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1.
Chemosphere ; 262: 127788, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182082

RESUMO

Lead (Pb) interferes with various bodily functions. Although high blood Pb (Pb-B) levels in residents from Kabwe, Zambia have been reported, the accumulation pattern of other metals remains unknown. The study was designed to determine the Pb-B, blood cadmium (Cd-B), and zinc (Zn-B) values of 504 representative samples from Kabwe, as well as the potential associated adverse health effects. The Pb-B level ranged from 0.79 to 154.75 µg/dL and generally increased in areas near the mine. A significant elevation of Cd-B was observed in two areas (0.37 ± 0.26 and 0.32 ± 0.30 µg/L) where the two highest mean Pb-B levels were recorded. By contrast, the Zn-B values did not differ greatly with respect to area. Some blood biochemical parameters relating to hepatic and renal functions were out of the normal range in approximately 20-50% of studied adult participants. The δ-aminolevulinic acid dehydratase (δ-ALAD) activity was significantly inhibited in the two areas contaminated by Pb and Cd. A significant negative relationship was observed between metal levels and clinical parameters, e.g., between Pb-B and δ-ALAD for all the age categories and between Cd-B and the estimated glomerular filtration rate for all the age categories except 0-4 years. The elevated Cd-B in areas near the mine relative to the other areas suggested the potential adverse health effects of Cd and/or the interaction of Pb and Cd. A significant association of metal levels with clinical parameters also indicated the effects of metal exposure on hematopoietic, hepatic, and renal systems.


Assuntos
Exposição Ambiental/análise , Poluentes Ambientais/análise , Metais/análise , Adulto , Cádmio/análise , Coleta de Dados , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental/métodos , Taxa de Filtração Glomerular , Humanos , Fígado/química , Registros , Valores de Referência , Adulto Jovem , Zâmbia , Zinco
2.
J Vet Med Sci ; 81(11): 1575-1579, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31447459

RESUMO

Dichlorodiphenyltrichloroethane (DDT) is an organochlorine insecticide that has been used for indoor residual spraying for the control of mosquito-borne diseases including malaria. However, due to its toxicity and environmental persistence, there are concerns about its potential deleterious effects in humans and wildlife. Therefore, the current study aimed to monitor and estimate the level of DDTs in human communities. The accumulation of DDT and its metabolites was evaluated in house rat (as sentinel) livers collected in an area where DDT was sprayed. DDTs were measured using a gas chromatography / Electron Capture Detector. The results revealed high concentrations of DDTs in the rat livers and the levels of DDTs were similar to findings reported from the same area in 2014.


Assuntos
DDT/química , Inseticidas/química , Fígado/química , Malária/prevenção & controle , Controle de Mosquitos/métodos , Animais , DDT/farmacologia , Poluentes Ambientais/química , Feminino , Insetos Vetores , Inseticidas/farmacologia , Masculino , Ratos , Vigilância de Evento Sentinela
3.
Ecotoxicology ; 27(9): 1203-1216, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30173332

RESUMO

Organochlorine pesticides are highly persistent in aquatic ecosystems. Amphibians, specifically anurans, play an intricate part in the aquatic food web, and have very permeable skin which makes them prone to bioaccumulation of persistent pollutants. In this study the bioaccumulation of various legacy organochlorine pesticides (OCPs)-including dichlorodiphenyltrichloroethane (DDT), currently used for malaria vector control (MVC)-was assessed along with a set of biomarker responses in Müller's clawed frog Xenopus muelleri collected from the lower Phongolo River floodplain in South Africa. Possible relationships between bioaccumulation and biomarkers (of exposure, oxidative stress biomarkers, and cellular energy allocation) alongside their temporal changes were investigated. The OCP concentrations showed a significant increase over time for the duration of the study. The increase correlated negatively with rainfall from the region. DDT levels were well below expected effects levels with p,p-DDE being the main contributing metabolite. The results of this study indicate OCPs actively accumulate at sub-lethal levels in aquatic frogs from the study area, while showing possible relations towards some of the biochemical stress responses measured. Most notable were negative relationships indicated between p,p-DDE and acetylcholinesterase, malondialdehyde, and carbohydrates and protein energy availability. Levels of DDT were not found to be significantly higher than other legacy pesticides in the frog tissue, although evidence of newly introduced DDT in the frog tissue was found. Further investigation about sub-lethal effects of these pesticides on anurans is required to gain better insight into their full impact on animal livelihood.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados/toxicidade , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Xenopus/fisiologia , Animais , Biomarcadores/metabolismo , Malária , África do Sul
4.
Environ Sci Pollut Res Int ; 24(30): 23763-23770, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28865000

