Atmospheric concentrations of organic pollutants in the Arctic between 1993-2006

Continuous and comparable atmospheric monitoring programs to study the transport and occurrence of persistent organic pollutants (POPs) in the atmosphere of remote regions is essential to better understand the global movement of these chemicals and to evaluate the effectiveness of international control measures. Key results from four main Arctic research stations, Alert (Canada), Pallas (Finland), Storhofdi (Iceland) and Zeppelin (Svalbard/Norway), where long-term monitoring have been carried out since the early 1990s, are summarized. We have also included a discussion of main results from various Arctic satellite stations in Canada, Russia, US (Alaska) and Greenland which have been operational for shorter time periods. Using the Digital Filtration temporal trend development technique, it was found that while some POPs showed more or less consistent declines during the 1990s, this reduction is less apparent in recent years at some sites. In contrast, polybrominated diphenyl ethers (PBDEs) were still found to be increasing by 2005 at Alert with doubling times of 3.5 years in the case of deca-BDE. Levels and patterns of most POPs in Arctic air are also showing spatial variability, which is typically explained by differences in proximity to suspected key source regions and long-range atmospheric transport potentials. Furthermore, increase in worldwide usage of certain pesticides, e.g. chlorothalonil and quintozene, which are contaminated with hexachlorobenzene (HCB), may result in an increase in Arctic air concentration of HCB. The results combined also indicate that both temporal and spatial patterns of POPs in Arctic air may be affected by various processes driven by climate change, such as reduced ice cover, increasing seawater temperatures and an increase in biomass burning in boreal regions as exemplified by the data from the Zeppelin and Alert stations. Further research and continued air monitoring are needed to better understand these processes and its future impact on the Arctic environment.

(Table 1) Concentration of persistent organic pollutants in blood plasma of glaucous gulls (Larus hyperboreus) from Bjørnøya

Unpredictable changes in the environment stimulate the avian hypothalamo-pituitary-adrenal axis to produce corticosterone, which induces behavioural and metabolic changes that enhance survival in the face of adverse environmental conditions. In addition to profound environmental perturbations, such as severe weather conditions and unpredictable food shortages, many Arctic-breeding birds are also confronted with chronic exposure to persistent organic pollutants (POPs), some of which are known to disrupt endocrine processes. This study investigated the adrenocortical function of a top predator in the Arctic marine environment, the glaucous gull (Larus hyperboreus). High concentrations of organochlo-rines, brominated flame retardants and metabolically-derived products in blood plasma of incubating glaucous gulls were associated with high baseline corticosterone concentrations in both sexes and a reduced stress response in males. Contaminant-related changes in corticosterone concentration occurred over and above differences in body condition and seasonal variation. Chronically high corticosterone concentrations and/or a compromised adrenocortical response to stress can have negative effects on the health of an individual. The results of the present study suggest that exposure to POPs may increase the vulnerability of glaucous gulls to environmental stressors and thus could potentially compromise their ability to adapt to the rapidly changing environmental conditions associated with climate change that are currently seen in the Arctic.

(Table 1) Concentrations of persistant organic pollutants in brain and liver of glaucous gulls, Bjørnøya, Svalbard archipelago

Dead and dying glaucous gulls (Larus hyperboreus) were collected on Bjornoya in the Barents Sea in 2003, 2004 and 2005. Autopsies of the seabirds only explained a clear cause of death for three (14%) of the 21 birds. A total of 71% of the birds were emaciated. Liver and brain samples were analysed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ether (PBDEs), hexabromo-cyclododecanes (HBCDs) and mercury (Hg). High levels of OCPs, PCBs, PBDEs and alpha-HBCD were found in liver and brain. Compared to the dead and dying glaucous gulls found 1989, the congeners' composition tended to change toward more persistent compounds in the 2003-2005 samples. The brain levels of OCPs and PCBs did not differ between 1989 and 2003-2005, while the liver levels were significantly lower. The brain/liver ratio for PCB and PBDE significantly decreased with halogenations of the molecule, indicating a clear discrimination of highly halogenated PCBs and PBDEs entering the brain. There was further a clear negative correlation between contaminant concentrations and body condition. The brain levels were not as high as earlier published lethal levels of p,p'-DDE or PCB. However, more recent studies reported a range of sub-lethal OCP- and PCB-related effects in randomly sampled glaucous gulls. An additional elevation of pollutants due to emaciation may increase the stress of the already affected birds. The high brain levels of OCP, PCB and PBDE of present study might therefore have contributed to the death of weakened individuals of glaucous gull.

