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Examines organic compounds as contaminants of the Elbe River and its tributaries in Germany. Group of contaminants corresponding either to diffuse or local contamination which can be distinguished; Examples of commonly observable compounds detected with a distribution reflecting the contribution of nonpoint source emissions.

Microplastic particles are found in environmental compartments all over the world and receive a great deal of attention, especially in the aquatic environment. Currently, a particularly high input of microplastics via Asian rivers is assumed, but so far, there are hardly any data through field measurements. Three rivers in South India were considered for this purpose to focus on their microplastic load. The emphasis was on the comparison of microplastic concentrations in urban and rural rivers. While two rivers in the megacity Chennai (Tamil Nadu) were found to have an average microplastic concentration of 0.4 microplastic particles/L, a rural river near Munnar (Kerala) had an average concentration of 0.2 microplastic particles/L. Rough estimates of annual microplastic discharge from the Adyar River (Chennai) into the Bay of Bengal are found to be as high as 11.6 trillion microplastic particles. This study should be one of the first baseline studies for microplastic loads in South Indian streams and should be complemented with further environmental sampling before, during and after the monsoon season to get more detailed information on the storage and transportation of fluvial microplastics under different weather conditions. [ABSTRACT FROM AUTHOR]

Threatened by both far-field and less frequent local tsunami events, the Hawaiian Islands are prone for extreme wave events, such as the 1946 Aleutian, 1952 Kamchatka, 1957 Aleutians or the 1960 Chile tsunami. In the coastal marshland of the Kahana Bay, Oahu, the event layer from the respectively 1946 or 1957 tsunamis additional paleo-tsunami layers can be observed. Dating back to the 12th-14th century these prehistoric event layers have been analyzed using a multi-proxy approach including organic geochemical applications, such as biomarkers. For the biomarker application, samples were extracted in three different ways to obtain the free and bound organic compounds out of the sediments. Free compounds were extracted using a solid-liquid extraction (acetone and n-hexane), whilst bound compounds were extracted twice using first a basic hydrolysis and then pyrolysis. All three extracts were fractionated and analyzed by gas chromatography-mass spectrometry (GC-MS).Several different natural compounds (n>120) were detected, of which most can be affiliated to compound groups, such as n-alkanes, fatty acids (saturated and unsaturated), steroids or carboxylic acids. Results show clear differentiation between sedimentary layers deposited before and following the event. In contrast to these layers is the paleo-tsunami deposit, showing concentration differences as well as a deviant occurrence of biomarkers. However, the occurrence of marine biomarkers remains difficult as the coring sites are located relatively far inland and an inundating wave would erode and incorporate large amounts of terrestrial material on its way inland, leading to a dilution of the marine signal. Still, the organic geochemical signature has been successfully used to characterize and distinguish the paleo-tsunami event layer from predecessing and subsequent depositional environments. [ABSTRACT FROM AUTHOR]

As the largest active terrestrial reservoir of organic carbon (OC), soils play an essential role inthe global carbon cycle. Their response to rising global temperatures is of uttermost interest,having the potential to move and store an extensive amount of carbon within the climatesystem. One of the critical aspects of soil OC is the turnover rate, which has been reported todecrease rapidly below the A horizon. While most studies have focused on processes thatpromote higher ages of organic matter including various stabilization mechanisms, recentobservations suggest that part of the soil OC might already have been deposited with thesediment parent material, i.e. geogenic carbon and thus has turnover rates of millennia orlonger. This could lead to underestimations of turnover rates and needs to be taken intoaccount in biogeochemical models. This study aims to characterize geogenic OC and quantifyits contribution to subsoils. Deep soil cores (10 m) were collected from three different parent materials incentral Germany: Pleistocene loess, Paleogene sand and red sandstone. These wereanalyzed using a set of geochemical methods, including bulk 14C, selected lipidbiomarkers, pyrolysis-GCMS and 13C-CPMAS spectroscopy in order to characterizeorganic matter at multiple depth intervals and identify contributions of geogenicorigin. In the Pleistocene loess, apparent bulk 14C ages increased with depth from 2,200 to30,700 years BP, reflecting the depositional history of this relatively young sediment. Thelipid analysis revealed multiple sections with high OC content and Carbon Preference Index(CPI) values (>13), suggesting the presence of paleosols. The oldest part yielded lower CPIvalues (<3.0), evidently phases where deposition was too rapid for pedologicalprocesses to take place. This was supported by 13C-CPMAS NMR spectroscopy,demonstrating a highly degraded (alkyl-C rich) but soil like chemical composition of theOM. In these sections the organic matter is scarce and characterized by aliphaticcompounds such as n-alkanes, possibly deposited along with the mineral material,and methyl ketones as well as monoaromatic compounds including benzene andtoluene. Apparent bulk 14C ages of the Paleogene sand varied between 6,750 and 12,000 years,significantly younger than the deposition of the sediment (23-34 Mio. years BP). The sampleswere absent of n-alkanes and only small traces of fatty acids (2.67-0.59 μg/g dry weight)were detected, dominated by even long chain homologues. Young ages were also displayedby the red sandstone (about 245 Mio. years old), ranging between 12,760 and 17,400 yearsBP. In summary, the hitherto investigations of the deep sediment cores of differentparent material show a significant variance in age and composition of the OC fordifferent parent material at various depths, owing to OC components deposited alongwith the sediment parent material mixed with more recently deposited biogeniccarbon. [ABSTRACT FROM AUTHOR]

