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1.
Braz. j. biol ; 83: e247562, 2023. tab, graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1339410

ABSTRACT

Abstract To investigate the role of cow dung in soil reclamation and bio assimilation along with bio accumulation of heavy metals in earthworm (P. posthuma) (N=900) earthworms were used and treatment groups of CD-soil mixture of different proportion of cow dung were designed. Nonlethal doses of lead acetate and cadmium chloride were added in treatment groups. Mature P. posthuma were released in each experimental pot maintaining the favorable conditions. The pH, carbon, nitrogen, phosphorus, exchangeable cations, and heavy metal level of each mixture was evaluated. The results indicated that bio-assimilation of Pb and Cd by P. posthuma were significantly (P ˂ 0.01) higher in different soil-CD treatments compared to control. Highest bio-assimilation of both metals was observed in T1 of both groups (Pb = 563.8 mg/kg and Cd = 42.95 mg/kg). The contents of both metals were significantly (P ˂ 0.05) lowered in casting. The nutrient concentration in the final castings of all soil-CD treatments were also equally transformed from less or insoluble to more soluble and available for plants, except for carbon level which increased with CD proportion. It is concluded that cow dung as organic matter has a positive effect on soil reclamation and bio-assimilation of metals by P. posthuma.


RESUMO Para investigar o papel do esterco de vaca na recuperação do solo e bioassimilação, juntamente com a bioacumulação de metais pesados ​​em minhocas (P. posthuma) (N = 900), minhocas foram usadas e grupos de tratamento de mistura CD-solo de diferentes proporções de esterco de vaca foram projetados. Doses não letais de acetato de chumbo e cloreto de cádmio foram adicionadas aos grupos de tratamento. P. posthuma maduros foram liberados em cada vaso experimental, mantendo as condições favoráveis. Foram avaliados o pH, carbono, nitrogênio, fósforo, cátions trocáveis ​​e nível de metais pesados ​​de cada mistura. Os resultados indicaram que a bioassimilação de Pb e Cd por P. posthuma foi significativamente (P ˂ 0,01) maior em diferentes tratamentos de solo-CD em relação ao controle. A maior bioassimilação de ambos os metais foi observada em T1 de ambos os grupos (Pb = 563,8 mg / kg e Cd = 42,95 mg / kg). O conteúdo de ambos os metais foi significativamente (P ˂ 0,05) reduzido na fundição. A concentração de nutrientes nas fundições finais de todos os tratamentos de solo-CD também foi igualmente transformada de menos ou insolúvel para mais solúvel e disponível para as plantas, exceto o nível de carbono que aumenta com a proporção de CD. Conclui-se que o esterco de vaca como matéria orgânica tem um efeito positivo na recuperação do solo e na bioassimilação de metais por P. posthuma.


Subject(s)
Animals , Female , Oligochaeta , Soil Pollutants , Metals, Heavy/analysis , Soil , Cadmium , Cattle , Bioaccumulation
2.
Braz. j. biol ; 82: e243633, 2022. tab, graf
Article in English | LILACS | ID: biblio-1249273

ABSTRACT

Abstract Snow trout (Schizothorax plagiostomus) is an economically important freshwater fish, mostly found in northern areas of water reservoirs of Pakistan. The current study was conducted in River Swat to analyze the bioaccumulation of heavy metals (Pb, Cr, Ni, and Zn) in tissues of Schizothorax plagiostomus. Tissues were extracted and dissolved in perchloric acid (HClO4) and nitric acid (HNO3) along with hotplate. The heavy metals, zinc (Zn), lead (Pb), chromium (Cr), and Nickel (Ni) were determined using Perkin Elmer 2380 atomic absorption spectrophotometer. Results shows great variation in the content of the metal related to tissue type and sampling sites. A high concentration of bioaccumulation was reported at Charbagh, whereas lowest at Odigram: Charbagh>Landakai>Odigram. In the same way, Cr was the most accumulated heavy metal followed by lead, nickel, and Zinc:


Resumo A truta das neves (Schizothorax plagiostomus) é um peixe de água doce economicamente importante, encontrado principalmente nas áreas ao norte de reservatórios de água do Paquistão. O presente estudo foi realizado em River Swat para analisar a bioacumulação de metais pesados (Pb, Cr, Ni e Zn) em tecidos de Schizothorax plagiostomus. Os tecidos foram extraídos e dissolvidos em ácido perclórico (HClO4) e ácido nítrico (HNO3) com placa de aquecimento. Os metais pesados zinco (Zn), chumbo (Pb), cromo (Cr) e níquel (Ni) foram determinados usando espectrofotômetro de absorção atômica Perkin Elmer 2380. Os resultados mostram grande variação no conteúdo do metal relacionado ao tipo de tecido e locais de amostragem. Uma alta concentração de bioacumulação foi relatada em Charbagh, enquanto a mais baixa, em Odigram: Charbagh > Landakai > Odigram. Da mesma forma, Cr foi o metal pesado mais acumulado, seguido por Pb, Ni e Zn.


Subject(s)
Animals , Water Pollutants, Chemical/analysis , Cyprinidae , Metals, Heavy/analysis , Pakistan , Environmental Monitoring , Rivers , Bioaccumulation
3.
Braz. j. biol ; 81(4): 1081-1094, Oct.-Dec. 2021. tab, graf
Article in English | LILACS | ID: biblio-1153437

ABSTRACT

Abstract Contamination of Lekki lagoon by petrogenic chemicals such as polycyclic aromatic hydrocarbons (PAH) and benzene, toluene, ethylbenzene, and xylene (BTEX) has been widely reported. The study was aimed at investigating the bioaccumulation of PAH and BTEX in Malapterurus electricus collected from Lekki lagoon in Lagos, Nigeria. BTEX was analyzed in the intestine, water, and sediment samples using 8260B Agilent 7890B gas chromatograph coupled to a mass spectrometer (GC-MS). While PAHs were tested in the same media using a gas chromatograph coupled to a flame ionization detector (GC-FID). Histopathological analysis of the fish intestine was conducted using haematoxylin and eosin (H&E) stains. Parasite intensity, antioxidant enzymes, and lipid peroxidation activities were investigated in the fish. The parasitic infection detected in Malapterurus electricus was Electrotaenia malopteruri. The parasite showed weak and no depurative capacities for BTEX and PAH respectively. The decrease in superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) in conjunction with an increase in Malondialdehyde (MDA) characterized relatively higher susceptibility among the male fish. Varieties of tissue injuries increased with the standard length of the fish groups. Results suggest that lengthier and uninfected M. electricus were more susceptible to PAH in Lekki lagoon than the shorter and infected ones. The study demonstrated a promising tendency of the enteric parasite, E. malopteruri to depurate chlorobenzene, ethylbenzene, o-xylene, m+p-xylene, and 1,4-dichlorobenzene from the intestine of its host fish, M. electricus, while PAHs were poorly mediated by the parasite.


