Scientists in the last decades have precisely manipulated chemical atoms and molecules for fabrication of macroscale products with a wide range of applications. Nanotechnology emerged as one of the promising technologies in the 21st century. Engineered nanomaterials (ENMs) provided a wide range of applications for pharmaceutical and biomedical products. After years of intensive research ENMs advanced rapidly for various technological applications because of their unique minute size, optical, electronic, magnetic, mechanical and chemical properties. Pharmacology and biomedical applications, especially, stand to benefit from obvious opportunities presented by nanomaterials. Because of their extraordinarily small dimensions, nanoscale substances are capable of venturing effortlessly in internal parts of the human body. ENMs can be designed from biocompatible and biodegradable constituents, and used to enhance the stability of otherwise fragile therapeutic drug molecules. They can improve drug solubility and bioavailability; enhance therapeutic molecule stability, and direct delivery of therapeutics to specific sites of action. Also, ENMs can be used for biomolecular sensing, molecular imaging of tumours and their stages of development. These properties will ensure the importance of nanomaterials to the design and delivery of medicinal substances for the foreseeable future. This review presents the most significant applications of nanoproducts in pharmacology and biomedicine, through selective scientific papers and reviews of the last decade. Also, the review covers the issues of health and safety from exposure to nanoproducts for workers, medical professionals and consumers.

Scientists in the last decades have precisely manipulated chemical atoms and molecules for fabrication of macroscale products with a wide range of applications. Nanotechnology emerged as one of the promising technologies in the 21st century. Engineered nanomaterials (ENMs) provided a wide range of applications for pharmaceutical and biomedical products. After years of intensive research ENMs advanced rapidly for various technological applications because of their unique minute size, optical, electronic, magnetic, mechanical and chemical properties. Pharmacology and biomedical applications, especially, stand to benefit from obvious opportunities presented by nanomaterials. Because of their extraordinarily small dimensions, nanoscale substances are capable of venturing effortlessly in internal parts of the human body. ENMs can be designed from biocompatible and biodegradable constituents, and used to enhance the stability of otherwise fragile therapeutic drug molecules. They can improve drug solubility and bioavailability; enhance therapeutic molecule stability, and direct delivery of therapeutics to specific sites of action. Also, ENMs can be used for biomolecular sensing, molecular imaging of tumours and their stages of development. These properties will ensure the importance of nanomaterials to the design and delivery of medicinal substances for the foreseeable future. This review presents the most significant applications of nanoproducts in pharmacology and biomedicine, through selective scientific papers and reviews of the last decade. Also, the review covers the issues of health and safety from exposure to nanoproducts for workers, medical professionals and consumers.

