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1.
J Environ Biol ; 2020 Jul; 41(4): 761-769
Article | IMSEAR | ID: sea-214540

Résumé

Aim: The present study aimed to assess the phytoextraction potential of plant geranium (CIM BIO-171) to remove metals from sewage sludge and to investigate the growth, yield and quality of essential oil of this aromatic plant grown in contaminated sludge.Methodology: The experiment was conducted at research farm of CSIR-CIMAP, Lucknow during 2017-18 in vertical cemented column pots dug into soil. Six treatment groups of sewage sludge and soil were taken with four replication, i.e., T1-100% sewage sludge, T2-80% sewage sludge + 20% soil, T3-60% sewage sludge + 40% soil, T4-40% sewage sludge + 60% soil, T5-20% sewage sludge + 80% soil and T6-soil (only soil). Experimental soil was analysed at pre-harvest and post-harvest stage for soil characters. All plant attributes were recorded at the time of harvesting. Results: Result of the present study showed reduction in the heavy metals in the soil at harvest in comparison to the contents observed in soil at initial stage. All the parameters of growth, yield, biomass and essential oil were found to increase with the application rate of sewage sludge in geranium (CIM BIO-171). Interpretation: The results of the present study clearly indicate the phytoextraction capability of geranium plant (CIM BIO-171). Furthermore, the plants grown in contaminated sludge has all the beneficial impact on growth, yield and quality of essential oil.

2.
Article | IMSEAR | ID: sea-189640

Résumé

Potentially toxic metals (PTM), along with PTM-resistant bacteria and PTM-resistance genes may be introduced to soil and water through sewage systems, direct excretion, land application of biosolids (organic matter recycled from sewage, especially for use in agriculture) or animal manures as fertilisers, and irrigation with wastewater or treated effluents. The Norwegian Food Safety Authority (NFSA) asked the Norwegian Scientific Committee for Food Safety (Vitenskapskomiteen for mattrygghet, VKM) for an assessment of the link between antimicrobial resistance (AMR) and potentially toxic metals (PTM) in soil and fertilising products. The NFSA would like VKM to give an opinion on the following question related to the influence of potentially toxic metals on antimicrobial resistance: Can the content of arsenic (As), cadmium (Cd), chromium (CrIII + CrVI), copper (Cu), lead (Pb), mercury (Hg), nickel (Ni), and zinc (Zn) in soil and fertilising products that are relevant for Norway play a role in the development, spreading, and persistence of bacterial resistance to these elements, as well as cross or co-resistance to antimicrobial agents? VKM appointed a working group, consisting of two members of the Panel on Biological Hazards, to prepare a draft Opinion document and answer the questions. The Panel on Biological Hazards has reviewed and revised the draft prepared by the working group and approved the Opinion document “The link between antimicrobial resistance and the content of potentially toxic metals in soil and fertilising products”. In this report we assess the following PTM: arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), mercury (Hg), lead (Pb), and zinc (Zn), because of their possible presence in fertilisers and their potential to induce AMR in bacteria. This assessment is based on internationally published data. There is no systematic monitoring for toxic metals in soils in Norway, and the levels are expected to be highly variable depending on the input sources, previous and current agricultural practices, and the characteristics of the soil. Data on PTM in fertilising products added to soil are also fragmented and limited. Fertilising materials, in the form of sewage sludge or livestock manure, will add toxic metals to the existing levels in soil, and in areas of intensive agriculture, the levels will be expected to be highest. The additive effect of toxic metals in fertilising materials must be assessed from a long-term perspective, as these metals accumulate in the environment. Development of AMR can be partly regarded as a dose- and time-dependant response to exposure to different drivers for resistance. There is an indication that the presence of potentially toxic metals is a driver for development of AMR in exposed bacteria, but the dose and time exposure most likely to cause this effect is not known. Investigation of PTM-driven co-selection of AMR in environments impacted by agriculture and aquaculture should focus especially on Cu and Zn, which are added to animal feed, and on Cd because of its high concentration, in comparison with other PTM, in inorganic fertilising products. The naturally occurring background resistance in environmental bacteria complicates the estimation of the effect of PTM exposure on development of resistance. In addition, it is difficult to distinguish between the natural resistome and an elevated abundance of AMR in environmental samples. Spreading of resistance towards the PTM evaluated in this assessment involves cross- and co-resistance to antimicrobial agents used in prophylaxis and therapy in animals and people. Most important are those cases where toxic metal resistance is coupled to resistance towards highly important and critically important antibiotics. This has been described in some of the published articles included in this assessment. We do not fully understand the mechanisms behind persistence of AMR, and removing drivers for development and spread of resistance may result in a decrease in the levels of resistance, but not necessarily full disappearance. There is lack of knowledge regarding links between the level and concentration of PTM in fertilising products and soil and development of resistance in bacteria. Data regarding the routes and frequencies of transmission of AMR from bacteria of environmental origin to bacteria of animal and human origin were lacking in the published articles reviewed here. Due to the lack of such data, it is difficult to estimate the probability of development, transmission, and persistence of PTM resistance in the Norwegian environment. More research is needed to explain the relationship between development of resistance against potential toxic metals and resistance toward antimicrobial agents in bacteria.

