Recently polyfluoroalkyl compounds (PFCs) were discovered as emerging persistentorganic pollutants. Because of their unique physicochemical properties due to theircombination of lipophilic and hydrophilic characteristics, PFCs have been widely used inmany consumer products, such as polymerisation aids, stain repellents on carpets, textiles, andpaper products for over 50 years. From the production and use of these products, PFCs can bereleased into the environment. Scientific concern about PFCs increased due to their globaldistribution and ubiquitous detection in the environment, especially in marine mammals.An analytical protocol was developed for the analysis of PFCs in water samples andvarious biological matrices. The samples were analysed for 40 PFCs plus 20 isotope-labelledinternal standards using high performance liquid chromatography/negative electrosprayionisation-tandem mass spectrometry (HPLC/(-)ESI-MS/MS). Furthermore, the analyticalquality of the laboratory has been approved in interlaboratory studies.In the first part of this Ph.D. thesis was investigated the occurrence, distribution patternand transportation mechanisms of PFCs in seawater. The rivers had a high influence on thedistribution of PFCs in offshore surface water in the German Bight, with decreasingconcentrations with increasing distance from the coast (see publication I). The research onthe spatial distribution of PFCs in coastal area is very important for the understanding of thetransportation and fate of PFCs in the marine environment. Furthermore, the longitudinal andlatitudinal distribution of PFCs in surface water of the Atlantic Ocean was investigated (seepublication II). The results indicate that trans-Atlantic Ocean currents caused the decreasingconcentration gradient from the Bay of Biscay to the South Atlantic Ocean and theconcentration drop-off close to the Labrador Sea. These data are very useful for globaltransportation models, in which industrial areas are considered as sources, and ocean watersas sinks of PFCs.The second part of this Ph.D. thesis examined the mechanisms and pathways of PFCs inharbor seals (Phoca vitulina) and their temporal trends in the German Bight. Firstly, thewhole body burden of PFCs and their tissue distribution (i.e., liver, kidney, lung, heart, blood,brain, muscle, thyroid, thymus, and blubber) was investigated in harbor seals (seepublication III). This study is relevant for calculation of the bioaccumulation potential ofthese compounds in marine mammals. Secondly, the temporal trends over the last decade andassociations between PFC concentration and the evidence of diseases, spatial distribution, ageand sex were evaluated in archived harbor seal livers (see publication IV). The results showsignificant declining concentrations of many PFCs indicating the replacement of these PFCsby shorter chained and less bioaccumulative compounds.Several studies were performed besides the main issue of the Ph.D. work. Firstly, watersamples were collected along the river Elbe into the North Sea to examine the distribution ofPFCs in the dissolved and particulate phase, their discharge into the North Sea, and theinfluence of waste water treatment plant effluents to the riverine mass flow. Furthermore,surface water samples were collected in the North Sea, Baltic Sea and Norwegian Sea, wherethe occurrence and spatial distribution between river estuaries, coastal waters, in brackish aswell as salt water, and open sea water were compared. Finally, within the frame of a researchstay at the National Institute of Advanced Industrial Science and Technology (AIST) in Japan,the partitioning behaviour of PFCs between pore water and sediment in two sediment coresfrom Tokyo Bay was investigated.This Ph.D. thesis has improved our knowledge of the occurrence and distribution of PFCsin water and biota highlighting association between PFCs and pathological conditions,potential sources and sinks, spatial distribution, and changes in their pattern and long-termperspective trends.
Halogenated flame retardants (HFRs) have been applied since the 1960s in various industrial and consumer products to protect humans as well as private and public possessions. In the past decade polybrominated diphenyl ethers (PBDEs), formerly the major applied HFRs were widely restricted and adopted as Persistent Organic Pollutants (POPs) in the Stockholm Convention due to their adverse effects on humans and the environment as well as their ubiquitous occurrence in the global environment. Besides PBDEs, various alternative HFRs have been applied for decades as well, or were recently developed to replace PBDEs. However, their potential adverse properties, environmental distribution and fate are largely unknown. Therefore, this thesis addresses the global occurrence, distribution and transport of alternative HFRs versus PBDEs in the marine atmosphere and seawater toward the Polar Regions in order to examine their longrange atmospheric transport (LRAT) potential. This thesis presents the first data on alternative HFRs in the atmosphere of the marine environment and the Polar Regions. Alternative brominated flame retardants (BFRs), Dechlorane compounds and PBDEs were investigated in high-volume air and seawater samples taken along several sampling transects in the Atlantic Ocean, Pacific Ocean and Indian Ocean toward the Polar Regions of the Arctic and Antarctic. In addition, three sampling cruises were conducted in the German Bight, North Sea. Several alternative HFRs were detected in the global marine atmosphere and seawater with hexabromobenzene (HBB), pentabromotoluene (PBT), pentabromobenzene (PBBz), 2,3- dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and Dechlorane Plus (DP) being the predominant compounds which were observed in concentrations similar or even higher than PBDEs. Total atmospheric concentrations ranged from <1 pg m-3 over the open oceans up to 42 pg m-3 over the East Indian Archipelago. Seawater concentrations ranged from <1 pg L-1 in open ocean seawater up to 21 pg L-1 in coastal regions, while estuarine concentrations reached up to 6800 pg L-1. Overall, the comparison revealed that alternative HFRs dominate versus PBDEs in air and seawater, both in coastal regions as well as the Polar Regions, showing a shift from PBDEs toward alternative HFR in the marine atmosphere and seawater. The distribution in the global atmosphere was strongly influenced by the proximity to potential source regions and the pathway of the sampled air masses. Highest concentrations were observed in continentally influenced air masses, while low background concentrations occurred during sampling of oceanic remote air masses. In general, Western Europe, East and Southeast Asia but also Africa were identified as source regions for the marine environment, especially for alternative HFRs as well as BDE-209. In contrast, relatively low peak concentrations of the PBDE congeners of the Penta- and OctaBDE mixtures under continental influence were observed, indicating limited emissions of legacy PBDEs. The dry air-seawater gas exchange estimation showed that the atmosphere is a source for seawater resulting in net deposition into the global oceans after atmospheric emissions and transport, both in coastal regions as well as in the open oceans. Besides atmospheric depositions, riverine discharge was shown to act as source for coastal environments. The investigation of sampling transects toward the Polar Regions revealed that several alternative HFRs – in particular HBB, PBT, DPTE, PBBz and DP – undergo LRAT toward the Polar Regions in an extent similar to PBDEs and, therefore, meet the LRAT criterion of POPs under the Stockholm Convention. DP was found to undergo LRAT attached to airborne particles whereby stereoselective LRAT differences were shown for the two DP stereoisomers. With respect to LRAT, the results of this thesis therefore imply that alternative HFRs – in particular HBB, PBT, DPTE and DP – aren’t suitable replacements for PBDEs, but chemicals of emerging global environmental concern and possible future POPs.