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1.
Environ Res ; 233: 116508, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37392824

RESUMO

Even relatively low levels of metals exposure may impact health, particularly among vulnerable populations such as infants and young children. However, little is known about the interplay between simultaneous metal exposures, common in real-life scenarios, and their association with specific dietary patterns. In this study, we have evaluated the association between adherence to Mediterranean diet (MD) and urinary metal concentrations individually and as an exposure mixture in 713 children aged 4-5-years from the INMA cohort study. We used a validated food frequency questionnaire to calculate two MD indexes scores: aMED and rMED. These indexes gather information on various food groups within the MD and score differently. To measure urinary concentrations of cobalt, copper, zinc, molybdenum, selenium, lead, and cadmium as exposure biomarkers, we used inductively coupled plasma mass spectrometry (ICP-MS), coupled with an ion chromatography (IC) equipment for arsenic speciation analysis. We applied linear regression and quantile g-computation, adjusted for confounders, to analyse the association between MD adherence and exposure to the metal mixture. High adherence to MD such as the quintile (Q) 5 MD was associated with higher urinary arsenobetaine (AsB) levels than Q1, with ß values of 0.55 (confidence interval - CI 95% 0.01; 1.09) for aMED and 0.73 (CI 95% 0.13; 1.33) for rMED. Consumption of fish was associated with increased urinary AsB but reduced inorganic arsenic concentrations. In contrast, the aMED vegetables consumption increased urinary inorganic arsenic content. A moderate level of adherence to MD (Q2 and Q3) was associated with lower copper urinary concentrations than Q1, with ß values of -0.42 (CI 95% -0.72; -0.11) for Q2 and -0.33 (CI 95% -0.63; -0.02) for Q3, but only with aMED. Our study, conducted in Spain, revealed that adhering to the MD reduces exposure to certain metals while increasing exposure to others. Specifically, we observed increase in exposure to non-toxic AsB, highlighting the significance of consuming fish/seafood. However, it is crucial to emphasize the necessity for additional efforts in reducing early-life exposure to toxic metals, even when adhering to certain food components of the MD.


Assuntos
Arsênio , Dieta Mediterrânea , Animais , Arsênio/urina , Cobre , Estudos de Coortes , Espanha , Metais
2.
Food Chem ; 338: 127842, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32822902

RESUMO

Cadmium, inorganic arsenic and, potentially, dimethyl arsenic acid are carcinogens widely elevated in rice. Here it was identified that the food-safe and common cadmium chelator citric acid efficiently removed cadmium from intact grain via pre-soaking procedure, while also reducing arsenic species. A twostep pre-soaking stage was developed whereby rice was first incubated, at ambient temperature, in 1 M citric acid for 12 h, and then in 1 M calcium carbonate for another 12 h, the latter step to neutralize pH, followed by cooking. When 10 different individual types of rice were processed in such a way this resulted in removal rates of 79% for cadmium, 81% for inorganic arsenic and a 66% for DMA. The technology is particularly suitable for bulk food processing and could be deployed in the most cadmium and arsenic impacted regions where rice is a staple.


Assuntos
Arsenicais/química , Ácido Cacodílico/química , Cádmio/química , Contaminação de Alimentos/análise , Oryza/química , Arsenicais/análise , Ácido Cacodílico/análise , Cádmio/análise , Carbonato de Cálcio/química , Ácido Cítrico/química , Culinária/métodos , Concentração de Íons de Hidrogênio , Espectrometria de Massas/métodos , Oryza/metabolismo
3.
J Dairy Sci ; 103(8): 6930-6939, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32475661

