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Polychlorinated biphenyls (PCBs) were quantified in 18 surface sediment samples, 1 sediment core, and several mangrove tissue samples collected in Jobos Bay, Puerto Rico in September 2013. Total PCBs in surface sediments ranged from 0.42 to 1232ngg -1 dw. Generally, higher levels were observed near-shore close to urban and industrial areas. The levels suggest significant pollution in Jobos Bay with respect to PCBs. Two-thirds of the sites were dominated by lighter PCB congeners (tri- to penta-chlorinated PCBs) while one-third had heavy PCB congeners (hexa- to octa-chlorinated PCBs) dominant. Total PCBs in a sediment core indicated levels fluctuating according to historical usage patterns. Total PCBs were measured in mangal leaves (14-747ngg -1 dw), roots (0.26-120ngg -1 dw), and seeds (16-93ngg -1 dw), suggesting bioaccumulation from sediments. This is the first report of a historical profile of PCBs in the study area and of PCB bioaccumulation in mangroves. This article provides new and useful information on PCBs in the Caribbean area of the GRULAC region., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Atmospheric particle associated with pyrogenic polycyclic aromatic hydrocarbons (PAHs) poses serious threats to human health by inhalation exposure, especially in semiarid areas. Hence, the distributions of PAHs and particle size in two core sediments collected from Lake Lianhuan, Northeast China were studied. The sediments were dated radiometrically, and particle size distribution and PAH concentration were evaluated and potential human health risk was assessed. From 1980 to 2007, the dominant PAHs in the two cores were 2- and 3-ring PAHs, and the concentrations of 3-6 ring PAHs gradually increased from the early 1990s. Diagnostic ratios indicated that pyrogenic PAHs were the main sources of PAHs which changed over time from combustions of wood and coal to liquid fossil fuel sources. Fine particles (<65 μm) were the predominant particle size (56-97%). Lacustrine source (with the peak towards 200-400 μm) and eolian sources derived from short (2.0-10 and 30-65 μm) and long (0.4-1.0 μm) distance suspension were indentified from frequency distribution pattern of particle size. Significant correlations between 3-6 ring PAHs (especially carcinogenic 5-6 ring PAHs) and 10-35 μm particulate fractions indicated that eolian particles played an important role in adsorbing pyrogenic PAHs. Petroleum source of PAHs was only identified during the 1980s in one core sediments, in which positive correlations between 2-ring PAHs and particulate fractions of >125 μm were found. Future research should focus on the seven carcinogenic pyrogenic PAHs due to a rapidly increasing trend since 1995 based on the assessment of toxic equivalency factors., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Previously published estimates of the global production, consumption and atmospheric emissions of 22 individual PCB congeners [Breivik K, Sweetman A, Pacyna JM, Jones KC. Towards a global historical emission inventory for selected PCB congeners - a mass balance approach. 1. Global production and consumption. Sci Total Environ 2002a; 290: 181-198.; Breivik K, Sweetman A, Pacyna JM, Jones KC. Towards a global historical emission inventory for selected PCB congeners--a mass balance approach. 2. Emissions. Sci Total Environ 2002b; 290: 181-198.] have provided useful information for later studies attempting to interpret contaminant levels in remote areas as well as in the global environment. As a result of the need for more contemporary emission data (following the year 2000), an update of this emission database is presented. This exercise takes into account new information on PCB production in Poland, as well as new data on the chemical composition of various technical mixtures for which less information had been available. The methodology to estimate temporal trends of PCB emissions associated with various types of PCB usage is improved. Projected emissions up to year 2100 are presented to facilitate predictions of future environmental exposure. The national emission data for each of the 114 countries considered is spatially resolved on a 1 degrees x1 degrees grid for each congener and year, using population density as a surrogate.

The flows of foodstuffs (and the nitrogen they contain) through the city of Paris in the 19th and early 20th century were evaluated. Between 1801 and 1914, the fivefold increase in the population of Paris, as well as the threefold increase in the number of horses used in urban transport, gave rise to increased needs for food and feed. The corresponding inputs of nitrogen increased from 6000 tN/year in 1817 to 25,000 tN/year from the rural hinterland to the city. The corresponding per capita inflows were relatively stable throughout the period and may be divided into four more or less equal parts (flour, meat, other human foodstuffs, forage), each representing about 6 gN per inhabitant per day. In total, the demand for foodstuffs was of the order of 24 gN per inhabitant per day, one quarter of which was for transport. The fate of this dietary nitrogen after consumption changed a lot with the techniques used for exploiting urban excreta of all kinds, particularly of nitrogen, which was in great demand until the development of synthetic fertilizers. Dietary nitrogen flow diagrams are established for the years 1817, 1869 and 1913, and reveal an increasing improvement of the agricultural reuse (from 20 to 40% of the inflowing N).

