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Chemical production has continued to in-crease and change since 2003. The potential geographic impact of the chemical industry continued to change from the Atlantic Ocean to the Pacific Ocean, where almost 70 per cent of the industry is expected to operate by 2030, while new products are continually being devel-oped, thus adding to the mixture of chemicals to which biota in the ocean is being exposed.Different lists of hazardous substances have been identified by international organizations, although there is still no agreed single global list of substances that are of concern. The present chapter contains an assessment of the changes since the first Assessment in wa-ter and airborne inputs to the marine environ-ment from land (including groundwater), ships and offshore installations. In addition, the information in the present chapter builds upon the assessment of the list of hazardous sub-stances used in the first Assessment, namely, POPs, metals, hydrocarbons and radioactive substances. It includes new information on rare earth elements, PPCPs and airborne in-puts of nitrogen oxides and sulfur oxides that were not included in the first Assessment.

Zur Stoffgruppe der mehr als 4.700 per-und polyfluorierten Alkylsubstanzen (PFAS) gehören neben den gut untersuchten und bereits regulierten langkettigen PFAS auch Ersatzstoffe und weitere PFAS, die bislang nicht im Fokus standen. Um dieseSubstanzen im Rheinverlauf zu untersuchen, wurden 29 PFAS in Oberflächenwasser und Sedimenten analysiert. In 50% bzw. 42% der Wasserproben wurde der etherbasierte Er-satzstoff Hexafluorpropylenoxid-Dimersäure (HFPO-DA) und die cyclische Substanz Perfluor-4-ethylcyclohexansulfonsäure (PFECHS) nachgewiesen. Die Konzentration der bislang wenig untersuchten Perfluoralkylphosphinsäure 6:8 PFPiA in den Sedimentproben war vergleichbar mit den Konzentrationen langkettiger PFAS, die 78 ± 8 % der PFAS-Summe aus-machten. Das stellt die Rolle der Sedimente als Senke für langkettige PFAS heraus

An international sampling campaign was carried out to comprehensively investigate the occurrence of polycyclic aromatic hydrocarbons (PAHs) in the marine sediments from the European Baltic and North Seas, Chinese Bohai and Yellow Seas. The concentrations of ∑18PAHs in the samples from these four seas were in the range of 0.91–5361 ng/g dry weight (dw), 0.46–227 ng/g dw, 25.0–308 ng/g dw and 4.3–659 ng/g dw, respectively. 4-rings PAHs, e.g., fluoranthene, pyrene and benzo(b)fluoranthene, were commonly the dominant compounds in all the samples. The PAH sources were identified via composition patterns, diagnostic ratios, principal component analysis (PCA) and positive matrix factorization (PMF). Coal combustion, vehicular emission, coke plant and petroleum residue were apportioned as the main sources in these marine sediments. However, through PMF modeling, different contributions of these sources were quantified to the deposited PAHs in the seas, suggesting distinct anthropogenic impacts on the adjacent marine system. It is note-worthy that biomass combustion may not be the main source of PAHs in the majority of sediments from these seas. This was evidenced by the ratios of naphthalene against its methylated derivatives (i.e. 1-,2-methylnaphthalenes) other than the composition pattern in the samples, of which the approach is in prospect of developing in future studies.

The atmospheric deposition of mercury (Hg) occurs via several mechanisms, including dry and wet scavenging by precipitation events. In an effort to understand the atmospheric cycling and seasonal depositional characteristics of Hg, wet deposition samples were collected for approximately 5 years at 17 selected GMOS monitoring sites located in the Northern and Southern hemispheres in the framework of the Global Mercury Observation System (GMOS) project. Total mercury (THg) exhibited annual and seasonal patterns in Hg wet deposition samples. Interannual differences in total wet deposition are mostly linked with precipitation volume, with the greatest deposition flux occurring in the wettest years. This data set provides a new insight into baseline concentrations of THg concentrations in precipitation worldwide, particularly in regions such as the Southern Hemisphere and tropical areas where wet deposition as well as atmospheric Hg species were not investigated before, opening the way for future and additional simultaneous measurements across the GMOS network as well as new findings in future modeling studies.

