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1.
Ultrason Sonochem ; 56: 430-436, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31101281

RESUMO

We report a facile and ultrasound assisted sonochemical synthesis of a Tungsten disulfide nanorods decorated nitrogen-doped reduced graphene oxide based nanocomposite. The WS2 NRs/N-rGOs nanocomposite was characterized by FESEM, HRTEM, XRD, XPS and electrochemical methods and its application towards the electrochemical detection of organo-arsenic drug (coccidiostat). The WS2 NRs/N-rGOs modified SPCE was used for the electrochemical reduction of roxarsone (ROX) and it showed superior electrocatalytic performance in terms of reduction peak current and shift in overpotential when compared to those of WS2 NRs/SPCE, N-rGOs/SPCE and based SPCE. The WS2 NRs/N-rGOs modified SPCE showed an excellent sensing ability towards ROX in nitrogen saturated phosphate buffer (PB) then the other controlled modified and unmodified electrodes. The WS2 NRs/N-rGOs/SPCE displays high sensitive response towards ROX and gives wide linearity in the range of 0.1-442.6 µM ROX in neutral phosphate buffer (pH 7.0) and the sensitivity of the sensor is calculated as 14.733 µA µM-1 cm-2. The WS2 NRs/N-rGOs nanocomposite modified sensor also exhibits valuable ability of anti-interference to electroactive analytes. Furthermore, the as-prepared WS2 NRs/N-rGOs/SPCE has been applied to the determination of ROX in biological and pharmaceutical samples.


Assuntos
Antibacterianos/análise , Eletroquímica/instrumentação , Grafite/química , Limite de Detecção , Nanotubos/química , Nitrogênio/química , Roxarsona/análise , Antibacterianos/química , Catálise , Técnicas de Química Sintética , Eletrodos , Concentração de Íons de Hidrogênio , Cinética , Porosidade , Roxarsona/química
2.
Environ Pollut ; 247: 482-487, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30703681

RESUMO

Roxarsone (3-nitro-4-hydroxyphenylarsonic acid, ROX) is an arsenic-containing compound widely used as a feed additive in poultry industries. ROX excreted in chicken manure can be transformed by microbes to different arsenic species in the environment. To date, most of the studies on microbial transformation of ROX have focused on anaerobic microorganisms. Here, we isolated a pure cultured aerobic ROX-transforming bacterial strain, CZ-1, from an arsenic-contaminated paddy soil. On the basis of 16S rRNA gene sequence, strain CZ-1 was classified as a member of the genus Enterobacter. During ROX biotransformation by strain CZ-1, five metabolites including arsenate (As[V]), arsenite (As[III]), N-acetyl-4-hydroxy-m-arsanilic acid (N-AHPAA), 3-amino-4-hydroxyphenylarsonic acid (3-AHPAA) and a novel sulfur-containing arsenic species (AsC9H13N2O6S) were detected and identified based on high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS), HPLC-ICP-MS/electrospray ionization mass spectrometry (ESI-MS) and HPLC-electrospray ionization hybrid quadrupole time-of-flight mass spectrometry (ESI-qTOF-MS) analyses. N-AHPAA and 3-AHPAA were the main products, and 3-AHPAA could also be transformed to N-AHPAA. Based on the results, we propose a novel ROX biotransformation pathway by Enterobacter. sp CZ-1, in which the nitro group of ROX is first reduced to amino group (3-AHPAA) and then acetylated to N-AHPAA.


Assuntos
Arsênico/metabolismo , Biotransformação , Enterobacter/metabolismo , Roxarsona/metabolismo , Microbiologia do Solo , Animais , Arsênico/análise , Arsenicais , Galinhas/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Esterco , Espectrometria de Massas , RNA Ribossômico 16S , Roxarsona/análise , Solo
3.
Ecotoxicol Environ Saf ; 171: 493-501, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30639956

RESUMO

Roxarsone (ROX), an organoarsenic feed additive, occurs as itself and its metabolites including As(V), As(III), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) in animal manure. Animal manure improves soil biological property, whereas As compounds impact microorganisms. The integral influence of animal manure bearing ROX metabolites on soil biological quality is not clear yet. Herein, the effect of four chicken manures excreted by chickens fed with four diets containing 0, 40, 80 and 120 mg ROX kg-1, on soil biological attributes. ROX addition in chicken diets increased total As and ROX metabolites in manures, but decreased manure total N, ammonium and nitrate. The elevated ROX metabolites in manures increased soil total As, As species and total N, and increased first and then decreased soil nitrate and nitrite, but did not affect soil ammonium in manure-applied soils. The promoting role of both soil As(III) and ammonium on soil microbial biomass carbon and nitrogen, respiration and saccharase activity, were exceeded or balanced by the inhibiting effect of soil nitrate. The suppression of soil catalase activity by soil As(V) was surpassed by the enhancement caused by soil nitrate and nitrite. Soil urease, acid phosphatase and polyphenol oxidase activities were not suitable bioindicators in the four manure-amended soils. Soil DMA did not affect soil biological properties, and MMA was not detectable in all manure-amended soils. The above highlights the complexity of joint influence of soil As and N on biological attributes. Totally, when ROX is used at allowable dose in chicken diet, soil biological quality would be suppressed in manure-amended soil.


