Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Sci Total Environ ; 917: 170563, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38296082

RESUMO

Lake Maggiore has been the subject of a monitoring program on persistent organic pollutants (DDTs and PCBs) since 1996 when DDT contamination was first detected. In this context, in 2009 we started to estimate the concentration of DDTtot (Dichlorodiphenyltrichloroethane, sum of p,p'-DDT, o,p'-DDT, p,p'-DDD, o,p-DDD, p,p-DDE, o,p-DDE) and sumPCB14 (polychlorinated biphenyls 18, 28, 31, 44, 52, 101, 118, 149, 138, 153, 170, 180, 194 and 209) in zooplankton pelagic organisms preyed on by zooplanktivorous fish (size fraction ≥450 µm). We evaluated taxa specific repositories of DDTtot and sumPCB14, their seasonal variation, their changes over the period 2009-2021 and the potential contribution of different taxa in transferring toxicants to whitefish, based on the Ivlev's Electivity Index. The repository of both POPs was generally higher in spring. A decrease in the zooplankton Standing Stock Biomass (SSB) drove a decline in the zooplankton DDTtot repository over the last six years (2016-2021 SSBmean = 12.5 mg m-3; 2009-2015; SSBmean = 30 mg m-3), despite the concentration being broadly constant during this period. The sumPCB14 repository was generally characterized by lower values during the last six years, but the difference with the previous period was not so marked. Daphnia and cyclopoids were the major contributors to the repository; however, when the whitefish selectivity index was applied, the role of carnivorous Bythotrephes was more important to the detriment of cyclopoids, particularly in summer and winter. Our results are useful to elaborate predictive models on the transfer of POPs along the food chain and highlight not only the importance of freshwater zooplankton in toto, but also that different taxa can have different roles. The increasing importance of microphagous zooplankton, driven by water warming and extended thermal stratification, underlines the need for future studies on the role of small zooplankton as carriers of POPs in freshwater lakes.


Assuntos
Bifenilos Policlorados , Salmonidae , Animais , DDT/análise , Lagos , Zooplâncton , Estações do Ano , Monitoramento Ambiental , Bifenilos Policlorados/análise , Diclorodifenil Dicloroetileno/análise
2.
Toxics ; 11(12)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38133418

RESUMO

Lakes are essentially interlinked to humans as they provide water for drinking, agriculture, industrial and domestic purposes. The upsurge of plastic usage, its persistence, and potential detrimental effects on organisms cause impacts on the trophic food web of freshwater ecosystems; this issue, however, still needs to be explored. Zooplankton worldwide is commonly studied as an indicator of environmental risk in aquatic ecosystems for several pollutants. The aim of the review is to link the existing knowledge of microplastic pollution in zooplankton to assess the potential risks linked to these organisms which are at the first level of the lacustrine trophic web. A database search was conducted through the main databases to gather the relevant literature over the course of time. The sensitivity of zooplankton organisms is evident from laboratory studies, whereas several knowledge gaps exist in the understanding of mechanisms causing toxicity. This review also highlights insufficient data on field studies hampering the understanding of the pollution extent in lakes, as well as unclear trends on ecosystem-level cascading effects of microplastics (MPs) and mechanisms of toxicity (especially in combination with other pollutants). Therefore, this review provides insight into understanding the overlooked issues of microplastic in lake ecosystems to gain an accurate ecological risk assessment.

3.
J Hazard Mater ; 452: 131330, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37004438

RESUMO

The interaction between environmental plastic and trace elements is an issue of concern. Understanding their interaction mechanisms is key to evaluate the potential threats for the environment. To this regard, consolidating confidence in extraction protocols can help in understanding the amount of different species present on plastic surface, as well as the potential mobility of trace elements present inside the plastic matrix (e.g., additives). Here we tested the efficacy of different reagents to mimic the elemental phases bonded to meso- and microplastic in the environment, in relation to the grade of ageing and the polymer composition. Results showed that a relatively high portion of trace elements is bonded in a weak phase and that other phases abundant in other matrices (e.g., oxides and bonded to organic matter) are only present to a limited degree in the plastic samples. The comparison of different sample types highlighted the important role of plastic ageing in governing interactions with trace elements, while the polymer composition has a limited influence on this process. Finally, the future steps toward a tailored extraction scheme for environmental plastic are proposed.