The Chagos Archipelago was designated a no-take marine protected area (MPA) in 2010; it covers 550 000km2, with more than 60 000km2 shallow limestone platform and reefs. This has doubled the global cover of such MPAs. It contains 25-50% of the Indian Ocean reef area remaining in excellent condition, as well as the world's largest contiguous undamaged reef area. It has suffered from warming episodes, but after the most severe mortality event of 1998, coral cover was restored after 10years. Coral reef fishes are orders of magnitude more abundant than in other Indian Ocean locations, regardless of whether the latter are fished or protected. Coral diseases are extremely low, and no invasive marine species are known. Genetically, Chagos marine species are part of the Western Indian Ocean, and Chagos serves as a 'stepping-stone' in the ocean. The no-take MPA extends to the 200nm boundary, and. includes 86 unfished seamounts and 243 deep knolls as well as encompassing important pelagic species. On the larger islands, native plants, coconut crabs, bird and turtle colonies were largely destroyed in plantation times, but several smaller islands are in relatively undamaged state. There are now 10 'important bird areas', coconut crab density is high and numbers of green and hawksbill turtles are recovering. Diego Garcia atoll contains a military facility; this atoll contains one Ramsar site and several 'strict nature reserves'. Pollutant monitoring shows it to be the least polluted inhabited atoll in the world. Today, strict environmental regulations are enforced. Shoreline erosion is significant in many places. Its economic cost in the inhabited part of Diego Garcia is very high, but all islands are vulnerable. Chagos is ideally situated for several monitoring programmes, and use is increasingly being made of the archipelago for this purpose. © 2012 John Wiley and Sons, Ltd.

We analyze 1977-2010 trends in atmospheric mercury (Hg) from 21 ship cruises over the North Atlantic (NA) and 15 over the South Atlantic (SA). We find a steep 1990-2009 decline of -0.046±0.010 ngm-3 a -1 (-2.5% a-1) over the NA (steeper than at Northern Hemispheric land sites) but no significant decline over the SA. Surface water Hg0 measurements in the NA show a decline of -5.7% a-1 since 1999, and limited subsurface ocean data show an ∼80% decline from 1980 to present. We use a coupled global atmosphere-ocean model to show that the decline in NA atmospheric concentrations can be explained by decreasing oceanic evasion from the NA driven by declining subsurface water Hg concentrations. We speculate that this large historical decline of Hg in the NA Ocean could have been caused by decreasing Hg inputs from rivers and wastewater and by changes in the oxidant chemistry of the atmospheric marine boundary layer. © 2012. American Geophysical Union. All Rights Reserved.

The El Niño–Southern Oscillation (ENSO) affects the tropospheric concentrations of many trace gases. Here we investigate the ENSO influence on mercury concentrations measured in the upper troposphere during Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrumented Container flights and at ground at Cape Point, South Africa, and Mace Head, Ireland. Mercury concentrations cross-correlate with Southern Oscillation Index (SOI) with a lag of 8 ± 2 months. Highest mercury concentrations are always found at the most negative SOI values, i.e., 8 months after El Niño, and the amplitude of the interannual variations fluctuates between ~5 and 18%. The time lag is similar to that of CO whose interannual variations are driven largely by emissions from biomass burning (BB). The amplitude of the interannual variability of tropospheric mercury concentrations is consistent with the estimated variations in mercury emissions from BB. We thus conclude that BB is a major factor driving the interannual variation of tropospheric mercury concentrations.

Atmospheric chemistry and transport of mercury play a key role in the global mercury cycle. However, there are still considerable knowledge gaps concerning the fate of mercury in the atmosphere. This is the second part of a model intercomparison study investigating the impact of atmospheric chemistry and emissions on mercury in the atmosphere. While the first study focused on ground-based observations of mercury concentration and deposition, here we investigate the vertical and interhemispheric distribution and speciation of mercury from the planetary boundary layer to the lower stratosphere. So far, there have been few model studies investigating the vertical distribution of mercury, mostly focusing on single aircraft campaigns. Here, we present a first comprehensive analysis based on various aircraft observations in Europe, North America, and on intercontinental flights. The investigated models proved to be able to reproduce the distribution of total and elemental mercury concentrations in the troposphere including interhemispheric trends. One key aspect of the study is the investigation of mercury oxidation in the troposphere. We found that different chemistry schemes were better at reproducing observed oxidized mercury patterns depending on altitude. High concentrations of oxidized mercury in the upper troposphere could be reproduced with oxidation by bromine while elevated concentrations in the lower troposphere were better reproduced by OH and ozone chemistry. However, the results were not always conclusive as the physical and chemical parameterizations in the chemistry transport models also proved to have a substantial impact on model results.