RESUMO

Diets worldwide are deficient in iodine, leading to a range of undesirable health effects at the population level. Dairy products are a primary source of iodine in diets for those populations in which iodized salt is not systematically used or available. However, the flows of iodine through dairy agroecosystems are not well understood. The aim of this research was to investigate iodine flows though the dairy agroecosystem, including the influence of atmospheric depositional inputs, environmental variables, season, husbandry, and diet. Three farm-based sampling campaigns were carried out in this investigation, with milk, soil, silage, grass, and feed iodine determined by inductively coupled plasma mass spectroscopy, and nonparametric statistical analysis tests were conducted on data sets obtained. Natural iodine inputs into the environment are dominated by atmospheric deposition, which mainly from sea spray, and thus the location of farms relative to the coast and prevailing wind direction. Herbage and silage produced from grass-based systems strongly correlated with soil iodine, yet there was a strong disconnect between soil, forage, and feed and the milk that results. This was due to the levels of iodine in supplemental feeds being approximately 10-fold higher than those in forage-derived feeds. The practice of feed supplementation, accentuated by summer housing of cows, led to elevated milk iodine.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Dieta/veterinária , Iodo/administração & dosagem , Leite/química , Silagem/análise , Animais , Feminino , Iodo/química , Lactação , Poaceae , Estações do Ano , Solo
4.
Environ Pollut ; 194: 181-187, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25145278

RESUMO

Patterns of arsenic excretion were followed in a cohort (n = 6) eating a defined rice diet, 300 g per day d.wt. where arsenic speciation was characterized in cooked rice, following a period of abstinence from rice, and other high arsenic containing foods. A control group who did not consume rice were also monitored. The rice consumed in the study contained inorganic arsenic and dimethylarsinic acid (DMA) at a ratio of 1:1, yet the urine speciation was dominated by DMA (90%). At steady state (rice consumption/urinary excretion) ∼40% of rice derived arsenic was excreted via urine. By monitoring of each urine pass throughout the day it was observed that there was considerable variation (up to 13-fold) for an individual's total arsenic urine content, and that there was a time dependent variation in urinary total arsenic content. This calls into question the robustness of routinely used first pass/spot check urine sampling for arsenic analysis.


Assuntos
Arsênio/urina , Dieta/estatística & dados numéricos , Poluentes Ambientais/urina , Contaminação de Alimentos/análise , Oryza/química , Arsênio/análise , Ácido Cacodílico/urina , Poluentes Ambientais/análise , Alimentos , Humanos , Masculino
5.
Environ Pollut ; 181: 38-43, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23810819

RESUMO

Rice is comparatively efficient at assimilating inorganic arsenic (Asi), a class-one, non-threshold carcinogen, into its grain, being the dominant source of this element to mankind. Here it was investigated how the total arsenic (Ast) and Asi content of Italian rice grain sourced from market outlets varied by geographical origin and type. Total Cr, Cd Se, Mg, K, Zn, Ni were also quantified. Ast concentration on a variety basis ranged from means of 0.18 mg kg(-1) to 0.28 mg kg(-1), and from 0.11 mg kg(-1) to 0.28 mg kg(-1) by production region. For Asi concentration, means ranged from 0.08 mg kg(-1) to 0.11 mg kg(-1) by variety and 0.10 mg kg(-1) to 0.06 mg kg(-1) by region. There was significant geographical variation for both Ast and Asi; total Se and Ni concentration; while the total concentration of Zn, Cr, Ni and K were strongly influenced by the type of rice.


Assuntos
Arsênio/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Oryza/química , Contaminação de Alimentos/estatística & dados numéricos , Geografia
6.
Chem Commun (Camb) ; (28): 4257-9, 2009 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-19585039

RESUMO

The molecular structure of a variety of novel mercury-phytochelatin complexes was evidenced in rice plants exposed to inorganic mercury (Hg2+) using RP-HPLC with simultaneous detection via ICP-MS and ES-MS.