RESUMO

Ethiopia and South Africa are among the few countries to still implement indoor residual spraying with dichloro-diphenyl-trichloroethane (DDT) for malaria vector control. In this study, we investigated the levels and ecological risks of DDT and its metabolites in liver tissues of house rat, as a sentinel animal, for providing an early warning system for public health and wildlife intervention from Ethiopia and South Africa. The results showed that ΣDDT concentration ranged from 127 to 9155 µg/kg wet weight, and the distribution order of DDT and its metabolites in the analyzed liver samples was p,p'-DDD > p,p'-DDE >> p,p'-DDT, o,p'-DDT, and o,p'-DDD. The risk assessment indicated a potential adverse impact on humans, especially for pregnant women and children, because they spend majority of their time in a DDT-sprayed house. The ecological assessment also showed a concern for birds of prey and amphibians like frogs. This study is the first report on DDT contamination in liver tissues of house rats from Ethiopia and South Africa, and henceforth, the data will serve as a reference data for future studies.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , DDT/análise , Biomarcadores Ambientais , Exposição Ambiental/análise , Inseticidas/análise , Fígado/química , Animais , Etiópia , Humanos , Malária/prevenção & controle , Ratos , Medição de Risco , África do Sul
5.
J Vet Med Sci ; 79(4): 807-814, 2017 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-28302954

RESUMO

Seabirds are marine top predators and accumulate high levels of metals and metalloids in their tissues. Contamination by metals in the highly productive offshore region has become a matter of public concern. It is home to 80% of the seabird population in the U.S.A., 95% of northern fur seals (Callorhinus ursinus), and major populations of Steller sea lions (Eumetopias jubatus), walruses (Odobenus rosmarus) and whales. Here, the concentrations of eight heavy metals (Hg, Cd, Cr, Co, Ni, Cu, Zn and Pb) and a metalloid (As) in the liver and kidneys of the northern fulmar (Fulmarus glacialis), thick-billed murre (Uria lomvia), short-tailed shearwater (Puffinus tenuirostris), tufted puffin (Fratercula cirrhata) and horned puffin (Fratercula corniculata) collected in the Bering Sea were measured. As proxies of trophic level and habitat, nitrogen (δ15N) and carbon (δ13C) stable isotope ratios of breast muscles were also measured. Hepatic Hg concentration was high in northern fulmar, whereas Cd level was high in tufted puffin and northern fulmar. The Hg concentration and δ15N value were positively correlated across individual birds, suggesting that Hg uptake was linked to the trophic status of consumed prey. Furthermore, Hg concentration in our study was higher than those of the same species of seabirds collected in 1990.


Assuntos
Arsênico/análise , Charadriiformes , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental , Feminino , Rim/química , Fígado/química , Masculino , Oceano Pacífico
6.
Bull Environ Contam Toxicol ; 98(2): 172-177, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28035427

RESUMO

Concentrations of ten trace elements (Hg, As, Cd, Pb, Co, Cr, Cu, Ni, Se and Zn) were determined in different tissues (liver, kidney, muscle, heart and brain) of African sacred ibis (Threskiornis aethiopicus), Hamerkop (Scopus umbretta), marabou stork (Leptoptilos crumeniferus) and great white pelican (Pelecanus onocrotalus) inhabiting the Ethiopian Rift Valley region. There were differences in trace element patterns among the bird species. Significantly (p < 0.05) higher concentrations of Cd (5.53 µg/g dw ± 2.94) in kidney and Hg (0.75 µg/g ww ± 0.30) in liver were observed in the great white pelican compared to the other species, and liver concentrations of these two elements showed positive correlations with trophic level. Concentrations of toxic elements (As, Cd, Pb and Hg) in liver were below their respective toxicological thresholds, indicating that the data may provide baseline information for future studies.