3.
Article | IMSEAR | ID: sea-188037

Résumé

Correlational study and evaluation of pollution indices of toxic metals distribution in soil and crops of a population are imperative for assessing the risk of chronic diseases associated with these metals. Correlational analysis for the distribution of; lead (Pb), cadmium (Cd), chromium (Cr) and mercury (Hg) in soil (S), bean (B) and maize (M) was conducted around Bunkure (BKR), Danbatta (DBT), Gwarzo (GRZ), Ungogo (UGG) and Wudil (WDL) as sampling zones around Kano State, Nigeria. The samples were collected from farm harvests in each of the sampling zones. The metal concentration was determined using atomic absorption spectrometry (AAS). Results in mg/kg across the local governments indicate respective ranges for Hg, Pb, Cd, and Cr of; 0.33 - 3.13, 0.14 - 0.84, 0.02 - 0.05 and 0.01- 0.49 in soil, 0.04-4.23, 0.06-0.23, 0.02-0.04 and 0.00-0.10 in maize and 0.20-4.23, 0.16-0.19, 0.03-0.04 and 0.00-0.03 in beans. Although with the exception of mercury, the ranges of the toxic metals are within the tolerable range set by International Standard Tolerable Limits and European Regulatory Standard. Potential hazard may be speculated because the detected levels are on higher tolerable ranges. A higher level of mercury in almost all the samples indicates potential hazards associated with human activities in those areas. A strong positive correlation between soils samples in respect to the level of some of the toxic metal may suggest a common nature of the soil, while the negative correlation may be due to variation in agrochemicals in-use. For the pollution load index, Wudil had the highest soil pollution load index for Hg (3.13 ± 0.16), Cd (1.6×10-2 ± 0.01) and Cr (4.9×10-3 ± 0.01), while Ungogo had the highest pollution load for Pb. Also, all grains within the study zones exhibited a positive transfer factor, except Cr in Bunkure, Danbatta and Gwarzo. It may be concluded that crops grown in those areas may bioaccumulate some of these toxic metals, thereby incorporating them into the food chain, hence potential health risk.

4.
Eng. sanit. ambient ; 24(2): 335-346, mar.-abr. 2019. tab, graf
Article Dans Portugais | LILACS-Express | LILACS | ID: biblio-1012038

Résumé

RESUMO O cromo é um metal tóxico amplamente utilizado em processos industriais, por isso a constante preocupação com os efluentes líquidos gerados. Uma vez lançados sem o devido tratamento podem comprometer a qualidade do corpo receptor. Este trabalho teve por objetivo analisar o processo de biossorção na remoção de íons Cr(III) de soluções aquosas sintéticas e efluente de curtume utilizando como biossorvente a macrófita aquática Pistia stratiotes in natura (PN) e quimicamente modificada (PM) com hidróxido de sódio e ácido cítrico. Realizou-se o preparo, a caracterização dos biossorventes e os experimentos de biossorção. Os estudos de equilíbrio indicaram que a capacidade máxima de biossorção foi de 58,16 e 19,80 mg g-1 para PM e PN, respectivamente. Nos testes utilizando efluente bruto de curtume, a remoção de cromo foi de 28,26% para ambos os biossorventes, e no efluente da lagoa de tratamento biológico, a maior taxa de remoção do metal foi obtida pelo biossorvente PM, com 65,44%. Os resultados demonstraram que a utilização de P. stratiotes como biossorvente apresenta-se como uma alternativa eficaz e de baixo custo, porém estudos complementares são necessários a fim de avaliar sua aplicação em escala real.