Greece has in its territory 45 rivers (of which 21 are major rivers) and 40 lakes with a total surface of approximately 560 km 2 . Also, Greece has excellent wetlands with important and rich ecosystems. Four of the longest flowing rivers in Greece are the Evros, Nestos, Strymonas and Axios and the Axios have their springs in the northern Balkan countries. The longest Greek rivers are Aliaknon, Acheloos, Pinios in Thessaly, Evros and Nestos. There are natural and artificial lakes in Greece, as well as many lagoons. Most lakes are freshwater and have formed mainly far from the coastlines as a result of tectonic or volcanic forces, or from the melting of glaciers. Greece in order to secure adequate fresh water from the rivers throughout the annual circle constructed numerous damns and artificial lakes in the most important rivers. It is known from studies that water from rivers and lakes is used excessively for agricultural use, for drinking water of cities and towns and for the generation of electricity. The biggest natural lake is Trichonida and the largest artificial is Lake Kremaston. Studies of the last decades showed that the water levels of lakes is lowering continuously (Vegoritida, Koronia, Doirani, etc). The most important factor is the excessive use of their water for farming, the reduction of rain seasons and climatic changes. Also, erosion of soil surrounding lakes precipitates in the bottom reducing their sizes. Rivers, lakes and wetlands are polluted by liquid urban waste especially produced by highly populated cities and towns. Most of the major Greek rivers are characterized by point-pollution sources which are mainly concentrated near urban centres, as well as extensive arable areas. Pollution of rivers, lakes and lagoons is the result of excessive use of fertilizers as well as pesticides. Nutrient concentrations from agricultural activities in major Greek rivers has been an important pollution issue. High nitrate and phosphate, nitrite and ammonium concentrations can be found in all major Greek rivers. Heavy metals in rivers and lakes is another serious environmental problem. Cadmium, mercury, lead, nickel and copper concentrations have been measured in major Greek rivers. Regarding lead, nickel copper and zinc, their levels in Greek rivers are in general higher. In the last decades other pollutants, such as toxic chemicals and endocrine disrupting substances have been measured in Greek rivers and lakes. Liquid waste from stock farming activities is another important environmental problem. Pollution of rivers, lakes and lagoons is the result of washing and leachates from illegal urban and industrial solid waste tips. Crude petrol and toxic substances from industrial waste has been found in many rivers and lakes. Transboundary pollution of Axios from the northern Balkan countries is a serious issue. Water quality in the rivers Aliakmonas and Axios is influenced by liquid waste from highly populated areas and industrial facilities. Loudias river, because of agricultural effluents and liquid waste from food and sugar industrial activities, has been the most polluted river. In this review the most important environmental and pollution issues are presented in a comprehensive way from scientific studies and reports of the last decades and the preventative measures to reduce pollution and protect water quality and freshwater ecosystems.

Ambient air pollution in urban and industrial areas in Greece was a serious environmental problem which was connected with rapid urbanization of cities, anarchic housing development without basic infrastructures and increases of motor vehicle fleet in urban regions. Especially Athens, witnessed severe air pollution problems in the decades 1960s‘-1970s‘ and the formation of the infamous brown-yellow ―nephos‖ in Athens. But in recent years the air quality in Greece has greatly improved in most urban areas because of the better fuels and replacement of the polluting vehicles of old technology. In Athens and Thessaloniki, the ambient levels of coarse smoke, CO, SO2, NOx (NO2, NO), O3 and Pb were reduced substantially below air quality limits. In Athens and Thessaloniki air pollution was characterized by high concentrations of airborne particulate matter (PM) of carbonaceous particles and photochemical smog –which was linked to an excess of nitrogen oxides, hydrocarbons, carbon monoxide (primary pollutants), ozone, and organic nitrates (secondary pollutant) as a result from a series of chemical reactions driven by sunlight. The primary pollution sources were vehicular traffic, central heating, industrial facilities and small enterprises. In the past decades several environmental legislations were undertaken in an effort to improve the existing air quality conditions in urban areas. Replacement of old vehicles (1991), new cars equipped with catalytic converters, replacement of the old buses equipped with anti-pollution devices and natural gas for heating and energy generation was introduced. Environmental legislation was enacted for the abatement of industrial pollution and smoke and energy efficiency measures. Abatement practices reduced substantially primary pollutants (SO2, NOx, CO, smoke) and secondary (O3). The economic crisis of the last five years (2010-2015) affected the prices of heating oil and forced some families to use low-cost wood and biomass as fuel for fire places and stoves (the later dropped in international prices of petrol reduced financial constrains in the use of oil for heating, while the 2014-2015 winter months were mild and air pollution episodes were limited).The result was smoke haze and high levels of airborne particulates (fine and superfine) during the evenings and morning hours of the day in Athens, Thessaloniki and other cities. Airborne particular matter (PM) from burned wood are dangerous because of their toxic organic constituents (polycyclic aromatic hydrocarbons, PAH), free radicals and metals. This review collected some of the most important studies on air pollution in urban areas and the consequences of economic crisis in Athens and other cities. Also, studies on air pollution in areas with lignite-fired power stations were included. Air pollution causes adverse health effects, respiratory diseases (hospitalization), and increased mortality in the last decade (in the years before after the economic crisis). Adverse health effects on urban dwellers in major cities of Europe cities were investigated by multicenter panes of researchers. The results showed that Athens and Thessaloniki have some of the highest levels of air pollutants and PM (PM10, PM2.5). Epidemiological studies in European cities have documented associations between outdoor exposure to air pollutants biomass combustion products and a range of adverse health effects. The present review covers the most important research papers on the air pollution trends in major urban areas, the results of economic crisis in the use of biomass fuel. Also, this review includes studies and investigations for the association of air pollutants (especially PM) with adverse health effects, in particular respiratory diseases, and increased mortality in urban areas.