Assuntos
Aves/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Oligoelementos/metabolismo , Animais , Poluentes Ambientais/análise , Etiópia , Rim/metabolismo , Fígado/metabolismo , Músculos/metabolismo , Oligoelementos/análise
7.
J Health Pollut ; 7(15): 28-39, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30524828

RESUMO

Background: Environmental contamination with heavy metals and metalloids due to industrial, smelting and mining activities have become common in large and growing cities. Kumasi is one of the most industrialized cities in Ghana and experiences metal pollution due to recent and past activities. Although metals are naturally abundant in the area, their accumulation in soils could potentially lead to adverse effects on local ecosystems. Objectives: The aims of this study were to determine the distribution, enrichment, geoaccumulation and sources of metals in Kumasi soils and to estimate the contamination factor (CF) and pollution load index (PLI) of these metals in soils. Methods: Concentrations of eight heavy metals and a metalloid were determined in 112 soil samples randomly collected from 31 sampling sites in the area. In addition, 5 soil samples were collected from a pristine site (Kwame Nkrumah University of Science and Technology Botanical Gardens) for data comparison, to determine the local background values for metal concentrations and to evaluate the extent of metal pollution in the study area. Results: Heavy metals such as zinc (Zn), lead (Pb), cadmium (Cd) and chromium (Cr) were enriched in 65, 32, 58 and 93% of the sampling sites, respectively, and geo-accumulation indexes for Cr, Zn, Cd, mercury (Hg) and Pb showed moderate to extreme contamination in 100, 97, 77, 65 and 45% of the sampling sites, respectively. Principal component and cluster analyses revealed that industrial activities including mining were the major sources of metals in Kumasi soils with high metal input in the community of Suame. Distribution maps revealed hotspots of Cd, nickel (Ni), arsenic (As), cobalt (Co), copper (Cu) and Pb in Suame. The highest CFs for Cu, Cd, Ni, As, Co and Pb highlighted anthropogenic inputs in Suame, while Hg was highest in Mbrom, Zn in Suntreso, and Cr in Aboabo. Conclusions: The PLI of metals revealed Suame as the most polluted study site, while Anomangye and Bomso were the least polluted.

8.
Sci Total Environ ; 574: 1389-1395, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27539819

RESUMO

Despite the presence of a wide variety and number of birds, there is exceedingly little data on organochlorine pesticide (OCP) residues in birds inhabiting in Africa. In the present study, concentrations of dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes, drins, cyclodienes, and hexachlorobenzene were measured in liver, kidney, heart and brain of 4 bird species from the Rift Valley region, Ethiopia. Indoor residual spraying of DDT for malaria vector control, and indiscriminate and illegal use of pesticides underline the relevance of this study. Levels of ΣOCPs ranged from 1.87 to 4586ng/g wet weight, and the scavenger bird species Leptoptilos crumeniferus had the highest level in liver. In all tissues, contamination profiles of OCPs within the species were similar, with DDTs≫other OCPs. Among the DDTs, p,p'-DDE was the most abundant compound and had significantly a higher burden in all tissues. The risk characterization demonstrated potential risks to the studied birds associated with DDE exposure. Maximum hepatic levels of p,p'-DDE exceeded the levels reported to trigger adverse effects. The detection of p,p'-DDT in all bird tissues suggests the release of fresh DDT to the environment. This is the first study to assay OCPs in different tissues of birds from the Ethiopian Rift Valley region, and henceforth the data will serve as a reference data for future studies.


Assuntos
Aves , Monitoramento Ambiental , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Animais , Etiópia , Fígado/química , Mosquitos Vetores
9.
Environ Sci Pollut Res Int ; 22(13): 9658-67, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25616380

RESUMO

Airborne particulate samples were collected on quartz filters to determine the concentrations, sources and health risks of polycyclic aromatic hydrocarbons (PAHs) in air in Kumasi, Ghana. A total of 32 air samples were collected in Kwame Nkrumah University of Science and Technology (KNUST) campus (pristine site) and city centre (CC). Samples were extracted with 1:2 v/v acetone/hexane mixture prior to GC-MS analyses. The sum of concentrations of 17 PAHs in air ranged from 0.51 to 16 (KNUST) and 19-38 ng/m(3) (CC). The concentration of benzo[a]pyrene, BaP, ranged from below detection limit to 0.08 ng/m(3) (KNUST) and 1.6 to 5.6 ng/m(3) (CC). Chemical mass balance model showed that PAHs in air in Kumasi were mainly from fuel combustion. The total BaP equivalent concentration (BaPeq) in CC was 18 times higher compared to KNUST; based on the European Legislation and Swedish and UK Standards for BaP in air, CC could be classified as highly polluted. Estimated carcinogenicity of PAHs in terms of BaPeq indicated that BaP was the principal PAH contributor in CC (70%). Health risk to adults and children associated with PAH inhalation was assessed by taking into account the lifetime average daily dose and corresponding incremental lifetime cancer risk (ILCR). The ILCR was within the acceptable range (10(-6) to 10(-4)), indicating low health risk to residents.


