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1.
Sci Rep ; 10(1): 10974, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620909

RESUMO

Bioactive metal releases in ocean surface water, such as those by ash falls during volcanic super-eruptions, might have a potentially toxic impact on biocalcifier planktic microorganisms. Nano-XRF imaging with the cutting-edge synchrotron hard X-ray nano-analysis ID16B beamline (ESRF) revealed for the first time a specific Zn- and Mn-rich banding pattern in the test walls of Globorotalia menardii planktic foraminifers extracted from the Young Toba Tuff layer, and thus contemporaneous with Toba's super-eruption, 74,000 years ago. The intra-test correlation of Zn and Mn patterns at the nanoscale with the layered calcareous microarchitecture, indicates that the incorporation of these metals is syngenetic to the wall growth. The preferential Mn and Zn sequestration within the incipient stages of chamber formation suggests a selective incorporation mechanism providing a resilience strategy to metal pollution in the test building of planktic foraminifers.


Assuntos
Foraminíferos/metabolismo , Oligoelementos/metabolismo , Erupções Vulcânicas , Animais , Cálcio/metabolismo , Parede Celular/metabolismo , Parede Celular/ultraestrutura , Poluentes Ambientais/metabolismo , Foraminíferos/ultraestrutura , Fósseis/história , Fósseis/ultraestrutura , Sedimentos Geológicos/química , História Antiga , Oceano Índico , Nanopartículas Metálicas/química , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Síncrotrons , Erupções Vulcânicas/análise , Erupções Vulcânicas/história , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/história , Zooplâncton/metabolismo , Zooplâncton/ultraestrutura
2.
Ecotoxicol Environ Saf ; 196: 110542, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32276160

RESUMO

Historical residual of persistent organic pollutants (POPs) in flood sediment from a karst cave were investigated. Fifteen vertical sediment samples were collected from a 6 m-deep flood sediment profile in the Longwang Cave, and the concentrations of organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs) and particle size distribution in the sediments were analysed. The concentrations of OCPs and PAHs varied from 0.85 ng g-1 to 63.1 ng g-1 (mean 8.11 ng g-1) and 5.05 ng g-1 to 82.6 ng g-1 (mean 13.9 ng g-1), respectively; major PAHs in the profile were 2- and 3-ringed PAHs and a few were 5- or 6- ringed PAHs, which indicated less influence from industry but a high impact from the local combustion of coal and biomass; HCHs and DDTs in the profile were historically residual in this region, and HCHs mainly originated from the application of Lindane, while DDTs originated from the application of dicofol and technical DDTs; no significant correlation between the concentrations of OCPs and PAHs and the sedimental particle size in the sediments was found.


Assuntos
Hidrocarbonetos Clorados/história , Resíduos de Praguicidas/história , Hidrocarbonetos Policíclicos Aromáticos/história , Poluentes Químicos da Água/história , Cavernas , China , Inundações , Sedimentos Geológicos/química , História do Século XX , Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise
3.
Nat Commun ; 11(1): 355, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953430

RESUMO

Global fish production (capture and aquaculture) has increased quickly, which has altered global flows of phosphorus (P). Here we show that in 2016, [Formula: see text] Tg P yr-1 (mean and interquartile range) was applied in aquaculture to increase fish production; while [Formula: see text] Tg P yr-1 was removed from aquatic systems by fish harvesting. Between 1950 and 1986, P from fish production went from aquatic towards the land-human systems. This landward P peaked at 0.54 Tg P yr-1, representing a large but overlooked P flux that might benefit land activities under P scarcity. After 1986, the landward P flux decreased significantly, and became negative around 2004, meaning that humans spend more P to produce fish than harvest P in fish capture. An idealized pathway to return to the balanced anthropogenic P flow would require the mean phosphorus use efficiency (the ratio of harvested to input P) of aquaculture to be increased from a current value of 20% to at least 48% by 2050 - a big challenge.