The ash cloud of the Eyjafjallajökull (also referred to as: Eyjafjalla (e.g. Schumann et al., 2011), Eyjafjöll or Eyjafjoll (e.g. Ansmann et al., 2010)) volcano on Iceland caused closure of large parts of European airspace in April and May 2010. For the validation and improvement of the European volcanic ash forecast models several research flights were performed. Also the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) flying laboratory, which routinely measures at cruise altitude (≈11 km) performed three dedicated measurements flights through sections of the ash plume. Although the focus of these flights was on the detection and quantification of the volcanic ash, we report here on sulphur dioxide (SO2) and bromine monoxide (BrO) measurements with the CARIBIC DOAS (Differential Optical Absorption Spectroscopy) instrument during the second of these special flights on 16 May 2010. As the BrO and the SO2 observations coincide, we assume the BrO to have been formed inside the volcanic plume. Average SO2 and BrO mixing ratios of ≈40 ppb and ≈5 ppt respectively are retrieved inside the plume. The BrO to SO2 ratio retrieved from the CARIBIC observation is ≈1.3×10−4. Both SO2 and BrO observations agree well with simultaneous satellite (GOME-2) observations. SO2 column densities retrieved from satellite observations are often used as an indicator for volcanic ash. As the CARIBIC O4 column densities changed rapidly during the plume observation, we conclude that the aerosol and the SO2 plume are collocated. For SO2 some additional information on the local distribution can be derived from a comparison of forward and back scan GOME-2 data. More details on the local plume size and position are retrieved by combining CARIBIC and GOME-2 data.

The knowledge of the vertical distribution of atmospheric mercury (Hg) plays an important role in determining the transport and cycling of mercury. However, measurements of the vertical distribution are rare, because airborne measurements are expensive and labour intensive. Consequently, only a few vertical Hg profile measurements have been reported since the 1970s. Besides the Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container (CARIBIC) observations, the latest vertical profile over Europe was measured in 1996. Within the Global Mercury Observation System (GMOS) project, four vertical profiles were taken on board research aircraft (CASA-212) in August 2013 in background air over different locations in Slovenia and Germany. Each vertical profile consists of at least seven 5 min horizontal flight sections from 500 m above ground to 3000 m a.s.l. Gaseous elemental mercury (GEM) and total gaseous mercury (TGM) were measured with Tekran 2537X and Tekran 2537B analysers. In addition to the mercury measurements, SO2, CO, O3, NO, and NO2, basic meteorological parameters (pressure, temperature, relative humidity) have been measured. Additional ground-based mercury measurements at the GMOS master site in Waldhof, Germany and measurements onboard the CARIBIC passenger aircraft were used to extend the profile to the ground and upper troposphere respectively. No vertical gradient was found inside the well-mixed boundary layer (variation of less than 0.1 ng m−3) at different sites, with GEM varying from location to location between 1.4 and 1.6 ng m−3 (standard temperature and pressure, STP: T = 273.15 K, p = 1013.25 hPa). At all locations GEM dropped to 1.3 ng m−3 (STP) when entering the free troposphere and remained constant at higher altitudes. The combination of the vertical profile, measured on 21 August 2013 over Leipzig, Germany, with the CARIBIC measurements during ascent and descent to Frankfurt Airport, Germany, taken at approximately the same time, provide a unique central European vertical profile from inside the boundary layer (550 m a.s.l) to the upper free troposphere (10 500 m a.s.l.) and show a fairly constant free-tropospheric TGM concentration of 1.3 ng m−3 (STP).