The European Heavy Metals in Mosses Surveys measure and map environmental concentrations of metals at more than 7000 sites in Europe. In Germany, moss samples were taken at 592 sites in 1990, at 1026 sites in 1995, and at 1028 sites in 2000, where up to 40 metals were measured each time. This article is about how to calculate multi-metal indices from the site- and metal-specific monitoring data and how to link them with the natural regions (ecoregions) of Germany. The ecoregions were calculated with surface data on natural vegetation, elevation, soil texture and climate by means of Classification and Regression Trees (CART). The ecoregions were mapped by GIS and superimposed on a map of multi-metal bioaccumulation indices calculated by means of geostatistics and percentile statistics from the monitoring data. These indices integrate the concentrations of 8 metals measured in 1990, 1995, and 2000 or 12 metals from the 1995 and 2000 surveys, respectively, and the ecoregionalisation enables their geostatistical estimates to be grouped into 21 ecological land categories. This two-step aggregation revealed that, from 1990 to 2000, the multi-metal metal accumulation declined up to 80%, varying with the ecoregions. Based on the multi-metal accumulation index hot spots, the metal accumulation was mapped, ecoregionalised, and suggested for further ecotoxicological assessment. Thus, the approach helps to assess the metal bioaccumulation within ecoregions in a comprehensive and holistic manner over time, space, and metals. This data aggregation is of importance for the environmental reporting in Germany and within the framework of the international environmental information systems. Furthermore, ecoregions may help to plan and optimize monitoring networks. Because monitoring should measure and estimate not only the environmental concentrations of substances but also their impacts on ecoregions, the number of monitoring sites should be proportional to the areas covered by the ecoregions and located according to their spatial variation.

Objectives: The fatty acid composition and other nutrients in traditional Inuit food appear to provide some protection against diseases of affluent industrialized societies, such as cardiovascular diseases and type 2 diabetes. A transition towards increased amounts of imported food might increase the occurrence of these diseases among Inuit. However, since the 1970s it has become evident that the marine-based Inuit diet also contains high levels of potentially toxic lipophilic organic pollutants and heavy metals. Since these two opposing effects on health appear to be inseparable, the phenomenon has become known as "The Arctic Dilemma". However, both the fatty acid composition and the contaminant levels vary in Greenlandic food items. Thus, in theory, it is possible to compose a diet where the benefits outweigh the risks. Our objective was to compare traditional and modern meals in Greenland regarding dietary composition, content of n-3 fatty acids and contaminants., Study Design: The present study was part of the Arctic Monitoring and Assessment Programme, AMAP, comparing the results of dietary composition and nutrients in 177 traditional meals collected in Uummannaq municipality, north Greenland in 1976 with 90 meals sampled in Uummannaq town in 2004 under similar conditions. Eleven pesticides, 14 PCB congeners, heavy metals, selenium, and fatty acids were analysed in meals and blood samples from the participants. Contaminant levels were compared between 1976 and 2004 after adjustment for n-3 fatty acids, indicating local food content., Results: Between the traditional meals collected 30 years ago and the meals from 2004, dramatic and significant changes have occurred in the dietary composition. The percentage of local food has decreased, and with it the intake of n-3 fatty acids. Calculated as daily intake, all but three contaminants had decreased significantly. However, this could be explained by the lower intake of local food. After adjustment for n-3 fatty acid content in the food, significant declines of concentration in the local food were evident only for PCBs and lead, whereas for mercury, DDTs, and chlordanes the levels were unchanged, and for hexachlorobenzene, mirex, and toxaphenes, the levels had increased significantly., Conclusion: The consumption of locally produced food has decreased in Greenland during the last 30 years and this has led to a reduction in the daily intake of contaminants. However, the concentrations of contaminants in local food items have not decreased, except for PCB and Lead. Therefore, we recommend that the consumption of local products is not increased beyond the present level, until the level of contaminants is reduced to a safer level.