As plastics have been used in an increasing amount within the past century, the resulting pollution of oceans, rivers and terrestrial environments with plastics and increasing amount of microplastics, has been observed. However, the study of microplastic pollution in sedimentary environmental systems is at a preliminary stage to date. This is related to lacking methods displaying unambiguously the pollution of microplastics in sediments in a qualitative and quantitative manner. As not all critical environments are polluted to an extent observed for macro-plastics, knowledge about pollution of these environments also on lower concentration levels is of great interest.We present a new approach analyzing sediments for their microplastic pollution using offline pyrolysis. Six of the polymers (PS, PP, PE, PMMA, PVC, PET) most frequently used in everyday life were selected. For later recovery of these polymers in sediments, first blank samples were treated for analysis. Samples were pyrolyzed in an oxygen-free atmosphere, the pyrolysates were dried over sodium sulfate and fractionated using organic solvents of different polarity. Subsequently, the analyses were performed by gas chromatography-mass spectrometry. The determination of polymer residues was based on the identification of specific pyrolysis products for each polymer to identify and quantify the original polymer pollution. In a second step, polymers were added to extra pure sea sand to simulate natural environments polluted with microplastics. These spiked samples were again treated with the described analytical procedure. Preliminary results show that the detection of the prior characterized pyrolysis products of the six most common polymers is possible also in samples representing natural environments. Further on, an evaluation of the minimum total pollution by microplastics is possible via the detected concentrations in the sediments. However, results show as well that concentrations remain very low adjoining the detection-limit, showing that the analysis of microplastics in natural environments by pyrolysis methods is possible but remains more challenging than the more present macro-plastic pollution. [ABSTRACT FROM AUTHOR]

The Proterozoic black shales of Rohtas Subgroup in Vindhyan basin are analyzed to assess their hydrocarbon generation potential. A total of 50 core samples of shales and limestones were collected from borehole core of Rohtasgarh limestone in Amehta mine, Vindhyan basin located in Katni district, Madhya Pradesh. The petrographic analysis, X-Ray diffraction, rock eval pyrolysis and maceral studies were carried out on separated black shales from the carbonates. The study presents that the Rohtas Subgroup of Semri Group consists of greyish to black limestone, greyish to greyish black shales, calcareous shales, silicified shales, pyritic shales and dark black shales alterations with limestones. XRD study reveals the presence of quartz (23.4%), plagioclase feldspar (21.9%), siderite (10.9%), aragonite (2.93%), calcite(1.9%), hematite (4.23%), illite (1.27%), kaolinite (3.2%), pyrite (3.86%), dolomite (8.2%), chlorite (2.43%), gypsum (4.02%), albite (3.4%), potassium feldspar (1.9%) in the samples, where smectite is dominating clay and feldspar in the form of potassium and plagioclase feldspar is the chief constituent among the detrital framework grains. The total organic content (TOC) of the shale units ranges from 0.22 wt. % to 1.08 wt.%, whereas hydrogen index (HI) ranges from 11 to 90 mg HC/g TOC, oxygen index (OI) ranges from 1.08 to 31.82 mg CO2/gTOC, Tmax ranges from 431 to 525°C, production index (PI) ranges from 0.11–1.0. Unstructured organic matters are extracted through maceration techniques, which infer thermal maturity stages of the shales. The dark brown to black in colour of the studied palynomorphs extracted from the Rohtasgarh shales inferred strong thermal alternation of the source rock over geological time. High thermal alteration index (TAI) of Rohtasgarh shales (3.5) suggests the presence of post maturated organic matters with gas prone type III & IV kerogen. The organic richness, kerogen type, thermal maturity of Rohtasgarh limestone in the study area signify poor to fair hydrocarbon generation potential. [ABSTRACT FROM AUTHOR]

The pesticide p,p'-DDT (1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl) ethyl]benzene) has been used in agriculture, forestry, and vector control for decades. Technical DDT, the purity commonly used for insecticidal applications, contained p,p'-DDT as well as its constitution isomer o,p'-DDT (1-chloro-2-(2,2,2-trichloro-1-(4-chlorophenyl)ethyl] benzene) and several closely related compounds. To investigate the effect of environmental processes on the isomer-specific composition of DDT and its degradation products, we examined previously published and newly acquired quantitative data with regard to o,p'-/p,p'- DDX ratios in different environmental matrices. Isomeric shifts related to the depositional regime, transfer between and within compartments, and microbial transformation were clearly observed. Shifts of the positional isomer ratios potentially can serve as indictors to track the environmental fate of DDX. For an unambiguous assignment of these shifts to specific processes, further systematic studies and complementary lab experiments are necessary. [ABSTRACT FROM AUTHOR]

Anticoagulant rodenticides are used worldwide to control commensal rodents for hygienic and public health reasons. As anticoagulants act on all vertebrates, risk is high for unintentional poisoning of terrestrial and aquatic wildlife. Causative associations have been demonstrated for the unintended poisoning of terrestrial nontarget organisms. However, behavior and fate of anticoagulant rodenticides in the aquatic environment have received minimal attention in the past despite considerable acute toxicity of several anticoagulants to aquatic species such as fish. In light of recent regulatory developments in the European Union concerning rodenticides, we critically review available information on the environmental occurrence, fate, and impact of anticoagulant rodenticides in the aquatic environment and identify potential risks and routes of exposure as well as further research needs. Recent findings of anticoagulant rodenticides in raw and treated wastewater, sewage sludge, estuarine sediments, suspended particulate matter, and liver tissue of freshwater fish in the low ng/L and µg/kg range, respectively, demonstrate that the aquatic environment experiences a greater risk of anticoagulant rodenticide exposure than previously thought. While the anticoagulant's mechanism of action from the molecular through cellular levels is well understood, substantial data gaps exist regarding the understanding of exposure pathways and potential adverse effects of chronic exposure with multiple active ingredients. Anticoagulants accumulating in aquatic wildlife are likely to be transferred in the food chain, causing potentially serious consequences for the health of wildlife and humans alike. [ABSTRACT FROM AUTHOR]