Assuntos
Espectrometria de Massas/métodos , Mercúrio/química , Peptídeos/química , Plantas/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular
7.
New Phytol ; 184(1): 193-201, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19549132

RESUMO

Arsenic (As) contamination of rice grains and the generally low concentration of micronutrients in rice have been recognized as a major concern for human health. Here, we investigated the speciation and localization of As and the distribution of (micro)nutrients in rice grains because these are key factors controlling bioavailability of nutrients and contaminants. Bulk total and speciation analyses using high-pressure liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry (ICP-MS) and X-ray absorption near-edge spectroscopy (XANES) was complemented by spatially resolved microspectroscopic techniques (micro-XANES, micro-X-ray fluorescence (micro-XRF) and particle induced X-ray emission (PIXE)) to investigate both speciation and distribution of As and localization of nutrients in situ. The distribution of As and micronutrients varied between the various parts of the grains (husk, bran and endosperm) and was characterized by element-specific distribution patterns. The speciation of As in bran and endosperm was dominated by As(III)-thiol complexes. The results indicate that the translocation from the maternal to filial tissues may be a bottleneck for As accumulation in the grain. Strong similarities between the distribution of iron (Fe), manganese (Mn) and phosphorus (P) and between zinc (Zn) and sulphur (S) may be indicative of complexation mechanisms in rice grains.


Assuntos
Arsênio/metabolismo , Minerais/metabolismo , Oryza/metabolismo , Sementes/metabolismo , Transporte Biológico , Cromatografia Líquida de Alta Pressão , Fluorescência , Pós , Padrões de Referência , Espectrofotometria Atômica , Análise Espectral , Raios X
8.
New Phytol ; 181(4): 777-794, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19207683

RESUMO

Arsenic (As) is an element that is nonessential for and toxic to plants. Arsenic contamination in the environment occurs in many regions, and, depending on environmental factors, its accumulation in food crops may pose a health risk to humans.Recent progress in understanding the mechanisms of As uptake and metabolism in plants is reviewed here. Arsenate is taken up by phosphate transporters. A number of the aquaporin nodulin26-like intrinsic proteins (NIPs) are able to transport arsenite,the predominant form of As in reducing environments. In rice (Oryza sativa), arsenite uptake shares the highly efficient silicon (Si) pathway of entry to root cells and efflux towards the xylem. In root cells arsenate is rapidly reduced to arsenite, which is effluxed to the external medium, complexed by thiol peptides or translocated to shoots. One type of arsenate reductase has been identified, but its in planta functions remain to be investigated. Some fern species in the Pteridaceae family are able to hyperaccumulate As in above-ground tissues. Hyperaccumulation appears to involve enhanced arsenate uptake, decreased arsenite-thiol complexation and arsenite efflux to the external medium, greatly enhanced xylem translocation of arsenite, and vacuolar sequestration of arsenite in fronds. Current knowledge gaps and future research directions are also identified.


Assuntos
Arsênio/metabolismo , Plantas/metabolismo , Aquaporinas/metabolismo , Aquaporinas/fisiologia , Arsênio/química , Transporte Biológico , Floema/metabolismo , Fosfatos/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Plantas/genética , Plantas/microbiologia , Rizosfera
9.
Environ Int ; 35(3): 480-4, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18793800

RESUMO

Arsenic (As) is mobilized from delta and floodplain aquifer sediments throughout S.E. Asia via reductive dissolution of As bound to iron (Fe) oxyhydroxides. The reductive driving force is organic carbon, but its source and constitution is uncertain. Here batch incubation experiments were conducted to investigate the role of organic matter (OM) carbon:nitrogen (C:N) ratio on the mobilization of arsenic, Fe and N from As dosed, Fe oxyhydroxide coated sands. As mobilization into pore waters from the sand was strongly regulated by the C:N ratio of the OM, and also the concentration of OM present. The lower the C:N, the more As released. Fe and ammonium release were similarly dependent on the quality and quantity of OM, but Fe mobilization was more rapid and ammonium release slower than As suggesting that the mobilization of these 3 moieties although interdependent, were not directly linked. It was concluded that low C:N ratios for OM responsible for reducing aquifers were As in groundwater is observed were likely.