Spatial distributions of perfluoroalkyl substances (PFASs) were investigated in surface waters in Shanghai, Jiangsu and Zhejiang Provinces of eastern China during 2011. A total of 39 samples of surface waters, including 29 rivers, 6 lakes and 4 reservoirs were collected. High performance liquid chromatography/negative electrospray ionization-tandem mass spectrometry (HPLC/(−)ESI-MS/MS) was used to identify and quantify PFASs. Concentrations of PFAS were greater in Shanghai than that in Zhejiang Province. Concentrations of the sum of PFASs (∑PFASs) in Shanghai and Kunshan ranged from 39 to 212 ng L−1, while in Zhejiang Province, concentrations of ∑PFASs ranged from 0.68 to 146 ng L−1. Perfluorooctanoic acid (PFOA) was the prevalent PFAS in Shanghai. In contrast, PFOA and perfluorohexanoic acid (PFHxA) were the prevalent PFASs in Zhejiang Province. Concentrations of perfluorooctane sulfonate (PFOS) ranged from

The Chagos Archipelago was designated a no-take marine protected area (MPA) in 2010; it covers 550 000km2, with more than 60 000km2 shallow limestone platform and reefs. This has doubled the global cover of such MPAs. It contains 25-50% of the Indian Ocean reef area remaining in excellent condition, as well as the world's largest contiguous undamaged reef area. It has suffered from warming episodes, but after the most severe mortality event of 1998, coral cover was restored after 10years. Coral reef fishes are orders of magnitude more abundant than in other Indian Ocean locations, regardless of whether the latter are fished or protected. Coral diseases are extremely low, and no invasive marine species are known. Genetically, Chagos marine species are part of the Western Indian Ocean, and Chagos serves as a 'stepping-stone' in the ocean. The no-take MPA extends to the 200nm boundary, and. includes 86 unfished seamounts and 243 deep knolls as well as encompassing important pelagic species. On the larger islands, native plants, coconut crabs, bird and turtle colonies were largely destroyed in plantation times, but several smaller islands are in relatively undamaged state. There are now 10 'important bird areas', coconut crab density is high and numbers of green and hawksbill turtles are recovering. Diego Garcia atoll contains a military facility; this atoll contains one Ramsar site and several 'strict nature reserves'. Pollutant monitoring shows it to be the least polluted inhabited atoll in the world. Today, strict environmental regulations are enforced. Shoreline erosion is significant in many places. Its economic cost in the inhabited part of Diego Garcia is very high, but all islands are vulnerable. Chagos is ideally situated for several monitoring programmes, and use is increasingly being made of the archipelago for this purpose. © 2012 John Wiley and Sons, Ltd.

Consumption of pesticides in China has increased rapidly in recent years; however, occurrence and fate of current-use pesticides (CUPs) in China coastal waters are poorly understood. Globally banned pesticides, so-called historic-use pesticides (HUPs), are still commonly observed in the environment. In this work, air and surface seawater samples taken from the Bohai and Yellow Seas in May 2012 were analyzed for CUPs including trifluralin, quintozene, chlorothalonil, dicofol, chlorpyrifos, and dacthal, as well as HUPs (hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), and endosulfan). CUP profile in both air and seawater samples generally reflected their consumption patterns in China. HUPs in the air and seawater samples were in comparable levels as those of CUPs with high concentrations. α-Endosulfan, dicofol, and chlorothalonil showed strong net deposition likely resulting from their intensive use in recent years, while CUPs with low consumption amount (quintozene and dacthal) were close to equilibrium at most samplings sites. Another CUP with high usage amout (i.e., chlorpyrifos) underwent volatilization possibly due to its longer half-life in seawater than that in air. α-HCH and γ-HCH were close to equilibrium in the Bohai Sea, but mainly underwent net deposition in the Yellow Sea. The net deposition of α-HCH could be attributed to polluted air pulses from the East China identified by air mass back trajectories. β-HCH showed net volatilization in the Bohai Sea, which was driven by its relative enrichment in seawater. HCB either slightly favored net volatilization or was close to equilibrium in the Bohai and Yellow Seas.