The pesticide DDT (1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene) and its degradates are among the most persistent and abundant organochlorine contaminates in the environment, and DDT is still being produced in several Asian countries. In this study, we report for the first time on the detection of DDT-related compounds with one additional or missing chlorine atom at the phenyl group (DDX ±Cl ) in sediment and soil samples taken in the vicinity of former and current DDT production sites. These congeneric compounds most likely originate from production residues disposed of into the environment. In order to ensure an adequate identification and quantification of this novel organic pollutant group, individual DDX ±Cl were synthesized as reference compounds by simulating an impure production of DDT in the laboratory. In contrast to DDX ±Cl with (chloro)alkyl moieties, DDX ±Cl with (chloro)alkenyl moieties cannot be unambiguous assigned by gas-chromatographic/mass spectrometric (GC/MS) fragmentation and elution orders. The occurrence of DDX ±Cl in environmental samples allows to draw conclusions about the purity of the production process in the associated production sites. Moreover, they potentially can serve as molecular indicators to differentiate between industrial DDT emissions and insecticidal applications of DDT. This hypothesis has yet to be confirmed by further research. [ABSTRACT FROM AUTHOR]

Tsunami deposits originating from the 1755 CE Lisbon tsunami are known from the Spanish Gulf of Cádiz. The coastal areas around Conil de la Frontera were severely affected by the tsunami, with the destruction of the Conilete village, damages to the medieval Torre de Castilnovo, and inundation of low-lying areas of Conil de la Frontera (e.g., the old tuna factory La Chança). A tsunami wave train of at least three waves with inundation heights of up to 8 m has been reported in historical eyewitness documentation. Already, few studies have documented sedimentary remnants in the form of sandy units, and their inland extends in Conil de la Frontera and the adjacent alluvial plains of El Palmar de Vejer. Few studies along the coastal areas of the tsunami-affected Iberian Peninsula excavated trenches and pits for sampling. Yet, no study has investigated the 1755 CE tsunami deposits and their small-scaled sedimentological features in a high resolution along the cross-section of a sedimentological trench. This research presents a combined sedimentological, micropaleontological, and biogeochemical analysis of a coastline-perpendicular cross-section in a large-scale hand-dug trench (4.5 × 4.5 × 1 m) from the coastal alluvial plain of El Palmar de Vejer. By means of sediment-stratigraphic analysis, grain size and micropaleontological analyses, organic biogeochemistry, and photogrammetry the 1755 CE tsunami layer has been distinctly identified from its surrounding strata, and sedimentary structures resulting from small-scaled tsunami processes have been analyzed. • Study of a combined sedimentological, micropaleontology and biogeochemical analysis. • Coastline-perpendicular trench cross-section tracking the 1755 CE tsunami. • Sedimentary characteristics of the 1755 CE tsunami and their variability. • Application of biomarkers (n -alkanes, n -aldehydes, phytol derivates, fatty acids, hopanes, steranes). [ABSTRACT FROM AUTHOR]

The well-known 1755 CE Lisbon tsunami caused widespread destruction along the Iberian and northern Moroccan coastlines. Being affected by the powerful 1755 CE Lisbon tsunami, the southwestern Algarve shelf provides environments for detecting offshore tsunami imprints. Our multidisciplinary investigations (hydroacoustics, sedimentology, geochemistry, radiocarbon dating) of the Holocene sediments have revealed tsunami deposits linked to this tsunami and a ca. 3600 cal yr BP event. The latter event is until now unidentified in Portugal. Both event deposits contrast with the background shelf sedimentation by their coarser grain size, element composition, internal structure, and erosive base, making them discernible in the sub-bottom data and cores. Especially the ca. 3600 cal yr BP deposit is exceptionally well-preserved at one of the coring sites. The clear differentiation into several sections enables further insights into offshore tsunami transport and depositional processes. This study demonstrates that the record and preservation of tsunami deposits were possible on the Algarve shelf in specific locations sheltered from possible alterations. Our findings extend the tsunami catalogs of Portugal with a previously unknown tsunami dated to ca. 3600 cal yr BP. • Offshore tsunami deposits of the 1755 CE Lisbon and a previously unknown tsunami • The ca. 3600 cal yr BP tsunami extends the Portuguese tsunami catalog. • Characteristics of offshore tsunami deposits are strongly site-specific. • Tsunami backwash can transport sediments as grain or debris flows. [ABSTRACT FROM AUTHOR]