Assuntos
Arsênio/análise , Carbono/análise , Compostos Férricos/análise , Sedimentos Geológicos/química , Nitrogênio/análise , Sudeste Asiático , Ferro/análise , Compostos Orgânicos/análise , Compostos de Amônio Quaternário/análise
10.
Environ Pollut ; 157(3): 946-54, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19062145

RESUMO

Arsenic is known to accumulate with iron plaque on macrophyte roots. Three to four years after the Aznalcóllar mine spill (Spain), residual arsenic contamination left in seasonal wetland habitats has been identified in this form by scanning electron microscopy. Total digestion has determined arsenic concentrations in thoroughly washed 'root+plaque' material in excess of 1000 mg kg(-1), and further analysis using X-ray absorption spectroscopy suggests arsenic exists as both arsenate and arsenite. Certain herbivorous species feed on rhizomes and bulbs of macrophytes in a wide range of global environments, and the ecotoxicological impact of consuming arsenic rich iron plaque associated with such food items remains to be quantified. Here, greylag geese which feed on Scirpus maritimus rhizome and bulb material in areas affected by the Aznalcóllar spill are shown to have elevated levels of arsenic in their feces, which may originate from arsenic rich iron plaque.


Assuntos
Arsênio/análise , Ferro/análise , Raízes de Plantas/química , Poluentes do Solo/análise , Ecotoxicologia/métodos , Sedimentos Geológicos/química , Risco , Espanha
11.
Environ Sci Technol ; 42(15): 5574-9, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18754478

RESUMO

Arsenic (As) exposure from consumption of rice can be substantial, particularly for the population on a subsistence rice diet in South Asia. Paddy rice has a much enhanced As accumulation compared with other cereal crops, and practical measures are urgently needed to decrease As transfer from soil to grain. We investigated the dynamics of As speciation in the soil solution under both flooded and aerobic conditions and compared As accumulation in rice shoot and grain in a greenhouse experiment. Flooding of soil led to a rapid mobilization of As, mainly as arsenite, in the soil solution. Arsenic concentrations in the soil solution were 7-16 and 4-13 times higher under the flooded than under the aerobic conditions in the control without As addition and in the +As treatments (10 mg As kg(-1) as arsenite or arsenate), respectively. Arsenate was the main As species in the aerobic soil. Arsenic accumulation in rice shoots and grain was markedly increased under flooded conditions; grain As concentrations were 10-15-fold higher in flooded than in aerobically grown rice. With increasing total As concentrations in grain, the proportion of inorganic As decreased, while that of dimethylarsinic acid (DMA) increased. The concentration of inorganic As was 2.6-2.9 fold higher in the grain from the flooded treatment than in that from the aerobic treatment. The results demonstrate that a greatly increased bioavailability of As under the flooded conditions is the main reason for an enhanced As accumulation by flooded rice, and growing rice aerobically can dramatically decrease the As transfer from soil to grain.


Assuntos
Arsênio/farmacocinética , Monitoramento Ambiental , Inundações , Oryza/metabolismo , Brotos de Planta/metabolismo , Poluentes do Solo/farmacocinética , Poluentes Químicos da Água/farmacocinética , Aerobiose , Arseniatos/farmacocinética , Arseniatos/toxicidade , Arsênio/toxicidade , Arsenitos/farmacocinética , Arsenitos/toxicidade , Ásia , Disponibilidade Biológica , Oryza/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Poluentes do Solo/toxicidade , Fatores de Tempo , Poluentes Químicos da Água/toxicidade
12.
Environ Sci Technol ; 42(13): 5008-13, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18678041