The validity of the use of sycamore (Acer pseudoplatanus) tree-rings for the reconstruction of atmospheric lead pollution histories was investigated. Tree cores spanning 1892-2003 were collected from several sycamores from the eastern shore of Loch Lomond, Scotland, an area with no local point sources of lead emission. The lead concentration and 206Pb/207Pb profiles of the Loch Lomond region cores were compared with corresponding data for the 210Pb-dated loch sediment, and also with data for moss of known age from a Scottish herbarium collection. Two of the seven sycamore cores showed the same lead concentration trend as the lead flux to the loch, the rest having no similarity to either each other or the loch sediment record. Two further sycamore cores showed some similarity in their temporal 206Pb/207Pb trends to those seen in the sediment and moss records, but only in part of their profiles, whilst the 206Pb/207Pb ratios of the other sycamore cores remained relatively unchanged for the majority of the time covered, or exhibited an opposite trend. The 206Pb/207Pb ratios of the tree cores were also mostly higher than those of the previously established records for any given time period. Tree cores covering 1878-2002 were also collected along transects from Wanlockhead and Tyndrum, two areas of former lead mining and smelting associated with distinct 206Pb/207Pb ratios of 1.170 and 1.144, respectively. The Wanlockhead tree cores exhibited a generally decreasing trend in lead concentration with both time and distance from the lead mine. The characteristic 206Pb/207Pb ratio of 1.170 was observed in samples close to the mine but a decrease in the influence of the mine-derived lead was observed in more distant samples. The tree sampled at Tyndrum showed elevated lead concentrations, which decreased with time, and a fairly constant 206Pb/207Pb ratio of 1.15 reflecting input from the mine, features not observed in any other trees along the transect. Overall the data suggest that sycamore tree-ring analysis is an unsuitable method for obtaining records of historical lead deposition in areas with no large local lead input, although it can reveal some information about the temporal and spatial influence of point source emitters. The unsuitability probably arises from the number of active annual rings in a single year, the post-uptake radial translocation of elements, the relative importance of the different routes of uptake, and the soil depth(s) from which trees draw nutrients.

The concentration of the metals lead, copper, zinc, cadmium and iron was determined in bone remains belonging to 30 individuals buried in the Region of Cartagena dating from different historical periods and in eight persons who had died in recent times. The metals content with respect to lead, cadmium and copper was determined either by anodic stripping voltammetry or by atomic absorption spectroscopy on the basis of the concentrations present in the bone remains. In all cases, zinc and iron were quantified by means of atomic absorption spectroscopy. The lead concentrations found in the bone remains in our city are greater than those reported in the literature for other locations. This led to the consideration of the sources of these metals in our area, both the contribution from atmospheric aerosols as well as that from the soil in the area. Correlation analysis leads us to consider the presence of the studied metals in the analysed bone samples to be the consequence of analogous inputs, namely the inhalation of atmospheric aerosols and diverse contributions in the diet. The lowest values found in the studied bone remains correspond to the Neolithic period, with similar contents to present-day samples with respect to lead, copper, cadmium and iron. As regards the evolution over time of the concentrations of the metals under study, a clear increase in these is observed between the Neolithic period and the grouping made up of the Bronze Age, Roman domination and the Byzantine period. The trend lines used to classify the samples into 7 periods show that the maximum values of lead correspond to the Roman and Byzantine periods. For copper, this peak is found in the Byzantine Period and for iron, in the Islamic Period. Zinc shows an increasing tendency over the periods under study and cadmium is the only metal whose trend lines shows a decreasing slope.

In this study we present a novel comparison of three proxy indicators of paleoproductivity, pigments, biogenic silica (BSi), and cysts of autotrophic dinoflagellates measured in cored sediments from New Bedford Harbor, Massachusetts. In addition to detailed historical reports we use palynological signals of land clearance, changes in the ratio of centric and pennate diatoms, sedimentary organic carbon and stable carbon isotopes to constrain our interpretations. Our study spans the period from prior to European settlement to approximately 1977, during which watersheds were cleared, port development occurred and much of the coastal property became industrialized. The combined effects of nutrient loading from watershed clearance and urban sewage on the estuarine ecosystem shifted not only levels of primary production, but also the nature of the production. Our proxies show that when European colonists first arrived the estuarine production was benthic-dominated, but eventually became pelagic-dominated. Importance of water column production (by diatoms and dinoflagellates) rapidly increased as soil nitrogen was released following forest clearance. Stabilization in rates of forest clearance is reflected as a decline in production. However, population increases in the urbanizing watershed brought new sources of nutrients through direct sewage discharge, apparently again stimulating primary production. We assume that early 20th century changes in sewage discharge and introduction of heavy metals into Harbor waters caused a temporary reduction in primary production. The introduction of a new sewer outfall near the core site and changes in estuarine hydrography due to construction of a hurricane barrier across the mouth of the harbor are reflected by renewed water column production, but decreases in the population of diatoms and dinoflagellates. Fossil pigments suggest renewed water column production in the latest years recorded by our sediment core.