Assuntos
Esterco/análise , Roxarsona/análise , Poluentes do Solo/análise , Solo/química , Animais , Arsênico/análise , Arsenicais/análise , Biomassa , Ácido Cacodílico/análise , Carbono/análise , Galinhas , Dieta/veterinária , Nitrogênio/análise , Microbiologia do Solo
4.
Sci Total Environ ; 616-617: 1235-1241, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29074235

RESUMO

In order to evaluate the influence of roxarsone (ROX) on the livestock wastewater treatment, a lab-scale pilot employing an anoxic-oxic (A-O) process was investigated by adding different concentrations of ROX at different periods. The mass balance of arsenic (As) in the A-O system was established through the analysis of As speciation and As migration in the gas, liquid and solid phases. The results showed that around 80% of total ROX (initial concentration was 50mgROXL-1) was eliminated in the anoxic reactor (R1) in which at least about 11% of total ROX was transformed to inorganic Asv (iAsv) due to the direct breaking of the C-As bond of ROX. Inorganic AsIII (iAsIII) and arsine (AsH3) were produced in R1, while the generated iAsIII in the effluent of R1 was almost completely oxidized to iAsV in the aerobic reactor (R2). However, the concentration of ROX in the effluent of R2 was almost the same as that in the effluent of R1. After 85days operation, iAsV and residual ROX as the main forms of As were observed after the A-O process. Furthermore, the mass balance of As at steady state revealed that around 0.08%, 3.91% and 96.01% of total As was transformed into gas (biogas), solid (excess sludge) and liquid (effluent). Additionally, the 16S rRNA analysis demonstrated that the existence of ROX in livestock wastewater may play a crucial role in the diversity of bacterial community in the A-O system.


Assuntos
Roxarsona/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Animais , Gado , Roxarsona/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise
5.
Environ Pollut ; 219: 210-218, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27814537

RESUMO

Roxarsone (ROX), the primary aromatic arsenical additive (AAA) used in animal feeding operations, is of increasing concern to environmental and human health due to land application of ROX-laden animal manure. Few studies have investigated the phytotoxicity, uptake mechanisms, and speciation of AAA in crop plants. In this study, wheat seedlings were employed to address these issues under hydroponic conditions. Compared to inorganic arsenic, ROX was less toxic to wheat root elongation. Wheat roots were more sensitive to ROX stress than shoots. For the first time, metabolized inorganic arsenic was detected in plants, although ROX was the predominant detected arsenic species in wheat seedlings. ROX uptake and toxicity to roots were inhibited by humic acid at concentrations higher than 50 mg/L due to interaction with ROX. Phosphate enhanced ROX uptake, but no trends were observed for ROX uptake in the presence of glycerol at concentrations lower than 250 mM. In addition, ROX uptake was significantly decreased by silicate (Si(IV), 0.5-10 mM) and the metabolic inhibitor, 2,4-dinitrophenol (0.5-2 mM), indicating that ROX transport into wheat roots was actively mediated by Si(IV)-sensitive transporters. These findings provide important insights into the fate and speciation of AAA in soil-water-plant systems relevant to human health.


Assuntos
Arsenicais/metabolismo , Roxarsona/metabolismo , Roxarsona/toxicidade , Plântula/efeitos dos fármacos , Plântula/metabolismo , Triticum/efeitos dos fármacos , 2,4-Dinitrofenol/farmacologia , Arsênico/análise , Arsênico/metabolismo , Arsênico/toxicidade , Transporte Biológico Ativo , Poluição Ambiental/efeitos adversos , Glicerol/farmacologia , Hidroponia , Fosfatos/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Roxarsona/análise , Silicatos/farmacologia , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
6.
Chemosphere ; 155: 225-233, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27115847