Assuntos
Produtos Agrícolas , Pesqueiros , Fósforo , Poluentes Químicos da Água/análise , Animais , Bases de Dados Factuais , Ecologia , Peixes , Água Doce/química , História do Século XX , História do Século XXI , Humanos , Alimentos Marinhos , Poluentes Químicos da Água/história
4.
Environ Toxicol Chem ; 39(1): 48-59, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31880839

RESUMO

Many metals (aluminum, cadmium, cobalt, copper, nickel, lead, zinc) are widely studied environmental contaminants because of their ubiquity, potential toxicity to aquatic life, and tendency for toxicity to vary widely as a function of water chemistry. The interactions between metal and water chemistry influence metal "bioavailability," an index of the rate and extent to which the metal reaches the site of toxic action. The implications of metal bioavailability for ecological risk assessment are large, with as much as a 100-fold variability across a range of water chemistries in surface waters. Beginning as early as the 1930s, considerable research effort was expended toward documenting and understanding metal bioavailability as a function of total and dissolved metal, water hardness, natural organic matter, pH, and other water characteristics. The understanding of these factors and improvements in both analytical and computational chemistry led to the development of modeling approaches intended to describe and predict the relationship between water chemistry and metal toxicity, including the free ion activity model, the gill surface interaction model, the biotic ligand model, and additional derivatives and regression models that arose from similar knowledge. The arc of these scientific advances can also be traced through the evolution of the US Environmental Protection Agency's ambient water quality criteria over the last 50 yr, from guidance in the "Green Book" (1968) to metal-specific criteria produced in the last decade. Through time, water quality criteria in many jurisdictions have incorporated increasingly sophisticated means of addressing metal bioavailability. The present review discusses the history of scientific understanding of metal bioavailability and the development and application of models to incorporate this knowledge into regulatory practice. Environ Toxicol Chem 2019;39:48-59. © 2019 SETAC.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Monitoramento Ambiental/métodos , Água Doce/química , Metais/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Organismos Aquáticos/metabolismo , Disponibilidade Biológica , Congressos como Assunto , Monitoramento Ambiental/história , Brânquias/química , Brânquias/metabolismo , História do Século XX , História do Século XXI , Ligantes , Metais/história , Modelos Biológicos , Poluentes Químicos da Água/história , Qualidade da Água
5.
Artigo em Inglês | MEDLINE | ID: mdl-31653046

RESUMO

Sediment cores were collected from four outlets in the Pearl River Estuary (Guangdong Province, China) and dated using the 210Pb method to investigate the pollution history of the area due to its relatively stable sedimentation status and hydrographic conditions in recent decades. The ages of the sediment cores were dated over 40 years (1968-2015). The concentrations at the four outlets ranged from 2.21 to 48.52 ng g-1 dw for nonylphenol and were non-detectable for 23.64 ng g-1 dw for bisphenol A (BPA), which exhibited a decreasing trend from north to south as well as seaward. The fluxes (2.84 to 112.91 ng cm-2 yr-1 and non-detectable to 59.33 ng cm-2 yr-1 for nonylphenol and bisphenol A, respectively) stabilized in the 1980s to 1990s due to the construction of sewage treatment systems. The fluxes increased again in the 21st century, which reached a peak ca. 2010 but declined in recent years due to the establishment of regulations and the decreasing number of industrial enterprises. Fluctuations in the pollution composition coincided with industrial development and governmental policies.


Assuntos
Compostos Benzidrílicos/análise , Poluição Ambiental/história , Estuários , Sedimentos Geológicos/química , Fenóis/análise , Rios/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/história , China , Monitoramento Ambiental/métodos , Poluição Ambiental/estatística & dados numéricos , História do Século XX , História do Século XXI
6.
Mar Pollut Bull ; 145: 396-406, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590802

RESUMO

We determined depth profiles of total mercury (T-Hg) in six 210Pb-dated sediment cores from Todos os Santos Bay to reconstruct the history of anthropogenic Hg accumulation. We also assessed superficial sediments samples from five estuaries. T-Hg concentrations (5-3500 µg kg-1) presented a large spatial and temporal variability. T-Hg concentrations in Ribeira Bay increased up to 200-fold along time, whereas the fluxes of T-Hg are substantially higher (up to 10,000 fold) than present-day wet deposition for industrialized areas. Sedimentary records indicate that a chlor-alkali plant has been the main source of Hg pollution until the present, although the T-Hg records suggest that harbor, shrimp farming, and oil refinery activities, besides Hg atmospheric depositions, are important across the bay. Sediments in the Ribeira Bay act as an important Hg sink. If sediments are eroded or disturbed, they may release Hg, thus posing a serious risk to wildlife and ecosystem health. CAPSULE: Sedimentary cores provide data on preindustrial levels and also anthropogenic fluxes of Hg for the appraisal of the magnitude, processes and potential risks of the contamination.