(Table 1) Concentrations of organic pollutants in soil samples from Adélie penguin (Pygoscelis adeliae) colonies and reference sites, Hop Island, Antarctica

Although long-range atmospheric transport has been described as the predominant mechanism for exposing polar regions to persistent organic pollutants (POPs), recent studies have suggested that bird activity can also contribute substantially to contaminant levels in some environments. However, because the species so far reported have all been migratory, it has not been demonstrated conclusively whether locally elevated contamination represents transport from lower latitudes by the migrating birds or, alternatively, redistribution and concentration of contaminants that were already present in the high-latitude environments. The present study demonstrates, for the first time, that several POPs are present in elevated concentrations in an environment frequented by a non-migratory species (Adelie penguins) that spends its entire life in the Antarctic. Levels of POPs, such as p,p'-DDE, hexachlorobenzene (HCB), chlordanes (CHLs) and polychlorinated biphenyls (PCBs), were 10 to 100-fold higher in soil samples from penguin colonies than from reference areas. This significant difference is likely related to local penguin activity, such as a higher abundance of guano and the presence of bird carcasses. This hypothesis is also supported by a higher percentage of persistent congeners (PCB 99, 118, 138 and 153) in the soil from the colonies compared to the reference areas. This profile of PCB congeners closely matched profiles seen in penguin eggs or penguin blood.

Persistent organic pollutants, d13C and d15N in zooplankton, fish and bird species in Kongsfjorden according to season

Seasonality in biomagnification of persistent organic pollutants (POPs; polychlorinated biphenyls, chlorinated pesticides, and brominated flame retardants) in Arctic marine pelagic food webs was investigated in Kongsfjorden, Svalbard, Norway. Trophic magnification factors (TMFs; average factor change in concentration between two trophic levels) were used to measure food web biomagnification in biota in May, July, and October 2007. Pelagic zooplankton (seven species), fish (five species), and seabirds (two species) were included in the study. For most POP compounds, highest TMFs were found in July and lowest were in May. Seasonally changing TMFs were a result of seasonally changing POP concentrations and the d15N-derived trophic positions of the species included in the food web. These seasonal differences in TMFs were independent of inclusion/exclusion of organisms based on physiology (i.e., warm- versus cold-blooded organisms) in the food web. The higher TMFs in July, when the food web consisted of a higher degree of boreal species, suggest that future warming of the Arctic and increased invasion by boreal species can result in increased food web magnification. Knowledge of the seasonal variation in POP biomagnification is a prerequisite for understanding changes in POP biomagnification caused by climate change.