RESUMO

The fate and transport of roxarsone (ROX), a widely used organoarsenic feed additive, in soil is significantly influenced by the ubiquitous presence of soil-derived dissolved organic matter (DOM). In this study, fluorescence quenching titration and two-dimensional correlation spectroscopy (2D-COS) were employed to study ROX binding to DOM. Binding mechanisms were revealed by fluorescence lifetime measurement and Fourier transform infrared spectroscopy (FTIR). Humic- and protein-like fluorophores were identified in the excitation-emission matrix and synchronous fluorescence spectra of DOM. The conditional stability constant (log KC) for ROX binding to DOM was found to be 5.06, indicating that ROX was strongly bound to DOM. The binding order of ROX to DOM fluorophores revealed by 2D-COS followed the sequence of protein-like fluorophore ≈ the longer wavelength excited humic-like (L-humic-like) fluorophore > the shorter wavelength excited humic-like (S-humic-like) fluorophore. 2D-COS resolved issues with peak overlapping and allowed further exploration of the interaction between ROX and DOM. Results of fluorescence lifetime and FTIR spectra demonstrated that ROX interacted with DOM through the hydroxyl, amide II, carboxyl, aliphatic CH, and NO2 groups, yielding stable DOM-ROX complexes. The strong interaction between ROX and DOM implies that DOM plays an important role in the environmental fate of ROX in soil.


Assuntos
Substâncias Húmicas/análise , Roxarsona/química , Poluentes do Solo/química , Solo/química , Modelos Químicos , Roxarsona/análise , Poluentes do Solo/análise , Espectrometria de Fluorescência/métodos , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Huan Jing Ke Xue ; 36(8): 3068-73, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26592042

RESUMO

The field experiment was developed for simulating the residues, transformation and degradation in soil-vegetable system of Roxarsone contained in organic fertilizer. Under the treatment, the yield of Brassica chinensis decreased in low Roxarsone concentration with a decline by 15% to 32% compared with the control group; there had an accumulating role of vegetables to arsenic, and the root was the main part; total content of arsenic in the soil was positively correlated with the dose of the applied Roxarsone; total arsenic in soil first increased and then decreased with the planting time prolonged and peaked at 12.94 mg x kg(-1), while the level of inorganic arsenic in the soil stabilized after 30 d, which accounting for 66.75% to 98.56% of the total arsenic; there existed a positively significant correlation of total arsenic content between the Brassica chinensis and the soil as well as the arsenic enrichment factor of vegetables; the degradation rate of Roxarsone in soil was slow, there was still some Roxarsone remained in soil after 45 d when added the organic fertilizer which containing Roxarsone with the dose higher than 5 000 kg x hm(-2); Roxarsone could significantly increase the number of bacteria in the soil, and low concentration showed an inhibited role in the growth of fungi and actinomyces, while high concentration of Roxarsone promoted the growth.


Assuntos
Arsênico/análise , Brassica/crescimento & desenvolvimento , Resíduos de Drogas/análise , Roxarsona/análise , Poluentes do Solo/análise , Fertilizantes , Raízes de Plantas , Solo , Verduras/crescimento & desenvolvimento
8.
J Sep Sci ; 38(17): 3063-70, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26106064

RESUMO

Response surface methodology was applied to optimize the parameters for microwave-assisted extraction of six major inorganic and organic arsenic species (As(III), As(V), dimethyl arsenic acid, monomethyl arsenic acid, p-arsanilic acid, and roxarsone) from chicken tissues, followed by detection using a high-performance liquid chromatography with inductively coupled mass spectrometry detection method, which allows the simultaneous analysis of both inorganic and organic arsenic species in the extract in a single run. Effects of extraction medium, solution pH, liquid-to-solid ratio, and the temperature and time of microwave-assisted extraction on the extraction of the targeted arsenic species were studied. The optimum microwave-assisted extraction conditions were: 100 mg of chicken tissue, extracted by 5 mL of 22% v/v methanol, 90 mmol/L (NH4 )2 HPO4 , and 0.07% v/v trifluoroacetic acid (with pH adjusted to 10.0 by ammonium hydroxide solution), ramping for 10 min to 71°C, and holding for 11 min. The method has good extraction performance for total arsenic in the spiked and nonspiked chicken tissues (104.0 ± 13.8% and 91.6 ± 7.8%, respectively), except for the ones with arsenic contents close to the quantitation limits. Limits of quantitation (S/N = 10) for As(III), As(V), dimethyl arsenic acid, monomethyl arsenic acid, p-arsanilic acid, and roxarsone in chicken tissues using this method were 0.012, 0.058, 0.039, 0.061, 0.102, and 0.240 mg/kg (dry weight), respectively.


