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1.
Braz. j. biol ; 82: 1-7, 2022. graf, tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468494

RESUMEN

Agroecological production represents a new reality in vegetable farming. Thus, the study aimed to search for the presence of pesticides in agroecological samples and microbiological and parasitological contamination in Lactuca sativa L. of agroecological and conventional fairs in Alagoas. Thirty-two samples were collected, a hygienic sanitary checklist was performed, along with coliform, Salmonella spp., Staphylococcus aureus research and Gas Chromatography with Mass Spectrometer (GC-MS) for pesticide research; using two methodologies for parasitological studies. Thirty-two samples were analyzed, with a sanitary adequacy level at 45% and 38% for fairs (agroecological and conventional) respectively, with three samples (9.4%) in total, being adequate to the microbiological pattern according to RDC no. 12/2001. Among the 23 samples which were tested positive for parasites, 69.5% originated from samples extracted at conventional fairs, and 53% of every positive samples presented Entamoeba coli as the main contaminant. All together, no traces of deltamethrin were detected, but in two of the samples a peak retention for diphenoconazole was detected. In conclusion, the fairs represent an adequate environment for human pathogens and indicators. Therefore greater hygiene training of vegetable traders and consumers in the state of Alagoa sis required, especially in conventional fairs, which presented more critical microbiological and parasitological indexes comparing to fairs with agroecological products; however, the presence of difenoconazole in two samples of agricultural fairs suggests accidental contamination or indiscriminate use of this chemical in the production of Lactuca sativa, however, products with agroecological origin represents a better choice for the consumers.


A produção agroecológica representa uma nova realidade no cultivo das hortaliças. Assim, o estudo teve como objetivo verificar a presença de agrotóxicos em amostras agroecológicas e analisar a contaminação microbiológico e parasitológico em Lactuca sativa L. de feiras agroecológicas e convencionais de Alagoas. Foram coletadas 32 amostras, realizando checklist higiênico-sanitário, análises de coliformes, Salmonella spp., Staphylococcus aureus e Cromatografia Gasosa com Espectrômetro de Massas (GC-MS) para pesquisa de agrotóxicos; utilizando-se duas metodologias para estudos parasitológicos. Foram analisadas 32 amostras, com nível de adequação sanitária de 45% e 38% para feiras (agroecológicas e convencionais) respectivamente, sendo três amostras no total (9,4%) adequadas a padrão microbiológico segundo RDC n° 12//2001; Dentre as 23 amostras positivas para parasitos, 69,5% teve origem em amostras de feiras convencionais, e 53% de todas as amostras positivas apresentaram Entamoeba coli como principal contaminante, juntamente, não foi detectado traços de deltametrina, porem foi visualizado em duas amostras, pico de retenção para padrão de difenoconazol. Concluindo-se que as feiras representam um ambiente adequado para patógenos humanos e indicadores, necessitando de uma maior higienização e treinamento dos comerciantes e consumidores de hortaliças do estado de Alagoas, principalmente em feiras convencionais, que apresentaram índices microbiológicos e parasitológicos mais críticos em relação a feiras com produtos agroecológicos; mas, a presença de difenoconazole em duas amostras de feiras agroecológicas sugerem contaminação acidental ou uso indiscriminado deste químico em produção da Lactuca sativa L., todavia os produtos de origem agroecológica representam uma melhor escolha para o consumidor.


Asunto(s)
Animales , Agroquímicos/análisis , Lactuca/microbiología , Lactuca/parasitología , Coliformes , Salmonella , Staphylococcus aureus , Cromatografía de Gases y Espectrometría de Masas
2.
Environ Pollut ; 228: 297-304, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28551560