Various factors influence the isomeric composition of hexachlorocyclohexanes which are released to the environment. Original compositions in technical mixtures may vary slightly, but higher shifts are observable for transfer processes, bioaccumulation and microbial transformation. Consequently, the isomeric composition in environmental samples is a superposition of these processes. In this study, isomeric distributions and concentrations of hexachlorocyclohexanes were analyzed in water, sediment, and soil samples of a riverine system known to be highly contaminated by hexachlorocyclohexanes. To assess desorption of hexachlorocyclohexanes from particulate matter to water, batch shaking and percolation experiments were conducted complementary. Analyzed samples exhibited total hexachlorocyclohexane concentrations of up to 2.8 µg/g in sediments and up to 21 µg/L in river water predominated by the α-isomer. Downstream hexachlorocyclohexane pattern changed toward δ-isomer domination, while overall hexachlorocyclohexane concentrations decreased. Desorption experiments supported the assumption of discrimination by preferred association of the α- and β-isomers with particulate matter, showing elevated mobilization of γ-, δ- and ε-hexachlorocyclohexanes and lower mobilization of the α- and β-isomers. Soil samples of a riparian wetland exhibited elevated concentrations of hexachlorocyclohexanes exceeding 200 µg/g and predominance of α-hexachlorocyclohexanes in the top soil layer. Subjacent soil layers showed rapidly decreasing hexachlorocyclohexane concentrations and an isomeric shift toward the β-isomer. The assumed preferential mobilization of β-hexachlorocyclohexane was supported by desorption experiments. This study demonstrated firstly that transfer processes influence substantially hexachlorocyclohexane isomer distribution in the aquatic environment. Secondly, conditions of aging determine strength of association and remobilization potential of hexachlorocyclohexane residue down to an isomer-specific level. [ABSTRACT FROM AUTHOR]

The paper industry is one of the most significant industrial branches that contributes to water pollution. Recent studies regarding the chemical composition of wastewaters from modern paper production sites are sparse, and organic contaminants originating from this source may remain undetected and uncontrolled. Therefore, for this study, non-target screening analyses of wastewaters from five different paper production sites were performed, including an extended analysis of one facility, for the identification of volatile non-polar to semi-polar organic contaminants. The identified contaminants were also traced in the adjacent river. Several specific agents related to paper production, including photoinitiators, ink and thermal paper constituents, were present in most wastewaters and were therefore considered to be characteristic paper industry contaminants. A couple of contaminants identified in this study are being reported for the first time and might be toxic, but have been neglected in previous studies. Bisphenol A and 2,4,7,9-tetramethyl-5-decyne-4,7-diol were found in untreated wastewaters, treated wastewater and in river water. Bisphenol A was present in river water downstream from where the paper industry discharges at a concentration that was reported to affect the reproduction of gastropods. Thus, our findings imply that paper industry discharges pose a risk to the populations of sensitive macroinvertebrates. [ABSTRACT FROM AUTHOR]

The Nördlinger Ries in southern Germany contains a sequence of Miocene post-impact lacustrine sediments. To gain knowledge on the chemical composition and provenance of the organic matter (OM) through the up to 250 m thick sediment profiles, pyrolytic, organic geochemical and infrared spectroscopy measurements were performed on both sediments and concentrated OM. Type I kerogen prevails through the examined samples with high atomic H/C ratios (1.6 on average), hydrogen index (HI mostly >600 mg HC/g TOC), and spectral A - and C -factor values (mostly >0.8), but low oxygen index values (OI mostly <25 mg CO 2 /g TOC) for the concentrated OM. Exceptions occur in the uppermost Miocene sediments at the central site (Nördlingen-1973) and some marginal (SUBO-18) sediments containing hydrogen-lean type III kerogen having low H/C ratios (<1), HI (<300 mg HC/g TOC), spectral A - and C -factor values (<0.6), but high OI values (>40 mg CO 2 /g TOC). Mineral matrix effects induced by abundant clay minerals and zeolites significantly reduce the HI of bulk sediments as compared to concentrated OM. Organic sulfur-rich kerogen occurs in the basal units in the NR-1973 and occasionally in the SUBO-18 boreholes with high atomic S org /C org ratios >0.04 and pyrolytic thiophenes/toluene ratio > 13. Abundant pyrolytic alkanes/alkenes, high spectral A -factor and CH 2 /CH 3 values suggest prominent algal input to the OM for most of the samples. The aliphatic chain length of the kerogen decreases and the branching degree increases from the older, deeper to the younger, shallower deposits. While oxygen-bearing organic constituents are common, nitrogen-bearing moieties are rare. A general structural model is established for the type I sulfur-rich, Miocene kerogen of the Nördlinger Ries paleo-lake. • First detailed description of kerogen evolution in thick, Miocene crater lake sediments. • Curie Point pyrolysis provides important clues on provenance of organic matter. • Structure of rare, lacustrine type I sulfur-rich kerogen is discussed. • Impact of lake chemistry on kerogen structure is evident. [ABSTRACT FROM AUTHOR]