Assuntos
Arsênico/análise , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Espectrometria de Massas/métodos , Carne/análise , Micro-Ondas , Animais , Ácido Arsanílico/análise , Arsênico/fisiologia , Arsenicais/análise , Ácido Cacodílico/análise , Galinhas , Contaminação de Alimentos , Concentração de Íons de Hidrogênio , Compostos Inorgânicos/análise , Modelos Estatísticos , Compostos Orgânicos/análise , Análise de Regressão , Roxarsona/análise , Temperatura Ambiente
9.
Environ Sci Pollut Res Int ; 22(6): 4654-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25328095

RESUMO

Roxarsone (ROX), a world widely used feed organoarsenic additive in animal production, can be excreted as itself and its metabolites in animal manure. Animal manure is commonly land applied with phosphorous (P) fertilizer to enhance the P phytoavailability in agriculture. We investigated the accumulation of As species in garland chrysanthemum (C. coronarium) plants fertilized with 1% (w/w, manure/soil) chicken manure bearing ROX and its metabolites, plus 0, 0.05, 0.1, 0.2, 0.4, and 0.8 g P2O5/kg, respectively. The results show that As(III) was the sole As compound in garland chrysanthemum shoots, and As(III) and As(V) were detectable in roots. Elevated phosphate level supplied more As(V) for garland chrysanthemum roots through competitive desorption in rhizosphere, leading to significantly enhanced accumulation of As species in plants. As(III) was the predominant As form in plants (85.0∼90.6%). Phosphate could not change the allocation of As species in plants. Hence, the traditional practice that animal manure is applied with P fertilizer may inadvertently increase the potential risk of As contamination in crop via the way ROX → animal → animal manure → soil → crop.


Assuntos
Galinhas/metabolismo , Chrysanthemum/crescimento & desenvolvimento , Fertilizantes/análise , Esterco/análise , Fósforo/análise , Roxarsona/análise , Poluentes do Solo/análise , Animais , Galinhas/crescimento & desenvolvimento , Chrysanthemum/química , Cadeia Alimentar , Roxarsona/metabolismo
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(4): 1100-3, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-25007637

RESUMO

A method for simultaneous determination of arsanilic, nitarsone and roxarsone (ROX) residues in foods of animal origin was developed by accelerated solvent extraction-liquid chromatography-atomic fluorescence spectrometry (ASE-LC-AFS). The ultrasound centrifugation extraction and accelerated solvent extraction were compared, and the accelerated solvent extraction conditions, namely the proportion of the extraction solvent, the extraction temperature, extraction time and extraction times, were optimized. The operating conditions of LC-AFS and the mobile phase were optimized. Under the optimal conditions, the calibration curves for ASA , NIT and ROX were linear over the concentration range of 0-2.0 mg x L(-1) and their correlation coefficients were 0.999 2-0.999 8. The detection limits of ASA, NIT and ROX were 2.4, 7.4 and 4.1 microg x L(-1) respectively. The average recoveries of ASA, NIT and ROX from two samples spiked at three levels of 0.5, 2, 5 mg x kg(-1) were in the ranges of 87.1%-93.2%, 85.2%-93.9%, and 84.2%-93.7% with RSDs of 1.4%-4.6%, 1.2%-4.2%, and 1.1%-4.5%, respectively. This method possesses the merits of convenience and good repeatability, and is a feasible method for analysis of ASA, NIT and ROX in foods of animal origin.


Assuntos
Ácido Arsanílico/análise , Arsenicais/análise , Cromatografia Líquida , Carne/análise , Roxarsona/análise , Animais , Espectrometria de Fluorescência , Temperatura Ambiente
11.
Environ Sci Technol ; 48(2): 1141-7, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24359149

RESUMO

The toxic metalloid arsenic is widely distributed in food, water, and soil. While inorganic arsenic enters the environment primarily from geochemical sources, methylarsenicals either result from microbial biotransformation of inorganic arsenic or are introduced anthropogenically. Methylarsenicals such as monosodium methylarsonic acid (MSMA) have been extensively utilized as herbicides, and aromatic arsenicals such as roxarsone (Rox) are used as growth promoters for poultry and swine. Organoarsenicals are degraded to inorganic arsenic. The toxicological effects of arsenicals depend on their oxidation state, chemical composition, and bioavailability. Here we report that the active forms are the trivalent arsenic-containing species. We constructed a whole-cell biosensor utilizing a modified ArsR repressor that is highly selective toward trivalent methyl and aromatic arsenicals, with essentially no response to inorganic arsenic. The biosensor was adapted for in vitro detection of organoarsenicals using fluorescence anisotropy of ArsR-DNA interactions. It detects bacterial biomethylation of inorganic arsenite both in vivo and in vitro with detection limits of 10(-7) M and linearity to 10(-6) M for phenylarsenite and 5 × 10(-6) M for methylarsenite. The biosensor detects reduced forms of MSMA and roxarsone and offers a practical, low cost method for detecting activate forms and breakdown products of organoarsenical herbicides and growth promoters.