Resumo A contaminação da lagoa Lekki por produtos químicos petrogênicos, como hidrocarbonetos aromáticos policíclicos (HAP) e benzeno, tolueno, etilbenzeno e xileno (BTEX), foi amplamente relatada. O estudo teve como objetivo investigar a bioacumulação de HAP e BTEX em Malapterurus electricus, coletados na lagoa Lekki, em Lagos, Nigéria. O BTEX foi analisado no intestino, na água e nas amostras de sedimento usando o cromatógrafo de gás Agilent 7890B 8260B acoplado a um espectrômetro de massa (GC-MS). Já os HAP foram testados no mesmo meio utilizando cromatógrafo gasoso acoplado a detector de ionização de chama (GC-FID). A análise histopatológica do intestino do peixe foi conduzida usando colorações de hematoxilina e eosina (H&E). Intensidade de parasitas, enzimas antioxidantes e atividades de peroxidação lipídica foram investigadas nos peixes. A infecção parasitária detectada em Malapterurus electricus foi Electrotaenia malopteruri. O parasita mostrou fraca e nenhuma capacidade depurativa para BTEX e HAP, respectivamente. A diminuição da superóxido dismutase (SOD), catalase (CAT) e glutationa reduzida (GSH), em conjunto com o aumento do Malondialdeído (MDA), caracterizou a suscetibilidade relativamente maior entre os peixes machos. Variedades de lesões nos tecidos aumentaram com o comprimento padrão dos grupos de peixes. Os resultados sugerem que os M. electricus maiores e não infectados foram mais suscetíveis aos HAP na lagoa Lekki do que os menores e infectados. O estudo demonstrou uma tendência promissora do parasita entérico E. malopteruri de depurar clorobenzeno, etilbenzeno, o-xileno, m + p-xileno e 1,4-diclorobenzeno do intestino de seu peixe hospedeiro, M. electricus, enquanto os HAP foram mal mediados pelo parasita.


Subject(s)
Animals , Male , Parasites , Polycyclic Aromatic Hydrocarbons , Catfishes , Toluene , Xylenes , Benzene/analysis , Benzene Derivatives , Bioaccumulation , Nigeria
4.
Braz. j. biol ; 81(4): 1095-1105, Oct.-Dec. 2021. tab, graf
Article in English | LILACS | ID: biblio-1153430

ABSTRACT

Abstract The exponential rise in the Nigerian population has necessitated the use of agrochemicals for enhanced agricultural yields to meet the ever-rising demand for food. However, agrochemicals such as organochlorine pesticides (OCPs) have caused several devastating health and ecological challenges. The study was therefore aimed at assessing the bioaccumulation of OCPs and the associated parasitological and microbial susceptibility in P. obscura to determine the possible ecological impacts of the chemical. A total of 106 specimens of Parachanna obscura fish species were sampled between July and November 2019 from Lekki Lagoon in Lagos, Nigeria. Four culture media, namely nutrient agar (NA), MacConkay agar (MCA), eosin methylene blue (EMB), and sabouraud dextrose agar (SDA) were employed in microbial culture. These microbes were subjected to ceftazidime, ceftriaxone, cefuroxime, gentamicin, ofloxacin, augmentin, nitrofurantoin, ciprofloxacin, and erythromycin to test for resistance, susceptibility and intermediate statuses before and after curing. OCPs were tested in the water, sediment, and tissues of P. obscura using gas chromatography flame ionization detector (GC-FID). P. obscura sampled in the lagoon had poor growth exponent which was characterized by negative allometry (slenderness) in the sampled fish. Although the incidence of parasitic infection in the fish was not alarming, the situation might be aggravated if the prevalent anthropogenic activities persist, resulting in immunosuppression. Regulation of anthropogenic activities in the catchment area is recommended to forestall the prognosis of health and environmental hazards associated with the agricultural, industrial, pharmaceutical, and municipal activities around the lagoon. Bacteria that conferred the most resistance to the majority of the antibiotics were Staphylococcus sp., Micrococcus sp. Escherichia coli and Klebsiella sp., testing positive to plasmid profile. They conferred high resistance to the antibiotics before plasmid curing but became highly susceptible post- plasmid curing. This implies that the gene for resistance in the bacteria isolates was plasmid-mediated, that is, they were obtained from the environment. In the event of an outbreak of waterborne diseases such as cholera, typhoid, dysentery, and diarrhea, there may be non-response to treatment among the infected inhabitants. The incidence of antibiotic resistance in bacteria colonies recorded in this study is of great public health concern, given the possibility of the antibiotic-resistant bacteria strains being passed to humans through fish consumption, resulting in increased multi-drug resistance in humans. Regulation of anthropogenic activities around the lagoon is recommended to forestall prognosis of health and environmental hazards associated with OCPs from agricultural, industrial, pharmaceutical, and municipal sources.


Resumo O aumento exponencial da população nigeriana exigiu o uso de agroquímicos para aumentar a produção agrícola e, assim, atender à crescente demanda por alimentos. No entanto, agroquímicos como pesticidas organoclorados (OCPs) causaram vários problemas de saúde e ecológicos. Portanto, o estudo teve como objetivo avaliar a bioacumulação de OCPs e a suscetibilidade parasitológica e microbiana associada em Parachanna obscura, a fim de determinar os possíveis impactos ecológicos desse produto químico. Foi amostrado um total de 106 espécimes de P. obscura entre julho e novembro de 2019 da lagoa Lekki, em Lagos, Nigéria. Quatro meios de cultura, como o ágar nutritivo (NA), o ágar MacConkay (MCA), o ágar eosina azul de metileno (EMB) e o ágar sabouraud dextrose (SDA), foram empregados na cultura microbiana. Esses micróbios foram submetidos a ceftazidima, ceftriaxona, cefuroxima, gentamicina, ofloxacina, augmentin, nitrofurantoína, ciprofloxacina e eritromicina para testar resistência, suscetibilidade e status intermediário antes e depois da cura. Os OCPs foram testados na água, sedimentos e tecidos de P. obscura usando um detector de ionização de chama por cromatografia em fase gasosa (GC-FID). Os peixes amostrados de P. obscura da lagoa apresentaram um expoente de crescimento ruim, caracterizado por alometria negativa (esbelteza). Embora a incidência de infecção parasitária nos peixes não tenha sido alarmante, a situação pode ser agravada se as atividades antropogênicas prevalecentes persistirem, resultando em imunossupressão. Recomenda-se a regulamentação de atividades antropogênicas na área de captação para prevenir o prognóstico de riscos à saúde e ecológicos associados a atividades agrícolas, industriais, farmacêuticas e municipais ao redor da lagoa. As bactérias que conferiram maior resistência à maioria dos antibióticos foram Staphylococcus sp., Micrococcus sp., Escherichia coli e Klebsiella sp., com teste positivo para o perfil plasmidial. Elas conferiram alta resistência aos antibióticos antes da cura do plasmídeo, mas se tornaram altamente suscetíveis após a cura dele. Isso implica que o gene de resistência nos isolados de bactérias foi mediado por plasmídeo, ou seja, foi obtido do ambiente. No caso de surtos de doenças transmitidas pela água, como cólera, febre tifoide, disenteria e diarreia, pode haver não resposta ao tratamento entre os habitantes infectados. A incidência de resistência a antibióticos nas colônias de bactérias registradas neste estudo é de grande preocupação para a saúde pública, dada a possibilidade de que as cepas de bactérias resistentes a antibióticos sejam transmitidas aos seres humanos por meio do consumo de peixes, resultando em maior resistência a múltiplas drogas em seres humanos. Recomenda-se a regulamentação de atividades antropogênicas ao redor da lagoa para impedir o prognóstico de riscos à saúde e ecológicos associados aos OCPs de fontes agrícolas, industriais, farmacêuticas e municipais.