Lead concentration and isotope ratio data are presented for the tooth enamel of 77 individuals buried in England and spanning approximately 5000 years from the Neolithic until the 16th century AD. Whereas other tissues may be affected by diagenesis in the burial environment, the Pb concentration of tooth enamel is directly related to childhood exposure. This record is preserved post-mortem and over archaeological time. Tooth enamel Pb concentrations in the prehistoric period appear to be variable within the range 0.04 to approximately 0.4 ppm, with occasional higher levels. The Romano-British and medieval periods show a marked increase in Pb exposures with enamel concentrations reaching up to approximately 40 ppm. These exposures would today be associated with industrial pollution. Exposures appear to be highly variable compared with modern people, however, with many medieval individuals having very low enamel Pb concentrations comparable with prehistoric people. Lead isotope data refine this picture. We distinguish between the diverse isotopic ratios we believe to be characteristic of 'natural' exposure to Pb-from geological sources via the diet-and the much narrower isotopic range characteristic of exposure to technological Pb from ore sources. Taken together the data suggest that the maximum concentrations associated with 'non-technological' exposure at any period are approximately 0.5-1.0 ppm, similar to that reported for modern people in England.

Sediments record the history of contamination to estuaries. Analysis of the concentrations of toxic organic compounds, contaminant and crustal metals, organic carbon content and isotopic composition in sediment cores from two estuarine systems in Buzzards Bay allowed reconstruction of human impacts over 350 years. Vertical distributions of the contaminants correlate with changes in the nature of watershed/estuarine activities. All contaminants were highly enriched (tens to hundreds times background) in modern New Bedford Harbor sediments. Enrichment began around the turn of the 20th century for all but PCBs, which were first synthesized in the 1930s. An increase in organic carbon content and a shift of carbon isotopes toward a more terrestrial signature illustrates increasing anthropogenic impact in New Bedford as population grew along with the industrial base. Institution of environmental protection measures in the late 20th century was reflected in decreased, although still substantially elevated, concentrations of contaminants. A lack of industrial development in Apponagansett Bay resulted in much lower concentrations of the same indicators, although specific contaminants related to the early whaling industry increased significantly above background as early as the late 18th century. The similarity of indicators in older portions of cores from NBH and unimpacted Apponagansett Bay demonstrates that cores can be used to establish reference conditions as successfully as using separate sites judged a priori to represent the reference state. The historical reconstruction approach provides the basis for establishing relationships between environmental stressors and factors that drive the stressors, as well as a framework for the assessment of ecological response(s) to environmental stressors over a range of time and/or exposure scales.

Since pre-industrial times, anthropogenic emissions of Hg have at least doubled global atmospheric Hg deposition rates. In order to minimize environmental and human health effects, efforts have been made to reduce Hg emissions from industries and power plants, while less attention has been paid to Hg mining. This paper is a compilation of available data on primary Hg production and associated emissions with regional and annual resolution since colonial times. Globally, approximately one million tons of metallic Hg has been extracted from cinnabar and other ores during the past five centuries, half already before 1925. Roughly half has been used for mining of gold and silver, but the annual Hg production peaked during a short period of recent industrial uses. Comparison with total historic Hg deposition from global anthropogenic emissions (0.1-0.2 Mtons) suggests that only a few percent of all mined Hg have escaped to the atmosphere thus far. While production of primary Hg has changed dramatically over time and among mines, the global production has always been dominant in the region of the mercuriferous belt between the western Mediterranean and central Asia, but appears to be shifting to the east. Roughly half of the registered Hg has been extracted in Europe, where Spanish mines alone have contributed one third of the world's mined Hg. Approximately one fourth has been mined in the Americas, and most of the remaining registered Hg in Asia. However, the Asian figures may be largely underestimated. Presently, the dominant Hg mines are in Almadén in Spain (236 t of Hg produced in 2000), Khaydarkan in Kyrgyzstan (550 t), Algeria (estimated 240 t) and China (ca. 200 t). Mercury by-production from mining of other metals (e.g. copper, zinc, gold, silver) in 2000 includes 48 t from Peru, 45 t from Finland and at least 15 t from the USA. Since 1970, the recorded production of primary Hg has been reduced by almost an order of magnitude to approximately 2000 t in the year 2000. Mining is thus still of similar magnitude as all current anthropogenic Hg emissions to the atmosphere, and mined Hg may account for more than one third of these emissions. Also before use, mercury is emitted from Hg mines locally during the mining and refining processes and from mining waste. Global direct emissions to the atmosphere amount to 10-30 t per year currently (up to 10 at Almadén alone), and probably exceed 10000 t historically. Termination of Hg mining will reduce associated local emissions to the atmosphere and biosphere. Since several economically viable Hg-free alternatives exist for practically all applications of Hg, the production and use of Hg can be further reduced and all primary production of Hg other than by-production terminated.