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- Potentially toxic elements dynamics in the soil rhizospheric-plant system in the active volcano of Fogo (Cape Verde) and interactions with human healthPublication . Candeias, Carla; Ávila, Paula Freire; Sequeira, Cristina; Albuquerque, Manuel; Rocha, FernandoABSTRACT: Volcanic eruptions disturb directly and indirectly the ecosystems. Direct impact occurs on the soil-plant system with an input of new elements and indirect hazard occurs by consumption of these plants. Fogo island (Cape Verde Republic) has an active volcano and the last eruption occurred in 2014-15, expelling large amounts of materials that spread all over the island. Soils and edible plants were collected all over the island. Pollution indexes reveal contamination in all samples, mostly due to Hg and Ni and with moderate contribution of Co, Cr, Cu and Pb. Mercury is the PTE with higher contribution to the non-carcinogenic hazard quotient, both by soil ingestion and inhalation. Carcinogenic risk exceeds the target risk in all samples with the higher contribution of Ni. Transfer factor from soils to plants decreasing order is Mn > As > Zn > Cr > Cu > Cd > Pb > Ni > Co > Hg, being < 1 except for As and Mn (TF > 1 point to a significant accumulation of elements in edible plants). The hazard risk index and targeted hazard quotient shows that potential negative health outcomes can be induced by As, Cr, Cu, and Zn by consumption of edible plants.
- A review of exposure assessment methods for epidemiological studies of health effects related to industrially contaminated sitesPublication . Hoek, Gerard; Ranzi, Andrea; Alimehmeti, Ilir; Ardeleanu, Elena-Roxana; Arrebola, Juan P.; Ávila, Paula Freire; Candeias, Carla; Colles, Ann; Crisan, Gloria Cerasela; Dack, Sarah; Demeter, Zoltan; Fazzo, Lucia; Fierens, Tine; Fluckiger, Benjamin; Gaengler, Stephanie; Hanninen, Otto; Harzia, Hedi; Hough, Rupert; Iantovics, Barna Laszlo; Kalantzi, Olga-Ioanna; Karakitsios, Spyros P.; Makris, Konstantinos C.; Martin-Olmedo, Piedad; Nechita, Elena; Nicoli, Thomai; Orru, Hans; Pasetto, Roberto; Perez-Carrascosa, F.M.; Pestana, Diogo; Rocha, Fernando; Sarigiannis, Dimosthenis A.; Teixeira, João Paulo; Tsadilas, Christos; Tasic, Visa; Vaccari, Lorenzo; Iavarone, Ivano; de Hoogh, KeesABSTRACT: BACKGROUND: this paper is based upon work from COST Action ICSHNet. Health risks related to living close to industrially contaminated sites (ICSs) are a public concern. Toxicology-based risk assessment of single contaminants is the main approach to assess health risks, but epidemiological studies which investigate the relationships between exposure and health directly in the affected population have contributed important evidence. Limitations in exposure assessment have substantially contributed to uncertainty about associations found in epidemiological studies. OBJECTIVES: to examine exposure assessment methods that have been used in epidemiological studies on ICSs and to provide recommendations for improved exposure assessment in epidemiological studies by comparing exposure assessment methods in epidemiological studies and risk assessments. METHODS: after defining the multi-media framework of exposure related to ICSs, we discussed selected multi-media models applied in Europe. We provided an overview of exposure assessment in 54 epidemiological studies from a systematic review of hazardous waste sites; a systematic review of 41 epidemiological studies on incinerators and 52 additional studies on ICSs and health identified for this review. RESULTS: we identified 10 multi-media models used in Europe primarily for risk assessment. Recent models incorporated estimation of internal biomarker levels. Predictions of the models differ particularly for the routes 'indoor air inhalation' and 'vegetable consumption'. Virtually all of the 54 hazardous waste studies used proximity indicators of exposure, based on municipality or zip code of residence (28 studies) or distance to a contaminated site (25 studies). One study used human biomonitoring. In virtually all epidemiological studies, actual land use was ignored. In the 52 additional studies on contaminated sites, proximity indicators were applied in 39 studies, air pollution dispersion modelling in 6 studies, and human biomonitoring in 9 studies. Exposure assessment in epidemiological studies on incinerators included indicators (presence of source in municipality and distance to the incinerator) and air dispersion modelling. Environmental multi-media modelling methods were not applied in any of the three groups of studies. CONCLUSIONS: recommendations for refined exposure assessment in epidemiological studies included the use of more sophisticated exposure metrics instead of simple proximity indicators where feasible, as distance from a source results in misclassification of exposure as it ignores key determinants of environmental fate and transport, source characteristics, land use, and human consumption behaviour. More validation studies using personal exposure or human biomonitoring are needed to assess misclassification of exposure. Exposure assessment should take more advantage of the detailed multi-media exposure assessment procedures developed for risk assessment. The use of indicators can be substantially improved by linking definition of zones of exposure to existing knowledge of extent of dispersion. Studies should incorporate more often land use and individual behaviour.