4.
Sci Total Environ ; 857(Pt 2): 159379, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36228801

RESUMO

Determining the concentration of POPs (Persistent Organic Pollutants) such as total dichlorodiphenyltrichloroethane (DDTtot) and polychlorinated biphenyls (PCBs) in the zooplankton is essential for evaluating the level of toxicity in the environment and the risk to ecosystem health. The extent to which POPs persist in the environment and affect human health depends on accumulation in the different components of the zooplankton community such as particle feeders and/or predators and their subsequent consumption by fish, which varies seasonally. We analyzed ten-years (2011-2020) of seasonal data on POPs in the crustacean zooplankton community of Lake Maggiore (Italy). The concentration of total DDTs, as sum of all congeners ranged between 23.5 and 156.9 ng/g dry weight, while sumPCB14 ranged from 24.4 and 133.6 ng/g dry weight. We traced particle feeders' vs predatory taxa within the zooplankton community using carbon and nitrogen stable isotopic values. POPs concentration was significantly related to the nitrogen isotopic values. The zooplankton biomass increase in Spring was important, both through this being a period of increased metabolism and activity of planktivorous fish and also as it was the period when the zooplankton repository of POPs was at a maximum. DDTtot stocked in zooplankton ≥450 µm was up to 275 ng/m2, while sumPCB14 was 285 ng/m2 in 2013. A decrease of DDTtot stocked in the zooplankton repository characterized the last five years examined, when mean annual values (14.8-56.9 ng/m2) were less than half those of the previous period (50.7-128.6 ng/m2).


Assuntos
Bifenilos Policlorados , Poluentes Químicos da Água , Animais , Humanos , Zooplâncton/metabolismo , Lagos , DDT/análise , Estações do Ano , Ecossistema , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Bifenilos Policlorados/análise , Peixes/metabolismo , Isótopos de Nitrogênio
5.
Environ Sci Pollut Res Int ; 30(3): 6298-6312, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35994148

RESUMO

Pollution by plastic and microplastic impacts the environment globally. Knowledge on the ageing mechanisms of plastics in natural settings is needed to understand their environmental fate and their reactivity in the ecosystems. Accordingly, the study of ageing processes is gaining focus in the context of the environmental sciences. However, laboratory-based experimental research has typically assessed individual ageing processes, limiting environmental applicability. In this study, we propose a multi-tiered approach to study the environmental ageing of polyethylene plastic fragments focusing on the combined assessment of physical and biological processes in sequence. The ageing protocol included ultraviolet irradiation in air and in a range of water solutions, followed by a biofouling test. Changes in surface characteristics were assessed by Fourier transform infrared spectroscopy, scanning electron microscopy, and water contact angle. UV radiation both in air and water caused a significant increase in the density of oxidized groups (i.e., hydroxyl and carbonyl) on the plastic surface, whereby water solution chemistry influenced the process both by modulating surface oxidation and morphology. Biofouling, too, was a strong determinant of surface alterations, regardless of the prior irradiation treatments. All biofouled samples present (i) specific infrared bands of new surface functional groups (e.g., amides and polysaccharides), (ii) a further increase in hydroxyl and carbonyl groups, (iii) the diffuse presence of algal biofilm on the plastic surface, and (iv) a significant decrease in surface hydrophobicity. This suggests that biological-driven alterations are not affected by the level of physicochemical ageing and may represent, in real settings, the main driver of alteration of both weathered and pristine plastics. This work highlights the potentially pivotal role of biofouling as the main process of plastic ageing, providing useful technical insights for future experimental works. These results also confirm that a multi-tiered laboratory approach permits a realistic simulation of plastic environmental ageing in controlled conditions.


Assuntos
Plásticos , Poluentes Químicos da Água , Polietileno/análise , Ecossistema , Poluentes Químicos da Água/análise , Água , Monitoramento Ambiental
6.
Anal Chim Acta ; 1206: 339553, 2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35473882