Urban trees and atmospheric pollutants in big cities: Effects in Madrid

Una investigación sobre la mejora de la contaminación del aire (CA) por medio de arbolado urbano se realizó en Madrid, una ciudad con casi 4 M de habitantes, 2,8 M de vehículos y casi 3 M de árboles de mantenimiento público. La mayoría de los árboles estaban en dos bosques periurbanos. Los 650.000 restantes era pies de alineación y parques. Los taxones estudiados fueron Platanus orientalis (97.205 árboles), Ulmus sp. (70.557), Pinus pinea (49.038), Aesculus hippocastanum (22.266), Cedrus sp. (13.678) y Quercus ilex (1.650), de calles y parques. Muestras foliares se analizaron en diferentes épocas del año, así como datos de contaminación por PM10 de 28 estaciones de medición de la contaminación durante 30 años, y también la intensidad del tráfico (IMD) en 2.660 calles. La acumulación de metales pesados (MP) sobre hojas y dentro de estas se estimó en relación con la CA y del suelo y la IMD del tráfico. La concentración media de Ba, Cd, Cr, Cu, Mn, Ni, Pb y Zn en suelo (materia seca) alcanzó: 489,5, 0,7, 49,4, 60,9, 460,9, 12,8, 155,9 y 190,3 mg kg-1 respectivamente. Los árboles urbanos, particularmente coníferas (debido a la mayor CA en invierno) contribuyen significativamente a mejorar la CA sobre todo en calles con alta IMD. La capacidad de las seis sp. para capturar partículas de polvo en su superficies foliares está relacionada con la IMD del tráfico y se estimó en 16,8 kg/año de MP tóxicos. Pb y Zn resultaron ser buenos marcadores antrópicos en la ciudad en relación con el tráfico, que fue la principal fuente de contaminación en los árboles y suelos de Madrid. Las especies de árboles variaron en función de su capacidad para capturar partículas (dependiendo de las propiedades de sus superficies foliares) y acumular los MP absorbidos de los suelos. Las concentraciones foliares de Pb y Zn estuvieron por encima de los límites establecidos en diferentes sitios de la ciudad. La microlocalización de Zn mediante microscópico mostró la translocación al xilema y floema. Se detectaron puntos de contaminación puntual de Cu and Cr en antiguos polígonos industriales y la distribución espacial de los MP en los suelos de Madrid mostró que en incluso en zonas interiores del El Retiro había ciertos niveles elevados de [Pb] en suelo, tal vez por el emplazamiento la Real Fábrica de Porcelana en la misma zona hace 200 años. Distintas áreas del centro de la ciudad también alcanzaron niveles altos de [Pb] en suelo. Según los resultados, el empleo de una combinación de Pinus pinea con un estrato intermedio de Ulmus sp. y Cedrus sp. puede ser la mejor recomendación como filtro verde eficiente. El efecto del ozono (O3) sobre el arbolado en Madrid fue también objeto de este estudio. A pesar de la reducción de precursores aplicada en muchos países industrializados, O3 sigue siendo la principal causa de CA en el hemisferio norte, con el aumento de [O3] de fondo. Las mayores [O3] se alcanzaron en regiones mediterráneas, donde el efecto sobre la vegetación natural es compensado por el xeromorfismo y la baja conductancia estomática en respuesta los episodios de sequía estival característicos de este clima. Durante una campaña de monitoreo, se identificaron daños abióticos en hojas de encina parecidos a los de O3 que estaban plantadas en una franja de césped con riego del centro de Madrid. Dada la poca evidencia disponible de los síntomas de O3 en frondosas perennifolias, se hizo un estudio que trató de 1) confirman el diagnóstico de daño de O3, 2) investigar el grado de los síntomas en encinas y 3) analizar los factores ambientales que contribuyeron a los daños por O3, en particular en lo relacionado con el riego. Se analizaron los marcadores macro y micromorfológicos de estrés por O3, utilizando las mencionadas encinas a modo de parcela experimental. Los síntomas consistieron en punteado intercostal del haz, que aumentó con la edad. Además de un punteado subyacente, donde las células superiores del mesófilo mostraron reacciones características de daños por O3. Las células próximas a las zonas dañadas, presentaron marcadores adicionales de estrés oxidativo. Estos marcadores morfológicos y micromorfológicos de estrés por O3 fueron similares a otras frondosas caducifolias con daños por O3. Sin embargo, en nuestro caso el punteado fue evidente con AOT40 de 21 ppm•h, asociada a riego. Análisis posteriores mostraron que los árboles con riego aumentaron su conductancia estomática, con aumento de senescencia, manteniéndose sin cambios sus características xeromórficas foliares. Estos hallazgos ponen de relieve el papel primordial de la disponibilidad de agua frente a las características xeromórficas a la hora de manifestarse los síntomas en las células por daños de O3 en encina. ABSTRACT Research about air pollution mitigation by urban trees was conducted in Madrid (Spain), a southern European city with almost 4 M inhabitants, 2.8 M daily vehicles and 3 M trees under public maintenance. Most trees were located in two urban forests, while 650'000 trees along urban streets and in parks. The urban taxa included Platanus orientalis (97'205 trees), Ulmus sp. (70’557), Pinus pinea (49'038), Aesculus hippocastanum (22’266), Cedrus sp. (13'678 and Quercus ilex (1'650) along streets and parks. Leave samples were analysed sequentially in different seasons, PM10 data from 28 air monitoring stations during 30 years and traffic density estimated from 2’660 streets. Heavy metal (HM) accumulation on the leaf surface and within leaves was estimated per tree related to air and soil pollution, and traffic intensity. Mean concentration of Ba, Cd, Cr, Cu, Mn, Ni, Pb and Zn in topsoil samples (dry mass) amounted in Madrid: 489.5, 0.7, 49.4, 60.9, 460.9, 12.8, 155.9 and 190.3 mg kg-1 respectively. Urban trees, particularly conifers (due to higher pollution in winter) contributed significantly to alleviate air pollution especially near to high ADT roads. The capacity of the six urban street trees species to capture air-born dust on the foliage surface as related to traffic intensity was estimated to 16.8 kg of noxious metals from exhausts per year. Pb and Zn pointed to be tracers of anthropic activity in the city with vehicle traffic as the main source of diffuse pollution on trees and soils. Tree species differed by their capacity to capture air-borne dust (by different leaf surface properties) and to allocate HM from soils. Pb and Zn concentrations in the foliage were above limits in different urban sites and microscopic Zn revelation showed translocation in xylem and phloem tissue. Punctual contamination in soils by Cu and Cr was identified in former industrial areas and spatial trace element mapping showed for central Retiro Park certain high values of [Pb] in soils even related to a Royal pottery 200 years ago. Different areas in the city centre also reached high levels [Pb] in soils. According to the results, a combination of Pinus pinea with understorey Ulmus sp. and Cedrus sp. layers can be recommended for the best air filter efficiency. The effects of ozone (O3) on trees in different areas of Madrid were also part of this study. Despite abatement programs of precursors implemented in many industrialized countries, ozone remained the main air pollutant throughout the northern hemisphere with background [O3] increasing. Some of the highest ozone concentrations were measured in regions with a Mediterranean climate but the effect on the natural vegetation is alleviated by low stomatal uptake and frequent leaf xeromorphy in response to summer drought episodes characteristic of this climate. During a bioindication survey, abiotic O3-like injury was identified in foliage. Trees were growing on an irrigated lawn strip in the centre of Madrid. Given the little structural evidence available for O3 symptoms in broadleaved evergreen species, a study was undertaken in 2007 with the following objectives 1) confirm the diagnosis, 2) investigate the extent of symptoms in holm oaks growing in Madrid and 3) analyse the environmental factors contributing to O3 injury, particularly, the site water supply. Therefore, macro- and micromorphological markers of O3 stress were analysed, using the aforementioned lawn strip as an intensive study site. Symptoms consisted of adaxial and intercostal stippling increasing with leaf age. Underlying stippling, cells in the upper mesophyll showed HR-like reactions typical of ozone stress. The surrounding cells showed further oxidative stress markers. These morphological and micromorphological markers of ozone stress were similar to those recorded in deciduous broadleaved species. However, stippling became obvious already at an AOT40 of 21 ppm•h and was primarily found at irrigated sites. Subsequent analyses showed that irrigated trees had their stomatal conductance increased and leaf life-span reduced whereas their leaf xeromorphy remained unchanged. These findings suggest a central role of water availability versus leaf xeromorphy for ozone symptom expression by cell injury in holm oak.