ABSTRACT Chromium is a toxic metal widely used in industrial processes, so the concern with the liquid effluents generated is constant, that once released without proper treatment can compromise the quality of the receiver body. The study aimed at analyzing the process of biosorption in removing Cr(III) ions of synthetic aqueous solutions and tannery effluent using as biosorbent the Pistia stratiotes macrophyte in natura (PN) and chemically modified (PM) with sodium hydroxide and citric acid. The preparation, characterization of the biosorbents and the experiments of biosorption were performed. Equilibrium studies indicated that the maximum biosorption capacity for PM was 58.16 mg g-1 and 19.80 mg g-1 for PN. In the tests using raw effluent from tannery, chromium removal was 28.26% for both biosorbents, and in the effluent from biological treatment lagoon, the higher rate of metal removal was obtained by biosorbent PM with 65.44%. The results showed that the use of P. stratiotes as biosorbent may be an effective and low-cost alternative and that additional studies are needed to assess its full-scale application.

5.
Ciênc. rural (Online) ; 49(11): e20190279, 2019. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1045261

Résumé

ABSTRACT: Toxic metals contamination of soil has become a serious problem in recent years. In this study, Chinese cabbage (a relatively high-accumulator of cadmium (Cd)) and cabbage (a relatively low-accumulator of Cd) were cultured in monoculture and in intercropping in the Cd-contaminated soil, to evaluate the effect of intercropping on the alteration of Cd extraction. Both the pot experiments and field experiments indicated that intercropping increased the Cd extraction by Chinese cabbage and decreased the Cd extraction by cabbage. Thus, Cd extraction was advanced while safe production was obtained. Further pot experiment was conducted to investigate the alterations of soil Cd fractions, soil pH, and soil enzyme activities to reveal their possible relationship with Cd extraction between different planting patterns. Results revealed that three individual Chinese cabbages in one intercropping pot played the same effect on alteration of these factors as six individual Chinese cabbages in one monoculture pot. The intercropping increased Cd extraction by Chinese cabbage and decreased Cd extraction by cabbage, probably by influencing mechanisms such as soil enzyme activities (especially the urease activity) in the cultivation system. Effect of intercropping on Cd accumulation is an important issue in cultivation of vegetables in potentially contaminated land.


RESUMO: A contaminação do solo por metais tóxicos tornou-se um problema grave nos últimos anos. Neste estudo, dois tipos de repolhos, o repolho chinês (maior acumulador de cádmio (Cd)) e o repolho comum (menor acumulador de Cd) foram cultivados em monocultivo e em consórcio, em solo contaminado com esse metal, para avaliar o efeito do consórcio na extração de Cd do solo. Os experimentos em vasos de campo indicaram que o consórcio aumentou a extração desse metal pelo repolho chinês e diminuiu a extração pelo repolho comum. Assim, aumentou a extração de Cd do solo, proporcionando segurança alimentar. Outro experimento em vaso foi conduzido para investigar as alterações das frações de Cd do solo, o pH do solo e atividades enzimáticas do solo, para revelar possíveis efeitos na extração desse metal entre os sistemas de plantio. Os resultados do experimento em vaso revelaram que três repolhos da china, em cultivo consorciado, proporcionaram o mesmo efeito nessas variáveis, que os observados com seis plantas desse tipo de repolho, em monocultura. O consórcio influenciou as frações de Cd do solo devido a maior influência das hortaliças no pH do solo e nas atividades enzimáticas (especialmente a urease), resultando maior extração de Cd pelo repolho chinês e menor pelo repolho comum.