Die Polregionen gelten als letzte großflächige Reinraumgebiete unserer Erde. Mit den Methoden der modernen chemischen und physikalischen Analytik lassen sich jedoch auch in der Arktis und, in geringerem Ausmaß in der Antarktis, chemische Elemente und Verbindungen nachweisen, die erst durch den Menschen verstärkt in die Umwelt eingetragen wurden. Diese Spurenstoffe lassen sich dort üblicherweise in ihrer sogenannten »Hintergrundkonzentration«, d.h. in einer Art globalen Grundbelastung nachweisen, die für einige Umweltschadstoffe seit Beginn der Industrialisierung ansteigt. Aufgrund der niedrigen Temperaturen an den Polen werden mittelflüchtige Substanzen aus den industrialisierten und wärmeren Gebieten der Erde über die Atmosphäre in Richtung Nord- und Südpol transportiert und kondensieren dort aus (»Kaltphasenanreicherung« oder auch »global distillation«). Ozeanische Transporte von Schadstoffen in die Polregionen werden über die globalen Strömungsmuster gesteuert. Die wesentlichen Transportpfade, auf die in diesem Kapitel im einzelnen eingegangen wird, sind für die Arktis in Abb. 5.3-1 dargestellt. Auf unterschiedlichen Klimaszenarien beruhende Untersuchungen zeigen, dass signifikante Veränderungen der wesentlichen atmosphärischen und ozeanischen Transportmuster möglich sind. Dies bedeutet auch, dass die Klimavariabilität der vergangenen Dekaden möglicherweise für einige der beobachteten Trends der Schadstoffbelastung zum Teil mitverantwortlich sein könnte.

The aim of this chapter is to provide an up-to-date overview of the major processes and mechanisms affecting the dynamics of mercury in the atmosphere and at the interfaces with other ecosystems. Understanding of Hg transformations in the atmosphere and major removal processes are dealt with in Section 3.2. Sections 3.3, 3.4 and 3.5 detail the measurements that have been made and compile the available information. The results of current modelling efforts towards an understanding of atmospheric processes at regional and global scales are detailed in Sections 3.6 and 3.7. The chapter concludes with a list of new findings on atmospheric pathways, transport and fate and an overview of research gaps and areas for future studies.

A unique set of gaseous mercury measurements in the upper troposphere and lower stratosphere (UT/LS) has been obtained during the monthly CARIBIC (www. caribic-atmospheric. com) flights since May 2005. The passenger Airbus 340-600 of Lufthansa covered routes to the Far East, North America, India, and the southern hemisphere. The accompanying measurements of CO, O-3, NOy, H2O, aerosols, halocarbons, hydrocarbons, greenhouse gases, and several other parameters as well as backward trajectories enable a detailed analysis of these measurements. Speciation tests have shown that the CARIBIC measurements represent a good approximation of total gaseous mercury (TGM) concentrations. Above the tropopause TGM always decrease with increasing potential vorticity (PV) and O-3 which implies its conversion to particle bound mercury. The observation of the lowest TGM concentrations at the highest particle concentrations in the stratosphere provides further evidence for such conversion. We will show how a seasonally dependent conversion rate could be derived using concomitantly measured SF6 mixing ratios as a timer. Tropospheric mercury data suggest the existence of a decreasing trend in the northern hemisphere whose size is comparable with the trend derived from long- term measurements by ship cruises, at Cape Point (South Africa) and Mace Head (Ireland).

Eighteen polycyclic aromatic hydrocarbons (PAHs) were simultaneously measured in surface seawater and boundary layer air from the North Pacific toward the Arctic Ocean during the Fourth Chinese National Arctic Research Expedition in the summer of 2010. Atmospheric Σ18PAH ranged from 910 to 7400 pg m−3, with the highest concentrations observed in the coastal regions of East Asia. Correlations of PAHs\' partial pressures versus inverse temperature were not significant, indicating the importance of ongoing primary sources on ambient PAH levels in the remote marine atmosphere. The relatively high atmospheric concentrations observed in the most northerly latitudes of the Arctic Ocean suggest the influence of regional sources. For example, higher levels of particle‐bound PAHs were observed in the air of the Arctic Ocean than the North Pacific, indicating forest fire and/or within‐Arctic sources. Concentrations of PAHs in surface seawater were within a range of 14–760 pg L−1 and generally decreased with increasing latitude. The observed air‐sea gas exchange gradients strongly favored net deposition of PAHs along the entire cruise, with increasing deposition with increasing latitude, while the particle‐bound dry deposition fluxes (particularly for the high molecular weight PAH) were highest at sample sites close to East Asia. Based on characteristic PAH ratios, atmospheric PAHs originated from the combustion of biomass or coal, while the ratios observed in seawater reflected a mixture of sources. Given the dominance of primary emissions to the atmosphere and the relatively fast removal of PAHs from the water column, then PAHs will continue to load into the surface waters of the remote marine environment via atmospheric deposition.