RESUMO

Two approaches were undertaken to characterize the arsenic (As) content of Chinese rice. First, a national market basket survey (n = 240) was conducted in provincial capitals, sourcing grain from China's premier rice production areas. Second, to reflect rural diets, paddy rice (n = 195) directly from farmers fields were collected from three regions in Hunan, a key rice producing province located in southern China. Two of the sites were within mining and smeltery districts, and the third was devoid of large-scale metal processing industries. Arsenic levels were determined in all the samples while a subset (n = 33) were characterized for As species, using a new simple and rapid extraction method suitable for use with Hamilton PRP-X100 anion exchange columns and HPLC-ICP-MS. The vast majority (85%) of the market rice grains possessed total As levels < 150 ng g(-1). The rice collected from mine-impacted regions, however, were found to be highly enriched in As, reaching concentrations of up to 624 ng g(-1). Inorganic As (As(i)) was the predominant species detected in all of the speciated grain, with As(i) levels in some samples exceeding 300 ng g(-1). The As(i) concentration in polished and unpolished Chinese rice was successfully predicted from total As levels. The mean baseline concentrations for As(i) in Chinese market rice based on this survey were estimated to be 96 ng g(-1) while levels in mine-impacted areas were higher with ca. 50% of the rice in one region predicted to fail the national standard.


Assuntos
Arsênio/análise , Contaminação de Alimentos/análise , Mineração , Oryza/química , China , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Espectrometria de Massas
13.
Environ Sci Technol ; 41(7): 2178-83, 2007 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-17438760

RESUMO

We report the largest market basket survey of arsenic (As) in U.S. rice to date. Our findings show differences in transitional-metal levels between polished and unpolished rice and geographical variation in As and selenium (Se) between rice processed in California and the South Central U.S. The mean and median As grain levels for the South Central U.S. were 0.30 and 0.27 mimcrog As g(-1), respectively, for 107 samples. Levels for California were 41% lower than the South Central U.S., with a mean of 0.17 microg As g(-1) and a median of 0.16 microg As g(-1) for 27 samples. The mean and median Se grain levels for the South Central U.S. were 0.19 microg Se g(-1). Californian rice levels were lower, averaging only 0.08 and 0.06 microg Se g(-1) for mean and median values, respectively. The difference between the two regions was found to be significant for As and Se (General Linear Model (GLM): As p < 0.001; Se p < 0.001). No statistically significant differences were observed in As or Se levels between polished and unpolished rice (GLM: As p= 0.213; Se p= 0.113). No significant differences in grain levels of manganese (Mn), cobalt (Co), copper (Cu), or zinc (Zn) were observed between California and the South Central U.S. Modeling arsenic intake for the U.S. population based on this survey shows that for certain groups (namely Hispanics, Asians, sufferers of Celiac disease, and infants) dietary exposure to inorganic As from elevated levels in rice potentially exceeds the maximum intake of As from drinking water (based on consumption of 1 L of 0.01 mg L(-1) In. As) and Californian state exposure limits. Further studies on the transformation of As in soil, grain As bioavailability in the human gastrointestinal tract, and grain elemental speciation trends are critical.


Assuntos
Arsênio/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Modelos Teóricos , Oryza/química , Geografia , Humanos , Modelos Lineares , Espectrometria de Massas , Análise de Componente Principal , Medição de Risco , Estados Unidos
14.
Environ Int ; 33(6): 759-65, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17433834

RESUMO

Gyps vulture populations across the Indian subcontinent are declining rapidly and evidence indicates that veterinary use of the non-steroidal anti-inflammatory drug (NSAID) diclofenac is the major cause. Exposure of vultures to diclofenac is likely to arise from the consumption of livestock carcasses that have been treated shortly before death, however, detailed information regarding the prevalence and residual levels of diclofenac in carcasses available to vultures in India remains unreported. Here, we present data on diclofenac residues in 1848 liver samples taken from carcasses of dead livestock sampled at 67 sites in 12 states within India, between May 2004 and July 2005. Diclofenac residues were detected in carcasses in all states except Orisa, where only one site was sampled. The overall prevalence of detectable diclofenac (>10 microg kg(-1)) across all states was 10.1% and varied significantly among states, with up to 22.3% prevalence determined in Bihar. The geometric mean concentration of diclofenac found in samples in which the drug was detected was 352 microg kg(-1). The prevalence of carcasses containing diclofenac is similar to that previously proposed to be required to have caused the observed Gyps vulture declines in India. On the 11th of May 2006, the Drug Controller General (India) ordered the withdrawal of all licenses granted for the manufacture of diclofenac for veterinary use within India. However, if Gyps vultures are to be protected, potentially substantial existing stocks now need to be quickly and effectively removed from the Indian veterinary market.