RESUMO

A fast and cost-effective procedure based on Inductively Coupled Plasma - Mass Spectrometry (ICP-MS) for the selective determination of methylmercury (MeHg) is proposed and validated for fish tissue analysis. Selectivity for MeHg is achieved by simply inserting a strong anion exchange resin to block inorganic mercury as negatively charged chloride species, leaving MeHg unretained. The procedure features a 15 min extraction time followed by a 100 s analysis time achieving a limit of detection of 1.6 µg kg-1 on solid samples. The effect of the solution composition and inorganic mercury concentration were extensively studied to fully assess the selectivity of the procedure: Hg(II):MeHg ratios up to 50 are tolerated and cause systematic errors lower than 15%. The entire procedure was successfully validated by standard reference material from the marine food web, namely fish muscle and liver plus zooplankton. The method was finally applied to the detection of MeHg in the marine trophic web of Djibouti (Gulf of Aden): a trophic magnification factor of 13.5 proved the high risk associated with the biomagnification of methylmercury.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Animais , Peixes , Cadeia Alimentar , Mercúrio/análise , Compostos de Metilmercúrio/análise , Análise Espectral
7.
Sci Total Environ ; 824: 153756, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35151733

RESUMO

During the first period of the SARS-CoV-2 pandemic, the lack of specific therapeutic treatments led to the provisional use of a number of drugs, with a continuous review of health protocols when new scientific evidence emerged. The management of this emergency sanitary situation could not take care of the possible indirect adverse effects on the environment, such as the release of a large amount of pharmaceuticals from wastewater treatment plants. The massive use of drugs, which were never used so widely until then, implied new risks for the aquatic environment. In this study, a suspect screening approach using Liquid Chromatography-High Resolution Mass Spectrometry techniques, allowed us to survey the presence of pharmaceuticals used for COVID-19 treatment in three WWTPs of Lombardy region, where the first European cluster of SARS-CoV-2 cases was detected. Starting from a list of sixty-three suspect compounds used against COVID-19 (including some metabolites and transformation products), six compounds were fully identified and monitored together with other target analytes, mainly pharmaceuticals of common use. A monthly monitoring campaign was conducted in a WWTP from April to December 2020 and the temporal trends of some anti-COVID-19 drugs were positively correlated with those of COVID-19 cases and deaths. The comparison of the average emission loads among the three WWTPs evidenced that the highest loads of hydroxychloroquine, azithromycin and ciprofloxacin were measured in the WWTP which received the sewages from a hospital specializing in the treatment of COVID-19 patients. The monitoring of the receiving water bodies evidenced the presence of eight compounds of high ecological concern, whose risk was assessed in terms of toxicity and the possibility of inducing antibiotic and viral resistance. The results clearly showed that the enhanced, but not completely justified, use of ciprofloxacin and azithromycin represented a risk for antibiotic resistance in the aquatic ecosystems.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Poluentes Químicos da Água , Azitromicina/efeitos adversos , COVID-19/epidemiologia , Ciprofloxacina/análise , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Preparações Farmacêuticas , SARS-CoV-2 , Águas Residuárias/química , Poluentes Químicos da Água/análise
8.
Water Res ; 204: 117637, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34536685

RESUMO

Plastic and microplastic pollution is an environmental and societal concern. The interaction of plastic with organic chemicals in the environment has attracted scientific interest. New evidences have highlighted an unexpectedly high affinity of environmental plastics also for metal ions. The degree and typology of plastic ageing (including from mechanical, UV and biological degradations) appear as a pivotal factor determining such an interaction. These earlier evidences recently opened a new research avenue in the plastic pollution area. This review is the first to organize and critically discuss knowledge developed so far. Results from field and laboratory studies of metal accumulation on plastic are presented and the environmental factors most likely to control such an interaction are discussed. On the light of this knowledge, a generalist conceptual model useful for building hypotheses on the mechanisms at stake and directing future studies was elaborated and presented here. Furthermore, all available data on the thermodynamics of the plastic-metal interaction obtained from laboratory experiments are inventoried and discussed here, highlighting methodological and technical challenges that can potentially affect cross-comparability of data and their relevance for environmental settings. Finally, insights and recommendations on experimental approaches and analytical techniques that can help overtaking current limitations and knowledge gaps are proposed.


