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- 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.
- Passive monitoring of particulate matter and gaseous pollutants in Fogo Island, Cape VerdePublication . Alves, Célia; Candeias, Carla; Nunes, Teresa; Tomé, Mário; Vicente, Estela; Ávila, Paula Freire; Rocha, FernandoABSTRACT: An air quality monitoring campaign by passive sampling techniques was carried out, for the first time, between November 2016 and January 2017 on the Cape Verdean island of Fogo, whose volcanic mountain rises up to 2829 m. Levels of SO2 and acid gases (HF, HCl, HNO3, H2SO4 and H3PO4) were, in most cases, below the detection limits. Alkylpentanes, hexane, cycloalkanes and toluene were the dominant volatile organic compounds. The m,p-xylene/ethylbenzene ratios revealed that air masses arriving at Cape Verde have been subjected to significant aging processes. High toluene/benzene ratios suggested extra sources of toluene in addition to vehicle emissions. Deposition rates of total settleable dust ranged from 23 to 155 mg/m(2)/day. On average, organic carbon accounted for 15.6% of the dust mass, whereas elemental carbon was generally undetected. Minerals comprised the dominant mass fraction. The dust levels were mostly affected by two main airflows: the westerlies and the Saharan Air Layer. These air masses contributed to the transport of mineral dust from desert regions, secondary inorganic constituents (SO42-, NO3- and NH4+) and tracers of biomass burning emissions, such as potassium. Sea salt represented 12% of the mass of settleable dust. Scanning electron microscope observations of several particles with different compositions, shapes and sizes revealed high silica mass fractions in all samples, as well as variable contents of carbonates, sulphates, aluminosilicates, Fe, Ti, F and NaCl, suggesting that, in addition to the already mentioned sources, dust is likely linked to industrial emissions in the northern and north-western coast of the African continent. Although some atmospheric constituents presented higher concentrations near the crater, the small fumarolic activity still present after cessation of the eruption in February 2015 has a limited impact on air quality, which is most affected by long range transport and some local sources at specific locations.
- NewSOL Project: Implementation and validation tests for Fluent : Case 0Publication . Seram, Victor; Lima, Maria Margarida de Lemos Canedo Giestas; Azevedo, PedroABSTRACT: The present report was made according to the implementation of “Fluent: Case 0”1 of the NewSol Project (Grant nº 720985). The Ansys computational package software was used for the conducted simulations. A 2D geometry symmetrical at the middle axis was constructed. Several meshes were both made and simulated for the minimum computational cost. For simplicity of the problem and at this early stage of development of the model, the ullage space was taken to be filled with HTF (Heat Transfer Fluid). Although HTF fills the ullage space in the tank, this is not in good agreement with the condition described in Case 0 which considers air as the medium. All the simulations were performed with steady state conditions. However, in the future transient state would be used.