Environmental processes can affect the stereochemical properties of organic pollutants. In particular, biotic processes like microbial transformations or membrane penetration alter the ratios of enantiomers as well as diastereomers. These effects have been intensively used not only in environmental studies but also in medicine, toxicology, pharmacy, and agricultural sciences. However, in order to identify unambiguously biotic-initiated alteration of organic compounds, the knowledge on the stereoselective effect of all relevant processes is mandatory. Therefore, here we report the first evidence for a stereospecific formation of non-extractable residues of a xeniobiotic in a highly relevant soil subfraction, the organo-clay complexes. In this study, soils were spiked with labeled and unlabeled nonylphenol isomer, and incubation experiments were performed to study its long-term incorporation behavior into soil-derived organo-clay complexes under abiotic and biotic conditions. Besides the extractable particle-associated proportion especially the humic fractions comprising the bound residues have been analyzed by GC/MS. Our results from biotic experiments revealed alterations of the diastereomeric composition of the contaminant in the different soil humic subfractions. A depletion of the first eluting diastereomer as expressed by diastereomeric ratios around 0.6 has been observed for the extractable fraction, whereas the non-extractable proportion was enriched in the first diastereomer (diasteremoric ratio around 1.0). On the contrary, the diastereomeric ratios remained unaffected during the abiotic experiments (diasteremoric ratio around 0.8). These systematic observations give clear evidence that the process of microbial-assisted incorporation of nonylphenol into soil organo-clay complexes is a stereoselective process. To our knowledge, this is the first report on a stereoselective incorporation process of organic substances forming non-extractable residues. Consequently, the formation of non-extractable residues has to be considered in environmental studies dealing with stereoselective analysis of organic pollutants in soils to study their microbial transformation. [ABSTRACT FROM AUTHOR]

The molecular and isotopic composition of biomarkers in initial bitumen isolated from immature (0.41% Rr) oil shale samples (Aleksinac deposit) and liquid products obtained by pyrolysis in open (OS) and closed (CS) systems are studied. The influence of pyrolysis type and variations of kerogen type on biomarkers composition and their isotopic signatures in liquid products is determined. The applicability of pyrolysis type, numerous biomarkers and carbon isotopic compositions (δ13C) of n -alkanes in liquid pyrolysates is established. Pyrolysis experiments were performed on two selected samples that showed high content of total organic carbon and hydrocarbon generation potential, but also certain variations in sources/depositional environment of organic matter (type I and mixed type I/II kerogen) within previous research of the oil shales sample set. The biomarker signatures were evaluated using gas chromatography-mass spectrometry (GC-MS) and δ13C of individual n -alkanes in bitumen and liquid pyrolysates. The molecular composition of liquid pyrolysates from the OS is very similar to those in initial bitumen, independently on kerogen type, confirming algal origin of organic matter (OM) deposited in lacustrine environment, even more apparently than results of initial bitumen. Therefore, OS can be useful for assessment of source and depositional environment of OM. Pyrolysis in the CS caused more intense thermal alterations, therefore the source fingerprints sometimes notably disappear. The liquid pyrolysates from the CS have the distributions of biomarkers similar to those in crude oils. The biomarker maturity parameters showed slightly higher values in the CS pyrolysate of mixed type I/II kerogen in relation to type I kerogen. δ13C of n -alkanes in liquid pyrolysates from the OS are isotopically lighter in comparison to bitumen, independently on kerogen type. Oppositely, in liquid pyrolysates from the CS, they become heavier than in bitumen, indicating the thermal influence on δ13C signatures, with more pronounced difference for type I kerogen. • Open system pyrolysis is useful for determination of organic matter sources, independently on kerogen type. • Pyrolysis of oil shale in closed system generates liquid product comparable to crude oil. • Mixed type I/II kerogen attained slightly higher maturity than type I kerogen by closed system pyrolysis. • δ13C of individual n -alkanes displayed notable variations depending on pyrolysis type. [ABSTRACT FROM AUTHOR]

The article introduces the editors of this journal's "Sediments" area. Thomas Knacker is the subject editor in "Sediments" section 1: sediment quality and impact assessment. Marc Babut and Lasse Gerrits are the subject editors in section 2: sediment risk management and communication. Henner Hollert and Philip Owens are the subject editors in section 3: sediment management at the river basin scale. Kay Hammer is the subject editor in section 4: sediment and dredged material treatment.

While it is well recognized that the frequency and intensity of flood events are increasing worldwide, the environmental, economic, and societal consequences of remobilization and distribution of pollutants during flood events are not widely recognized. Loss of life, damage to infrastructure, and monetary cleanup costs associated with floods are important direct effects. However, there is a lack of attention towards the indirect effects of pollutants that are remobilized and redistributed during such catastrophic flood events, particularly considering the known toxic effects of substances present in flood-prone areas. The global examination of floods caused by a range of extreme events (e.g., heavy rainfall, tsunamis, extra- and tropical storms) and subsequent distribution of sediment-bound pollutants are needed to improve interdisciplinary investigations. Such examinations will aid in the remediation and management action plans necessary to tackle issues of environmental pollution from flooding. River basin-wide and coastal lowland action plans need to balance the opposing goals of flood retention, catchment conservation, and economical use of water. [Display omitted] • Flood-induced mobilization of contaminated sediment poses significant risk. • Scientific, economic, and political consequences of flood events in a global context. • Risks and tools to investigate effects of contaminant remobilization during floods. [ABSTRACT FROM AUTHOR]