Assuntos
Oligoelementos , Poluentes Químicos da Água , Monitoramento Ambiental , Microplásticos , Plásticos , Água , Poluentes Químicos da Água/análise
9.
Environ Pollut ; 288: 117782, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34280746

RESUMO

Microplastic particles (MPs) contamination of aquatic environments has raised a growing concern in recent decades because of their numerous potential toxicological effects. Although fish are among the most studied aquatic organisms, reports on MPs ingestion in freshwater environments are still scarce. Thus, there is still much to study to understand the uptake mechanisms, their potential accumulation among the food webs and their ecotoxicological effects. Here, MPs presence in the digestive system of one of the most widespread and commercially exploited freshwater fish, the perch (Perca fluviatilis, Linnaeus 1758), was investigated in four different south-alpine lakes, to assess the extent of ingestion and evaluate its relation to the body health condition. A total of 80 perch specimen have been sampled from the Italian lakes Como, Garda, Maggiore and Orta. Microplastic particles occurred in 86% of the analysed specimens, with average values ranging from 1.24 ± 1.04 MPs fish-1 in L. Como to 5.59 ± 2.61 MPs fish-1 in L. Garda. The isolated particles were mainly fragments, except in L. Como where films were more abundant. The most common polymers were polyethylene, polyethylene terephthalate, polyamide, and polycarbonate, although a high degree of degradation was found in 43% of synthetic particles, not allowing their recognition up to a single polymer. Despite the high number of ingested MPs, fish health (evaluated by means of Fulton's body condition and hepatosomatic index) was not affected. Instead, fullness index showed an inverse linear relationship with the number of ingested particles, which suggests that also in perch MPs presence could interfere with feeding activity, as already described for other taxa.


Assuntos
Percas , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Itália , Lagos , Microplásticos , Plásticos , Poluentes Químicos da Água/análise
10.
Environ Toxicol Chem ; 40(3): 658-676, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32644251

RESUMO

Concentrations in fish of per- and polyfluoroalkyl substances (PFAS) were reported for 7 deep lakes in the European subalpine area: Lakes Geneva, Lugano, Maggiore, Iseo, Como, Garda, and Mergozzo; one shallow lowland lake (Varese); and 2 high-altitude alpine lakes (>2000 m a.s.l). Fillets and, in selected cases, other body fractions (viscera, liver, and residual carcass) from 8 fish species were analyzed. The possibility of harmonizing the monitoring protocols was tested. Results suggest that the sampling season is not critical for PFASs and the total protein content cannot be used for normalization of tissue concentrations because PFASs bind to specific proteins. Moreover, the polar lipid content could be used to reduce the variability of PFAS concentrations in phospholipid rich fractions of fish such as viscera and carcass. The data comparison and analysis show that the PFAS contamination in lake fish is generally correlated with the degree of urbanization of the lake catchment; however, it is sometimes difficult to compare absolute concentrations in lake fish because the lake hydro-morphological characteristics play a substantial role in determining the chemical concentrations of persistent and mobile contaminants. Environ Toxicol Chem 2021;40:658-676. © 2020 SETAC.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Peixes , Fluorocarbonos/análise , Lagos , Poluentes Químicos da Água/análise
11.
Anal Sci ; 36(7): 889-892, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32009020

RESUMO

In this paper, we proposed a high-throughput microwave digestion system based on multi-batch reactors (three quartz test tubes inside commercial PTFE vessels). This original configuration was validated by ICP-MS analysis of several elements in biological certified reference materials (fish tissues and plankton). The proposed system was proved to be free from contamination showing very low LODs. The improved hardware configuration is therefore highly beneficial for the detection of trace elements in microsamples from the marine food web.


Assuntos
Ensaios de Triagem em Larga Escala , Micro-Ondas , Oligoelementos/análise , Animais , Peixes , Espectrometria de Massas , Plâncton , Oligoelementos/metabolismo
12.
Sci Total Environ ; 653: 351-358, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30412880

RESUMO

Determination of 20 PFASs in a fish species (Alosa agone) of commercial interest has been carried out in five Italian subalpine lakes to assess the risk for humans and predators for fish consumption. PFOS still presents the highest concentrations (0.9-16.6ngg-1ww) among the analysed PFASs, in spite of its normative restrictions. PFOS concentrations measured in all lakes, except in Lake Maggiore, are homogeneous with an average of 3.1±1.9ngg-1ww, which could be considered the "anthropogenic background concentration" of PFOS in fish of lakes located in an industrialised and urbanised region but without point sources. In Lake Maggiore, fish concentrations always exceed the EU EQSbiota (9.1ngg-1ww) based on human fish consumption. Considering the effective consumption of fish in this area, an actual risk for fish consumption by humans is not evidenced, while a moderate risk of secondary poisoning for predators is highlighted. PFOA has been detected in significant concentration only in one sample in Lake Maggiore, while long chain PFCAs have been detected without significant differences among the lakes (0.3 to 2.7ngg-1ww). The present study demonstrates that biota monitoring of fish can be used as a valuable tool to classify the quality status of water bodies regarding bioaccumulative PFAAs, even if the water concentrations are close to the reachable detection limits.