RESUMEN

Garden centres frequently market nectar- and pollen-rich ornamental plants as "pollinator-friendly", however these plants are often treated with pesticides during their production. There is little information on the nature of pesticide residues present at the point of purchase and whether these plants may actually pose a threat to, rather than benefit, the health of pollinating insects. Using mass spectrometry analyses, this study screened leaves from 29 different 'bee-friendly' plants for 8 insecticides and 16 fungicides commonly used in ornamental production. Only two plants (a Narcissus and a Salvia variety) did not contain any pesticide and 23 plants contained more than one pesticide, with some species containing mixtures of 7 (Ageratum houstonianum) and 10 (Erica carnea) different agrochemicals. Neonicotinoid insecticides were detected in more than 70% of the analysed plants, and chlorpyrifos and pyrethroid insecticides were found in 10% and 7% of plants respectively. Boscalid, spiroxamine and DMI-fungicides were detected in 40% of plants. Pollen samples collected from 18 different plants contained a total of 13 different pesticides. Systemic compounds were detected in pollen samples at similar concentrations to those in leaves. However, some contact (chlorpyrifos) and localised penetrant pesticides (iprodione, pyroclastrobin and prochloraz) were also detected in pollen, likely arising from direct contamination during spraying. The neonicotinoids thiamethoxam, clothianidin and imidacloprid and the organophosphate chlorpyrifos were present in pollen at concentrations between 6.9 and 81 ng/g and at levels that overlap with those known to cause harm to bees. The net effect on pollinators of buying plants that are a rich source of forage for them but simultaneously risk exposing them to a cocktail of pesticides is not clear. Gardeners who wish to gain the benefits without the risks should seek uncontaminated plants by growing their own from seed, plant-swapping or by buying plants from an organic nursery.


Asunto(s)
Monitoreo del Ambiente , Insectos/efectos de los fármacos , Residuos de Plaguicidas/análisis , Agroquímicos/análisis , Animales , Abejas , Fungicidas Industriales/análisis , Jardinería , Guanidinas/análisis , Imidazoles/análisis , Insecticidas/análisis , Neonicotinoides , Nitrocompuestos/análisis , Oxazinas/análisis , Plaguicidas/análisis , Néctar de las Plantas/química , Polen/química , Polinización/efectos de los fármacos , Semillas/química , Tiametoxam , Tiazoles/análisis
3.
BMC Complement Altern Med ; 17(1): 154, 2017 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-28288606

RESUMEN

BACKGROUND: Asian traditional herbal preparations are frequently considered for the contamination with undeclared toxic or hazardous substances. The aim of this study was to determine the toxic heavy metals, pesticides and sulfur dioxide in decoctions that is a common form of final utilization in Korea. METHODS: A total of 155 decoctions composed of multi-ingredient traditional herbs were randomly sampled from Seoul in Korea between 2013 and 2014. For each decoction, the concentrations of four heavy metals (arsenic, cadmium, lead and mercury), 33 pesticides and sulfur dioxide were analyzed using inductively coupled plasma mass spectrometry (ICP-MS), mercury analyzer, gas chromatography/nitrogen phosphorous detector (GC/NPD), gas chromatography/micro electron capture detector (GC/µECD), and Monier-Williams method respectively. RESULTS: One hundred fifty-two of One hundred fifty-five decoctions (98.1%) contained one of three heavy metals (96.1% for As, 97.4% for Cd, and 90.3% for Pb, 0.0% for Hg). Their average concentrations (77.0 ± 79.7 ug/kg for As, 20.4 ± 23.7 ug/kg for Cd, and 68.8 ± 76.5 ug/kg for Pb) were approximately 20% of the maximum allowable limits of vegetable or ginseng beverage described in the Korean Food Standard Codex while their 95th percentile concentrations were below than the guideline for them. None of 33 pesticides was detected in 155 decoction samples, and only one sample showed over limit of detection for residual sulfites. CONCLUSIONS: This study support that the contained status of toxic heavy metals, pesticides and sulfur dioxide in herbal decoctions are currently within safe level in Korea, and provide a reference data for the further studies focused on the safety herbal preparations.