Assuntos
Animais Domésticos/metabolismo , Anti-Inflamatórios não Esteroides/metabolismo , Diclofenaco/metabolismo , Falconiformes/metabolismo , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Bovinos , Diclofenaco/toxicidade , Comportamento Alimentar/efeitos dos fármacos , Feminino , Índia , Masculino
15.
Sci Total Environ ; 376(1-3): 116-27, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17307237

RESUMO

Since 1989, a red kite Milvus milvus reintroduction programme has been underway in the United Kingdom, with 4-6 week old nestlings brought into captivity and held for 6-8 weeks before reintroduction. As scavengers, red kites may consume unretrieved game, and ingest shot or lead (Pb) fragments in their prey's flesh. We evaluated exposure to Pb in captive and wild red kites by taking blood samples from 125 captive young red kites prior to release, through analysing 264 pellets (regurgitated by wild birds) collected from under a roost site, and analysing Pb concentrations in livers and/or bones of 87 red kites found dead between 1995 and 2003. Lead isotope analyses of livers were also conducted in an effort to identify Pb exposure routes. Forty-six (36.8%) kites sampled prior to release had elevated blood Pb concentrations (201-3340 microg l(-1)). The source of this Pb was probably small fragments of lead ammunition in the carcasses of birds or mammals either fed to the nestlings by their parents or, more likely, subsequently whilst in captivity. Once released, kites were also exposed to lead shot in their food, and a minimum of 1.5-2.3% of regurgitated pellets contained Pb gunshot. Seven of 44 red kites found dead or that were captured sick and died within a few days had elevated (>6 mg kg(-1) dry weight [d.w.]) liver Pb concentrations, and six of these (14%) had concentrations of >15 mg kg(-1) d.w., compatible with fatal Pb poisoning. Post-mortem analyses indicated that two of these birds had died of other causes (poisoning by rodenticide and a banned agricultural pesticide); the remaining four (9%) probably died of Pb poisoning. Bone samples from 86 red kites showed a skewed distribution of Pb concentration, and 18 samples (21%) had Pb concentrations >20 mg kg(-1) d.w., indicating elevated exposure to Pb at some stage in the birds' life. Lead isotopic signatures (Pb (208/206); Pb (206/207)) in liver samples of the majority of kites were compatible with those found in lead shot extracted from regurgitated pellets. Lead isotope ratios found in the livers of kites with very low Pb concentrations were distinct from UK petrol Pb isotopic signatures, indicating that birds were exposed to little residual petrol Pb. We conclude that the primary source of Pb to which red kites are exposed is lead ammunition (shotgun pellets or rifle bullets), or fragments thereof, in their food sources; in some cases exposure appears sufficient to be fatal. We make recommendations to reduce Pb poisoning in both captive and wild red kites and other scavenging species.


Assuntos
Poluentes Ambientais/análise , Falconiformes/metabolismo , Chumbo/análise , Animais , Osso e Ossos/metabolismo , Dieta , Poluentes Ambientais/metabolismo , Falconiformes/sangue , Armas de Fogo , Chumbo/metabolismo , Fígado/metabolismo , Coelhos
16.
Environ Pollut ; 147(1): 60-5, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17069941

RESUMO

Gyps vultures across India are declining rapidly and the NSAID diclofenac has been shown to be the major cause. Vultures scavenge livestock carcasses that have been treated with diclofenac within the days preceding death. We present data on diclofenac disposition in Indian cow and goat, and field data on the prevalence of diclofenac in carcases in the environment. In the disposition experiment, animals were treated with a single intramuscular injection of diclofenac at 1000 microg kg-1 bw. In cow, diclofenac was detectable in liver, kidney and intestine up to 71 h post-treatment; in plasma, half-life was 12.2 h. In goat, tissue residues were undetectable after 26 h. Prevalence of diclofenac in liver from 36 dead livestock collected in the field was 13.9%. Data suggest that diclofenac residues in Indian cow and goat are short-lived, but diclofenac prevalence in carcasses available to vultures may still be very high.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Diclofenaco/farmacocinética , Resíduos de Drogas/análise , Falconiformes/fisiologia , Contaminação de Alimentos/análise , Carne/análise , Animais , Bovinos , Cadeia Alimentar , Cabras , Meia-Vida , Índia , Intestinos/química , Rim/química , Fígado/química , Dinâmica Populacional
17.
Environ Sci Technol ; 40(18): 5730-6, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-17007133

