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1.
Environ Sci Pollut Res Int ; 31(32): 45138-45161, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38961016

RESUMO

The extraction of phosphorite ore in Tunisia has resulted in the discharge of substantial amounts of phosphatic sludge into the region's water system. To mitigate this environmental issue and prevent heavy metal leaching, a geopolymerization process was employed using two types of Tunisian calcined phosphate sludges (Cal-PS1 and Cal-PS2) as substitutes for alkali-activated metakaolin. This study aimed to investigate and compare the physical and mechanical properties of the resulting geopolymers. The optimal substitution ratio of metakaolin with calcined phosphate sludge was determined to be 1.5, equivalent to 20 wt.% of calcined phosphate sludge. Compressive strength tests conducted after 28 days of curing revealed values of 37 MPa for Cal-PS1 specimens and 28 MPa for Cal-PS2 geopolymers while compressive strength of geopolymers soaked in water for 28 days showed a decrease with the addition of phosphate sludges. The specific surface areas of Cal-PS1 geopolymers ranged from 16.3 to 16.9 m2/g and from 17.62 to 18.73 m2/g for Cal-PS2 specimens exhibiting a mesoporous structure. The elasticity modulus of the geopolymers was found to increase with the increase of the apparent density of geopolymers and with the sludges content but it tended to be lower than the Portland cement elasticity modulus. Leaching test was conducted to evaluate the potential environmental applications of the geopolymers. This test demonstrated effective containment of heavy metals within the geopolymers' network, except for low levels of arsenic.


Assuntos
Fosfatos , Fosfatos/química , Esgotos/química , Caulim/química , Polímeros/química , Álcalis/química , Tunísia
2.
Environ Geochem Health ; 46(7): 226, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849664

RESUMO

The red deer is an ungulate and large game species. The contamination of the ecosystems by metal(loid)s may lead to the exposure of animals (as well as humans) through water and food resources. The direct contact of hunters and wild animal meat consumers with deer carcasses may be a potential contaminant source. This study aimed to determine the metal(loid)s' concentrations in the liver and kidney of red deer from two regions of Portugal (Idanha-a-Nova and Lousã), and to relate these with histopathologic lesions. Thirteen young male deer were submitted to metal(loid) determination (As, Cd, Co, Cr, Cu, Pb, and Zn) by inductively coupled plasma mass spectrophotometry (ICP-MS) and histopathology examination. Renal Cd (8.072 ± 5.766 mg/kg dw) and hepatic Pb (3.824 ± 6.098 mg/kg dw) mean values were high, considering the maximum values for consumption established by the European Commission. The hepatic mean value of Cu was significantly higher in Idanha-a-Nova (150.059 ± 33.321 mg/kg dw), and it is at the Cu toxicity limit considered for ruminants (150 mg/kg). The pollution induced by Panasqueira mines (Castelo Branco) may be a possible explanation for some of the findings, especially the higher values of hepatic Cu and Pb found in Idanha-a-Nova deer. These results have high importance under a One Health perspective, since they have implications in public health, and pose at risk the imbalance of animal populations and ecosystems.


Assuntos
Cervos , Rim , Fígado , Metais Pesados , Animais , Metais Pesados/análise , Masculino , Fígado/metabolismo , Humanos , Portugal , Rim/efeitos dos fármacos , Metaloides/análise , Metaloides/toxicidade , Monitoramento Ambiental , Poluentes Ambientais , Exposição Ambiental
3.
Environ Sci Pollut Res Int ; 31(8): 11983-11994, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38225500