Assuntos
Sedimentos Geológicos , Atividades Humanas/história , Mercúrio/análise , Poluentes Químicos da Água/história , Baías , Brasil , Ecossistema , Monitoramento Ambiental , Poluição Ambiental/história , História do Século XX , História do Século XXI , Humanos , Poluentes Químicos da Água/análise
7.
Environ Monit Assess ; 191(4): 256, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30923917

RESUMO

This study presents results of a sediment core located in Coroa de Boi Bay, a not dredged cove within Patos Estuary, Southern Brazil. The distribution of metals (Hg, Cu, Pb) and U in the sediment profile records several contamination events since pre-colonial times to present days. A joint assessment of the distribution of these parameters and the consultation to historical documents allowed us to establish causal links between concentrations anomalies in the sediments and ancient anthropogenic contamination in the area. During the industrial period, sedimentation rates in the bay ranged from 3.4 to 5.5 mm year-1. Applying a sedimentation rate previously calculated for undisturbed sediments in the Patos Estuary, we trace the beginning of Hg contamination as having started in the colonial period in Southern Brazil, soon after a Hispanic-Lusitanian conflict situation in South America. The most probable source of Hg contamination during this period was carroting technology used in fur processing.


Assuntos
Colonialismo/história , Poluição Ambiental/história , Sedimentos Geológicos/química , Indústrias/história , Mercúrio/história , Poluentes Químicos da Água/história , Pelo Animal , Animais , Brasil , Monitoramento Ambiental/métodos , Estuários , História do Século XVIII , Mercúrio/análise , Metais Pesados/análise , Metais Pesados/história , Poluentes Químicos da Água/análise
8.
Mar Pollut Bull ; 136: 394-400, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30509822

RESUMO

China's rapid economic and social development has led to an acceleration in nutrient inputs to coastal waters, which, in turn, has resulted in severe coastal eutrophication. On the occasion of the 40th anniversary of China's reform and opening up, the evolution of the causative factors and the state as well as future prospects for coastal eutrophication in the China Seas are analyzed and summarized. Results showed that the coastal eutrophication situation was not so serious at the beginning of reform and opening up, but it worsened rapidly from the end of the 1980s to the mid-2000s. In the last decade, the worsening trend has been curbed but the status of coastal eutrophication has not been substantially improved. Much work is still needed to be able control the total amount of nutrients entering coastal waters and enable comprehensive treatment of coastal eutrophication in the China Seas.


Assuntos
Monitoramento Ambiental/métodos , Eutrofização , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental/história , História do Século XX , História do Século XXI , Nitrogênio/análise , Oceanos e Mares , Fósforo/análise , Prognóstico , Poluentes Químicos da Água/história
9.
Artigo em Inglês | MEDLINE | ID: mdl-30082664

RESUMO

In France, 95% of people are supplied with chlorinated tap water. Due to the presence of natural organic matter that reacts with chlorine, the concentrations of chlorination by-products (CBPs) are much higher in chlorinated water produced from surface water than from groundwater. Surface water supplies 33% of the French population. Until the 1980s, almost all surface water utilities pre-chlorinated water at the intake. Pre-chlorination was then gradually banned from 1980 to 2000. Trihalomethanes (THMs) are the only regulated CBP in France. Since 2003, THMs have been monitored at the outlet of all utilities. This study assessed current (2005⁻2011) and past (1960⁻2000) exposure of the French population to THMs. We developed an original method to model THM concentrations between 1960 and 2000 according to current concentrations of THMs, concentration of total organic carbon in raw and finished water, and the evolution of water treatments from 1960 onward. Current and past mean exposure of the French population to THMs was estimated at 11.7 µg·L-1 and 17.3 µg·L-1, respectively. In the past, approximately 10% of the French population was exposed to concentrations >50 µg·L-1 vs. 1% currently. Large variations in exposure were observed among France's 100 administrative districts, mainly depending on the water origin (i.e., surface vs. ground), ranging between 0.2 and 122.1 µg·L-1 versus between 1.8 and 38.6 µg·L-1 currently.


