Chemical characterization, sources and potential health risk of PM2.5 and PM1 pollution across the Greater Athens Area.

With the principal aim to assess the typical Mediterranean profile of the PM2.5 and PM1 pollution, three intensive monitoring campaigns took place simultaneously within different types of environment across an urban location of the basin. Focusing on the PM components with numerous anthropogenic sources and increased potential health risk, the samples were chemically analyzed for 20 p.m.-bound Polycyclic Aromatic Hydrocarbons (PAHs). Carbonaceous and ionic constituents were quantified as well. In order to uncover the spatiotemporal variation of the PM profile the key sources were identified, the seasonal effects and the role of the prevailing mesoscale atmospheric circulation were evaluated and most importantly the potential health risk was estimated. In general, the pollution status of the basin was the result of a complex interaction between the local and external input with Particulate Organic Matter (POM) and Secondary Inorganic Aerosols (SIA) being the main aerosols' components. PM1 was a better indicator of the anthropogenic emissions while according to the results of factor analysis the co-existence of various combustion sources was determinant. Chemically, the maxima of the ΣPAHs, the differentiation of their structure in accordance with their molecular weight and the distribution of the individual compounds confirmed the significance of the emission sources. Similarly, the estimated carcinogenicity/mutagenicity was emission-dependent with the maximum contribution coming from B[a]P, IndP, B[ghi]Per, B[e]P and B[b]F. Seasonally, the highest potential health risk of the PAHs' mixture was recorded during the cold season while meteorologically, it was mostly associated with the south flow.

Assessing and enhancing the utility of low-cost activity and location sensors for exposure studies.

Nowadays, the advancement of mobile technology in conjunction with the introduction of the concept of exposome has provided new dynamics to the exposure studies. Since the addressing of health outcomes related to environmental stressors is crucial, the improvement of exposure assessment methodology is of paramount importance. Towards this aim, a pilot study was carried out in the two major cities of Greece (Athens, Thessaloniki), investigating the applicability of commercially available fitness monitors and the Moves App for tracking people's location and activities, as well as for predicting the type of the encountered location, using advanced modeling techniques. Within the frame of the study, 21 individuals were using the Fitbit Flex activity tracker, a temperature logger, and the application Moves App on their smartphones. For the validation of the above equipment, participants were also carrying an Actigraph (activity sensor) and a GPS device. The data collected from Fitbit Flex, the temperature logger, and the GPS (speed) were used as input parameters in an Artificial Neural Network (ANN) model for predicting the type of location. Analysis of the data showed that the Moves App tends to underestimate the daily steps counts in comparison with Fitbit Flex and Actigraph, respectively, while Moves App predicted the movement trajectory of an individual with reasonable accuracy, compared to a dedicated GPS. Finally, the encountered location was successfully predicted by the ANN in most of the cases.

Effect of Robola and Cabernet Sauvignon extracts on platelet activating factor enzymes activity on U937 cells.

A number of studies support the anti-atherogenic effect of wine compounds. The scope of this study was to examine the effect of a red (Cabernet Sauvignon-CS) and a white (Robola-R) wine, as well as resveratrol and quercetin, on the platelet activating factor (PAF) biosynthetic enzymes, acetyl-CoA:lyso-PAF acetyltransferase (lyso-PAF-AT) and DTT-insensitive CDP-choline 1-alkyl-2-acetyl-sn-glycerol cholinephosphotransferase (PAF-CPT), and its main catabolic enzyme (PAF acetylhydrolase; PAF-AH), on U937 cells, in cell free and in intact cell experiments. In cell free experiments, phenolic compounds and wine extracts inhibited PAF biosynthetic enzymes, however in higher concentrations than intact cell experiments. In the latter cases, polar lipids of both wines inhibited in the same order of magnitude the action of lyso-PAF-AT and of PAF-CPT. The water fractions possessed a dual action, in lower concentrations they activated both enzymes, while in higher concentrations only inhibited PAF-CPT. All fractions either did not affect or slightly activated PAF-AH activity. In conclusion, wine compounds may exert their anti-inflammatory activity by reducing PAF levels through modulation of the PAF metabolic enzymes.

Assessment of PM2.5 and PM1 chemical profile in a multiple-impacted Mediterranean urban area: origin, sources and meteorological dependence.