Due to the high population density and sensitive infrastructures, coastal areas are highly vulnerable to various geohazards such as tsunamis. The impact of tsunamis is traceable in sedimentary archives providing an important tool for reconstructing these events. Here, geochemical and physical evidence of the resulting inundations have been discussed over the last years with increasing interest on identifying and using highly specific tsumanite indicators. To investigate a broader range of potential organic indicators, a multi-tiered geochemical analysis has been applied on tsunami deposit from Japan and Hawaii in this study with the aim to detect and quantify a more comprehensive set of suitable marker compounds. Both areas of investigation differed especially in terms of population and anthropogenic influence. The analyzed fractions of organic matter covered not only the low molecular weight compounds of the extractable and hydrolysable fraction (a part of the non-extractable fraction), but also the macromolecular matter. Three consecutive analytical approaches including extraction, alkaline hydrolysis and pyrolysis have been applied on the sedimentary organic matter to study their potential to contrast between tsunami and non-tsunami layers. The analyses of compound ratios as well as individual concentration profiles in tsunami and non-tsunami layers revealed two parameters, the TAR FA (terrigenous to aquatic ratio of fatty acids) and the C 29 /C 27 sterol ratio, which exhibit a high potential to act as tsunamite indicators. Further parameters (TAR ALK - terrigenous to aquatic ratio of n -alkanes, concentration profiles of long-chain n -aldehydes) showed a minor potential but are worth to be considered in organic geochemical analyses of tsunami affected sediment archives in the future. • Comprehensive analyses of organic tsunami indicators in sedimentary archives. • Comparison of indicators in three different organic matter fractions. • Identification of independent organic marker ratios and compounds. [ABSTRACT FROM AUTHOR]

• Critical assessment of specific pyrolysis products used for quantification. • Off-line pyrolysis as suitable tool for quantification of polymers. • Sample matrix has an important influence on quality of analytical pyrolysis. Although pyrolytic analysis of polymers allows a quantitative determination, reports on pyrolysis-based quantifications are very scarce, most probably as the result of some critical aspects that need to be considered. This is valid especially for environmental analysis of microplastics that require a detection at low concentrations in complex matrices. Therefore, an off-line pyrolysis approach to quantify five polymers representing the most relevant constituents of microplastics (polyethylene PE, polypropylene PP, poly(ethylene terephthalate) PET, polystyrene PS, poly(vinyl chloride) PVC) was studied. The analytical approach was critically evaluated and discussed covering the basic analytical parameters specificity, sensitivity, reproducibility and applicability on real samples. Off-line pyrolysis-based analysis of PS and PP provided the best results with a high specificity of pyrolysis products, very good limit of quantification around 1 to 3 μg based on S/N ratios as extrapolated from standard material analyses (without matrix effects) and a recovery from real sample matrix higher than 50%. Hence, for these synthetic polymers the presented analytical method exhibits a high potential for quantification at low concentration levels in real environmental samples. Although for PE a partly lower specificity of pyrolysis products, a little lower sensitivity and reproducibility but a very good recovery from real sample matrix can be summarized, the off-line pyrolysis-based approach seems to be applicable successfully also for PE. Analyses of PVC and PET revealed the highest inconsistencies and drawbacks in particular only minor specificity, less reproducibility and a low recovery. Thus, both polymers can be quantified only with a very low degree of reliance and need complementary analysis to verify the pyrolysis-based quantitative results. Noteworthy, most of the critical aspects revealed by this study are also worth discussing for on-line pyrolysis approaches. [ABSTRACT FROM AUTHOR]

A sample set consisting of coal, overlying and intercalating siliciclastic rocks and kerogen concentrated from these rocks of nine Pennsylvanian subbituminous to bituminous coal seam intervals from the German Ruhr Basin was analysed in order to detect chemical structural differences of the organic matter. Vitrinites from the coal seams and the kerogen concentrates were isolated to study effects of maceral group composition on chemical properties of typical type III kerogen. Rock-Eval T max values of sediment samples are higher than both those of the kerogen concentrated from them and associated coal samples. This is a result of the mineral matrix effect. Higher OI values of the sediment and kerogen samples as compared to those of the bulk coal samples cannot be explained by the abundance of carbonyl/carboxyl groups as reflected by results obtained by attenuated total reflectance (ATR) FT-IR spectroscopy. Ratios of the areas of the aromatic γCH out of plane, the aliphatic νCH x stretching, and the aromatic νC=C ring stretch regions imply a lower degree of aromaticity and at the same time higher degree of condensation of vitrinites originated from the sedimentary layers, respectively. Upon Curie Point (CP) pyrolysis at 590 °C, these vitrinite samples generate higher amounts of long-chained normal alkanes and n -alkenes than the bulk samples or the vitrinite originating from the coals. While reflectance values of vitrinites from coals and sedimentary layers are within the standard deviation of values expected for the narrow maturity window, only the vitrinites of the coal seams show some correlation with depth. Clearly, the relative abundance of phenols is decreasing with increasing maturity, as well as the ratio of benzenes over higher condensed aromatic moieties as revealed by their pyrolysis products generated at 764 °C. • Comparative structural study of coals, associated kerogens, and isolated vitrinites. • Structural differences of organic matter as related to surrounding matrix material. • Quantification of differences in reflectance and pyrolysis products of vitrinite. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants in large urban agglomerations are worldwide among the main sources of emerging contaminants in aquatic systems. The present study is a first comprehensive characterization of potentially harmful emerging contaminants in sewage of a Chinese urban area. The study area Haikou City is located at the coast of tropical Hainan Island. A GC/MS based non-target screening approach for the identification of a wider range of lipophilic to semi-polar organic sewage constituents was applied. Pollution originating from sewage was tracked in the urban coastal waters by using selected source-specific indicators. A set of sewage constituents with a high structural diversity was identified comprising both, industrial and household chemicals. Ingredients of personal care products, pesticides and pharmaceuticals were found, that were rarely reported from other regions of the world. This observation might be attributed to different environmental legislation and consumption habits in China. Exceptionally high concentrations of the illegal drug ketamine with up to 1100 ng L−1 were detected, suggesting its high popularity and consumption rate. Noteworthy, sewage constituents reported here for the first time were the pharmaceuticals marmesin, oxolamine and ansimar also with high concentrations of up to 1200 ng L−1. Elevated concentrations of sewage indicators in the main city area suggest the overflow of the sewage system, in particular in the period of a typhoon event. Tracing the sewage contamination in the surface water system of the coastal urban area of Haikou revealed a lower level of pollution. The concentration ranges point to no acute risks for the coastal ecosystem due to sewage inputs from the city area. Generally, the detected spectrum of municipal emerging contaminants has to be considered for the testing and technical improvement of wastewater treatment techniques, for regular monitoring of the surface water quality and for environmental impact assessment in China. Furthermore, the compound spectrum reported here is a good reference point for the composition of municipal sewage in other emerging economies. Image 1 • Non-target screening of treated and untreated municipal wastewaters from Asia. • High structural diversity of organic contaminants in the domestic wastewaters. • PCPs and pharmaceutical drugs rarely reported from other world regions were detected. • High concentrations of illegal drug ketamine suggest its high popularity in the area. • No acute risks for the coastal ecosystem are related to sewage inputs from the city. [ABSTRACT FROM AUTHOR]