Assuntos
Água Potável/análise , Monitoramento Ambiental/métodos , Trialometanos/história , Poluentes Químicos da Água/história , França , Halogenação , História do Século XX , História do Século XXI , Modelos Teóricos , Trialometanos/análise , Poluentes Químicos da Água/análise , Purificação da Água/história , Purificação da Água/métodos
10.
Water Res ; 139: 108-117, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29631186

RESUMO

Over the last century, nutrient concentrations in streams, rivers, lakes and ponds have increased substantially in the United States. Elevated phosphorus levels are a concern due to their ability to cause changes in freshwater ecosystems that are detrimental to humans and wildlife. In the present study, long-term trends in total phosphorus (TP) concentrations from 20 rivers in central Massachusetts from 1999 to 2013 were investigated. Kendall's correlation coefficients were used to demonstrate that 18 of the 20 rivers had significant reductions in TP concentrations (P < 0.05). A similar trend was found when flow-adjusted TP concentrations were analyzed. At the beginning of monitoring activities, the average TP concentration in 9 of the 20 rivers was greater than 0.05 mg/L and 6 of these 9 rivers contained TP concentrations greater than 0.1 mg/L; about fifteen years later, only 3 rivers contained TP greater than 0.05 mg/L and none had concentrations> 0.1 mg/L. TP decreases were greater in rivers with more anthropogenic inputs. Principal component analysis (PCA) revealed that the decline of TP in these Massachusetts streams is likely the result of advancements in wastewater treatment and implementation of effective non-point source management practices.


Assuntos
Fósforo/análise , Rios/química , Poluentes Químicos da Água/análise , Conservação dos Recursos Naturais , Monitoramento Ambiental/estatística & dados numéricos , História do Século XX , História do Século XXI , Massachusetts , Fósforo/história , Poluentes Químicos da Água/história
11.
Mar Pollut Bull ; 125(1-2): 459-471, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28800910

RESUMO

The evolution of the impacts of anthropogenic activities in Todos os Santos Bay was evaluated by profiles of trace metals and Pb isotopes determined in sediment cores. Fluxes of metals increased up to 12, 4 and 2 times for Cu, Pb, and Zn, respectively, compared to those recorded in the beginning of the 20th century. Stable Pb isotopes identified a decommissioned lead smelter and burning of fossil fuels as the main sources of Pb. Most metals showed minor to moderate enrichment factors (EF<4), but Cu and Pb were highly enriched (EF=28 and 6, respectively) at the Aratu harbor. Temporal changes in sediments were associated to different activities, namely Pb smelting, burning of fossil fuels, maritime traffic, petroleum related activities, inputs of domestic effluents, and changes in land uses. The effects of the implementation of environmental policies to improve the waters of the bay could not be identified in the evaluated cores.


Assuntos
Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Baías , Brasil , Monitoramento Ambiental/história , História do Século XIX , História do Século XX , História do Século XXI , Atividades Humanas , Humanos , Isótopos , Metais Pesados/história , Poluentes Químicos da Água/história
12.
Clin Toxicol (Phila) ; 55(8): 934-938, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28594236

RESUMO

The methylmercury contamination of Minamata Bay during the WWII postwar period resulted in thousands of Japanese citizens suffering horrific neurological injury. Fear and miscommunication destroyed and changed family and social structure. In addition, the Minamata poisoning caused momentous changes in the civic discourse in Japan and was an instrumental event in the democratization of the country. This manuscript describes the effects that the environmental contamination and human poising had in the transition of Japan from a feudal society to a democratic one.