RESUMO

The western-European hedgehog (Erinaceus europaeus) is an insectivore with a wide distribution in Portugal and a potential tool for biomonitoring relevant One Health hazards, including heavy metal(loid)s' pollution. The aim of this study was to positively contribute to the current knowledge about the metal(loid) pollution in Portugal. Forty-six hedgehogs (from rescue centres; with known provenance) were necropsied. Sex, age category and weight were determined. Spines, liver and kidney were collected, and metalloid concentrations were determined by inductively coupled plasma mass spectrophotometry (ICP-MS). In general, results did not present alarming metal(loid) concentrations, with the exception of cadmium (Cd) (in the kidneys) and copper (Cu). Hedgehogs from Viana do Castelo and Viseu showed elevated concentrations of arsenic (As) and Castelo Branco presented concerning values of cadmium (Cd). Adult and heavier hedgehogs tended to present higher levels of metal(loid)s. Sex does not seem to significantly affect the metal(loid)s' concentrations. Further analysis would be needed to prioritize areas with detail and allow the application of the necessary mitigation strategies.


Assuntos
Metaloides , Metais Pesados , Animais , Cádmio/análise , Portugal , Ouriços , Monitoramento Ambiental/métodos , Metais Pesados/análise , Metaloides/análise , China , Medição de Risco
4.
Vet Res Commun ; 48(2): 1015-1023, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38052737

RESUMO

Wild boars (Sus scrofa) are part of the hunting economy and are highly consumed in the Iberian Peninsula, including in the Castile and Leon regions. As zoonotic diseases, chemical pollutants in wild boars' internal tissues should be interpreted as evidence of environmental contamination and a matter of concern for animal, human and ecosystem health; in other words, a One Health concern. Twenty-eight wild boars' livers and kidneys (n = 28) from Castile and Leon were submitted to metal(loid) determination (As, Cd, Co, Cr, Cu, Ni, Pb, and Zn) with inductively coupled plasma mass spectrophotometry (ICP-MS) and histopathological exam. Cd levels, especially in the kidneys (7.063 ± 7.271 mg/kg dw), were the most concerning results, considering the calculated maximum values for consumption (EC No. 915/2023) (2.491 mg/kg dw or 1.0 mg/kg ww). Wild boars with hydropic changes in the liver presented higher concentrations of Ni. Thus, the metal(loid) contamination of wild boar carcasses seems to be a "no trace" but very relevant problem that should raise awareness of a more accurate monitoring program and other strategies to avoid public health consequences.


Assuntos
Metaloides , Metais Pesados , Humanos , Animais , Suínos , Cádmio/análise , Metaloides/análise , Saúde Pública , Ecossistema , Monitoramento Ambiental/métodos , Metais Pesados/análise , Sus scrofa
5.
Animals (Basel) ; 13(8)2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37106922

RESUMO

Heavy metal(loid) pollution of ecosystems is a current One Health problem. The liver is one of the most affected organs in cases of acute or chronic exposure to abnormal amounts of these substances, inducing histopathologic lesions. In order to assess the influence of heavy metal(loids), forty-five European hedgehogs (Erinaceus europaeus) were submitted to necropsy, and liver samples were collected for a routine histopathology exam and metal(loid)s determination (As, Cd, Co, Cr, Cu and Pb) by ICP-MS. Age was estimated during the necropsy exam. Biliary hyperplasia was the most frequent lesion observed (16/45; 35.56%). No statistically significant associations were found between biliary hyperplasia and age or sex. Metal(loid)s' concentrations were higher in animals with biliary hyperplasia (except for As). There was a statistically significant difference for both Cd and Co. For As, Cd and Co, cubs and juveniles animals showed significantly lower concentrations than elder individuals. Only for Pb were significant differences found between females and males. As described in the literature, exposure to metal(loid)s may be a cause of biliary hyperplasia, although further research (including the use of biochemical methods) is needed to support these results. To the authors' knowledge, this is the first report of this association in hedgehogs.