Airborne particulate matter in the PM2.5 and PM1 size ranges has been sampled at three sites within the Mediterranean urban area of the Athens Basin, representing background, roadside-industrialized and coastal background locations. With the principal aim to identify the sources and discriminate the contribution of the regional input versus the local one, simultaneous chemical characterization with respect to carbonaceous and ionic species was also carried out on the collected samples. In general, the average recorded values were within the Mediterranean concentration range. The constant prevalence of the ionic mass (52%-79%) over one of the carbonaceous, being combined with the occurrence of its maximum rates at the coastal background environment (74%-79% and 73%-77% for PM2.5 and PM1, respectively) leads to the hypothesis that the fine PM pollution in the basin, especially for the remote locations, is evidently governed by the external intrusion. Even at the polluted atmosphere of the roadside-industrialized environment, the PM mass was regionally originated, with the corresponding input reaching up to 87% (northward flow). Applying factor analysis on the PM2.5 database it came obvious that the sources which were responsible for the configured PM burden were not fully differentiated not only between the different types of environment but also between the exceedances and the clean air events. The contribution of the secondary, marine and combustion processes was constant at all the stations of the network, while a continuous input of crustal particles characterized both the roadside-industrialized and the coastal atmosphere. Finally, the episodic values show a general common signal of secondary mixed ΡΜ emissions, high influence of both regional and local pollution spikes, confirming the earlier findings for the significance of transportation.

The new Greek national e-prescription system: an effective tool for improving quality of care and containing medication costs.

The national e-prescription system of Greece was first introduced in 2010 and already covers more than 80% of all prescriptions prescribed today (more than 5 million per month). Its introduction provided a powerful tool for improving patient services and public health planning. The system is also already a valuable source of planning, control and transparency data for the Greek healthcare system. In addition, the experience from its application at national level in Greece has also shown that e-Prescription systems can also provide a very useful tool for better administrative control and for containing unnecessary expenditure related to medication use.

The role of meteorology on different sized aerosol fractions (PM10, PM2.5, PM2.5-10).

The scope of the present study is to assess the influence of meteorology on different diameter particles (PM(10), PM(2.5), PM(2.5-10)) during a 53 months long experimental campaign at an urban Mediterranean area. Except for the investigation of the wind, temperature and relative humidity role, day by day synoptic conditions were classified over the Attica peninsula in order to explore as well, the role of the synoptic scale atmospheric circulation. The strong dependence of the aerosols character on their various sources, not only explain the different diameter particles behavior and their differentiation with the inorganic pollutants but also highlights the need for an effective emission policy. High PM(10) and PM(2.5-10) concentrations found to be closely related to the southwesterly regime, suggesting long range transport from the 'polluted' south sector while the general prevalence of the secondary particles generation revealed the health hazard. PM(2.5) showed a weaker correlation than the bigger particles with both the circulation patterns and the parameters' fluctuations. Temporal pollutants variations were clearly governed by the emissions patterns while the low wind speed was not necessarily a good indicator of high concentration levels. Finally it was found that only during the open/close anticyclonic days and the southwesterly wind regime the morning levels were continuously higher than those of the night.

Particulate matter levels in a suburban Mediterranean area: analysis of a 53-month long experimental campaign.

Parallel measurements of ambient particulate matter mass in terms of PM(10), PM(2.5) and PM(2.5-10), conducted during a 53 months long experiment, between 2003 and 2008. The data constituting one of the longest simultaneous comparative data sets for the three PM fractions in Europe, collected at a suburban area of Athens, Aghia Paraskevi. Total means of mass concentrations for PM(10), PM(2.5) and PM(2.5-10) were in the order of 34.8, 18.0 and 23.8 microg/m(3), respectively. Seasonal variability of PM levels governed by the fact that the specific site is dominated by secondary aerosol emissions with the concentrations presenting a shift to the warm period. During the whole sampling period PM(10) were mainly composed of PM(2.5) while particles with the bigger diameter proved to be strongly correlated in all the cases. It would be interesting to mention that all the three aerosol fractions did not present any association with the inorganic pollutants. Stagnant conditions as well as the wind direction proved to be key mechanisms for the configuration of the air quality patterns. Saronic Gulf sea-breeze development enhanced the aerosol transportation from the industrialized greater area of Piraeus and the polluted center of the city, to the Northern suburbs.

Ions species size distribution in particulate matter associated with VOCs and meteorological conditions over an urban region.

Airborne particulate matter (PM10, PM2.5, PM1) and volatile organic compounds (benzene, toluene, m,p-xylene, o-xylene) samples were collected during winter and summer seasons of 2005 at two sites, representing an urban and a suburban region of the Greater Athens Area. Urban site traffic emissions were the major contributor to the concentration of PM2.5, PM10, toluene, and xylenes, while benzene and PM1 concentrations were presented in significant spatial variations. K+, Na+, Mg2+, Ca2+, NO3-, Cl- and SO42- ions were analyzed for the chemical characterization of the collected PM samples. The results showed that Na+ cations and SO42- anions were the dominant species, during winter and summer, respectively, in both sites. The analysis of the synoptic scale and mesoscale atmospheric circulation during the experimental periods demonstrated that the meteorological conditions play a key role, not only in the variation but also in the distribution of the ionic concentrations at the three fractions of particulates and the dominant character (alkaline/acidic/neutral) of the particulates at the two sampling sites.

Lung deposition of fine and ultrafine particles outdoors and indoors during a cooking event and a no activity period.