Proceedings of the third USA-USSR symposium on the effects of pollutants upon aquatic ecosystems.

3rd.

Proceedings of the third USA-USSR symposium on the effects of pollutants upon aquatic ecosystems.

1st & 2nd

In Situ Bioremediation Methods for Petroleum Pollutants in Soil: A Training Manual for Construction Companies

Construction companies are interested in adopting environmental methods, such as in situ bioremediation, when conducting remediation at petroleum contaminated sites. This interest is due to both the cost benefits associated with in situ bioremediation methods and the environmental movement. This project creates a comprehensive manual comprised of information about site investigations, treatability studies, design, and implementation of in situ bioremediation at petroleum contaminated sites. The training manual also provides information about regulatory requirements and permitting for petroleum contaminated sites.

Effect of the metal in the production of pollutants during the decomposition of two types of electric wires

Support for this work was provided by the Generalitat Valenciana (Spain) with projects PROMETEO/2009/043/FEDER, and by the Spanish MCT CTQ2008-05520.

Formation of brominated pollutants during the pyrolysis and combustion of tetrabromobisphenol A at different temperatures

Tetrabromobisphenol A (TBBPA) is the most widely used brominated flame retardant worldwide. A detailed examination of the degradation products emitted during thermal decomposition of TBBPA is presented in the study. Runs were performed in a laboratory furnace at different temperatures (650 and 800 °C) and in different atmospheres (nitrogen and air). More than one hundred semivolatile compounds have been identified by GC/MS, with special interest in brominated ones. Presence of HBr and brominated light hydrocarbons increased with temperature and in the presence of oxygen. Maximum formation of PAHs is observed at pyrolytic condition at the higher temperature. High levels of 2,4-, 2,6- and 2,4,6- bromophenols were found. The levels of polybrominated dibenzo-p-dioxins and furans have been detected in the ppm range. The most abundant isomers are 2,4,6,8-TeBDF in pyrolysis and 1,2,3,7,8-PeBDF in combustion. These results should be considered in the assessment of thermal treatment of materials containing brominated flame retardants.

Decomposition of two types of electric wires considering the effect of the metal in the production of pollutants

Combustion runs at 700 °C in a horizontal laboratory furnace were carried out on two different electric wires (PVC and halogen-free wire). Tests were performed in the presence and in the absence of the metal conductor of the wires. The analyses of the polycyclic aromatic hydrocarbons (PAHs), chlorobenzenes (CBzs), chlorophenols (CPhs), mono- to octa-chlorodibenzo-p-dioxin and dibenzofurans (PCDD/Fs), and dioxin-like PCBs are shown. Regarding semivolatile compounds, PAHs production decreases in the presence of metal, while a higher amount of chlorinated compounds are emitted. Respect to the PCDD/Fs, the PVC wire in the presence of metal presents the highest emission, with a much more emission of furans than dioxins. The maximum emission is with 2 or 3 chlorine atom PCDD/Fs. PCBs emission correlates with PCDD/F production and represents 3–4% of total toxicity, determined by using WHO2005 factors.

Analysis of pollutants evolved from combustion and pyrolysis of flexible polyurethane foam in a laboratory furnace

Resumen del póster presentado en PIC2015 – the 14th International Congress on Combustion By-Products and Their Health Effects, Umeå, Sweden, 14-17 June 2015.