Subject(s)
Humans , Animals , Pesticides , Bioaccumulation , Microbial Sensitivity Tests , Escherichia coli , Anti-Bacterial Agents , Nigeria
5.
Rev. bras. ciênc. vet ; 28(4): 225-231, out./dez. 2021. il.
Article in English | LILACS, VETINDEX | ID: biblio-1363787

ABSTRACT

This study has as objective to determine total mercury (Total Hg) levels by atomic absorption spectrophotometry in 134 individuals edible part of Mullus argentinae, in two different fishing areas and two seasons in Rio de Janeiro State. Also, proximate composition was performed. Total Hg results in wet weight basis ranged from 0.0867 to 0.7476 µg.g-1 in muscle; 0.0023 to 0,1034 µg.g-1 in flippers; and 0.0177 to 0.1849 µg.g-1 in skin. Mean evaluated moisture was 73.39%; protein was 18.76%; lipid concentration of 5.36%; carbohydrates of 2.35%; and ashes were 0.85%.Results showed that Total Hg contents was lower than accepted limits established by regulatory organization. Higher averages were observed in muscle (0.2441 µg.g-1) when compared with skin (0.2386 µg.g-1) and flippers (0.0195 µg.g-1). In general, samples collected on summer showed higher values of total Hg when comparing to winter. Regarding beach areas there was no significant difference (p>0.05). We can conclude that this specie should be cautious consumed because of total Hg bioaccumulation characteristics, although neither levels were above limits established.


O objetivo deste estudo foi determinar o teor de mercúrio no tecido comestível de Mullus argentinae, conhecido como peixe trilha, espécie amplamente consumida no Rio de Janeiro, Brasil. Foi determinado o teor de mercúrio total (Hg total) por espectrofotometria de absorção atômica em 134 amostras, coletados em duas áreas e estações climáticas diferentes. Além disso, foi avaliada a composição centesimal das amostras. Os resultados de Hg total em peso úmido variaram de 0,0867 a 0,7476 µg.g-1 no músculo; 0,0023 a 0,1034 µg.g-1 nas nadadeiras; e 0,0177 a 0,1849 µg.g-1 na pele. Os valores médios da composição centesimal foram de 73,30% de umidade, 18,76% de proteína, 5,36% de lipídios, 2,35% de carboidratos e 0,85% de matéria mineral. Os resultados das 134 amostras analisadas demostraram que os teores de Hg Total apresentam concentração inferior aos limites aceitos pelos órgãos reguladores. As maiores médias foram observadas no músculo (0,2441 µg.g-1) quando comparadas à pele (0,2386 µg.g-1) e nadadeiras (0,0195 µg.g-1). Em geral, as amostras coletadas no verão apresentaram maiores valores de Hg total em relação ao inverno. Em relação aos locais de coleta não houve diferença significativa (p> 0,05). Podemos concluir que esta espécie deve ser consumida com cautela devido às características de bioacumulação do Hg total, apesar das médias apresentadas estarem abaixo dos limites estabelecidos pela legislação.


Subject(s)
Animals , Fishes , Bioaccumulation , Mercury , Spectrum Analysis , Fish Proteins/analysis
6.
Braz. j. biol ; 81(3): 822-834, July-Sept. 2021. tab, graf
Article in English | LILACS | ID: biblio-1153390

ABSTRACT

Abstract This study was aimed at determining the concentration of pyrethroid in the surface water, sediment, Weyonia acuminata and Synodontis clarias fish in Lekki lagoon, Lagos, Nigeria. In-situ physicochemical analysis of the surface water was conducted using a calibrated handheld multi-parameter probe (Horiba Checker Model U-10). Intestinal samples from infected and uninfected fish were analyzed for pyrethroid concentrations, microbial colonization, proteins (PRO), superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), malonaldehyde (MDA) and glutathione peroxidase (GPx). The histopathology of infected and uninfected intestinal tissues were analyzed using Haematoxylin and Eosin (H&E) stains and examined under a binocular light microscope (Model 230485). A total of 39 out of 98 S. clarias fish were infected with cestode parasite, Wenyonia acuminate, amounting to 39% parasite prevalence. Among the tested pyrethroids, Cyfluthrin and Alpha -cypermethrin had significant sorption of 1.62 and 3.27 respectively from the aqueous phase to the bottom sediment of the lagoon. Pyrethroid concentration was in the order of sediment > parasite> water > intestine> liver. The cholesterol, triglycerides, and LDL (low density lipids) in the parasite were higher than in the host fish (p<0.05). On the other hand, the fish hepatic protein, high density lipids (HDL) and glucose were higher than the levels in the parasites (p<0.05). There was a high prevalence of gut microbes (30 - 40%), which include Salmonella sp, Escherichia coli, Pseudomonas sp and Bacillus sp among individuals infected with gut Cestodes, Wenyonia sp compared with uninfected individual which had higher gut Staphylococcus sp., Klebsiella sp., and Proteus sp. (10- 40%). among the congeners of pyrethroids analyzed, Cyfluthrin > Alpha-Cyermethrin had significant sorption on the sediment, however unlike a benthopelagic fish, no pyrethroid was accumulated in the S. clarias from the sediment. The fish however accumulated Alpha-Cypermethrin from the aqueous phase. The parasite on the other hand accumulated Bathroid significantly from the surface water and bottom sediment which may be linked to the higher stress levels observed in the parasite than the host fish. The parasite in turn inflicted histological alterations on the host intestine, marked by moderate inflammation of mucosa, alteration of the villi microstructure, moderate stunting of the villous structure and moderate fibrosis of villous structure. The study demonstrated the efficiency of histopathological and microbial analysis in biomonitoring studies enteric parasites and early detection of pyrethroid toxicity respectively compared to bioaccumulation analysis.