6.
Malaysian Journal of Microbiology ; : 108-112, 2018.
Article Dans Anglais | WPRIM | ID: wpr-732358

Résumé

@#Aims: To study the performance of SMFC in the terms of power generation and toxic metals removal. This study was also focused on the characterization of SMFC electro-microbiology. Methodology and results: A SMFC was designed and loaded with sediment and overlying water. This SMFC was synchronized with wireless data logger acquisition system. The toxic metals removal capacity was measured by atomic absorption spectroscopy. The characterization of SMFC bacteria was done by 16S rRNA.In this study the experiments were carried out in a dual-chamber SMFC with external resistances 30 kΩ-50 Ω. The SMFC was produced power about 630 mV with maximum power density 40 mW/m2and current density 250 mA/m2. After 120 days of operation, SMFC removed cadmium and copper about 22.6 and 150 mg/kg, respectively. The SMFC also showed high cadmium (86%) and copper (90%) removal at pH 7.0 and temperature 40 °C. The most dominant bacterial community at anode and cathode was identified as Pseudomonas spp. which could be function as exoelectrogen. Conclusion, significance and impact of the study: The results indicated that the SMFC system could be applied as a long term and effective tool for the removal of cadmium and copper contaminated sediments and supply power for commercial devices. The Pseudomonas spp. may be used as a genetic donor for the other non-exoelectrogens strains.

7.
Acta amaz ; 46(2): 195-208, abr.-jun. 2016. ilus, tab
Article Dans Portugais | LILACS, VETINDEX | ID: biblio-1455294

Résumé

Piper arboreum Aubl. var. arboreum and P. tuberculatum Jacq. (Piperaceae), both known as "pimenta-longa", are frequently misidentified. Despite the fact that both species are sold as traditional phytotherapeutic products, there are no reports on their quality control. The aim of this study was to prepare and characterize leaf and stem herbal drugs of both species using standard methods aiming to establish parameters for botanical authentication and purity degree for their quality control. Size, shape, color, taste, texture, fracture surface and transection characteristics, and leaf venation patterns are macroscopic diagnostic characters useful to distinguish the herbal drugs when they are not powdered. The following characters are useful for diagnostic purposes of the powdered herbal drugs: cuticular and epicuticular wax patterns, types of trichomes, and wall thickening of the tracheary elements, and shape of the hilum of the starch grains. Emergences are key morphological markers for P. tuberculatum herbal drugs. Physicochemical parameter values were similar in herbal drugs of both species, except acid-insoluble ash value which was higher in the P. arboreum var. arboreum stem herbal drugs. Piper arboreum var. arboreum herbal drugs had the highest metal concentrations. Al, Cu, Mn and V concentrations were the highest, whereas Cd, Co and Hg concentrations were the lowest in the herbal drugs of both species. The results obtained can be used as quality control parameters for the herbal drugs of both species.


Piper arboreum Aubl. var. arboreum e P. tuberculatum Jacq. (Piperaceae), conhecidas como pimenta-longa, são comercializadas como produtos tradicionais fitoterápicos e, frequentemente, identificadas erroneamente, não havendo relatos sobre controle de qualidade dessas espécies. O objetivo do trabalho foi preparar e caracterizar drogas vegetais foliares e caulinares dessas espécies para estabelecer-lhes parâmetros de autenticidade botânica e grau de pureza para o controle de qualidade. Foram utilizados métodos padrões para o preparo e análises estrutural e físico-química das drogas vegetais. São caracteres diagnósticos macroscópicos para distinguir as drogas vegetais íntegras: tamanho, forma, cor, sabor, textura, características da superfície de fratura e da secção transversal e os padrões de venação foliar. São caracteres diagnósticos para distinguir as drogas vegetais pulverizadas: padrões de cutícula e cera epicuticular, tipos de tricoma e espessamento parietal dos elementos traqueais e a forma do hilo dos grãos de amido. Emergências são marcadores morfológicos chave para as drogas vegetais de P. tuberculatum. Os valores dos parâmetros físico-químicos foram similares nas drogas vegetais das espécies, exceto o de cinzas ácido-insolúveis que foi maior nas drogas vegetais caulinares de P. arboreum var. arboreum. As maiores concentrações de metais ocorreram nas drogas vegetais de P. arboreum var. arboreum. As concentrações mais elevadas foram de Al, Cu, Mn e V e as mais baixas de Cd, Co e Hg. Os resultados obtidos poderão ser utilizados como parâmetros de controle de qualidade para as drogas vegetais de ambas as espécies.