Nanotechnology ant its applications has emerged as one of the central new technologies in the 21st century. In the last decade thousands of scientists and technologists are employed in this area, a great number of patents and scientific publications have been publishedAlarge number of new nanotechnology products have flooded the market of the developed world and inevitably large amounts of money are invested in Research & Development in themost advanced technological nations. Future prospects in different fields of nano-applications seemunlimited and its high potential will affect our daily life, our health and the environment in the years to come. Nanomaterials found applications in the fields of consumer products (cosmetics, textiles, diagnostic materials, personal care products, paints, etc), food, energy, medicines, computers, portable telephones and a great variety of other scientific fields. But in recent years, scientists and environmentalists are thinking about possible hazards to human health resulting fromnanoparticulate exposures in theworking environment, after contact with consumer products and through environmental pollution. The requirements for appropriate health risk assessment and safety regulations of nanomaterials are being explored.Also, environmental pollution and the fate of nanomaterials in the natural environment, especially in the aquatic environment, are some of the great concerns to scientists and environmentalists. In this paper we present an overall reviewof the current state of knowledge related to toxicity and human health risk of the engineered nanoparticles. The review presents the latest research papers on newchallenges facing scientists and technologists with nanaomaterials. Furthermore, the review examines the future requirements for making nanotechnology safe for the consumer, the industrial worker and less polluting for the environment and the ecosystems. Based on the current toxicological results, scientists provide a proposal on how risk assessment in the nanofield could be achieved and how it might look like in the near future.

The present review describes the role of different energy regimes throughout the human history and their environmental impact.The appearance of Homo sapiens and the development of primitive human civilization can be narrated by different energy regimes throughout the centuries.Getting the energy that humans needed for their needs affected directly the environment in many different ways.Some energy sources have a greater impact than others.Energy is lost to the environment during any energy transformation, usually as heat.Environmental historian can describe human history, from the discovery of fire (the most important human invention) by the primitive man and the development in four different energy regimes over the last ten thousand years.The first two divisions, "gatherer-hunters" (1.5 million to 10,000) and "pre-industrial agriculture," cover many centuries until 1750.The third period deals with "an industrial world" up to 1950, and the fourth period covers the developments in the post industrial society, between 1950 and the 21 st century.Energy usage divides periods of socio-ecological human history.In each period, human energy sources and consumption changed significantly, providing a point of no return.Until the 1700s, however, agriculture continued to rely on energy directly related to the sun and stored in organic systems.After 1750, humans developed new ways of thinking about nature, as well as new kinds of energy systems based on coal and the production of steam.New energy systems (petroleum, natural gas, hydroelectric) allowed a dramatic increase in human populations but at the same time polluted quite heavily damaging the environmental balance with nature.Those increases changed dramatically after 1950 and caused the doubling of the population and the multiple energy use for transport and electricity.Are nuclear energy and renewable energy sources the future prospects for a sustainable development in energy use by humans?Is the -Third Industrial Revolution‖ the future solution for global warming?These are hard questions with great implications on the future of the planet, its ecological balance and inevitably for the human civilization.