Assuntos
Exposição Ambiental/análise , Peixes , Fluorocarbonos/análise , Contaminação de Alimentos/análise , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental , Humanos , Itália , Lagos , Medição de Risco
13.
Chemosphere ; 219: 54-57, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30529853

RESUMO

In this work we assessed the presence of two well-known pesticides (DDT and lindane) along with their main metabolite or isomer in tobacco products from 11 countries. In 11 of the 14 samples DDTs were the dominant compounds, with maximum concentrations of pp'-DDT in Morocco cigarettes (9 ng g-1) and of pp'-DDE in Italian cigars (13 ng g-1). Moreover, the α/γ-HCH ratio was mostly lower than 1, indicating the main use of "Lindane" formulation. However, all the detected levels were below the guidance residue values of respective pesticide and metabolite/isomer.


Assuntos
Hidrocarbonetos Clorados/análise , Nicotiana/química , Praguicidas/análise , Produtos do Tabaco/análise , DDT/análise , Hexaclorocicloexano/análise , Isomerismo
14.
Sci Total Environ ; 640-641: 98-106, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29859446

RESUMO

Despite DDT and PCB having been banned for about 40 years, they are still detectable in the environment. In the present research we specifically investigated the trophic transfer of these organochlorine contaminants (OC) through a pelagic food web of a deep lake in Northern Italy (Lake Como) over time. Zooplankton and fish were sampled each season of a year and OC concentrations and the carbon and nitrogen isotopic ratios were measured. By using stable isotopes, the direct trophic relationship between pelagic zooplankton and zooplanktivorous fish was confirmed for Alosa agone only in summer. Based on this result, the biomagnification factor normalized on the trophic level (BMFTL) for organic contaminants was calculated. BMFTL values were within the range 0.9-1.9 for DDT isomers and 1.6-4.9 for some PCB congeners (PCB 95, PCB 101, PCB 149, PCB 153, PCB 138 - present both in zooplankton and in fish and representing >60% of the PCB contamination), confirming the biomagnification of these compounds in one of the two zooplanktivorous fish species of the lake.


Assuntos
Monitoramento Ambiental , Cadeia Alimentar , Lagos/química , Compostos Orgânicos/análise , Poluentes Químicos da Água/análise , Animais , Peixes , Itália , Zooplâncton
15.
Sci Total Environ ; 613-614: 39-45, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28898810

RESUMO

Risk management of toxic substances is often based on Environmental Quality Standards (EQS) set for the water compartment, assuming they will also protect benthic organisms. In the absence of experimental data, EQS for sediments can be estimated by the equilibrium partitioning approach. The present study investigates whether this approach is protective of benthic organisms against pentachlorophenol (PCP), a legacy contaminant and EU priority substance still used in some parts of the world. Three freshwater species of invertebrates with different life cycles and feeding behaviors (the oligochaetes Lumbriculus variegatus, Tubifex tubifex and the dipteran insect Chironomus riparius) were exposed to PCP spiked sediments (2.10-46.03mgPCP/kg d.w. plus controls) in laboratory standard tests. Exposure duration was 28days for T. tubifex and L. variegatus and 10 and 28days for C. riparius; according to the corresponding OECD guidelines. For each investigated end-point, dose-response data were normalized to the mean control and fitted to a four-parameter log-logistic model for calculating the corresponding EC50 and EC10. The ranges for EC50 and EC10 estimates were 4.39 (Chironomus riparius-emergence)-27.50 (Tubifex tubifex-cocoon) and 0.30 (T. tubifex-young worms) -16.70 (T. tubifex-cocoon) mg/kg d.w., respectively. The EC50 and the EC10 values of L. variegatus were within these ranges. Following the EU Technical Guidance for deriving EQS, the lowest EC10 value of 0.30mg/kg (T. tubifex-young worms) resulted in a PCP quality standard (QS) for sediments of 30ng/g, about one fourth of the tentative QS of 119ng/g estimated by the equilibrium partitioning (EqP) approach. The response of benthic biota to PCP varied across organisms and across end-points for the same organism, so that the use of sediment PCP-QS calculated using the EqP-approach may be under-protective of the most sensitive organisms. Information on the possible effects of PCP on resident organisms must therefore be collected for appropriately managing aquatic systems.