Sujets)
Capsicum/composition chimique , Médicaments Phytothérapeutiques , Métaux/toxicité , Piper/composition chimique , Phénomènes chimiques
8.
Biomedical and Environmental Sciences ; (12): 187-196, 2016.
Article Dans Anglais | WPRIM | ID: wpr-258835

Résumé

<p><b>OBJECTIVE</b>Assessment of the bacterium L. sphaericus as a dual-action candidate for biological control of mosquito-borne diseases and bioremediation of toxic metals.</p><p><b>METHODS</b>Larvae of the mosquito, C. quinquefasciatus, were first evaluated for metal tolerance and then exposed to 5 ppm cadmium, chromium, arsenic, and lead in assays together with seven strains of L. sphaericus. A probit regression analysis was used to estimate the LC(50) of Cd, Cr, As, and Pb to C. quinquefasciatus. An analysis of covariance and multifactorial ANOVA examined the metal biosorption and larvicidal properties of the seven strains of L. sphaericus.</p><p><b>RESULTS</b>We found that L. sphaericus adsorbed the toxic metal ions and was toxic against mosquito larvae. The L. sphaericus strain III(3)7 resulted in a larvae mortality of over 80% for all the tested metals. This strain also exhibited the capacity to adsorb 76% of arsenic, 32% of lead, 25% of chromium, and 7% of cadmium.</p><p><b>CONCLUSION</b>This study found combined metal adsorption and larval toxicity associated with three strains of L. sphaericus [III(3)7, OT4b.31, and CBAM5]. This suggests that a combination of these strains shows strong dual potential for biological control of mosquitos in heavy metal-contaminated areas and remediate the heavy metal contamination as well.</p>


Sujets)
Animaux , Bacillaceae , Physiologie , Culicidae , Microbiologie , Interactions hôte-pathogène , Vecteurs insectes , Larve , Microbiologie , Métaux lourds , Métabolisme , Toxicité , Polluants chimiques de l'eau , Métabolisme , Toxicité
9.
Ciênc. rural ; 45(3): 560-566, 03/2015. tab, graf
Article Dans Portugais | LILACS | ID: lil-741400

Résumé

Este estudo teve como objetivo avaliar a composição mineral de diferentes tipos de cascas de ovo, bem como a segurança microbiológica de amostras submetidas a diferentes métodos de higienização. Para a obtenção do pó de casca de ovo, as cascas foram lavadas, higienizadas, secas em estufa e trituradas em moinho. Cascas de ovo de granja (criação confinada), de coloração branca e vermelha, e cascas de ovo coloniais (caipira), provenientes da região central do Rio Grande do Sul, foram comparadas quanto a sua composição mineral. O Ca, mineral predominante na casca de ovo, se manteve em concentrações semelhantes nas diferentes amostras (cerca de 365mg g-1). As cascas de ovo de granja apresentaram maior concentração de Mg e menor concentração de Sr que as cascas de ovo coloniais. Não foram encontradas quantidades significativas de Fe, Cr, Mn, Mo, Ni, Se, Al, Cd e Pb nas amostras analisadas. Adicionalmente, tanto amostras higienizadas com imersão em hipoclorito e posterior fervura em água, quanto amostras nas quais a imersão em hipoclorito foi suprimida, não apresentaram contaminação por coliformes, estafilococos ou salmonela. Os resultados indicam que a casca de ovo pode ser utilizada na nutrição humana, já que é rica em Ca, não apresenta contaminação por metais tóxicos e, se processada de forma adequada, apresenta boa qualidade higiênico-sanitária.


This study aimed to evaluate the mineral composition of different kinds of eggshell, as well as the microbiological safety of samples submitted to different sanitization procedures. To obtain the eggshell powder, the shells were washed, sanitized, oven dried and grinded in a mill. White- and brown-colored eggshells from confined laying hens and eggshells from free-ranged laying hens from the central region of Rio Grande do Sul were compared for their mineral composition. Ca, the predominant mineral in eggshells, remained at similar concentrations in the different samples (approximately 365mg g-1). Eggshells from confined laying hens had higher Mg concentration and lower Sr concentration than the shells from free-ranged laying hens. No significant amounts of Fe, Cr, Mn, Mo, Ni, Se, Al, Cd or Pb were found in the samples. Additionally, both samples that were sanitized by immersion in hypochlorite and subsequently boiled in water as well as samples in which hypochlorite immersion was suppressed did not show coliform, staphylococcus or salmonella contamination. The results indicate that eggshell can be used in human nutrition since it is rich Ca source, shows no contamination by toxic metals and has good sanitary quality when properly processed.

