC’s concentrations exceed recommended limits in one of the ten studied rooms, being also one of the rooms with CO2 concentration above the recommended value (2200 mg/m3). CO concentrations ranged from 0,064 mg/m3 to 0,361 mg/m3 never exceeding 12,5 mg/m3. The mean CO2 concentration indoors exceeds 1800 mg/m3 in 7 of the 10 studied rooms, with a maximum concentration of 3750 mg/m3, a minimum of 1630 mg/m3 and an outdoor level of 773 mg/m3. The results obtained show a relation between CO2 and bacterial concentrations, being also observed a predominance of gram-positive bacteria. Fungal spore concentrations ranged from 116 to 476 ufc/m3 and the outdoor level (582 ufc/m3) was never exceeded. The maximum total suspended particulate matter concentration obtained was 0,162 mg/m3 with an outdoor level of 0,062 mg/m3, the minimum level was obtained in the nursery (0,051 mg/m3). Conclusion This pilot study provides evidence that ventilation in the monitored CDCC is clearly insufficient to maintain an acceptable indoor air quality. Being the human occupancy the major source of CO2 and bacteria, it is possible to predict the accumulation of other infectious agents, such as human origin viruses and also of chemical contaminants from indoor sources, as a consequence of poor ventilation. These results are in accordance with previous studies that report an increased risk of infectious diseases of children attending day care centers compared with those cared for at home. Further research is needed with an enlarged number of CDCC in order to develop guidelines to create healthy environments for children.
- Tobacco Smoke Occupational Exposure: Biomarkers of Biological DamagePublication . Simões, Tânia; Milic, Vukosava D.; Pacheco, S.A.; Aguiar, Fátima; Gomes, Filomena; Louro, Henriqueta; Vital, Nádia; Antunes, Susana; Charro, Nuno; Bruno, Alexandre; Vaz, Fátima; Lopes, C.; Marçal, N.; Fragoso, E.; Proença, C.; Sekera, M.; Hagenfeld, Manuela; Silva, Maria João; Almeida, A.B.; Penque, Deborah; Ruivo, P.High concentration of toxic substances emanated from tobacco smoke in entertainment places such as restaurants, bars and nightclubs may compromise indoor air quality (IAQ) generating environments of likelihood health risk. Their employees, particularly those exposed to second-hand smoke, are at increased risk for developing chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD), asthma and lung cancer. Objectives In this work, we aimed at evaluating relationships between occupational ETS exposure, biological damage (DNA or proteome alterations) and putative respiratory dysfunctions. Materials and Methods A group of restaurants located in Lisbon has been studied, in which fine particles (smaller than 2.5µm; PM2.5), indicative of environmental tobacco smoke (ETS) contamination, were measured. After informed consent, workers were evaluated for acute exposure to ETS based on cotinine levels in urine and clinically evaluated for their respiratory health by spirometry measurements and chestpiece auscultation. Effects of ETS exposure on genotoxic lesions were evaluated by measuring DNA/chromosomes breaks in peripheral blood lymphocytes and buccal mucosa cells. Effects of ETS exposure on plasma proteins is being studied using a 2D-DIGE-MALDI-TOF/TOF approach. To achieve that goal, global proteome characterization is being carried based on the same individual plasma samples collected for genotoxic studies and were pooled according to previous criteria. Results Results have confirmed higher respirable particle levels in smoking-designated areas of those entertainment places, indicating an ETS contamination. Leukocytes from ETS-exposed-workers presented lower levels of genotoxic-induced damage in comparison with non-exposed workers, suggesting an ETS-induced stress adaption response in exposed-workers. By proteomics, we are now to investigating those workers for putative alterations on their plasma proteome to provide additional insights on the adaptative response mechanisms that might be activated by ETS exposition. Conclusion Altogether, this study provides information on indoor air quality of Lisbon smoking entertainment places, in particular ETS contamination, and may provide biomarker candidates for occupational ETS-exposure which might precede respiratory diseases on their employees.
- Quantification of endocrine disruptors and pesticides in water using weighted linear regression schemesPublication . Melo, A.; Mansilha, C.; Pinho, O.; Ferreira, I.
- Application of chemometric methods to assess the impact of intensive horticulture practices on groundwater content of nitrates, sodium, potassium and pesticidesPublication . Pinto, E.; Melo, A.; Aguiar, A.; Mansilha, C.; Pinho, O.; Ferreira, I.
- Multi-residue analysis of 39 pesticides in surface waters of Ria de AveiroPublication . Vera, J.L.; Almeida, A.; Costa, J.M.; Domingues, V.F.; Delerue-Matos, C.; Mansilha, C.A multi-residue gas chromatography-mass spectrometry method was developed in order to evaluate the presence of 39 pesticides of different chemical families (organophosphorus, triazines, imidazole, organochlorine), as well as some of their transformation products, in surface water samples from Ria de Aveiro. Ria de Aveiro is an estuarine coastal lagoon, located in the northern west region of Portugal, which receives inputs from agriculture, urban and industrial activities. The analytical method was developed and validated according international guidelines and showed good linearity, with correlation coefficients higher than 0.9949 for all compounds, adequate precision and accuracy, and high sensitivity. Pesticides were chosen from the priority pollutants list of the Directive 2008/105/EC of the European Parliament and of the Council (on environmental quality standards in the field of water policy), or were selected due their common use in agricultural practices. Some of these 39 pesticides are, or are suspected to be, endocrine disruptor compounds (EDCs), being capable of altering the endocrine system of wildlife and humans, causing form malfunction and ultimately health problems. Even those pesticides which are not EDCs, are known to be awfully toxic and have a recognised impact in human health. The aquatic environment is particularly susceptible to pollution due to intentional and accidental release of chemicals to water [3]. Pesticide contamination of surface water is a national issue as it is often used as drinking water. This concern is especially important in rural agricultural areas where population uses small private water supplies, regularly without any laboratory surveillance. The study was performed in seven sampling points and the results showed a considerable concern pesticide contamination of all samples.