Assuntos
Poluentes Atmosféricos/análise , Exposição Ambiental/estatística & dados numéricos , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Adulto , Benzo(a)pireno/análise , Criança , Cidades/estatística & dados numéricos , Cromatografia Gasosa-Espectrometria de Massas , Gana , Humanos , Risco , Medição de Risco
10.
Ecotoxicol Environ Saf ; 111: 160-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25450929

RESUMO

Heavy metal and metalloid contamination in food resulting from mining is of major concern due to the potential risk involved. Food consumption is the most likely route of human exposure to metals. This study was therefore to assess metals in different organs and different animal species near gold mines used for human consumption (free-range chicken, goat and sheep) in Tarkwa, Ghana, and to estimate the daily intake and health risk. The concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, and Pb were measured with an inductively coupled plasma-mass spectrometer and Hg analysis was done using the mercury analyzer. Principal component analysis of the results showed a clear separation between chicken, grouped on one side, and the ruminants clustered on another side in both offal and muscle. Interestingly, As, Cd, Hg, Mn and Pb made one cluster in the offal of chicken. Chicken muscle also showed similar distribution with As, Hg and Pb clustered together. The daily intake of metals (µg/kg body weight/day) were in the following ranges; As [0.002 (kidneys of goat and sheep)-0.19 (chicken gizzard)], Cd [0.003 (chicken muscle)-0.55 (chicken liver)], Hg [0.002 (goat muscle)-0.29 (chicken liver)], Pb [0.01 (muscles and kidneys of goat and sheep)-0.96 (chicken gizzard)] and Mn [0.13 (goat kidney)-8.92 (sheep liver)]. From the results, daily intakes of As, Cd, Hg, Pb and Mn in these food animals were low compared to the provisional tolerable daily intake guidelines. The THQs although less than one, indicated that contributions of chicken gizzard and liver to toxic metal exposure in adults and especially children could be significant.


Assuntos
Contaminação de Alimentos/análise , Análise de Perigos e Pontos Críticos de Controle , Carne/análise , Metaloides/toxicidade , Metais/toxicidade , Mineração , Adulto , Animais , Galinhas , Criança , Gana , Cabras , Ouro , Análise de Perigos e Pontos Críticos de Controle/métodos , Saúde , Intoxicação por Metais Pesados , Humanos , Mercúrio/análise , Mercúrio/toxicidade , Metaloides/análise , Metais/análise , Nível de Efeito Adverso não Observado , Envenenamento/etiologia , Risco , Medição de Risco , Ovinos
11.
Jpn J Vet Res ; 62(3): 143-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25282956

RESUMO

Teuri Island, Hokkaido in Japan is an important place for seabirds breeding. We measured the concentrations of heavy metals (Hg, Cd, Cr, Co, Ni, Cu, Zn, and Pb) and a metalloid (As) in rhinoceros auklet (Cerorhinca monocerata) (n = 7), thick-billed murre (Uria lomvia) (n = 2), spectacled guillemot (Cepphus carbo) (n = 6), slaty-backed gull (Larus schistisagus) (n = 15), jungle crow (Corvus macrorhynchos) (n = 3), Japanese anchovy (Engraulis japonica) (n = 6) and Atka mackerel (Pleurogrammus azonus) (n = 2). Spectacled guillemot had high As concentrations, with its source being their feeding habitat. Concentration of Hg in kidney of jungle crow was higher than other seabird species at Teuri.


Assuntos
Aves/metabolismo , Poluentes Ambientais/metabolismo , Metaloides/metabolismo , Metais/metabolismo , Animais , Monitoramento Ambiental , Poluentes Ambientais/química , Japão , Metaloides/química , Metais/química
12.
Sci Total Environ ; 496: 471-478, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25108249

RESUMO

As a developing country, the economic and population growth rates in Ghana over the past few years have seen a tremendous increase. The growing rate of industrialization is gradually leading to contamination and deterioration of the environment and pollution is likely to reach disturbing levels. Surface soil samples were collected randomly from 36 communities in the Kumasi Metropolis, Ghana, to determine the concentrations, distribution, sources and toxic potential of emission of polycyclic aromatic hydrocarbons (PAHs) since no such comprehensive study had been conducted. The mean concentration of total PAHs in the surface soils in each community ranged from 14.78 at Ahinsan to 2084 ng/g dry weight at Adum with an average of 442.5 ± 527.2 ng/g dry weight. Diagnostic ratios and chemical mass balance models of the results showed that PAHs in surface soil samples from the study area were mainly from fuel combustion. Carcinogenic potency of PAH load from the city centre was approximately 150 times higher as compared to a pristine site, Kwame Nkrumah University of Science and Technology's Botanical Garden. BaP, a human carcinogen, contributed 70% of the total PAHs toxicity level from the city centre of Kumasi.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Solo/química , Poluição Ambiental/estatística & dados numéricos , Gana
13.
Environ Pollut ; 192: 121-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24907858