Assuntos
Indústria Química , Exposição Ambiental/efeitos adversos , Intoxicação do Sistema Nervoso por Mercúrio/epidemiologia , Compostos de Metilmercúrio/intoxicação , Sistema Nervoso/efeitos dos fármacos , Poluentes Químicos da Água/intoxicação , Indústria Química/história , Indústria Química/legislação & jurisprudência , Democracia , Exposição Ambiental/história , Monitoramento Ambiental , História do Século XX , Humanos , Japão/epidemiologia , Intoxicação do Sistema Nervoso por Mercúrio/diagnóstico , Intoxicação do Sistema Nervoso por Mercúrio/história , Intoxicação do Sistema Nervoso por Mercúrio/fisiopatologia , Compostos de Metilmercúrio/história , Sistema Nervoso/fisiopatologia , Formulação de Políticas , Prognóstico , Política Pública , Fatores de Tempo , Poluentes Químicos da Água/história
13.
Environ Health ; 16(1): 61, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28641573

RESUMO

BACKGROUND: Polycyclic aromatic hydrocarbons (PAHs) are the main toxic compounds in natural bitumen, a fossil material used by modern and ancient societies around the world. The adverse health effects of PAHs on modern humans are well established, but their health impacts on past populations are unclear. It has previously been suggested that a prehistoric health decline among the native people living on the California Channel Islands may have been related to PAH exposure. Here, we assess the potential health risks of PAH exposure from the use and manufacture of bitumen-coated water bottles by ancient California Indian societies. METHODS: We replicated prehistoric bitumen-coated water bottles with traditional materials and techniques of California Indians, based on ethnographic and archaeological evidence. In order to estimate PAH exposure related to water bottle manufacture and use, we conducted controlled experiments to measure PAH contamination 1) in air during the manufacturing process and 2) in water and olive oil stored in a completed bottle for varying periods of time. Samples were analyzed with gas chromatography/mass spectrometry (GC/MS) for concentrations of the 16 PAHs identified by the US Environmental Protection Agency (EPA) as priority pollutants. RESULTS: Eight PAHs were detected in concentrations of 1-10 µg/m3 in air during bottle production and 50-900 ng/L in water after 2 months of storage, ranging from two-ring (naphthalene and methylnaphthalene) to four-ring (fluoranthene) molecules. All 16 PAHs analyzed were detected in olive oil after 2 days (2 to 35 µg/kg), 2 weeks (3 to 66 µg/kg), and 2 months (5 to 140 µg/kg) of storage. CONCLUSIONS: For ancient California Indians, water stored in bitumen-coated water bottles was not a significant source of PAH exposure, but production of such bottles could have resulted in harmful airborne PAH exposure.


Assuntos
Poluentes Atmosféricos/história , Água Potável/análise , Exposição Ambiental/história , Hidrocarbonetos , Hidrocarbonetos Policíclicos Aromáticos/história , Grupos Populacionais/história , Poluentes Químicos da Água/história , Poluentes Atmosféricos/análise , California , Exposição Ambiental/análise , História Antiga , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Poluentes Químicos da Água/análise
14.
Environ Pollut ; 224: 70-81, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28284543

RESUMO

Reconstructing historical sedimentary records is essential for better understanding the effects of anthropogenic activities on river environments. We used lead-210 to date riverine sediment core from the Shima River in China. We obtained a sedimentary history of 34 years (1982-2015) for core S2, which had a length of 34 cm. The sedimentation rate of 0.304-2.04 cm y-1 was controlled by both flood events and anthropogenic activities. The conservative element content depth profiles remained relatively constant, suggestive of a relatively stable sediment provenance; therefore, the increase in the sedimentation rate over time was mainly the result of domestic and industrial wastewater effluent and the construction of a rubber dam at the middle and lower reach of the Shima River. From 1982 to 2015, the nutrient and trace metal depth profiles could be divided in three periods based on their trends. From 1982 to 1993, the vertical profiles of nutrients (organic carbon, total phosphorus, and total nitrogen) and three trace metals (nickel, zinc, and manganese) were relatively stable; however, the gradual decrease in copper and cadmium was likely associated with a reduction in agricultural chemical application. From 1993 to 2003, a population explosion and rapid industrialization were responsible for an increase in the input of pollutants into the Shima River, which was partly attenuated by water from the Dong River, leading to a gradual increase in nutrient and trace metal contents. Finally, from 2003 to 2015, the Shima River stopped being used as a source of water due to its deteriorating water quality. The relatively lower velocity of the water flow after the recovery of its flow direction and the reconstruction of the rubber dam in 2009 provided advantageous sedimentary conditions, promoting nutrient accumulation and significant trace metal enrichment.