Tropical coastal ecosystems are particularly at threat from land-sourced pollution, resulting from the input of harmful substances from a multitude of emission sources. Although not intensively studied to date, this concerns also the contamination of coral reefs with pesticide classes apart from the frequently reported organochlorine pesticides. We therefore investigated the occurrence and spatial distribution of these compounds in water samples from the northeast coast of Hainan, a tropical Chinese island. The study area included two sensitive coastal habitats: a shallow bay and fringing coral reefs with seagrass beds. The results revealed the occurrence of photosystem(II) triazine herbicides at most sampling stations in the coastal waters, especially of prometryn (maximum concentration 440 ng L−1). A chemical characterization of aquaculture pond waters gave evidence that aquaculture was the source of this contamination. Prometryn was detected in many sampled ponds and could thus be useful as source-specific molecular indicator to trace aquaculture emissions in coastal areas. Concentrations of triazine herbicides in the study area (<10–440 ng L−1) were lower than reported acute effect concentrations for dinoflagellates, seagrass and algae. Thus, no acute toxic effects on local coral reefs and seagrass beds are expected. Chronic exposures of sensitive species to low concentrations of the detected triazine herbicides have to date not been studied. Therefore, we cannot exclude deteriorating effects in the long-term, especially in combination with other stressors such as rising sea surface temperature, which can enhance the sensitivity to pollutants. Future studies in other world regions should consider prometryn and further triazine herbicides as harmful pollutants from aquaculture emissions. Image 1 • Study on the contamination of a tropical coastal area with pesticides. • Photosystem(II) herbicides frequently occurred in a shallow bay and coral reefs. • Aquaculture effluents were the source of the detected photosystem(PS)(II) herbicides. • Herbicide concentrations lower than reported acute toxicity thresholds for corals. • Prometryn as molecular indicator to trace aquaculture emissions in the environment. [ABSTRACT FROM AUTHOR]

Organic geochemistry is commonly used in environmental studies. In tsunami research, however, its applications are in their infancy and it is still rarely used. We present results for two types of organic geochemical markers, biomarkers and anthropogenic markers, present in deposits left by 2011 Tohoku-oki tsunami on the Sendai Plain, Japan. As the tsunami inundated the coastal lowland up to 4.85 km inland, sediments from various sources were eroded, transported and deposited. This led to the distribution of biomarkers from different sources across the Sendai Plain creating a unique geochemical signature in the tsunami deposits. The tsunami also caused destruction along the Sendai coastline, leading to the release of large quantities of environmental pollutants (e.g., fossil fuels, tarmac, pesticides, plastics, etc.) that were distributed across the inundated area. These anthropogenic markers, represented by three main compound groups (polycyclic aromatic hydrocarbons, pesticides, and halogenated compounds), were preserved in tsunami deposits (at least until 2013, prior to land clearing). Their concentrations differed significantly from the pre- and post-tsunami background contamination levels. Organic proxy concentrations can differ for sand and mud deposits due to various factors (e.g., preservation, dilution, microbial alteration). However, it can be concluded that anthropogenic markers and biomarkers have the potential to be a valuable proxy for future studies of recent tsunami deposits because of their high source specificity and relatively good preservation potential providing information about sediment sources and transport pathways (e.g., marine source, evidence of backwash). • Study testing the application of anthropogenic markers and biomarkers for identification of tsunami deposits. • Organic-geochemical investigation of 2011 Tohoku-oki tsunami deposits from the Sendai Plain, Japan. • Distinct differentiation of tsunami deposits geochemical signature from pre- and post-tsunami deposits. • Identification of compound groups (i.a., polycyclic aromatic hydrocarbons, n -alkanes, pesticides, halogenated compounds). • Verification of prior research results from the Sendai Plain with results from organic-geochemical analysis. [ABSTRACT FROM AUTHOR]