RESUMO

Organochlorine pesticides (OCPs) and stable isotopes were measured in muscle from 4 bird and 5 fish species from the Ethiopian Rift Valley region where DDT is used for malaria control and vast agricultural activities are carried out. We investigated the bioaccumulation of OCPs such as DDTs, HCHs, chlordanes, and heptachlors between the species, and examined the potential risk posed by these compounds for bird species. Significant differences in contaminant profiles and levels were observed within the species. Levels of total OCPs ranged from 3.7 to 148.7 µg/g lipid in bird and 0.04 to 10.9 µg/g lipid in fish species. DDTs were the predominant contaminant, and a positive relationship between δ(15)N and ΣDDT concentrations was found. The main DDT metabolite, p,p'-DDE was the most abundant and significantly greater concentrations in bird species (up to 138.5 µg/g lipid), which could have deleterious effects on survival and/or reproduction of birds.


Assuntos
Aves/metabolismo , Monitoramento Ambiental , Peixes/metabolismo , Hidrocarbonetos Clorados/metabolismo , Praguicidas/metabolismo , Poluentes Químicos da Água/metabolismo , Agricultura , Animais , Diclorodifenil Dicloroetileno/metabolismo , Etiópia , Cadeia Alimentar , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Rios , Poluentes Químicos da Água/análise
14.
Environ Sci Pollut Res Int ; 20(12): 8663-71, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23709296

RESUMO

Dichlorodiphenyltrichloroethanes (DDTs) and heavy metals are ubiquitous contaminants with high bioaccumulation and persistence in the environment, which can have adverse effects on humans and animals. Although applications of DDTs have been banned in many countries, developing countries like Ethiopia are still using these for agricultural and medicinal purposes. In addition, heavy metals are naturally present in the aquatic environment and distributed globally. In this study, the occurrence, distribution, and ecological risk of DDTs and heavy metals in surface sediments from one of the Ethiopian rift valley lakes were studied. Twenty-five surface sediment samples from Lake Awassa, Ethiopia were collected and analyzed for DDTs and heavy metals. Results showed that concentrations of total DDTs ranged from 3.64 to 40.2 ng/g dry weight. High levels of DDTs were observed in the vicinity of inflow river side and coastal areas with agricultural activities. The heavy metals content were followed the order Zn>Ni>Pb>Cu>Cr>Co>As>Cd>Hg. Correlation analysis and principal components analysis demonstrated that heavy metals were originated from both natural and anthropogenic inputs. The levels of DDE and DDD in surface sediments exceeded the sediment quality guideline values, indicating that adverse effects may occur to the lake. A method based on toxic-response factor for heavy metals revealed that the calculated potential ecological risk indices showed low ecological risk for the water body.


Assuntos
DDT/análise , Monitoramento Ambiental , Sedimentos Geológicos/química , Lagos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , Países em Desenvolvimento , Ecologia , Etiópia , Humanos , Medição de Risco
15.
Chemosphere ; 91(6): 857-63, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23422170

RESUMO

The levels and bioaccumulation of organochlorine pesticides (OCPs) and heavy metals were studied in muscle and liver of three fish species, with two trophic levels, from Lake Awassa, Ethiopia. DDTs were the predominant organic pollutant in all species with a maximum level of 73.28 ng g(-1) wet weight (ww). p,p'-DDE was the predominate congener and showed a significant (p<0.001) relationship with δ(15)N, which indicates that DDTs could biomagnified in the food web of the lake. Generally, high levels of heavy metals (Cd, Co, Cr, Cu, Ni, Pb, Zn and Hg) were found in liver samples as compared to muscles. The levels of Cd, Co, Cu, Ni, and Pb in liver samples showed negative correlation with δ(15)N. They were found markedly higher in the lower trophic level fish species (p<0.05) that indicates biodilution whereas; Zn level showed positive correlation with δ(15)N.


Assuntos
Monitoramento Ambiental/métodos , Peixes , Hidrocarbonetos Clorados/análise , Lagos/química , Metais Pesados/análise , Praguicidas/análise , Poluentes Químicos da Água/análise , Animais , Ingestão de Alimentos , Etiópia , Humanos , Isótopos , Medição de Risco
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