Resumo Este estudo teve como objetivo determinar a concentração de piretroide nos peixes de águas superficiais, sedimentos, Wenyonia acuminata e Synodontis clarias na lagoa de Lekki, Lagos, Nigéria. A análise físico-química in situ da água de superfície foi realizada usando uma sonda multiparâmetro manual calibrada (Horiba Checker Modelo U-10). Amostras intestinais de peixes infectados e não infectados foram analisadas quanto a concentrações de piretroides, colonização microbiana, proteínas (PRO), superóxido dismutase (SOD), catalase (CAT), glutationa reduzida (GSH), malonaldeído (MDA) e glutationa peroxidase (GPx). A histopatologia dos tecidos intestinais infectados e não infectados foi analisada usando manchas de Hematoxilina e Eosina (H&E) e examinada sob um microscópio de luz binocular (Modelo 230485). Um total de 39 dos 98 peixes de S. clarias foi infectado com o parasita cestoide Wenyonia acuminata, totalizando 39% de prevalência do parasita. Entre os piretroides testados, ciflutrina e alfa-cipermetrina tiveram sorção significativa de 1,62 e 3,27, respectivamente, da fase aquosa ao sedimento de fundo da lagoa. A concentração de piretroides estava na ordem de sedimentos > parasita > água > intestino > fígado. O colesterol, os triglicerídeos e o LDL (lipídios de baixa densidade) no parasita foram maiores que no peixe hospedeiro (p < 0,05). Por outro lado, a proteína hepática dos peixes, os lipídios de alta densidade (HDL) e a glicose foram superiores aos níveis nos parasitas (p < 0,05). Houve uma alta prevalência de micróbios intestinais (30-40%), incluindo Salmonella sp., Escherichia coli, Pseudomonas sp. e Bacillus sp. entre indivíduos infectados no intestino com o parasita cestoide Wenyonia sp. em comparação com indivíduos não infectados com Staphylococcus sp., Klebsiella intestinal sp. e Proteus sp. (10-40%). Entre os congêneres dos piretroides analisados, ciflutrina > alfa-cipermetrina teve sorção significativa no sedimento, porém, diferentemente de um peixe bentopelágico, nenhum piretroide foi acumulado no S. clarias do sedimento. No entanto, os peixes acumularam alfa-cipermetrina a partir da fase aquosa. O parasita, por outro lado, acumulou Bathroid significativamente da água superficial e do sedimento do fundo, o que pode estar relacionado aos níveis mais altos de estresse observados no parasita do que no peixe hospedeiro. O parasita, por sua vez, causou alterações histológicas no intestino hospedeiro, marcadas por inflamação moderada da mucosa, alteração da microestrutura das vilosidades, atrofia moderada da estrutura das vilosidades e fibrose moderada da estrutura das vilosidades. O estudo demonstrou a eficiência da análise histopatológica e microbiana nos estudos de biomonitoramento de parasitas entéricos e detecção precoce da toxicidade dos piretroides, respectivamente, em comparação à análise de bioacumulação.


Subject(s)
Animals , Parasites , Pyrethrins , Water Pollutants, Chemical/analysis , Cestoda , Bioaccumulation , Nigeria
7.
Neotrop. ichthyol ; 19(3): e200155, 2021. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1340228

ABSTRACT

In South America, mercury contamination due to gold mining operations is a threat to both biodiversity and human health. We examined mercury (Hg) concentrations in fishes that constitute important subsistence fisheries from mined and non-mined tributaries in the middle Mazaruni River, Guyana. Mercury concentrations and trophic food web structure (based on carbon and nitrogen stable isotopes) were characterized for primary basal sources and 39 fish species representing seven trophic guilds. Fishes collected at mined sites had higher mercury concentrations; piscivores and carnivores had the highest Hg concentrations and exhibited significant Hg biomagnification. Our results showed that medium- to large-bodied fishes commonly eaten by local people contained Hg values that exceed the World Health Organization (WHO) criteria, and pose a health concern for riverine communities along the Mazaruni River that depend on fish as their main source of protein. Further research to determine the sources of Hg contamination and how it affects human health in this neotropical river must become a top priority. In addition, more research on how Hg contamination impacts the fishes themselves and overall aquatic biodiversity is also needed in the Mazaruni River which has both high fish endemism and diversity.(AU)


Na América do Sul, a contaminação por mercúrio devido às operações de mineração de ouro é uma ameaça à biodiversidade e à saúde humana. Nós examinamos as concentrações de mercúrio (Hg) em peixes que constituem importantes pescarias de subsistência em afluentes minerados e não minerados no médio rio Mazaruni, Guiana. As concentrações de mercúrio e a estrutura trófica da teia alimentar (baseada em isótopos estáveis ​​de carbono e nitrogênio) foram caracterizadas para fontes basais primárias e 39 espécies de peixes representando sete guildas tróficas. Os peixes coletados em locais minerados tiveram maiores concentrações de mercúrio; piscívoros e carnívoros tiveram as maiores concentrações de Hg e exibiram biomagnificação significativa de Hg. Nossos resultados mostraram que peixes de corpo médio a grande comumente consumidos pela população local continham valores de Hg que excedem os critérios da Organização Mundial de Saúde (OMS) e representam uma preocupação para a saúde das comunidades ribeirinhas ao longo do rio Mazaruni que dependem dos peixes como sua principal fonte de proteína. Outras pesquisas para determinar as fontes de contaminação por Hg e como isso afeta a saúde humana neste rio neotropical devem se tornar uma prioridade. Além disso, mais pesquisas sobre como a contaminação por Hg impacta os próprios peixes e a biodiversidade aquática em geral também são necessárias no rio Mazaruni, que tem alto endemismo e diversidade de peixes.(AU)


Subject(s)
Animals , Chemical Contamination , Fishes/physiology , Mercury/toxicity , Food Chain , Bioaccumulation , Mercury Isotopes/chemistry
8.
Braz. j. biol ; 81(2): 499-507, 2021. tab, graf, ilus
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1153369

ABSTRACT

Increased agricultural production has been increased use of pesticides worldwide, which poses a threat to both human and environmental health. Recent studies suggest that several non-target organisms, from bees to mammals, show a wide variety of toxic effects of pesticides exposure, including impaired behavior, development and reproduction. Among mammals, bats are usually a neglected taxon among ecotoxicological studies, although they play important ecological and economical roles in forest ecosystems and agriculture through to seed dispersal and insect population control. Considering their wide variety of food habits, bats are exposed to environmental pollutants through food or water contamination, or through direct skin contact in their roosting areas. In order to better understand the risk posed by pesticides to bats populations, we compiled studies that investigated the main toxicological effects of pesticides in bats, aiming at contributing to discussion about the environmental risks associated with the use of pesticides.


O aumento da produção agrícola tem levado ao aumento do uso de pesticidas em todo o mundo, o que representa uma ameaça para a saúde humana e ambiental. Estudos recentes sugerem que vários organismos não-alvo, de abelhas a mamíferos, apresentam uma grande variedade de efeitos tóxicos após a exposição aos pesticidas a pesticidas, incluindo alterações de comportamento, no desenvolvimento e na reprodução. Entre os mamíferos, os morcegos geralmente são negligenciados entre os estudos ecotoxicológicos, embora desempenhem importantes papéis ecológicos e econômicos nos ecossistemas florestais e na agricultura por meio do controle de dispersão de sementes e de populações de insetos. Considerando sua ampla variedade de hábitos alimentares, eles estão expostos a poluentes ambientais através da contaminação de alimentos ou água, ou através do contato direto com a pele em suas áreas de descanso. Para entender melhor o risco que os agrotóxicos representam para as populações de morcegos, compilamos estudos que investigaram os principais efeitos toxicológicos de agrotóxicos em morcegos, visando à discussão sobre os riscos ambientais associados ao uso de agrotóxicos.