Plant polyphenols are considered among the most abundant phytochemicals that are present in human diets, and their regular consumption has been associated with reduced risk of a number of chronic diseases, including cancer, and cardiovascular and neurodegenerative disorders. In the past decades, plant polyphenols have drawn increasing scientific attention due to their potent antioxidant and other properties and their marked effects in the prevention of various oxidative stress-associated diseases. Recently, the polyphenolic extracts from different plants have become a major area of health- and medical-related research. This review provides an update and comprehensive overview of various plant polyphenolic compounds, and the quantification of their antioxidant properties, anticancer activities, and therapeutic effects. Also, the review discusses the current scientific knowledge of various plant polyphenols to inhibit tumorigenesis in animal models and to modulate cell signaling pathways involved in inflammation and the development of malignant tumors, and related biochemical interventions in cell function under both normal and pathological conditions. We present in vitro and in vivo studies (in experimental animals) in which polyphenols showed increased anticancer potential. Also, numerous epidemiological research data and findings from human intervention studies, as well preclinical studies supporting cancer prevention mechanisms. Lastly, we present recent clinical trials for anticancer action of certain polyphenols that showed promising anticancer and therapeutic properties.

Reactive oxygen or nitrogen species (ROS, RNS) and oxidative stress in the respiratory system increase the production of mediators of pulmonary inflammation and initiate or promote mechanisms of carcinogenesis. The lungs are exposed daily to oxidants generated either endogenously or exogenously (air pollutants, cigarette smoke, etc.). Cells in aerobic organisms are protected against oxidative damage by enzymatic and non-enzymatic antioxidant systems. Recent epidemiologic investigations have shown associations between increased incidence of respiratory diseases and lung cancer from exposure to low levels of various forms of respirable fibers and particulate matter (PM), at occupational or urban air polluting environments. Lung cancer increases substantially for tobacco smokers due to the synergistic effects in the generation of ROS, leading to oxidative stress and inflammation with high DNA damage potential. Physical and chemical characteristics of particles (size, transition metal content, speciation, stable free radicals, etc.) play an important role in oxidative stress. In turn, oxidative stress initiates the synthesis of mediators of pulmonary inflammation in lung epithelial cells and initiation of carcinogenic mechanisms. Inhalable quartz, metal powders, mineral asbestos fibers, ozone, soot from gasoline and diesel engines, tobacco smoke and PM from ambient air pollution (PM10 and PM2.5) are involved in various oxidative stress mechanisms. Pulmonary cancer initiation and promotion has been linked to a series of biochemical pathways of oxidative stress, DNA oxidative damage, macrophage stimulation, telomere shortening, modulation of gene expression and activation of transcription factors with important role in carcinogenesis. In this review we are presenting the role of ROS and oxidative stress in the production of mediators of pulmonary inflammation and mechanisms of carcinogenesis.

Urban air pollution has been one of the most important pollution problem for many decades. Airborne particulate matter (PM) from combustion sources is considered the most important air pollutants for adverse health effects to humans, especially for acute and chronic respiratory diseases and lung cancer. Airborne particles contain a number of toxic and carcinogenic substances as well as persistent free radicals entering the lung’s alveoli. PM in the lungs can generate free radicals and reactive oxygen species (ROS), initiating mechanisms of oxidative stress, inflammation and mutagenic damage to cellular DNA. These conditions lead progressively to increased morbidity and mortality as well as to increased risk of lung cancer. In the last decades a number of studies investigated PM size focusing to PM with aerodynamic diameter below l0 μm (ΡM10 and ΡΜ2.5), transition metals, polycyclic aromatic hydrocarbons (ΡΑΗ), stable quinoids αnd carcinogenic nitropyrenes. ROS generated by PM are linked to the pathogenesis of pulmonary oxidative damage, lipid peroxidation, damages to enzymes and cellular DNA. In our experimental study we investigated ROS generation by airborne PM (exhaust soot diesel and gasoline) by Electron Paramagnetic Resonance (EPR) and persistent free radicals characteristic to a mixture of semiquinone radicals. Also, we examined by EPR the formation of oxidative damage to guanosine nucleobase. by PM in aqueous phosphate buffer (pH 7.4) and the formation of the cancer biomarker 8-hydroxy-2’-deoxyguanosine.