Assuntos
Arsênico/análise , Arsenicais/análise , Técnicas Biossensoriais/métodos , Crescimento e Desenvolvimento , Herbicidas/análise , Animais , Anti-Infecciosos/análise , Anti-Infecciosos/farmacologia , Arsênico/farmacologia , Arsenicais/farmacologia , Biotransformação , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Crescimento e Desenvolvimento/efeitos dos fármacos , Metilação/efeitos dos fármacos , Mutação/genética , Aves Domésticas/metabolismo , Roxarsona/análise , Roxarsona/farmacologia , Transativadores/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-23859781

RESUMO

Roxarsone is an organoarsenic feed additive that can be metabolised to other higher toxic arsenic (As) species in animal manure such as arsenate, arsenite, monomethylarsonic acid, dimethylarsinic acid, 3-amino-4-hydroxyphenylarsonic acid and other unknown As species. The accumulation, transport and distribution of As species in turnip (Brassica rapa L.) and lettuce (Lactuca sativa L.) amended with roxarsone and its metabolites in chicken manure were investigated. Results showed arsenite was the predominant As form, followed by arsenate in turnip and lettuce plants, and a low content of dimethylarsinic acid was detected only in lettuce roots. Compared with the control plants treated with chicken manure without roxarsone and its metabolites, the treatments containing roxarsone and its metabolites increased arsenite content by 2.0-3.2% in turnip shoots, by 6.6-6.7% in lettuce shoots, by 11-44% in turnip tubers and by 18-20% in lettuce roots at two growth stages. The enhanced proportion of arsenate content in turnip shoots, turnip tubers and lettuce roots was 4.3-14%, 20-35% and 70%, respectively, while dimethylarsinic acid content in lettuce roots increased 2.4 times. Results showed that the occurrence of dimethylarsinic acid in lettuce roots might be converted from the inorganic As species and the uptake of both inorganic and organic As compounds in turnip and lettuce plants would be enhanced by roxarsone and its metabolites in chicken manure. The pathway of roxarsone metabolites introduced into the human body via roxarsone → animal → manure → soil → crop was indicated.


Assuntos
Arsenicais/metabolismo , Brassica rapa/metabolismo , Alface/metabolismo , Esterco , Resíduos de Praguicidas/metabolismo , Roxarsona/metabolismo , Verduras/metabolismo , Ração Animal , Animais , Arsenicais/análise , Disponibilidade Biológica , Brassica napus/química , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Brassica rapa/química , Brassica rapa/crescimento & desenvolvimento , Ácido Cacodílico/análise , Ácido Cacodílico/metabolismo , Galinhas , China , Coccidiostáticos/análise , Coccidiostáticos/metabolismo , Coccidiostáticos/farmacocinética , Fezes/química , Aditivos Alimentares/efeitos adversos , Aditivos Alimentares/análise , Aditivos Alimentares/metabolismo , Aditivos Alimentares/farmacocinética , Contaminação de Alimentos/prevenção & controle , Alface/química , Alface/crescimento & desenvolvimento , Resíduos de Praguicidas/efeitos adversos , Resíduos de Praguicidas/análise , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/crescimento & desenvolvimento , Componentes Aéreos da Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Tubérculos/química , Tubérculos/crescimento & desenvolvimento , Tubérculos/metabolismo , Roxarsona/efeitos adversos , Roxarsona/análise , Roxarsona/farmacocinética , Verduras/química , Verduras/crescimento & desenvolvimento
13.
Environ Health Perspect ; 121(7): 818-24, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23694900

RESUMO

BACKGROUND: Inorganic arsenic (iAs) causes cancer and possibly other adverse health outcomes. Arsenic-based drugs are permitted in poultry production; however, the contribution of chicken consumption to iAs intake is unknown. OBJECTIVES: We sought to characterize the arsenic species profile in chicken meat and estimate bladder and lung cancer risk associated with consuming chicken produced with arsenic-based drugs. METHODS: Conventional, antibiotic-free, and organic chicken samples were collected from grocery stores in 10 U.S. metropolitan areas from December 2010 through June 2011. We tested 116 raw and 142 cooked chicken samples for total arsenic, and we determined arsenic species in 65 raw and 78 cooked samples that contained total arsenic at ≥ 10 µg/kg dry weight. RESULTS: The geometric mean (GM) of total arsenic in cooked chicken meat samples was 3.0 µg/kg (95% CI: 2.5, 3.6). Among the 78 cooked samples that were speciated, iAs concentrations were higher in conventional samples (GM = 1.8 µg/kg; 95% CI: 1.4, 2.3) than in antibiotic-free (GM = 0.7 µg/kg; 95% CI: 0.5, 1.0) or organic (GM = 0.6 µg/kg; 95% CI: 0.5, 0.8) samples. Roxarsone was detected in 20 of 40 conventional samples, 1 of 13 antibiotic-free samples, and none of the 25 organic samples. iAs concentrations in roxarsone-positive samples (GM = 2.3 µg/kg; 95% CI: 1.7, 3.1) were significantly higher than those in roxarsone-negative samples (GM = 0.8 µg/kg; 95% CI: 0.7, 1.0). Cooking increased iAs and decreased roxarsone concentrations. We estimated that consumers of conventional chicken would ingest an additional 0.11 µg/day iAs (in an 82-g serving) compared with consumers of organic chicken. Assuming lifetime exposure and a proposed cancer slope factor of 25.7 per milligram per kilogram of body weight per day, this increase in arsenic exposure could result in 3.7 additional lifetime bladder and lung cancer cases per 100,000 exposed persons. CONCLUSIONS: Conventional chicken meat had higher iAs concentrations than did conventional antibiotic-free and organic chicken meat samples. Cessation of arsenical drug use could reduce exposure and the burden of arsenic-related disease in chicken consumers.