Subject(s)
Animals , Pesticides/toxicity , Pyrethrins/analysis , Chiroptera/physiology , Environmental Pollutants/toxicity , Insecticides, Organochlorine/analysis , Bees , Ecosystem , Agriculture , Bioaccumulation
9.
Acta amaz ; 50(2): 142-148, abr - jun. 2020.
Article in English | LILACS | ID: biblio-1118376

ABSTRACT

This is the first study to investigate mercury (Hg) contamination in felid species in the Brazilian Amazon. We collected 26 fur samples from wild felids of four species (Puma concolor, Panthera onca, Leopardus pardalis and Leopardus wiedii) occurring in the Mamirauá and Amanã sustainable development reserves, in the state of Amazonas. Samples were from museum specimens, except for five P. onca samples collected from free-living individuals. Total Hg concentrations ranged from 0.12 to 48.1 µg g-1. Concentrations of Hg did not differ significantly between museum specimens and live individuals of P. onca, but varied significantly among species, with significantly higher concentrations for P. onca and L. pardalis, which could be related to factors such as diet and habitat. (AU)


Subject(s)
Metals, Heavy , Bioaccumulation , Mammals , Amazonian Ecosystem , Mercury/toxicity
10.
Electron. j. biotechnol ; 37: 56-60, Jan. 2019. tab
Article in English | LILACS | ID: biblio-1051261

ABSTRACT

Heavy metals are natural elements in the Earth's crust that can enter human food through industrial or agricultural processing, in the form of fertilizers and pesticides. These elements are not biodegradable. Some heavy metals are known as pollutants and are toxic, and their bioaccumulation in plant and animal tissues can cause undesirable effects for humans; therefore, their amount in water and food should always be under control. The aim of this study is to investigate the conditions for the bioremediation of heavy metals in foods. Various physical, chemical, and biological methods have been used to reduce the heavy metal content in the environment. During the last decades, bioremediation methods using plants and microorganisms have created interest to researchers for their advantages such as being more specific and environmentally friendly. The main pollutant elements in foods and beverages are lead, cadmium, arsenic, and mercury, which have their own permissible limits. Among the microorganisms that are capable of bioremediation of heavy metals, Saccharomyces cerevisiae is an interesting choice for its special characteristics and being safe for humans, which make it quite common and useful in the food industry. Its mass production as the byproduct of the fermentation industry and the low cost of culture media are the other advantages. The ability of this yeast to remove an individual separated element has also been widely investigated. In countries with high heavy metal pollution in wheat, the use of S. cerevisiae is a native solution for overcoming the problem of solution. This article summarizes the main conditions for heavy metal absorption by S. cerevisiae.


Subject(s)
Saccharomyces cerevisiae/metabolism , Biodegradation, Environmental , Food Industry , Metals, Heavy/metabolism , Arsenic , Yeasts , Cadmium , Contaminant Removal , Absorption , Bioaccumulation , Lead , Mercury
11.
Biosci. j. (Online) ; 35(4): 1237-1244, july/aug. 2019. graf
Article in English | LILACS | ID: biblio-1048926

ABSTRACT

Industrialization has added extremely toxic metalloid arsenic into the environment which at high concentration severely threatens the biota. Naturally, some microbes possess the ability to bio-accumulate metals and also to transform arsenite (As III) a toxic form to a non-toxic arsenate As V. The present study aimed to isolate arsenic resistant bacterias from the arsenic contaminated soil and water. Among eleven bacterial isolates, three FAs 1, 4 and 9 exhibited tolerance against sodium arsenite at 100mM concentration by achieving growth of 7.48×109,1.57×109 and 2.23×109 C.F.U./ml, respectively. Optimization at differentconditions such as temperature, pH and arsenic concentration revealed high arsenic tolerance from isolate FAs 4 (5.33×108) at 37°C and FAs 1 (4.43×108 C.F.U./ml) at pH 7. Arsenic resistance at optimum conditions for the bacterial strains FAs 1, FAs 4 and FAs 9 showed maximum growth at 80mM concentration of arsenite. These bacterial isolates did not show redox ability to oxidize arsenite As III to arsenate As V. However bacterial isolates FAs 1, FAs 4 and FAs 9 were able to accumulate arsenic 39.16, 148 and 125 µ g/L on the 4th, 3rd and 5thday of incubation, respectively. The isolates FAs 1, FAs 4 and FAs 9 were identified as Gram negative non endospore forming rods. In future, these novel isolates possess a great potential in biotechnology field, as bioremediation of arsenic contaminated soil and water can be done by employing arsenic accumulating bacteria which is an eco-friendly and cost effective method.


A industrialização adicionou arsênico metalóide extremamente tóxico ao ambiente que, em alta concentração, ameaça severamente a biota. Naturalmente, alguns micróbios possuem a capacidade de bio-acumular metais e também transformar arsenito (As III) uma forma tóxica a um arsenato não-tóxico Como V. O presente estudo visa o isolamento de bactérias resistentes ao arsênico do solo contaminado com arsênico e água . Entre onze isolados bacterianos, três FAs 1, 4 e 9 exibiram tolerância à concentração de 100 mM de arseatura de sódio, obtendo crescimento de 7,48 × 109,157 × 109 e 2,23 × 109 C.F.U./ml, respectivamente. Otimização em diferentes condições como temperatura, pH e concentração de arsênio revelaram alta tolerância ao arsênico do isolado FAs 4 (5,33 × 108) a 37 ° C e FAs 1 (4,43 × 108 UFC / ml) em pH 7. Resistência ao arsênico em condições ótimas para as cepas bacterianas FAs 1, FAs 4 e FAs 9 apresentaram crescimento máximo na concentração de 80 mM de arsenito. Estes isolados bacterianos não mostraram capacidade redoxpara oxidar o arsenito As III para arseniar como V. No entanto, os isolados bacterianos FAs 1, FAs 4 e FAs 9 foram capazes de acumular arsênico 39,16, 148 e 125 µ g / L no 4º, 3º e 5º dia de incubação, respectivamente. Os isolados FAs 1, FAs 4 e FAs 9 foram identificados como bastonetes gram-negativos não endoscópicos. No futuro, esses novos isolados possuem um grande potencial no campo da biotecnologia, já que a biorremediação de solo e água contaminados com arsênico pode ser feita empregando-se bactérias que acumulam arsênico, o que é um método ecologicamente correto e econômico.