RESUMO

A compartmented soil-glass bead culture system was used to investigate characteristics of iron plaque and arsenic accumulation and speciation in mature rice plants with different capacities of forming iron plaque on their roots. X-ray absorption near-edge structure spectra and extended X-ray absorption fine structure were utilized to identify the mineralogical characteristics of iron plaque and arsenic sequestration in plaque on the rice roots. Iron plaque was dominated by (oxyhydr)oxides, which were composed of ferrihydrite (81-100%), with a minor amount of goethite (19%) fitted in one of the samples. Sequential extraction and XANES data showed that arsenic in iron plaque was sequestered mainly with amorphous and crystalline iron (oxyhydr)oxides, and that arsenate was the predominant species. There was significant variation in iron plaque formation between genotypes, and the distribution of arsenic in different components of mature rice plants followed the following order: iron plaque > root > straw > husk > grain for all genotypes. Arsenic accumulation in grain differed significantly among genotypes. Inorganic arsenic and dimethylarsinic acid (DMA) were the main arsenic species in rice grain for six genotypes, and there were large genotypic differences in levels of DMA and inorganic arsenic in grain.


Assuntos
Arsênio/química , Arsênio/metabolismo , Ferro/química , Ferro/metabolismo , Oryza/metabolismo , Absorciometria de Fóton/métodos , Raízes de Plantas/metabolismo , Solo/análise
18.
Environ Sci Technol ; 40(16): 4903-8, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16955884

RESUMO

Concern has been raised by Bangladeshi and international scientists about elevated levels of arsenic in Bengali food, particularly in rice grain. This is the first inclusive food market-basket survey from Bangladesh, which addresses the speciation and concentration of arsenic in rice, vegetables, pulses, and spices. Three hundred thirty aman and boro rice, 94 vegetables, and 50 pulse and spice samples were analyzed for total arsenic, using inductivity coupled plasma mass spectrometry (ICP-MS). The districts with the highest mean arsenic rice grain levels were all from southwestern Bangladesh: Faridpur (boro) 0.51 > Satkhira (boro) 0.38 > Satkhira (aman) 0.36 > Chuadanga (boro) 0.32 > Meherpur (boro) 0.29 microg As g(-1). The vast majority of food ingested arsenic in Bangladesh diets was found to be inorganic; with the predominant species detected in Bangladesh rice being arsenite (AsIII) or arsenate (AsV) with dimethyl arsinic acid (DMAV) being a minor component. Vegetables, pulses, and spices are less important to total arsenic intake than water and rice. Predicted inorganic arsenic intake from rice is modeled with the equivalent intake from drinking water for a typical Bangladesh diet. Daily consumption of rice with a total arsenic level of 0.08 microg As g(-1) would be equivalent to a drinking water arsenic level of 10 microg L(-1).


Assuntos
Arsênio/análise , Monitoramento Ambiental/métodos , Análise de Alimentos/métodos , Contaminação de Alimentos , Oryza/metabolismo , Poluentes Químicos da Água/análise , Arseniatos/análise , Bangladesh , Ácido Cacodílico/análise , Grão Comestível , Espectrometria de Massas , Água , Poluentes da Água , Abastecimento de Água
19.
Chemosphere ; 65(2): 332-42, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16620906