Engineered nanomaterials (ENMs) are a diverse group of materials finding increasing use in manufacturing, computing, food, pharmaceuticals, and biomedicine due to their very small size and exceptional properties. Health and safety concerns for ENMs have forced regulatory agencies to consider preventive measures and regulations for workers' health and safety protection. Respiratory system toxicity from inhalable ENMs is the most important concern to health specialists. In this review, we focus on similarities and differences between conventional microparticles (diameters in mm and μm), which have been previously studied, and nanoparticles (sizes between 1 and 100 nm) in terms of size, composition, and mechanisms of action in biological systems. In past decades, respirable particulate matter (PM), asbestos fibers, crystalline silicate, and various amorphous dusts have been studied, and epidemiological evidence has shown how dangerous they are to human health, especially from exposure in working environments. Scientific evidence has shown that there is a close connection between respirable PM and pulmonary oxidative stress through the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). There is a close connection between oxidative stress in the cell and the elicitation of an inflammatory response via pro-inflammatory gene transcription. Inflammatory processes increase the risk for lung cancer. Studies in vitro and in vivo in the last decade have shown that engineered nanoparticles (ENPs) at various doses can cause ROS generation, oxidative stress, and pro-inflammatory gene expression in the cell. It is assumed that ENPs have the potential to cause acute respiratory diseases and probably lung cancer in humans. The situation regarding chronic exposure at low doses is more complicated. The long-term accumulation of ENPs in the respiratory system cannot be excluded. However, at present, exposure data for the general public regarding ENPs are not available.

Ambient airborne particulate matter (PM) is considered as the most important pollutant for adverse health effects in the human respiratory system. PM is known to contain a large number of toxic and carcinogenic substances which in the lung’s alveoli cause oxidative stress, inflammation and cytotoxic damage leading to malignant neoplasms. Studies in recent years focused on transition metals, polycyclic aromatic hydrocarbons (PAH), stable quinoid and carbonaceous radicals. In the presence of oxygen and through redox reactions PM promote the production of reactive oxygen species (ROS), especially hydroxyl radicals (HO•), which are linked to lipid peroxidation and oxidative damage to peptides and cellular and mitochondrial DNA. In this study we investigated the most important mechanisms of ROS generation from airborne traffic-related PM, and exhaust soot from diesel and gasoline vehicles (DEP, GEP). Using Electron Paramagnetic Resonance (EPR) we examined the presence of persistent quinoid free radicals and we studied the direct production of superoxide anion (O 2 •− ), hydrogen peroxide (H2O2) and the damaging hydroxyl radicals (HO•) by PM extracts. Also, we examined by EPR the formation of oxidative damage to guanosine nucleobase by PM in aqueous phosphate buffer (pH 7.4). Experimental evidence shows that redox-active transition metals, persistent redox-cycling quinoids, and PAHs contained in the PM act synergistically, producing ROS. These ROS are considered the main mechanisms for the cytotoxic and carcinogenic potential of PM, leading to oxidative stress, pulmonary tissue injuries and DNA damage.