In order to recognize organic contaminants responsible for ecological stresses from intensive shipping traffic and dockyard works, this study aimed at characterizing the sediment contamination of a large industrialized port located in Hainan Island, China. Surface sediment samples were collected from 17 stations including the main docks, the dockyards and the major industrial wastewater outlets. Organotin compounds, the pesticide DDT (bis(chlorophenyl)trichloroethane) and its metabolites and polycyclic aromatic compounds were identified as main pollutant groups by GC/MS applying a non-target screening approach. The pesticide DDT and its metabolites were found in the same samples as the organotin derivatives pointing to similar emission sources. The concurrent presence of these compounds in the dockyard samples suggests a combined usage of organotin compounds and DDT as active ingredients in antifouling paints in Yangpu. As highly specific molecular indicators for dockyard activities, butyltin and phenyltin compounds were identified. Noteworthy, also tributylmethyltin and triphenylmethyltin were detected, likely resulting from microbial assisted biomethylation of synthetic organotin compounds in the sediments. The concentrations of PAHs, DDX and TBT in sediments from dockyards exceeded global sediment quality guidelines and the toxicity thresholds, and potentially have adverse biological effects on marine organisms. • Intensive shipping traffic and dockyard works discharge pollution in China. • Butyltin and phenyltin derivatives are highly specific molecular indicators. • DDX and PAHs are indicators of minor significance. • A clear impact on benthic ecosystems is evident. [ABSTRACT FROM AUTHOR]

• AOHs with different molecular structures showed distinct NER formation mechanisms. • Covalent binding was found favorable for monocyclic AOHs with hydrophilic groups. • Physical entrapment impacted most on polycyclic and hydrophobic monocyclic AOHs. • Monocyclic AOHs with hydrophilic groups showed highest remobilization potential. Anthropogenic organohalogens (AOHs) are toxic and persistent pollutants that occur ubiquitously in the environment. An unneglectable portion of them can convert into nonextractable residues (NER) in the natural solid substances. NER-AOHs are not detectable by conventional solvent-extraction, and will get remobilized through changes of surrounding environment. Consequently, the formation and fate of NER-AOHs should be investigated comprehensively. In this study, solvent extraction, sequential chemical degradation and thermochemolysis were applied on different sample matrices (sediments, soils and groundwater sludge, collected from industrial areas) to release extractable and nonextractable AOHs. Covalent linkages were observed most favorable for the hydrophilic-group-containing monocyclic aromatic AOHs (HiMcAr-AOHs) (e.g. halogenated phenols, benzoic acids and anilines) incorporating into the natural organic matter (NOM) as NER. Physical entrapment mainly contributed to the NER formation of hydrophobic monocyclic aromatic AOHs (HoMcAr-AOHs) and polycyclic aromatic AOHs (PcAr-AOHs). The hypothesized remobilization potential of these NER-AOHs follow the order HiMcAr-AOHs > HoMcAr-AOHs/ aliphatic AOHs > PcAr-AOHs. In addition, the NOM macromolecular structures of the studied samples were analyzed. Based on the derived results, a conceptual model of the formation mechanisms of NER-AOHs is proposed. This model provides basic molecular insights that are of high value for risk assessment and remediation of AOHs. [ABSTRACT FROM AUTHOR]

• Systematic evaluation of biomarker maturity parameters and their ranges. • Aromatic maturity parameters mirror maturation in and beyond oil window very well. • Strong concentration decrease of non-aromatic and aromatic polycyclic biomarkers within oil window. • Only weak weathering of cores after 40 years of dry storage. A total of 30 core samples of organic matter-rich Lower Toarcian shale (Posidonia Shale) were geochemically analyzed to study systematic changes in the quantitative and qualitative composition of specific biomarkers at different thermal maturities ranging from 0.48 to 1.45% vitrinite reflectance (VR r). The samples are derived from 5 wells (Hils Syncline, NW Germany) each representing a different level of maturation (0.48, 0.68, 0.73, 0.88, 1.45 %VR r). In NW Germany, Posidonia Shale was deposited under marine, oxygen-deficient bottom water containing initially high amounts of TOC (above 10%) and marine type I-II kerogen. Upon maturation, organic carbon has been lost and hydrogen index values have decreased. Biomarker ratios reflecting this maturation very well include ratios of short over long-chain n -alkanes, ratios of pristane and phytane over n C 17 and n C 18 , Ts/(Ts + Tm), C 29 Ts/(C 29 Ts + C 29 H), ratios based on DMDBTs, and TA(I)/TA(I + II) ratios (triaromatic steroids). The evolution of different steroid-, hopane-, naphthalene-, phenanthrene- and dibenzothiophene-related parameters is documented and compared to literature. Concentrations of individual hydrocarbons were measured in order to obtain quantitative data on biomarker abundance and their evolution upon maturation. Whereas there is a general trend of increasing biomarker content from immature (0.48 %VR r) to early mature (0.68 %VR r) conditions and of decreasing biomarker content with maturation from 0.68 to 0.88 %VR r , there are some exceptions from this trend, especially at low levels of maturity. Almost no polycyclic biomarkers were detected at the highest maturity level of 1.45 %VR r in well Haddessen, where n -alkanes and aromatic hydrocarbons are predominant. The overall pattern of polycyclic biomarker abundance is not only determined by isomerization and aromatization processes, but mainly by preferential degradation of thermally less stable biomarkers leading to the observed modifications of biomarker maturity parameters. Furthermore, outer and inner sections from the 10 cm wide cores were compared in order to find out, whether 40 years of dry storage in a core repository affected the biomarker parameters. No significant and systematic differences have been observed, with exception of the most mature Haddessen well, where low molecular weight n -alkanes (< n C 21) are more abundant in the outer part. [ABSTRACT FROM AUTHOR]