UNLABELLED: Some indoor activities increase the number concentration of small particles and, hence, enhance the dose delivered to the lungs. The received particle dose indoors may exceed noticeably the dose from ambient air under routine in-house activities like cooking. In the present work, the internal dose by inhalation of ultrafine and fine particles is assessed, using an appropriate mechanistic model of lung deposition, accommodating aerosol, and inhalation dynamics. The analysis is based on size distribution measurements (10-350 nm) of indoor and outdoor aerosol number concentrations in a typical residence in Athens, Greece. Four different cases are examined, namely, a cooking event, a no activity period indoors and the equivalent time periods outdoors. When the cooking event (frying of bacon-eggs with a gas fire) occurred, the amount of deposited particles deep into the lung of an individual indoors exceeded by up to 10 times the amount received by an individual at the same time period outdoors. The fine particle deposition depends on the level of physical exertion and the hygroscopic properties of the inhaled aerosol. The dose is not found linearly dependant on the indoor/outdoor concentrations during the cooking event, whereas it is during the no activity period. PRACTICAL IMPLICATIONS: The necessity for determining the dose in specific regions of the human lung, as well as the non-linear relationship between aerosol concentration and internal dose makes the application of dosimetry models important. Lung dose of fine and ultrafine particles, during a cooking event, is compared with the dose at no indoor activity and the dose received under outdoor exposure conditions. The dose is expressed in terms of number or surface of deposited particles. This permits to address the dosimetry of very small particles, which are released by many indoor sources but represent a slight fraction of the particulate matter mass. The enhancement of the internal dose resulting from fine and ultrafine particles generated during the cooking event vs. the dose when no indoor source is active is assessed. The results for those cases are also compared with the dose calculated for the measured aerosol outdoors.

The use of a complex thermohygrometric index in predicting adverse health effects in Athens.

Mortality and morbidity indices are known to depend on changes in meteorological conditions. In Athens, severe adverse health effects following extreme heat conditions have been reported. The usefulness has been investigated of the complex thermohygrometric index (THI), a simple index based on maximum daily temperature and relative humidity, in predicting the health effects of specific meteorological conditions. The values of THI were found to correlate well with more complex bioclimatic indices; the THI could successfully replace temperature and humidity in predicting the daily number of deaths through multiple linear regression modelling. Thus the introduction of THI levels more than 28.5 degrees C and between 26.5 and 28.5 degrees C, through dummy variables, in a regression model explained 40% of the variability in the number of deaths during the months of July and August. During days with THI values less than 26.5 degrees C the mean number of deaths was 33.5, compared to 41.8 when THI was between 26.5 and 28.5 degrees C. The daily number of deaths increased to 108.2 when THI exceeded 28.5 degrees C. From this study, the exact level of THI at which public health measures must be taken was not clear and more work is needed to identify it. However, given its simplicity, the use of THI for predicting meteorological conditions which are adverse to health would appear to be promising in preventive medicine and in health services planning.

Evidence for interaction between air pollution and high temperature in the causation of excess mortality.

Studies have demonstrated repeatedly that air pollution in Athens is associated with a small but statistically significant increase in mortality. Extremely high air temperatures can also cause excess mortality. This study investigated whether air pollution and air temperature have synergistic effects on excess mortality in Athens. Data concerning the increased number of deaths in July 1987 (when a major "heat wave" hit Greece) were compared to the deaths in July of the 6 previous years. This comparison revealed a greater increase in the number of deaths in Athens (97%), compared to all other urban areas (33%) and to all non-urban areas (27%). Data on the daily levels of smoke, sulfur dioxide, and ozone; the number of deaths that occurred daily; and meteorological variables were collected for a 5-y period. The daily value of Thom's discomfort index was calculated. Multiple linear regression models were used to investigate main and interactive effects of air temperature and Thom's discomfort index and air pollution indices. The daily number of deaths increased by more than 40 when the mean 24-h air temperature exceeded 30 degrees C. The main effects of an air pollution index are not statistically significant, but the interaction between high levels of air pollution and high temperature (> or = 30 degrees C) are statistically significant (p < .05) for sulfur dioxide and are suggestive (p < .20) for ozone and smoke. Similar results were obtained when the discomfort index was used, instead of temperature in the models.

Middle ear function in patients with juvenile chronic arthritis.

The conductive hearing of 18 patients with juvenile chronic arthritis was studied. Tympanometry was therefore undertaken for the assessment of functional state of the tympanic membrane, the ossicular chain with its ligaments and muscles, and the air cushion of the tympanic cavity. Acoustic reflex was present in all patients but an abnormal tympanometric pattern (type As) was found bilaterally or unilaterally in 10 (mostly severe cases) patients. These findings indicate that juvenile chronic arthritis changes middle ear function, probably as a result of inflammation of the synovial ossicular joints, which is followed by stiffness of the tympanic membrane and ossicular chain.