Airborne particulate matter (PM) from various combustion emission sources is considered as the most important pollutant for adverse health effects in the respiratory system. There is a large number of toxic and carcinogenic substances from airborne particulate matter entering the lung's alveoli which cause oxidative stress, inflammation and cytotoxic damage. These conditions lead progressively to increased morbidity and mortality as well as to increased risk to lung cancer. Studies investigated their size and Physicochemical characteristics, focusing especially to fine particulate matter with aerodynamic diameter below 10 mu m (PM10 and PM2,5), their transition metals, polycyclic aromatic hydrocarbons (PAH), stable quinoids and carcinogenic nitropyrenes. Fine particles enter the lungs and because of their small size are trapped in the alveoli and pulmonary tissues, where toxic substances in the presence of oxygen and redox reactions promote the production of reactive oxygen species (ROS) especially hydroxyl radicals, which are linked to the pathogenesis of pulmonary and cardiovascular adverse effects causing lipid peroxidation, damages to peptides and cellular DNA. In this Study we investigated the problem of ROS generation from airborne PM, exhaust soot (diesel and gasoline) and soot from burned wood. Additionally, using Electron Paramagnetic Resonance (EPR) we examined the persistent free radicals in various samples, characteristic to a mixture of semiquinone radicals. Also, we Studied the direct production of superoxide anion (O-2(center dot-)), hydrogen peroxide (H2O2) and the damaging hydroxyl radicals (HO center dot) by various extracts of particulate matter. Finally, we examined by EPR the formation of oxidative damage to guanosine nucleobase by PM ill aqueous phosphate buffer (pH 7.4). From these results, it was suggested that the cytotoxic and carcinogenic potential of PM is the result of redox cycling of persistent quinoid radicals and transition metal ions on the surface of particles in the generation of ROS with potential for oxidant injurious effects in pulmonary tissues.

There is extensive experimental evidence that oxidative damage permanently occurs to lipids of cellular membranes, proteins, and DNA. In nuclear and mitochondrial DNA, 8-hydroxy-2' -deoxyguanosine (8-OHdG) or 8-oxo-7,8-dihydro-2' -deoxyguanosine (8-oxodG) is one of the predominant forms of free radical-induced oxidative lesions, and has therefore been widely used as a biomarker for oxidative stress and carcinogenesis. Studies showed that urinary 8-OHdG is a good biomarker for risk assessment of various cancers and degenerative diseases. The most widely used method of quantitative analysis is high-performance liquid chromatography (HPLC) with electrochemical detection (EC), gas chromatography-mass spectrometry (GC-MS), and HPLC tandem mass spectrometry. In order to resolve the methodological problems encountered in measuring quantitatively 8-OHdG, the European Standards Committee for Oxidative DNA Damage was set up in 1997 to resolve the artifactual oxidation problems during the procedures of isolation and purification of oxidative DNA products. The biomarker 8-OHdG or 8-oxodG has been a pivotal marker for measuring the effect of endogenous oxidative damage to DNA and as a factor of initiation and promotion of carcinogenesis. The biomarker has been used to estimate the DNA damage in humans after exposure to cancer-causing agents, such as tobacco smoke, asbestos fibers, heavy metals, and polycyclic aromatic hydrocarbons. In recent years, 8-OHdG has been used widely in many studies not only as a biomarker for the measurement of endogenous oxidative DNA damage but also as a risk factor for many diseases including cancer.

Tobacco smoke contains many toxic, carcinogenic and mutagenic chemicals, as well as stable and unstable free radicals and reactive oxygen species (ROS) in the particulate and the gas phase with the potential for biological oxidative damage. Epidemiological evidence established that smoking is one of the most important extrinsic factor of premature morbidity and mortality. The objective of this study was to investigate oxidative and carcinogenic mechanisms of tobacco and synergistic action with other respirable particles in the respiratory system of smokers. Electron Paramagnetic Resonance (EPR) and spin- trapping techniques were used to study stable free radicals in the cigarette tar, and unstable superoxide anion (O2·-) and hydroxyl (HO·) radicals in the smoke Results showed that the semiquinone radical system has the potential for redox recycling and oxidative action. Further, results proved that aqueous cigarette tar (ACT) solutions can generate adducts with DNA nucleobases, particularly the mutagenic 8-hydroxy-2’-deoxyguanosine (a biomarker for carcinogenesis).Also, we observed synergistic effects in the generation of HO·, through the Fenton reaction, with environmental respirable particles (asbestos fibres, coal dust, etc.) and ambient particulate matter (PM), such as PM10, PM2.5 and diesel exhaust particles (DEP). The highest synergistic effects was observed with the asbestos fibres (freshly grounded), PM2.5 and DEP. Finally, we discuss results from our previous study of conventional cellulose acetate filters and “bio-filters” with hemoglobin impregnated activated carbon, which showed that these filters do not substantially alter the free radical content of smoke in the particulate and in the gaseous phase.