Assuntos
Arsenicais/metabolismo , Exposição Ambiental , Poluentes Ambientais/metabolismo , Neoplasias Pulmonares/epidemiologia , Carne/análise , Neoplasias da Bexiga Urinária/epidemiologia , Animais , Arsenicais/administração & dosagem , Arsenicais/análise , Galinhas/metabolismo , Cromatografia Líquida de Alta Pressão/veterinária , Coccidiostáticos/administração & dosagem , Coccidiostáticos/análise , Coccidiostáticos/metabolismo , Culinária , Poluentes Ambientais/administração & dosagem , Poluentes Ambientais/análise , Humanos , Neoplasias Pulmonares/induzido quimicamente , Espectrometria de Massas/veterinária , Músculos Peitorais/metabolismo , Medição de Risco , Roxarsona/administração & dosagem , Roxarsona/análise , Roxarsona/metabolismo , Estados Unidos/epidemiologia , Neoplasias da Bexiga Urinária/induzido quimicamente
14.
Huan Jing Ke Xue ; 34(2): 732-9, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23668148

RESUMO

Seventy chicken and seventy-six pig feeds were collected from the feed stores in Guangdong province, and the species and concentrations of As, Cu and Zn were determined. We also examined the stability of roxarsone (ROX), one of the most widely used organoarsenical additives, either in the additive or in the feed at room temperature. The results showed that, averagely, the chicken and pig feeds contained 3.6 and 6.5 mg.kg-1 (As), 18.2 and 119.4 mg.kg-1 (Cu),and 124.6 and 486.2 mg.kg-1 (Zn), respectively. The excessive dosages of As, Cu and As in animal feeds will lead to higher residue of As, Cu and Zn in animal manures. Based on the national limit criteria for feed or feed additive, it was supposed that organoarsenicals had been used, only few feed samples exceeded the As limit, however, the excessive Cu and Zn in pig feeds were much more common. Organoarsenicals were found in 25.4% of the total feed samples, and As(Ill) and As(V) were the two most commonly detected As impurities in feeds bearing organoarsenicals. The mean detectable ROX and arsenilic acid were 7.0 and 21.2 mg.kg-1, respectively. Organoarsenicals were detectable in 24. 3% of the chicken feed samples and 26. 3% of the pig feed samples. Moreover, ROX was commonly used in chicken feeds, while p-ASA in pig feeds. ROX and the inorganic As impurities, either in the commercial additive or in the feed, remained stable for at least 30 days at room temperature, indicating the higher As impurities in feeds probably originated from the As impurities in organoarsenical additives. This is a new As exposure pathway for the producer and user of organoarsenicals and feeds amending organoarsenicals.


Assuntos
Ração Animal/análise , Arsênico/análise , Cobre/análise , Zinco/análise , Animais , Galinhas , China , Roxarsona/análise , Suínos
15.
J Agric Food Chem ; 61(20): 4676-91, 2013 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-23662936

RESUMO

The Agrochemicals Division symposium "Perfecting Communication of Chemical Risk", held at the 244th National Meeting and Exposition of the American Chemical Society in Philadelphia, PA, August 19-23, 2012, is summarized. The symposium, organized by James Seiber, Kevin Armbrust, John Johnston, Ivan Kennedy, Thomas Potter, and Keith Solomon, included discussion of better techniques for communicating risks, lessons from past experiences, and case studies, together with proposals to improve these techniques and their communication to the public as effective information. The case studies included risks of agricultural biotechnology, an organoarsenical (Roxarsone) in animal feed, petroleum spill-derived contamination of seafood, role of biomonitoring and other exposure assessment techniques, soil fumigants, implications of listing endosulfan as a persistant organic pollutant (POP), and diuron herbicide in runoff, including use of catchment basins to limit runoff to coastal ecozones and the Great Barrier Reef. The symposium attracted chemical risk managers including ecotoxicologists, environmental chemists, agrochemists, ecosystem managers, and regulators needing better techniques that could feed into better communication of chemical risks. Policy issues related to regulation of chemical safety as well as the role of international conventions were also presented. The symposium was broadcast via webinar to an audience outside the ACS Meeting venue.