Subject(s)
Arsenic , Biodegradation, Environmental , Environmental Pollution , Bioaccumulation
12.
Braz. arch. biol. technol ; 62: e19180487, 2019. tab, graf
Article in English | LILACS | ID: biblio-1055399

ABSTRACT

Abstract: The aim of this study is to explain the biological response and rhizofiltration capacity of Pistia stratiotes, which is an aquatic macrophyte, in alleviating heavy metal stress. In our study, Pistia species were exposed to Nickel (Ni) at different concentrations over seven days. The potential of the aquatic macrophytes in accumulating heavy metals in the water and in removing them from the environment was evaluated by determining the bio-concentration factors (BCF). Selected biological parameters in the leaves of Pistia stratiotes, including metal accumulation, photosynthetic pigment amount, lipid peroxidation activity, and growth rates were measured at the end of the seven-day period. The highest amount of Ni accumulation in P. stratiotes occurred at a concentration of 20 mg l-1. The amount of chlorophyll a (chl a) in P. stratiotes reached a value of 0.087 mg g-1 at the Ni concentration of 20 mg l-1. The relative growth rate (RGR) of P. stratiotes showed a negative correlation with the increases in the concentration levels of the metal. Malondialdehyde (MDA) levels increased to 8.214 nmol/g at the concentration of 20 mg l-1, depending on Ni concentration and time. In our study, the use of P. stratiotes has been determined to be an appropriate plant as an effective Ni accumulator to be utilized with the purpose of rhizofiltration.


Subject(s)
Biodegradation, Environmental , Metals, Heavy , Araceae , Bioaccumulation
13.
Braz. arch. biol. technol ; 62: e19180523, 2019. tab
Article in English | LILACS | ID: biblio-1055386

ABSTRACT

Abstract: The Paranhana River, located in Southern Brazil, is one of the major tributaries of the Sinos River basin and receives mainly industrial and domestic effluents. In the present study, water physicochemical and microbiological analyses, condition factor, micronucleus test, gill histopathology and metal bioaccumulation in the muscle of the native fish Bryconamericus iheringii collected at two sites (S1 and S2) of the Paranhana River under different degrees of anthropogenic pressures were assessed in four sampling campaigns. Data from water quality parameters, condition factor, mucous cells proliferation in fish gills and bioaccumulation of chromium and manganese in muscle evidenced higher impacts at S2, whereas a higher genotoxic potential was observed at S1. Gill histopathological alterations were found in fish captured at both sampling sites. Temporal variations in all biomarkers analyzed and bioaccumulation of manganese and nickel were observed at S1, whereas only variations in condition factor, gill alterations and bioaccumulation of manganese and aluminum were found at S2. Our study evidences that S1 is under minor anthropogenic impacts and that the high urbanization at S2 reflects in a poor water quality. Nonetheless, the human consumption of fish from the Paranhana River should be avoided given the high concentrations of cadmium, chromium and lead.


Subject(s)
Water/analysis , Biomarkers , Bioaccumulation , Brazil , Micronucleus Tests/instrumentation
14.
Braz. arch. biol. technol ; 61: e18160777, 2018. tab, graf
Article in English | LILACS | ID: biblio-974113

ABSTRACT

ABSTRACT This study aims to specify the amount of ten heavy metals (Al, Cr, Mn, Ni, Cu, Zn, As, Cd, Hg, Pb) in water, sediment and Enteromorpha intestinalis samples gathered from Kadin Creek in seasonal periods in 2011 and 2012 and to reveal bioaccumulation capability of this macrophytic algae. In this regard, heavy metal concentrations in the gathered samples were determined first with mineralization and then via inductively coupled plasma mass spectroscopy (ICP-MS) method. Findings suggested that algae could be used as an indicator in freshwater ecosystems in terms of studied heavy metals. With regard to bioconcentration factor values, in terms of water, algae accumulated aluminum the most and cadmium the least (Al > Cu > As > Zn > Cr > Mn > Ni > Pb > Hg > Cd), in terms of sediment, it accumulated mercury the most and aluminum the least (Hg > Cd > As > Zn > Pb > Mn > Ni > Cr > Cu > Al). The highest rate of heavy metal concentration in algae was observed in summer when contaminants in water and dynamics of plant development increased. It was also observed that the mean mercury and cadmium concentrations exceeded the maximum residue limit values.


Subject(s)
Seaweed , Water Samples , Metals, Heavy/analysis , Bioaccumulation
15.
Rev. Fac. Cienc. Méd. Univ. Cuenca ; 35(2): 55-59, Diciembre 2017.
Article in Spanish | LILACS | ID: biblio-998921

ABSTRACT

El desarrollo industrial de las últimas décadas, ha traído como consecuencia la acumulación de sustancias que provocan daño en el medio ambiente y la salud. Actualmente, se han detectado sustancias que siempre han estado presentes, pero que han pasado desapercibidas por falta de técnicas adecuadas para su identificación, a las cuales se les llama "contaminantes emergentes", entre ellas se encuentran productos como:fármacos, plaguicidas, cosméticos, artículos de limpieza y aseo personal entre otros. Este artículo presenta una revisión de la evidencia disponible y la importancia del estudio de los contaminante emergentes y su impacto en el medio ambiente y en la salud. Los contaminantes emergentes, son sustancias que a pesar de que pueden ser biodegradables, son muy peligrosas para el ambiente y el organismo humano debido a su bioacumulación y persistencia. Otro grave problema radica en el hecho de que actualmente, las plantas de tratamiento de aguas residuales, no los eliminan, por lo que es importante el desarrollo de nuevas tecnologías de depuración.


The industrial development of the last decades has caused the accumulationof substances that damage the environment and health.Recently, somesubstances have been detected, they have always been present, but theyhave gone unnoticed due to a lack of adequate techniques for their iden-tification, which are called "emerging contaminants", including productssuch as drugs, pesticides, cosmetics, cleaning and personal hygiene items,among others.This article presents a review of the available evidence and the importanceof the study of emerging contaminants and their impact on the environ-ment and health. The emerging contaminants are substances that although they can be biodegradable, are very dangerous forthe environment and the human organism due totheir bioaccumulation and persistence.Another seriousproblem lies in the fact that the current water treat-ment plants do not eliminate them, so the develop-ment of new purification technologies is important.


Subject(s)
Hazardous Waste , Toxic Substances , Environmental Pollutants , Bioaccumulation , Environment
16.
Pesqui. vet. bras ; 37(10): 1146-1152, out. 2017. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-895329

ABSTRACT

Os elementos químicos, em sua maioria, encontram-se em ciclos bioquímicos e geoquímicos fechados e em concentrações que não causam efeitos nocivos aos organismos. Contudo, ações antrópicas aceleradas promovem alterações ambientais, como o aumento no aporte de contaminantes. Com essas informações, o presente trabalho buscou caracterizar a presença aos elementos traços em duas espécies de serpentes comuns na região sudeste, Boa constrictor e Bothrops jararaca. Os exemplares de B. constrictor (n=18) foram provenientes de atropelamentos ocorridos no trecho da Rodovia ES-060 do Km 0 ao Km 67,5. Os exemplares de B. jararaca (n=18) foram capturados por fazendeiros na zona rural da região serrana do Espírito Santo. Foram analisados 1 grama de fragmento de rim, de espécimes necropsiados. Os rins coletados foram digeridos com mistura ácida (HNO3;HCl; 1:1) a 300oC, 40min e a quantificação de microelementos (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb e Zn) foi realizada por espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). Não foram observadas diferenças significativas entre machos e fêmeas, exceto para Cromo nas B. constrictor (p=0,03), com média de 1,6595 nas concentrações de Cr nas fêmeas e 0,2896 em machos. Contudo, quando foram comparadas as diferentes espécies de serpentes, diferentes concentrações foram encontradas, para todos os elementos determinados, com destaque para o Ferro com uma concentração de 106,2mg/g em B. constrictor e 120,3mg/g em B. jararaca, provavelmente por esses animais virem de áreas próximas à portos de minério de ferro. A concentração de Zinco em B. constrictor foi de 1261,8mg/g e em B. jararaca foi de 28,4mg/g. O presente estudo indica que as serpentes analisadas, que habitam as regiões da Grande Vitória e serrana do Espírito Santo apresentam elevadas concentrações dos microelementos Zn e Fe.(AU)