Summary The polyphenols and total antioxidant activities of five apple cultivars, grown by organic and conventional agricultural methods in neighbouring farms, were determined and compared. Total polyphenols in the whole fruit and in the peel were determined by the Folin‐Ciocalteu method, and the total antioxidant activity was determined by three established methods, diphenyl picrylhydrazyl (DPPH), azinobis (3‐ethylbenzthiazoline‐6‐sulfonic acid) (ABTS) and ferric reducing/antioxidant power (FRAP). Polyphenolic content for the whole fruit was in the range of 80–196 and for the peel 165–400 (mg Gallic Acid Equivalent (GAE)/100 g fresh weight) for both types of agricultural practices. Antioxidant activities of fruit extracts were also relatively similar and well correlated to their polyphenolic content. High‐performance liquid chromatography (HPLC) analysis of the most important polyphenolics (chlorogenic acid, catechin, epicatechin, procyanidin B1 and B2, cyaniding 3‐galactoside, phloridzin, quercetin 3‐galactoside and quercetin 3‐arabinoside) also showed that concentrations do not differentiate significantly between the organic and conventional apples. Statistical significance of differences in antioxidant activities among the same cultivars was relatively small (flesh + peel or peel only) for both types of apples. These results indicate that organic apples do not present higher antioxidant or nutritional value compared with conventionally grown ones, as far as polyphenolic content and total antioxidant activities are concerned.

Polycyclic aromatic hydrocarbons (PAHs) were identified and measured in surface seawater and in the tissues (gills and mantle) of indigenous black mussels, Mytilus galloprovincialis, collected from three coastal sites of Saronikos Gulf (Greece), a gulf that exhibits high levels of pollution. The total PAHs measured by spectrofluorometry in the surface seawater were found in the range of 425–459ngL−1 at the most polluted sites 1 and 2 (Elefsis Bay–Salamis Island) and in the range of 103–124ngL−1 at site 3 (Aegina Island). PAHs' sources in seawater were identified by application of specific PAH ratios, such as phenanthrene/anthracene and fluoranthene/pyrene. Levels of PAHs in soft tissues (gills and mantle) of indigenous mussels were much higher than those reported for seawater. Total PAH concentrations in mantle tissues were in the range of 1300–1800ngg−1dry weight (dw) tissue at sites 1 and 2 and approximately 380ngg−1dw at site 3. In gill tissues total PAH concentrations were in the range of 1480–2400ngg−1dw at sites 1 and 2 and approximately 430ngg−1dw at site 3. PAHs composition was dominated by two-, three- and four-ring compounds in seawater, where 17 different PAH compounds were identified and measured in mussel tissues. Mussels can be used as sentinel organisms to monitoring PAHs' contamination, since they concentrate PAHs from the surrounding water media and therefore making the chemical analysis simpler and less prone to error than that for water. In surface seawater possible weathering and photodegradation due to hot climates contribute to reduced PAHs concentrations.