- Diferenças na intensidade de alteração química de sedimentos Pliocénicos a norte e sul do MondegoPublication . Oliveira, Álvaro; Dinis, Pedro A.; Rocha, FernandoProcede-se a uma análise comparativa de características mineralógicas e geoquímicas (elementos maiores), usadas na definição de intensidade de altyeração química, de sedimentos pliocénicos colhidos na margem Atlântica a norte e sul do rio Mondego. Ainda que se note alguma influência da granulometria dos sedimentos nas características composicionais, as unidades a norte do Mondego revelam sempre alteração química menos intensa que as unidades a sul do Mondego. Estas diferenças justificam-se por proveniência distinta e não devem ter qualquer significado climático.
- Metal(loids) bioaccessibility in road dust from the surrounding villages of an active minePublication . Candeias, Carla; Ávila, Paula Freire; Silva, Ferreira Da; Rocha, FernandoABSTRACT: Human activities, in general, cause a significant impact on the environment and human health. The present study aims to characterize the road dust of villages located near an active mine and to assess metal(loids) bioaccessible fractions. From the collected road dust samples (<250 µm fraction), the pseudo total, gastric (G) and gastrointestinal (GI) phase (UBM assay) concentrations, mineralogical composition, enrichment factor (EF), and risk for humans were determined. The obtained results revealed that arsenic represents the highest risk to humans, with mean pseudototal values higher than the maximum reference value range. The enrichment factor pointed to As as having significant to very high enrichment in all of the villages. In addition, Cd presented the maximum EF values in all of the villages, and was thus classified as having a very high enrichment. Particles enriched in As, Ca, Fe, Cu, Al, and Ti were identified by SEM-EDS in weathered agglomerates, and were linked to mine wastes and long-distance transport through both wind and/or traffic. The arsenic bioaccessibility fraction (%BAF) presented low values in the studied samples, possibly because of the low complex solubility of Fe with adsorbed As, limiting the release of arsenic and reducing its bioaccessibility. The concentrations of bioaccessible Cd for the G and GI phases were within the reference range, while for Cu, they were above and for Pb they were lower than the reference value range. The results show that the pseudototal fraction risk is overestimated when compared with BAF%; nevertheless, the total G and GI risks were above the carcinogenic target risk (1 × 10−6) in most of the samples. The carcinogenic risk of the bioaccessible contaminants showed that As represented the higher risk for developing cancer over a lifetime, with ingestion being the main risk route.
- Dust Characterization and Its Potential Impact during the 2014-2015 Fogo Volcano Eruption (Cape Verde)Publication . Candeias, Carla; Ávila, Paula Freire; Alves, Célia; Gama, Carla; Sequeira, Cristina; Silva, E. Ferreira da; Rocha, FernandoABSTRACT: Fogo (Fogo Island) is the youngest and most active volcano of Cape Verde. The last eruption occurred in 2014-2015. Aiming to assess the dust sources that impacted the air quality during the present study period, fresh lava samples were collected, while Saharan dust intrusions and transport were modeled. Rooftop dust was also collected on the island dwellings and a mineralogical and chemical characterization was undertaken. Air quality monitors were used to obtain concentrations of atmospheric particulate matter (PM) and gaseous pollutants. The mineralogical constitution was assessed by XRD and Electron Microprobe. The pseudototal chemical concentration was performed by XRF, ICP-MS and SEM; the latter includes particles morphology. During the study, WRF-CHIMERE results showed the intrusion of desert dust which affected the air quality. Lava was classified as tephritic to basanitic, with high potassium content. The Pollution Load Index for rooftop dust was > 1 in all samples, suggesting an enrichment. Higher values were found in dust size fraction < 63 mu m, with contamination factor pointing to high enrichment of As, Ni and Pb, and very high enrichment of Cd. The non-carcinogenic hazard estimated for children suggested that health problems may arise. The carcinogenic risk was above the target risk, mostly due to As > Pb > Co. Ingestion was the main exposure route. PM10 concentrations exceeded the 24-h mean of 50 mu g/m(3) recommended by WHO. Nevertheless, TVOCs displayed levels lower than guidelines. The highest levels of CO2 were recorded in more populated villages and farthest from the volcano.