Assuntos
Chironomidae/efeitos dos fármacos , Oligoquetos/efeitos dos fármacos , Pentaclorofenol/efeitos adversos , Poluentes Químicos da Água/efeitos adversos , Qualidade da Água/normas , Animais , União Europeia , Sedimentos Geológicos/química , Pentaclorofenol/normas , Poluentes Químicos da Água/normas
16.
Environ Res ; 156: 571-578, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28441638

RESUMO

BACKGROUND: Although banned in many countries for decades, DDTs and PCBs still represent a global threat to food safety. As these contaminants are still present in aquatic ecosystems, fish can be an important contributor to their total dietary intake. OBJECTIVES: Alosa agone specimens were sampled over a period of 10 years (from 2006 to 2015) to provide a representative overview of the DDT and PCB levels of Lago di Como, a deep Italian lake where a DDT input due to secondary sources was observed in recent years. The potential health risk from the consumption of both fresh and preserved fish was evaluated. RESULTS: While DDT levels have generally decreased during the monitored period, reaching quite stable levels, PCB concentrations were variable, with values exceeding, in some cases, the European Union limit for human consumption and enabling potential carcinogenic effects. However, typical local processing of this fish species markedly appeared to decrease these contaminant levels, thus making the fish product (called missoltino) a safer food. CONCLUSIONS: The results of this work highlighted the need of continuous biomonitoring of those contaminants considered a past issue along with the emergent ones.


Assuntos
DDT/análise , Peixes , Contaminação de Alimentos/análise , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Adulto , Animais , Monitoramento Ambiental , Humanos , Itália , Lagos , Medição de Risco , Alimentos Marinhos
17.
Sci Total Environ ; 538: 654-63, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26327633

RESUMO

Effect-based monitoring is a recommended approach suggested in European Guidelines to assess the response of ecosystem affected by a pollution source, considering the effects at community, population, individual but also at suborganism level. A combined chemical, ecological and genetic approach was applied in order to assess the impact of a fluoropolymer plant on the macrobenthic community of the Northern Italian river Bormida (Piedmont region). The macrobenthic community living downstream of the industrial discharge was chronically exposed to a mixture of perfluoroalkyl substances (PFAS), with perfluorooctanoic acid as the main compound, at concentrations up to several µgL(-1). Ecological assessment proved that the downstream community was not substantially different from that living upstream of the pollution source. The impact on community is not quantifiable with the traditional monitoring methods used for ecological classification under European regulation because macrobenthic communities showed only slight differences in their structure. In order to highlight effects on genetic variability of the native population, a subcellular analysis by using the AFLP (Amplified Fragment Length Polymorphism) genetic technique was applied to genotype of individuals of a selected species (Hydropsyche modesta, Trichoptera) collected in the two sampling sites. Percentage of variation between the two populations was 6.8%, a threshold compatible with a genetic drift induced in the downstream population. The genetic study carried out in field identified a significant divergence between exposed and non-exposed populations, but at present it is not possible to associate this divergence to a specific effect induced by PFAS.


Assuntos
Monitoramento Ambiental/métodos , Fluorocarbonos/análise , Invertebrados/crescimento & desenvolvimento , Polímeros/análise , Poluentes Químicos da Água/análise , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , Fluorocarbonos/toxicidade , Invertebrados/classificação , Invertebrados/genética , Polímeros/toxicidade , Rios/química , Poluentes Químicos da Água/toxicidade
18.
Bull Environ Contam Toxicol ; 94(1): 46-51, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25374368

RESUMO

Resurrecting legacy lineages of organisms from sediment cores of known geological age allows us to understand how environmental change can cause selection pressures that constrain the variation of populations over time. We quantified the lifetime tolerance and effects of Cu(II) exposure on Daphnia galeata in a polluted subalpine lake by comparing extant individuals with those resurrected from ephippia extracted from ca. 30-years-old sediments. Laboratory experiments were conducted using two Cu(II) concentrations, 40 and 10 µg L(-1), corresponding to the levels recorded in the lake, during chemical recovery, when Daphnia first re-appeared and succeeded. Contemporary Daphnia were unable to survive after the 10th day at either of the Cu(II) concentrations, and were unable to successfully reproduce. Daphnia cohorts from the past performed better in low Cu(II) concentrations than in copper-free, control conditions. The copper-adapted, tolerant Daphnia strains grew faster under non-toxic conditions, but were unable to survive new pollution events.