Chemical elements are mostly involved in biochemical and geochemical cycles in concentrations which are harmless for organisms. However, accelerated human actions promote environmental changes such as the increase in contaminant intake. With this information, this study aimed to characterize the presence of trace elements in two snake species common in Southeastern Brazil, Boa constrictor and Bothrops jararaca. Copies of B. constrictor (n=18) were from pedestrian accidents which occurred on Highway stretch ES-060 from Km 0 to Km 67.5. Copies of B. jararaca (n=18) were captured by farmers in a rural mountainous area of Espíirito Santo State, Brazilo. They were analyzed 1 kidney fragment grass, autopsied specimens. Harvested kidneys were digested with acid mixture (HNO3 e HCl 1:1) at 300°C, 40 min and quantification of microelementos (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were determined by spectrometric optical emission with inductively coupled plasma (ICP OES). significant differences between males and females were observed, except for Chrome in B. constrictor (p=0.03), with an average of 1.6595 in Cr concentration of females and 0.2896 in males. However, when different species of snakes were compared, different concentrations were found for all elements, especially iron with a concentration of 106.2mg/g in B. constrictor and 120.3mg/g in B. jararaca; probably these animals came from areas near iron ore ports. The concentration of zinc in B. constrictor was 1261.8mg/g and in B. jararaca 28,4mg/g. This study indicates that the analyzed snakes, which inhabit the regions of Greater Victoria and the mountainous region of the State of Espírito Santo have high concentrations of the microelements Zn and Fe.(AU)


Subject(s)
Animals , Snakes , Trace Elements/poisoning , Bothrops , Bioaccumulation , Environmental Pollution
17.
Biosci. j. (Online) ; 32(3): 627-641, may/june 2016. tab
Article in English | LILACS | ID: biblio-965502

ABSTRACT

What are the molecular properties of agricultural chemicals, how do they function and why should they be studied? How do they affect the agroecosystem and how are they linked to application technologies? These questions arise due to the lack of information in the literature about this issue and form the basis of the current review. In general, a better understanding of the physical-chemical characteristics of agricultural chemicals makes it possible to improve their efficiency of application, consequently reducing losses and maintaining the integrity of the environment. These points underscore the importance of this subject, which has been deeply discussed in Europe. In Brazil, there are few studies that examine the physicochemical properties of pesticides at the molecular level and virtually none that examine their impact. Thus, the current study attempts to clarify the concepts, applications, and interactions of the physical-chemical properties of agricultural chemicals with the environment. The trade secrets associated with these molecules are essential to the agrochemical industry, which certainly restricts scientific publications on the topic. Nevertheless, these properties are linked to the products' mobility in the soil, disassociation in water, bioaccumulation, persistence, and durability in the environment and on the target. In summary, the more mobile and persistent a molecule is, the greater its potential for seepage and leaching and, consequently, the greater its potential for contaminating surface, subsurface, and ground water. This type of molecule becomes more environmentally aggressive if it bioaccumulates readily and degrades slowly. It should be noted that proper handling of agrochemicals depends not only on an understanding of their molecular properties, but also on their safe application. These concepts are essential for the successful promotion and sustainable use of these products in rural areas.


Quais são, como e por que estudar as propriedades moleculares de agrotóxicos? Quais seus impactos no agroecossistema? Como associá-las à tecnologia de aplicação? Estes questionamentos são decorrentes da escassez literária sobre o tema e são a base argumentativa desta revisão. De maneira geral, o conhecimento das características físico-químicas dos agrotóxicos possibilita aumentar a eficiência e reduzir as perdas dos produtos no ato da aplicação, o que se associa às predições de sucesso desta aplicação e, consequentemente, à manutenção da integridade ambiental. Estes aspectos ressaltam a importância do tema, há muito discutido na Europa. No Brasil, são poucas as pesquisas relacionadas às propriedades físico-químicas dos agrotóxicos, intrínsecas a cada molécula, e praticamente inexistentes as discussões sobre seus impactos. Por isto, esta revisão visa elucidar conceitos, aplicações e interações das propriedades físico-químicas de agrotóxicos com o ambiente. Indiscutivelmente, os segredos comerciais relacionados às moléculas são o grande arcabouço da indústria de agrotóxico, o que certamente restringe publicações científicas na área. Contudo, sabe-se que estas propriedades estão associadas à mobilidade dos produtos no solo, sua dissociação em água, bioacumulação, persistência e durabilidade no ambiente e no alvo. Em suma, quanto mais móvel e persistente uma molécula, maior seu potencial de percolação e lixiviação, consequentemente, maior a sua periculosidade de contaminação de águas subterrâneas, subsuperficiais e superficiais. Esta molécula torna-se mais agressiva ambientalmente se possuir elevado potencial de bioacumulação e baixa degradação no meio. Cabe salientar que o correto manejo dos agrotóxicos depende não somente do conhecimento de suas propriedades moleculares, mas de uma


Subject(s)
Proline , Agrochemicals , Bioaccumulation
18.
Rev. MVZ Córdoba ; 20(3): 4754-4765, Sept.-Dec. 2015. ilus, tab
Article in English | LILACS, COLNAL | ID: lil-769238

ABSTRACT

Objective. The aim of this study was to monitor the total mercury (T-Hg) concentrations in fish from the Urrá reservoir, after impoundment. Materials and methods. Five fish species at different trophic levels were sampled from 2004 to 2009 and analyzed by cold-vapor atomic absorption spectroscopy for T-Hg concentrations in muscle tissue. Water quality parameters were evaluated. Results. The highest (1.39±0.69 µg/g ww) and lowest (0.15±0.02 µg/g ww) T-Hg concentrations were detected in Hoplias malabaricus (piscivorous) and Cyphocharax magdalenae (iliophagous/detritivorous) respectively, whereas Leporinus muyscorum (omnivorous) had an intermediate level (0.40±0.11 µg/g ww). The organic matter content in the water increased with time and depth, whereas dissolved oxygen and pH decreased. A covariance analysis (with fish length as a covariate) shows a steady increase of T-Hg levels in all the studied species after impoundment. Conclusions. The T-Hg concentrations in the evaluated fish species, increased after impoundment. The water quality variables showed conditions favoring Hg methylation and its biomagnification, this last was evident in the fish food chain of the reservoir.