10.
Article Dans Anglais | IMSEAR | ID: sea-157864

Résumé

A series of transition elements complexes with [2,6-diacetimino-pheylenediamine – [2,2,diyl] pyridine] of the general formula [MLCl]Clx, (where M= Cr(III), Pb(II), Zn(II) and Cd(II), x= 2 for Cr(III)) respectively have been synthesized and fully characterized on the bases of C.H.N.M, elemental analysis, 13C NMR, UV- Visible and FTIR spectra , in addition the structure of complexes was characterized by magnetic moments and molar conductance in DMF solution ,and molar ratio of complexes were also determined. On the basis ofelectronic spectral studies .All complexes have an octahedral geometry around the metal center in (1:1) (L:M). A theoretical treatment of the formation of complexes in the gas phase was studied, this was done using the HYPERCHEM-6 program for the Molecular mechanics and Semiempirical calculations. The batch adsorption method has applied on N5 polydentate ligand to remove the selected toxic metal ions from waste water after immobilization the newly n5-ligand on silica gel by physic-chemical method.

11.
Article Dans Anglais | IMSEAR | ID: sea-162575

Résumé

In this study, inhalable particulate matter was sampled using the TEOM series 1400a, the elemental composition of the particulate matter was determined using Scanning Electron Microscopy coupled with Energy Dispersive Spectrometer (SEM/EDS) and the concentration of particulate nitrates and sulphates was analyzed using Ion Chromatography (IC). These parameters were evaluated to obtain an estimate of the composition of inhalable particulate matter (PM10) in Rustenburg, South Africa. The toxicity was also determined in terms of ratios of toxic metals to PM10, as well as to elemental carbon, nitrates and sulphates. The components of PM10 were obtained as follows: organic, halides, sulphates, crustal metals, toxic metals, nitrates, and carbon. The main toxic metals were obtained in order of decreasing abundance as Cr>Pb>Ni>V. Seasonal variations showed high levels of PM10 and sulphates in spring and high nitrate levels in summer. The SEM/EDS showed the presence of atmospheric particles of complex composition including S, Si, Al, Mg, Ca, Pb, Fe, Cr, Ni, V, and Pb.

12.
Ciênc. rural ; 39(5): 1591-1594, ago. 2009. tab
Article Dans Portugais | LILACS | ID: lil-521186

Résumé

Tendo em vista que o Brasil é um grande produtor e consumidor de café, fica evidente a importância de sua caracterização em diferentes locais de cultivo. O objetivo do presente estudo foi quantificar os teores de metais pesados em amostras de grãos de café, provenientes de lavouras implantadas em solos oriundos do basalto e do arenito Caiuá do Estado do Paraná. Foram examinadas 30 amostras de grãos de café, sendo 15 cultivados em solos predominantemente arenosos e 15 em solos argilosos. A determinação de Cromo (Cr), Cobalto (Co), Níquel (Ni), Chumbo (Pb), Cádmio (Cd), Cobre (Cu), Zinco (Zn) e Manganês (Mn) foi feita por espectrometria de emissão atômica com fonte de plasma induzido com Thermo Jarrel-ash ICAP 612 E (ICP-EAS). Os níveis foram variáveis entre as amostras.


Considering that Brazil is a big producer and coffee consumer its evident the importance of its characterization in the different places of cultivation. The purpose of the present study was quantify the levels of high metals in coffee grains samples 'IAPAR 59' derived from farming introduced in basalt and Caiuá sandstone soils in Paraná, Brazil . Thirty ground samples were examined, being 15 of predominantly arenaceous ground and 15 of argillaceous ground. The determination of Chrome (Cr), Cobalt (Co), Nickel (Ni), Lead (Pb), Cadmium (Cd), Copper (Cu), Zinc (Zn) and Manganese (Mn), was made through atomic emission spectrometry with induced plasma source with Thermo 612 Jarrel-ash ICAP E (ICP-EAS). The levels changed among the samples.

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