Assuntos
Sedimentos Geológicos/química , Rios/química , Agricultura , Cádmio/análise , China , Monitoramento Ambiental , História do Século XX , História do Século XXI , Nitrogênio/análise , Fósforo/análise , Tempo , Oligoelementos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/história , Qualidade da Água
15.
Mar Pollut Bull ; 114(2): 816-820, 2017 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-27847168

RESUMO

Buccinanops globulosus is a TBT sensitive marine gastropod, classified as a good indicator of imposex incidence and used as a model to study adverse contamination effects. Population and maritime industries has incremented pollution in Nuevo gulf harbor since 1970s, promoting morphological changes in B. globulosus shell shape. We study the shell shape of the species comparing present day's specimens from the harbor zone with those collected in the same zone before the increasing of maritime activity and pre-Hispanic archaeological Middens. We demonstrated that harbor pollution produces globular shell shape in B. globulosus, an effect that probably allows gastropods to isolate themselves from the external adverse environment. On the contrary, shells from pre-Hispanic periods, unpolluted sites and those collected before the expansion of maritime activities, presented an elongated shell shape. Our study confirms that shell shape variation in marine gastropods can be used as a biomarker of harbor pollution.


Assuntos
Monitoramento Ambiental/métodos , Gastrópodes/efeitos dos fármacos , Compostos de Trialquitina/análise , Poluentes Químicos da Água/análise , Animais , Argentina , Biomarcadores , Tamanho Corporal , Monitoramento Ambiental/história , Gastrópodes/crescimento & desenvolvimento , Gastrópodes/fisiologia , História do Século XX , História do Século XXI , Reprodução/efeitos dos fármacos , Compostos de Trialquitina/história , Compostos de Trialquitina/toxicidade , Poluentes Químicos da Água/história , Poluentes Químicos da Água/toxicidade
16.
Environ Sci Pollut Res Int ; 23(12): 11598-610, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26931663

RESUMO

This paper reports the reconstruction of the pollution history of 4-tert-octylphenol (OP) and 4-nonylphenol (NP) in the Baltic Sea. Alkylphenols are endocrine-disrupting compound and therefore toxic to aquatic organisms. Sediment cores were collected from regions with relatively stable sedimentation conditions. The cores were dated by the (210)Pb method. The OP and NP were determined using HPLC-FL. The highest inventory of these compounds was observed in the Gotland Deep (610 µg m(2) of NP and 47 µg m(2) of OP) and the lowest-on the slope of the Gdansk Deep (24 µg m(2) of NP and 16 µg m(2) of OP). Such spatial distribution was probably, among other factors, the result of the uplift of the sea floor. The pollution trends of OP and NP in sediments coincided with the following: (1) the beginnings of eutrophication (1960s/1970s of the twentieth century) and (2) strong increase in the areal extent and volume of hypoxia and anoxia in the Baltic (present century).


Assuntos
Fenóis/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , História do Século XX , História do Século XXI , Radioisótopos de Chumbo , Oceanos e Mares , Fenóis/história , Poluentes Químicos da Água/história
18.
Chemosphere ; 144: 1815-22, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26539705

RESUMO

Information on historical deposition of persistent organic pollutants (POPs) for African lakes is very limited. We investigated historical deposition trends and sources of POPs in sediment cores from Lakes Victoria (SC1), Bujuku (Buju2) and Mahoma (Maho2). The latter two lakes are situated in the Rwenzori mountain range in western Uganda. SC1 was taken from a central depositional area within the Ugandan part of the lake. Profiles in Buju2 and Maho2 were used as a reference for historical atmospheric deposition. For the post-1940 sediment deposits in SC1, average focusing factor-adjusted fluxes (FFFs) of ΣDDTs, polychlorinated biphenyls (ΣPCBs), hexachlorocyclohexanes (ΣHCHs) and chlordanes (ΣCHLs) were 390, 230, 210 and 120 ng m(-2) yr(-1). Higher fluxes of ΣDDTs, ΣPCBs, and ΣCHLs were observed in Buju2 and Maho2. The average FFF of HCB in Buju2 was the highest while the values for Maho2 and SC1 were similar. The endosulfan FFFs in SC1 were lower than in the alpine lake cores. Generally, Buju2 was a better reference for historical atmospheric deposition of POPs than Maho2 probably due to distortion of the latter's profile by Lake Mahoma's forested catchment. Profiles of p,p'-DDE, ΣCHLs and HCB in SC1 were consistent with atmospheric deposition while profiles of PCBs and HCHs were indicative of particle-bound loadings from additional sources. Profiles of endosulfans, DDTs, and chlordanes were consistent with influence of other factors such as anoxia, and dilution. Further studies of spatial resolution of historical deposition, especially in near-shore deposition areas of the lake are recommended.