Assuntos
Agroquímicos/efeitos adversos , Disseminação de Informação/métodos , Ração Animal/análise , Animais , Austrália , Biotecnologia , Diurona/análise , Endossulfano/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Fumigação/efeitos adversos , Praguicidas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Aves Domésticas , Medição de Risco , Fatores de Risco , Roxarsona/análise , Alimentos Marinhos/análise
16.
Appl Spectrosc ; 65(4): 423-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21396190

RESUMO

Organoarsenic drugs such as roxarsone and 4-arsanilic acid are poultry feed additives widely used in US broilers to prevent coccidosis and to enhance growth and pigmentation. Despite their veterinary benefits there has been growing concern about their use because over 90% of these drugs are released intact into litter, which is often sold as a fertilizing supplement. The biochemical degradation of these antimicrobials in the litter matrix can release significant amounts of soluble As(III) and As(V) to the environment, representing a potential environmental risk. Silver/polydimethylsiloxane (Ag/PDMS) nanocomposites are a class of surfaceenhanced Raman scattering (SERS) substrates that have proven effective for the sensitive, reproducible, and field-adaptable detection of aromatic acids in water. The work presented herein uses for the first time Ag/PDMS nanocomposites as substrates for the detection and characterization of trace amounts of roxarsone, 4-arsanilic acid, and acetarsone in water. The results gathered in this study show that organoarsenic species are distributed into the PDMS surface where the arsonic acid binds onto the embedded silver nanoparticles, enhancing its characteristic 792 cm(-1) stretching band. The chemisorption of the drugs to the metal facilitates its detection and characterization in the parts per million to parts per billion range. An extensive analysis of the distinct spectroscopic features of each drug is presented with emphasis on the interactions of the arsonic acid, amino, and nitro groups with the metal surface. The benefits of SERS based methods for the study of arsenic drugs are also discussed.


Assuntos
Antibacterianos/análise , Arsenicais/análise , Dimetilpolisiloxanos/química , Nanocompostos/química , Análise Espectral Raman/métodos , Ração Animal , Antibacterianos/química , Ácido Arsanílico/análise , Ácido Arsanílico/química , Arsenicais/química , Monitoramento Ambiental , Nanopartículas Metálicas/química , Roxarsona/análise , Roxarsona/química , Prata/química
17.
Ann N Y Acad Sci ; 1140: 346-57, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18991934

RESUMO

Arsenic exposures contribute significantly to the burden of preventable disease worldwide, specifically related to increased risks of cancer, diabetes, and cardiovascular disease. Most exposures are associated with natural contamination of groundwater, which is difficult to mitigate when these sources are used for drinking water. An anthropogenic source of arsenic exposure stems from the widespread use of arsenical drugs in food-animal production in the United States and China, among many countries. This use results in residual contamination of food products from animals raised with the drugs, as well as environmental contamination associated with disposal of wastes from these animals. Land disposal of these wastes can contaminate surface and ground water, and the conversion of animal wastes into fertilizer pellets for home use as well as the introduction of animal waste incinerators may increase opportunities for exposure. As an intentional additive to animal feed, use of arsenical drugs is a preventable source of human exposure. The domestic practice of using these drugs in poultry production has been the subject of media attention and limited research, though the use of these drugs in domestic swine production and in the rapidly growing foreign animal production industry remains largely uncharacterized. This continued expansion of arsenical drug use may likely increase the burden of global human arsenic exposure and risk.