Objetivo. El objetivo de este estudio fue monitorear las concentraciones de mercurio total (Hg-T) en peces del embalse Urrá después del represamiento. Materiales y métodos. Cinco especies de peces de diferentes niveles tróficos fueron muestreadas de 2004 a 2009 y analizadas por espectroscopia de absorción atómica para las concentraciones de Hg-T en tejido muscular. Se evaluaron parámetros de calidad de agua. Resultados. Las mayores (1.39±0.69 µg/g ph) y menores (0.15±0.02 µg/g ph) concentraciones de Hg-T fueron detectadas en Hoplias malabaricus (piscívoro) y Cyphocharax magdalenae (iliófago/detritívoro) respectivamente, mientras que Leporinus muyscurum (omnívoro) tuvo un nivel intermedio (0.40±0.11 µg/g ph). El contenido de materia orgánica en el agua se incrementó con el tiempo y la profundidad, mientras que el oxígeno disuelto y el pH disminuyeron. Un análisis de covarianza (con la longitud del pez como covariante) mostró un incremento sostenido de los niveles de Hg-T en todas las especies evaluadas después del represamiento. Conclusiones. Las concentraciones de Hg-T en las especies de peces evaluadas, incrementaron después del represamiento. Las variables de calidad de agua mostraron condiciones favorables para la metilación del Hg y su biomagnificación, estos último fue evidente en la cadena alimenticia de los peces del embalse.


Subject(s)
Feeding Behavior , Bioaccumulation , Food Chain
19.
Article in Spanish | LILACS | ID: lil-757883

ABSTRACT

Se presenta el caso de una paciente de 28 años, con tratamiento ortodóncico activo, que acudió a consulta odontológica por motivos estéticos. Luego del examen intraoral se le diagnosticó agrandamiento gingival y exostosis maxilar. El plan de tratamiento consistió en cirugía estética periodontal y exéresis de la exostosis. Durante el tratamiento quirúrgico se tomaron muestras de encía, saliva y hueso alveolar, previo consentimiento informado. Una vez procesadas las muestras se midieron las concentraciones de níquel en ng/ml mediante espectrofotometría de absorción atómica; el promedio de dichas concentraciones en cada una de las muestras fueron: 986,4 ng/ml en saliva, 779,5 ng/ml en hueso y 620,5 ng/ml para el caso de la encía. La acumulación de níquel evidenciada en cada una de las muestras resulta de especial interés, pues la exposición a metales contenidos en la aparatología ortodóncica constituye actualmente un importante tema de investigación.


A case is reported of a 28-year-old female patient, with active orthodontic treatment, who was treated in the dental practice for aesthetic reasons. The diagnosis was gingival overgrowth, induced by orthodontic treatment, and maxillary exostosis. The treatment consisted of periodontal cosmetic surgery and removing the exostosis. During surgery, samples of gingiva, saliva and alveolar bone were obtained. Before take the samples, the patient signed an informed consent. Nickel concentrations in ng/mL were measured by atomic absorption spectrophotometry. The mean nickel concentration in the samples were: 986.4 ng/ml in saliva, 779.5 ng/ml in alveolar bone, and 620.5 ng/ml in the case of gingiva. The high accumulation of nickel observed in each sample type is of particular interest because exposure to metals contained in orthodontic appliances is currently an important public health problem in dentistry.


Subject(s)
Humans , Adult , Female , Orthodontic Appliances/adverse effects , Nickel/analysis , Nickel/adverse effects , Bioaccumulation , Gingiva/pathology , Gingiva/chemistry , Bone and Bones/pathology , Bone and Bones/chemistry , Spectrophotometry, Atomic , Saliva/chemistry
20.
Biosci. j. (Online) ; 30(4): 1158-1167, july/aug. 2014. ilus, tab
Article in Portuguese | LILACS | ID: biblio-967545

ABSTRACT

O trabalho objetivou monitorar a bioacumulação de Cd, Pb e Cr na tilápia do Nilo e retenção no sedimento da caixa de coleta e no solo de viveiros com administração de probióticos na ração. A dieta foi composta de ração comercial peletizada, para alevinos e probióticos liofilizados incluídos na dieta utilizando 2% de óleo vegetal, constituindo de: ração isenta de probióticos (Isento); ração + 0,5% de B. cereus var. Toyoi (ração + B. cereus); ração + 0,5% de B. subtilis C-3102 (ração + B. subtilis); ração + 0,25% de B. cereus var. Toyoi + 0,25% de B. subtilis C-3102 (ração + B. cereus + B. subtilis). Amostragens de ração, filé, pele, brânquias, fígado, carcaça, solo e sedimento da caixa de coleta dos viveiros foram realizadas para a determinação de metais pesados tóxicos por digestão nitro perclórica, e, espectrometria de absorção atômica. Não houve diferença significativa (p>0,05) nos teores dos metais observados nos tecidos analisados dos juvenis alimentados com diferentes combinações de probiótico e ração. Teores de Pb no filé foram superiores ao preconizado pela legislação. Teores de Cr foram detectados somente na pele dos juvenis. O teor de Pb do solo no final do cultivo (71,15 mg kg-1) foi maior (p<0,05) que o encontrado inicialmente (49,10 mg kg-1) e o Cr no sedimento da caixa de coleta (29,95 mg kg-1) foi maior (p<0,05) que o encontrado no solo (18,4 mg kg-1). A adição de probióticos não tem efeito sobre a bioacumulação de metais em juvenis, e sobre a retenção no solo e sedimento.


The study aimed to monitor the bioaccumulation of Cd, Pb and Cr in the Nile tilapia and sediment retention in the collection box in the ground and nursery with administration of probiotics in the ration. The diet consisted of commercial pelleted ration to fingerlings and probiotics included in the diet using 2% vegetable oil, constituting of: diet free of probiotics (Exempt); ration + 0.5% B. cereus var. Toyoi (ration + B. cereus); ration + 0.5% B. subtilis C-3102 (ration + B. subtilis); ration + 0.25% B. cereus var. Toyoi + 0.25% B. subtilis C-3102 (ration + B. cereus + B. subtilis). Samples of ration, filet, skin, gills, liver, carcass, soil and sediment of the collection box of the ponds were performed for the determination of toxic heavy metals by nitro perchloric digestion, and atomic absorption spectrometry. There was no significant difference (p>0.05) observed in the levels of metals in the tissues analyzed for juveniles fed different combinations of probiotic and ration. Lead levels in the filet were greater than recommended by law. Levels of Cr were detected only in the skin of the juveniles. The level of the Pb content of soil at the end of cultivation (71.15 mg kg-1) was higher (p<0.05) than that found initially (49.10 mg kg-1) and the Cr in the sediment of the collection box (29.95 mg kg-1) were greater (p<0.05) than that found in the soil (18.4 mg kg-1). The addition of probiotics has no effect on the bioaccumulation of metals in juveniles, and on the retention in the soil and sediment.


Subject(s)
Bacillus cereus , Bacillus subtilis , Bioaccumulation , Metals, Heavy , Probiotics , Cichlids
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