Assuntos
Cobre/toxicidade , Daphnia/efeitos dos fármacos , Animais , Daphnia/classificação , Exposição Ambiental , Lagos , Reprodução/efeitos dos fármacos
19.
Sci Total Environ ; 497-498: 499-507, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25151268

RESUMO

Due to its geographical peculiarities, the Republic of Maldives represents a case study of great interest for the investigation of persistent organic pollutants, from both a socio-economic and an ecological perspective. Thus, we conducted a first survey to assess the current status of polychlorinated dibenzo-p-dioxin (PCDD), polychlorinated dibenzofuran (PCDF) and dioxin-like polychlorinated biphenyl (DL-PCB) concentrations in Maldivian soils. The range for PCDD/F and DL-PCB soil concentrations was 0.01-49.3 pg WHO2005-TEQ g(-1) and 0.01-3.69 pg WHO2005-TEQ g(-1) dw respectively. PCDD/F concentrations exceeding several international soil guidelines were found in samples from locations in the proximity of local waste combustion sources. DL-PCB concentrations were lower than PCDD/Fs and comparable to those in previous reports from background areas and in areas with developing industrial and agricultural activities. PCDD/F and DL-PCB levels (expressed as WHO2005-TEQ) in soils were strongly correlated (r=0.89), which suggests that, in most of the sites, they are originated from the same emission sources. Results indicate that PCDD/F soil concentrations (expressed as WHO2005-TEQ) tend to decrease with the distance from the local pollution sources. Principal component analysis (PCA) showed that PCDD/Fs in the most polluted locations are mainly generated by waste combustion. These findings highlight the need for immediate changes in waste management policies in the Archipelago, in order to reduce the release of Persistent Organic Pollutants (POPs) in the fragile local environment.


Assuntos
Benzofuranos/análise , Monitoramento Ambiental , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análogos & derivados , Poluentes do Solo/análise , Poluição Ambiental/estatística & dados numéricos , Atividades Humanas , Humanos , Ilhas do Oceano Índico , Dibenzodioxinas Policloradas/análise , Gerenciamento de Resíduos
20.
Int J Mol Sci ; 15(6): 9497-518, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24879523

RESUMO

This study provides data to define an efficient biocide-free strategy based on zosteric acid to counteract biofilm formation on the membranes of submerged bioreactor system plants. 16S rRNA gene phylogenetic analysis showed that gammaproteobacteria was the prevalent taxa on fouled membranes of an Italian wastewater plant. Pseudomonas was the prevalent genus among the cultivable membrane-fouler bacteria and Pseudomonas putida was selected as the target microorganism to test the efficacy of the antifoulant. Zosteric acid was not a source of carbon and energy for P. putida cells and, at 200 mg/L, it caused a reduction of bacterial coverage by 80%. Biofilm experiments confirmed the compound caused a significant decrease in biomass (-97%) and thickness (-50%), and it induced a migration activity of the peritrichous flagellated P. putida over the polycarbonate surface not amenable to a biofilm phenotype. The low octanol-water partitioning coefficient and the high water solubility suggested a low bioaccumulation potential and the water compartment as its main environmental recipient and capacitor. Preliminary ecotoxicological tests did not highlight direct toxicity effects toward Daphnia magna. For green algae Pseudokirchneriella subcapitata an effect was observed at concentrations above 100 mg/L with a significant growth of protozoa that may be connected to a concurrent algal growth inhibition.


Assuntos
Biofilmes/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Cinamatos/metabolismo , Desinfetantes/metabolismo , Pseudomonas putida/fisiologia , Ésteres do Ácido Sulfúrico/metabolismo , Animais , Reatores Biológicos/microbiologia , Cinamatos/toxicidade , Daphnia/efeitos dos fármacos , Desinfetantes/toxicidade , Pseudomonas putida/genética , RNA Ribossômico 16S/genética , Ésteres do Ácido Sulfúrico/toxicidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...