Assuntos
Ração Animal , Meio Ambiente , Animais , Arsênico , Intoxicação por Arsênico/prevenção & controle , Desinfetantes , Saúde Ambiental , Monitoramento Ambiental , Análise de Alimentos , Contaminação de Alimentos , Exposição Ocupacional , Saúde Pública , Eliminação de Resíduos , Risco , Roxarsona/análise
18.
Environ Sci Technol ; 41(3): 818-23, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17328188

RESUMO

The extensive use of 3-nitro-4-hydroxybenzene arsonic acid (roxarsone) in the production of broiler chickens can lead to increased soil arsenic concentration and arsenic contaminated dust. While roxarsone is the dominant arsenic species in fresh litter, inorganic As (V) predominates in composted litter. Microbial activity has been implicated as the cause, but neither the specific processes nor the organisms have been identified. Here we demonstrate the rapid biotransformation of roxarsone under anaerobic conditions by Clostridium species in chicken litter enrichments and a pure culture of a fresh water arsenate respiring species (Clostridium sp. strain OhILAs). The main products were 3-amino-4-hydroxybenzene arsonic acid and inorganic arsenic. Growth experiments and genomic analysis indicate strain OhILAs may use roxarsone as a terminal electron acceptor for anaerobic respiration. Electronic structure analysis suggests that the reducing equivalents should go to the nitro group, while liberation of inorganic arsenic from the intact benzene ring by cleaving the C-As bond is unlikely. Clostridium and Lactobacillus species are common in the chicken cecum and litter. Thus, the organic-rich manure and anaerobic conditions typically associated with composting provide the conditions necessary for the native microbial populations to transform the roxarsone in the litter releasing the more toxic inorganic arsenic.


Assuntos
Arsênico/metabolismo , Biotransformação , Clostridium/metabolismo , Roxarsona/metabolismo , Poluentes do Solo/metabolismo , Anaerobiose , Animais , Antibacterianos/análise , Antibacterianos/química , Antibacterianos/metabolismo , Arsênico/análise , Arsênico/química , Benzeno/química , Ceco/microbiologia , Galinhas , Monitoramento Ambiental , Genômica , Lactobacillus/metabolismo , Esterco/microbiologia , Nitrocompostos/química , Roxarsona/análise , Roxarsona/química , Poluentes do Solo/análise , Poluentes do Solo/química
19.
Environ Sci Technol ; 40(9): 2951-7, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16719096

RESUMO

Large quantities of arsenic are introduced into the environment through land application of poultry litter containing the organoarsenical feed additive roxarsone (3-nitro-4-hydroxyphenylarsonic acid). The objective of this study was to evaluate the bioconversion of roxarsone and related N-substituted phenylarsonic acid derivatives under anaerobic conditions. The results demonstrate that roxarsone is rapidly transformed in the absence of oxygen to the corresponding aromatic amine, 4-hydroxy-3-aminophenylarsonic acid (HAPA). The formation of HAPA is attributable to the facile reduction of the nitro group. Electron-donating substrates, such as hydrogen gas, glucose, and lactate, stimulated the rate of nitro group reduction, indicating a microbial role. During long-term incubations, HAPA and the closely related 4-aminophenylarsonic acid (4-APA) were slowly biologically eliminated by up to 99% under methanogenic and sulfate-reducing conditions, whereas little or no removal occurred in heat-killed inoculum controls. Arsenite and, to a lesser extent, arsenate were observed as products of the degradation. Freely soluble forms of the inorganic arsenical species accounted for 19-28% of the amino-substituted phenylarsonic acids removed. This constitutes the first report of a biologically catalyzed rupture of the phenylarsonic group under anaerobic conditions.


Assuntos
Arsenicais/análise , Roxarsona/análise , Arsênico/toxicidade , Arsenicais/química , Arsenitos/análise , Bactérias Anaeróbias/metabolismo , Biodegradação Ambiental , Biotransformação , Catálise , Elétrons , Monitoramento Ambiental , Temperatura Alta , Eliminação de Resíduos , Poluentes do Solo , Eliminação de Resíduos Líquidos , Poluentes da Água
20.
Electrophoresis ; 26(7-8): 1606-14, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15761918

RESUMO

The determination of the animal feed additive roxarsone (3-nitro-4-hydroxyphenylarsonic acid) and six of its possible transformation products (arsenite, arsenate, monomethylarsonate, dimethylarsinate, 3-amino-4-hydroxyphenylarsonic acid, and 4-hydroxyphenylarsonic acid) in chicken manure was investigated using capillary electrophoresis-inductively coupled plasma-mass spectrometry (CE-ICP-MS). Initial method development was conducted using ultraviolet (UV) detection for ruggedness and time efficiency. Separation of these seven arsenic species was effected using a 20 mM phosphate buffer at pH 5.7. The CE-ICP-MS limits of detection in terms of As for each of the species was in the low microg.L(-1) range, corresponding to absolute detection limits in the range 20-70 fg As (based on a 23 nL injection). Overall, the method developed in this study provides high selectivity and low limits of detection (1-3 microg.L(-1) or low-ppb, based on As), uses small sample volume (low nL), and produces minimal wastes.


Assuntos
Coccidiostáticos/análise , Eletroforese Capilar/métodos , Esterco/análise , Espectrometria de Massas/métodos , Roxarsona/análise , Animais , Galinhas , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
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