Assuntos
Endossulfano/análise , Hidrocarbonetos Clorados/análise , Lagos/análise , Poluentes Químicos da Água/análise , África Oriental , Endossulfano/história , Monitoramento Ambiental/história , História do Século XX , História do Século XXI , Hidrocarbonetos Clorados/história , Poluentes Químicos da Água/história
19.
Environ Monit Assess ; 187(9): 594, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26311263

RESUMO

Sydney estuary has a long history of environmental degradation and is one of the most modified water ways in Australia due to a highly urbanised catchment (~77 %) and a high population (4.6 million). The objectives of the present study were to map historical land use change from European settlement (1788) to 2010 to determine catchment evolutionary pathways and to estimate catchment loading (total suspended solids, Cu, Pb and Zn) to the estuary over this period. Land use distribution in Sydney catchment, determined for seven time horizons over this period, indicated that a substantial increase in residential land use through subdivision of large estates and an increase in road area resulted in a marked increase in metal loading to Sydney estuary between 1892 and 1936. The decline in industrial activity from a maximum in 1978 (3.9 %) to 1.8 % in 2010 and the introduction of unleaded fuel during this time was accompanied by reduction in metal loading to the estuary. Land use time horizon maps enabled the creation of novel, ternary diagrams to represent temporal evolution in catchment land use. The 15 sub-catchments of Sydney estuary were combined into three major catchment categories, i.e., urban, dense urban and commercial. Present-day annual discharge of stormwater from the Sydney catchment was calculated to be 466,000 ML and annual loadings of total suspended sediment (TSS), Cu, Pb and Zn in tonnes were 49,239, 27, 37 and 57, respectively. Stormwater has superseded industry as the main source of anthropogenic metals to this estuary in recent times.


Assuntos
Cidades , Monitoramento Ambiental/estatística & dados numéricos , Estuários , Atividades Humanas/história , Metais Pesados/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/história , Monitoramento Ambiental/métodos , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , New South Wales
20.
Chemosphere ; 119: 961-970, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25303655

RESUMO

Hydrocarbon contaminants are ubiquitous in urban aquatic ecosystems, and the ability of some microbial strains to degrade certain polycyclic aromatic hydrocarbons (PAHs) is well established. However, detrimental effects of petroleum hydrocarbon contamination on nondegrader microbial populations and photosynthetic organisms have not often been considered. In the current study, fatty acid methyl ester (FAME) biomarkers in the sediment record were used to assess historical impacts of petroleum contamination on microbial and/or algal biomass in South San Francisco Bay, CA, USA. Profiles of saturated, branched, and monounsaturated fatty acids had similar concentrations and patterns downcore. Total PAHs in a sediment core were on average greater than 20× higher above ∼200 cm than below, which corresponds roughly to the year 1900. Isomer ratios were consistent with a predominant petroleum combustion source for PAHs. Several individual PAHs exceeded sediment quality screening values. Negative correlations between petroleum contaminants and microbial and algal biomarkers - along with high trans/cis ratios of unsaturated FA, and principle component analysis of the PAH and fatty acid records - suggest a negative impacts of petroleum contamination, appearing early in the 20th century, on microbial and/or algal ecology at the site.


Assuntos
Ácidos Graxos/análise , Sedimentos Geológicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Microbiologia da Água , Poluentes Químicos da Água/análise , Baías , Biomarcadores/análise , Biomassa , Monitoramento Ambiental , Ésteres , História do Século XX , Petróleo , Hidrocarbonetos Policíclicos Aromáticos/história , São Francisco , Poluentes Químicos da Água/história
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