Air pollution has been considered a hazard to human health. In the past decades, many studies highlighted the role of ambient airborne particulate matter (PM) as an important environmental pollutant for many different cardiopulmonary diseases and lung cancer. Numerous epidemiological studies in the past 30 years found a strong exposure-response relationship between PM for short-term effects (premature mortality, hospital admissions) and long-term or cumulative health effects (morbidity, lung cancer, cardiovascular and cardiopulmonary diseases, etc). Current research on airborne particle-induced health effects investigates the critical characteristics of particulate matter that determine their biological effects. Several independent groups of investigators have shown that the size of the airborne particles and their surface area determine the potential to elicit inflammatory injury, oxidative damage, and other biological effects. These effects are stronger for fine and ultrafine particles because they can penetrate deeper into the airways of the respiratory tract and can reach the alveoli in which 50% are retained in the lung parenchyma. Composition of the PM varies greatly and depends on many factors. The major components of PM are transition metals, ions (sulfate, nitrate), organic compound, quinoid stable radicals of carbonaceous material, minerals, reactive gases, and materials of biologic origin. Results from toxicological research have shown that PM have several mechanisms of adverse cellular effects, such as cytotoxicity through oxidative stress mechanisms, oxygen-free radical-generating activity, DNA oxidative damage, mutagenicity, and stimulation of proinflammatory factors. In this review, the results of the most recent epidemiological and toxicological studies are summarized. In general, the evaluation of most of these studies shows that the smaller the size of PM the higher the toxicity through mechanisms of oxidative stress and inflammation. Some studies showed that the extractable organic compounds (a variety of chemicals with mutagenic and cytotoxic properties) contribute to various mechanisms of cytotoxicity; in addition, the water-soluble faction (mainly transition metals with redox potential) play an important role in the initiation of oxidative DNA damage and membrane lipid peroxidation. Associations between chemical compositions and particle toxicity tend to be stronger for the fine and ultrafine PM size fractions. Vehicular exhaust particles are found to be most responsible for small-sized airborne PM air pollution in urban areas. With these aspects in mind, future research should aim at establishing a cleared picture of the cytotoxic and carcinogenic mechanisms of PM in the lungs, as well as mechanisms of formation during internal engine combustion processes and other sources of airborne fine particles of air pollution.

The production and use of polymeric materials worldwide has reached levels of 150 million tonnes per year, and the majority of plastic materials are discarded in waste landfills where are burned generating toxic emissions. In the present study we conducted laboratory experiments for batch combustion/burning of commercial polymeric materials, simulating conditions of open fire combustion, with the purpose to analyze their emissions for chemical characteristics of toxicological importance. We used common types of plastic materials: poly(vinyl chloride) (PVC), low and high density poly(ethylene) (LDPE, HDPE), poly(styrene) (PS), poly(propylene) (PP) and poly(ethylene terephthalate) (PET). Samples of particulate smoke (soot) collected on filters and residue solid ash produced by controlled burning conditions at 600-750 degrees C are used for analysis. Emissions of particulate matter, persistent free radicals embedded in the carbonaceous polymeric matrix, heavy metals, other elements and PAHs were determined in both types of samples. Results showed that all plastics burned easily generating charred residue solid ash and black airborne particulate smoke. Persistent carbon- and oxygen-centered radicals, known for their toxic effects in inhalable airborne particles, were detected in both particulate smoke emissions and residue solid ash. Concentrations of heavy metals and other elements (determined by Inductively Coupled Plasma Emission Spectrometry, ICP, method) were measured in the airborne soot and residue ash. Toxic heavy metals, such as Pb, Zn, Cr, Ni, and Cd were relatively at were found at low concentrations. High concentrations were found for some lithophilic elements, such as Na, Ca, Mg, Si and Al in particulate soot and residue solid ash. Measurements of PAHs showed that low molecular weight PAHs were at higher concentrations in the airborne particulate soot than in the residue solid ash for all types of plastic. Higher-ringed PAHs were detected at higher concentrations in the residue solid ash of PVC as compared to those from the other types of plastic. The open-air burning of plastic material and their toxic emissions is of growing concern in areas of municipal solid waste where open-fires occur intentionally or accidentally. Another problem is building fires in which victims may suffer severe smoke inhalation from burning plastic materials in homes and in working places.