6.
Data Brief ; 25: 104285, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31463345

RESUMO

This paper presents baseline data of sediments characterization from Ria de Aveiro lagoon (Portugal). Twenty-two intertidal surface sediments were collected and analysed for their pseudo-total content of 25 major and trace elements and for their total content of PAHs (Sum16) and PCBs (Sum13). The fine fraction percentage and total organic carbon content were also determined. Ria de Aveiro Lagoon has been the target of several studies during the last decades, and it has been pointed out as a hot spot in terms of contamination García-Seoane et al., 2016. Nevertheless, data about sediments contamination is mostly focused on Hg Lillebø et al.,2011, and in a specific area of the lagoon Grilo et al., 2013, and there is not a clear and global picture about the spatial distribution of other elements, and especially of organic contaminants. Thus, this baseline dataset is of utmost importance for researchers and planners and it can be used to monitor the effect of disturbances, such as: dredging activities; hydrodynamic changes (either due to human activities or extreme events); external inputs (new discharges from industries and wastewater plants, etc).

7.
Mar Pollut Bull ; 103(1-2): 319-324, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26778497

RESUMO

Fecal sterols in sediments were used to assess the degree of sewage contamination in Ria de Aveiro lagoon and Mondego River estuary for the first time. Coprostanol, the major fecal sterol, averaged 1.82 ± 4.12 µg g(-1), with maxima of 16.6 µg g(-1). The northwestern sector of the Ria and a marina at Mondego estuary showed the highest level of sewage contamination. This scenario was confirmed by several diagnostic ratios based on fecal sterols and other phytosterols. Our data revealed that in spite of the improvements achieved in the last decades, there is still a need for control the organic inputs into the aquatic environment in the studied regions.


Assuntos
Monitoramento Ambiental/métodos , Fezes/química , Sedimentos Geológicos/química , Rios/química , Esgotos/análise , Esteróis/análise , Oceano Atlântico , Colestanol/análise , Estuários , Portugal
8.
Chemosphere ; 93(8): 1632-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24021414

RESUMO

Polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB) are organic contaminants that tend to accumulate in fish. Estuaries are exposed to high anthropogenic activities, therefore tending to accumulate more contaminants than the adjacent coastal waters. Platichthys flesus, a fish with high economic value, was analysed for PCBs and HCB along its different age groups, in liver, gills, gonads and muscle. Younger fishes were caught in the estuary, whereas older fishes were caught in the adjacent coastal waters and acquired at Figueira da Foz Regional Office of Docapesca-Portos e Lotas, SA. Both contaminants concentrations follow the pattern: liver>gills>muscle. Hepatosomatic index had the lowest values in younger fishes and the highest values in older fishes. Condition factor values remain stable with age. Younger fishes had higher PCBs concentrations than the older fishes. In opposition HCB was only detected in fish from 3+ to 5+ and its concentration tended to increase with age. Overall P. flesus is considered safe for human intake.


Assuntos
Monitoramento Ambiental , Linguado/metabolismo , Hexaclorobenzeno/metabolismo , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Brânquias/metabolismo , Gônadas/metabolismo , Fígado/metabolismo , Músculos/metabolismo
9.
Ecotoxicol Environ Saf ; 94: 147-52, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23735896

RESUMO

Polychlorinated biphenyls (PCBs) are lipophilic contaminants that tend to accumulate in organisms. PCBs were detected in Chelon labrosus, Liza aurata and Liza ramada, along different age groups. L. ramada presented the highest concentration, and it increased with age, whereas C. labrosus and L. aurata concentration remained constant. L. ramada high concentration can be attributed to its ecological niche, since this species is able to accumulate PCBs along its different age groups even in low environmental contamination conditions. PCBs 101, 118, 138, 149, 153, 170 and 180 were the congeners that more contributed to these species contamination, being PCB 138 and 153 the congeners with higher concentration. Mullets are edible in many countries, being important in fisheries and aquaculture. L. ramada is the most common mullet for capture and human consumption. All species presented concentrations below the regulation limit establish by the European Union, and therefore safe for human consumption.


Assuntos
Bifenilos Policlorados/metabolismo , Alimentos Marinhos/estatística & dados numéricos , Smegmamorpha/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Aquicultura/estatística & dados numéricos , União Europeia , Pesqueiros/estatística & dados numéricos , Poluição Química da Água/estatística & dados numéricos
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