- Mineralogia dos paleossolos e crostas carbonatadas do Cabo Mondego, PortugalPublication . Rocha, Fernando; Ramalho, Elsa
- Paleoenvironmental evolution of estuarine systems during the last 14000 years - the case of Douro Estuary (NW Portugal)Publication . Drago, Teresa; Freitas, Maria da Conceição; Rocha, Fernando; Moreno, João; Cachão, Mário; Naughton, Filipa; Fradique, Catarina; Araújo, Fátima; Silveira, T.; Oliveira, A.; Cascalho, João Pedro; Fatela, Francisco
- Geochemistry and mineralogy of Pliocene clay deposits from West Portugal : provenance signals?Publication . Oliveira, Álvaro; Dinis, Pedro A.; Rocha, Fernando
- Geochemical, mineralogical and morphological characterisation of road dust and associated health risksPublication . Candeias, Carla; Vicente, Estela; Tomé, Mário; Rocha, Fernando; Ávila, Paula Freire; Alves, CéliaABSTRACT: Road dust resuspension, especially the particulate matter fraction below 10 mu m (PM10), is one of the main air quality management challenges in Europe. Road dust samples were collected from representative streets (suburban and urban) of the city of Viana do Castelo, Portugal. PM10 emission factors (mg veh(-1) km(-1)) ranging from 49 (asphalt) to 330 (cobble stone) were estimated by means of the United Stated Environmental Protection Agency method. Two road dust fractions (<0.074 mm and from 0.0074 to 1 mm) were characterised for their geochemical, mineralogical and morphological properties. In urban streets, road dusts reveal the contribution from traffic emissions, with higher concentrations of, for example, Cu, Zn and Pb. In the suburban area, agriculture practices likely contributed to As concentrations of 180 mg kg(-1) in the finest road dust fraction. Samples are primarily composed of quartz, but also of muscovite, albite, kaolinite, microcline, Fe-enstatite, graphite and amorphous content. Particle morphology clearly shows the link with natural and traffic related materials, with well-formed minerals and irregular aggregates. The hazard quotient suggests a probability to induce non-carcinogenic adverse health effects in children by ingestion of Zr. Arsenic in the suburban street represents a human health risk of 1.58 x 10(-4).
- Terras raras nos sedimentos Pliocénicos entre os rios Vouga e Mondego (Portugal) = Rare earth elements in the Pliocene sediments between rivers Vouga and Mondego (Portugal)Publication . Oliveira, Álvaro; Dinis, Pedro A.; Santos, Rui Miguel P.; Rocha, FernandoA geoquímica de sedimentos argilosos do Pliocénico é usada para determinar as principais fases transportadoras de terras raras. Foram consideradas 3 fácies, associadas a sedimentação em planície de inundação e em pântano-lago, e dois sectores. A concentração de terras raras pesadas é substancialmente maior nos sedimentos de pântano-lago que nos de planície de inundação. Ainda que os minerais de argila integrem parte das terras raras, o xenótimo e a monazite são os principais minerais a transportar aqueles elementos. Outras fases (p. ex. matéria orgânica) em sedimentos de pântano-lago devem reter uma parte significativa das terras raras, em particular das terras raras pesadas. As concentrações de terras raras nos dois sectores não são muito diferentes, sugerindo que a proveniência era similar.