RESUMO

Burning seaweed to produce kelp, valued for its high potash and soda content, was formerly a significant industry in remote coastal areas of Scotland and elsewhere. Given the high concentrations of arsenic in seaweeds, up to 100 mg kg(-1), this study investigates the possibility that the kelp industry caused arsenic contamination of these pristine environments. A series of laboratory-scale seaweed burning experiments was conducted, and analysis of the products using HPLC ICP-MS shows that at least 40% of the arsenic originally in the seaweed could have been released into the fumes. The hypothesis that the burning process transforms arsenic from low toxicity arsenosugars in the original seaweeds (Fucus vesiculosus and Laminaria digitata) to highly toxic inorganic forms, predominantly arsenate, is consistent with As speciation analysis results. A field study conducted on Westray, Orkney, once a major centre for kelp production, shows that elevated arsenic levels (10.7+/-3.0 mg kg(-1), compared to background levels of 1.7+/-0.2 mg kg(-1)) persist in soils in the immediate vicinity of the kelp burning pits. A model combining results from the burning experiments with data from historical records demonstrates the potential for arsenic deposition of 47 g ha(-1) year(-1) on land adjacent to the main kelp burning location on Westray, and for arsenic concentrations exceeding current UK soil guideline values during the 50 year period of peak kelp production.


Assuntos
Arsênio/metabolismo , Monitoramento Ambiental , Alga Marinha/química , Poluentes do Solo/metabolismo , Poluentes da Água/metabolismo , Animais , Arsênio/análise , Arsênio/toxicidade , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Escócia , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Fatores de Tempo , Poluentes da Água/análise , Poluentes da Água/toxicidade
20.
Environ Res ; 100(3): 349-61, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16165123

RESUMO

In April 1998, a holding lagoon containing pyrite ore processing waste, failed and released 5-6 million m3 of highly polluting sludge and acidic water. Over 2650 ha of the internationally important Doñana Natural Park became contaminated, along with < 100 ha of the more pristine Doñana National Park. In order to assess the affect of the spill on waterfowl from Doñana, bone and liver samples from 124 individuals have been analysed for As, Pb, Cu, Zn and Se. Five species have been studied, from the Rallidae (rails), Anatini (dabbling ducks) and Aythyini (pochards) families. Geometric mean bone concentrations 2-3 months after the spill were in the order of Zn > Cu > Pb > Se > As, while liver concentrations were in the order of Zn > Cu > Se > Pb > As. Dry weight bone concentrations ranged from n.d-1.76 mg kg(-1) As, 109.4-247.6 mg kg(-1) Zn, 0.06-1.27 mg kg(-1) Se, n.d-134.11 mg kg(-1) Pb, and 2.18-8.92 mg kg(-1) Cu. Wet weight liver concentrations ranged from n.d-0.34 mg kg(-1) As, 29.8-220.1 mg kg(-1) Zn, 0.15-0.85 mg kg(-1) Se, n.d-3.80 mg kg(-1) Pb, and 7.30-742.96 mg kg(-1) Cu. The most important factor related to the accumulation of these metals was commonly species; however, location and sex also had important effects on liver As levels, location and age affected Cu levels, while Zn and Pb were affected by age, sex and location. Birds from Natural Park areas were found to have significantly higher levels of bone Zn, Pb and Cu, and liver As and Cu than birds from National Park areas. Female birds had higher liver As, Zn and Pb than males; whilst adults appeared to have lower bone As and Zn but higher liver Pb than chicks/juveniles. Although metal concentrations were elevated in certain individuals, in the majority of birds studied, they did not reach levels widely considered to be toxic. However, it would appear that As and Cu liver levels (which may be indicative of short-medium term pollutant exposure) were elevated in waterbirds which died in the spill contaminated Natural Park, 2-3 months after the disaster.


Assuntos
Patos , Poluentes Ambientais/análise , Metais Pesados/análise , Mineração , Acidentes , Fatores Etários , Animais , Osso e Ossos/química , Monitoramento Ambiental , Poluentes Ambientais/farmacocinética , Feminino , Fígado/química , Masculino , Metais Pesados/farmacocinética , Espanha , Distribuição Tecidual
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