Asunto(s)
Agroquímicos/análisis , Contaminación de Medicamentos/estadística & datos numéricos , Metales Pesados/análisis , Extractos Vegetales/análisis , Plantas Medicinales/química , Sulfitos/análisis , Espectrometría de Masas , Residuos de Plaguicidas/análisis , República de Corea
4.
Rev. bras. plantas med ; 18(2): 563-569, 2016. tab
Artículo en Portugués | LILACS | ID: lil-787939

RESUMEN

RESUMO O maracujá-amarelo (Passiflora edulis f. flavicarpa Deg) é considerado um alimento funcional, visto que, além de funções nutricionais, desempenha ações em vias metabólicas específicas. A farinha da casca do maracujá-amarelo (Passiflora edulis f. flavicarpa Deg) é rica em pectina. Esta fibra reduz a absorção de glicídios e lipídios, influenciando no metabolismo destes nutrientes. Portadores de patologias associadas às alterações no metabolismo glicêmico e lipidêmico têm utilizado este recurso de forma indiscriminada. Porém, substâncias designadas glicosídeos cianogênicos, presentes na casca do fruto são tóxicas ao organismo e prejudiciais à saúde. Ademais, o uso exacerbado de agrotóxicos na produção do maracujá é preocupante e a ingestão destes compostos também pode acarretar complicações à saúde. Portanto, o objetivo do presente trabalho foi sintetizar o conhecimento disponível referente aos efeitos terapêuticos e colaterais da suplementação com a farinha da casca do maracujá-amarelo (Passiflora edulis f. flavicarpa Deg). Foi realizada uma revisão bibliográfica nas bases de dados indexadas SCIELO, LILACS e PUBMED, sem limitação quanto ao período de publicação. Os estudos inclusos no trabalho, de forma unânime, apresentam eficácia da suplementação com a farinha da casca do maracujá-amarelo. A trituração da casca do fruto, realizada no processo de obtenção da farinha, é incapaz de promover redução de glicosídeos cianogênicos e agrotóxicos, permitindo que os indivíduos submetidos à suplementação estejam susceptíveis aos efeitos tóxicos destes compostos. Dessa forma, o desenvolvimento de estudos que avaliem a toxicidade da suplementação por períodos crônicos é de suma importância. Referente ao uso de agrotóxicos, a produção da farinha com frutos orgânicos pode ser uma alternativa para atenuar a toxicidade, sendo necessária a elucidação desta hipótese através de estudos.


ABSTRACT The yellow passion fruit (Passiflora edulis f. flavicarpa Deg) is considered a functional food, because, in addition to nutritional functions, it performs actions in specific metabolic pathways. The yellow passion fruit peel flour (Passiflora edulis f. flavicarpa Deg) is rich in pectin. This fiber reduces the absorption of carbohydrates and lipids, influencing the metabolism of these nutrients. Individuals affected by pathologies associated with alterations in the metabolism of lipids and carbohydrates have used this resource indiscriminately, however, substances called cyanogenic glycosides, present in the fruit peel, are toxic to the body and harmful to health. In addition, the overuse of pesticides in passion fruit production is becoming worrisome and the ingestion of these compounds can also cause negative health implications. Therefore, the aim of this study was to synthesize the available knowledge regarding the therapeutic effects and side effects of supplementation with the yellow passion fruit peel flour (Passiflora edulis f. flavicarpa Deg). A literature review was conducted from the indexed databases SCIELO, LILACS and PUBMED, without limitation to the publication period. The studies included in the work, unanimously, have effectiveness of supplementation with yellow passion fruit peel flour (Passiflora edulis f. flavicarpa Deg). The crushing of the fruit peel, performed in the process of obtaining flour, is unable to promote a reduction of cyanogenic glycosides and pesticides, causing individuals undergoing supplementation to be susceptible to the toxic effects of these compounds. Thus, this study’s development to evaluate the toxicity of supplementation for chronic periods is very important. With reference to the use of pesticides, flour production with organic fruits can be an alternative to attenuate toxicity and it is necessary to elucidate this hypothesis through this study.


Asunto(s)
Agroquímicos/análisis , Passiflora/clasificación , Toxicidad , Cianuros/análisis
5.
Environ Manage ; 54(2): 223-39, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24844463

RESUMEN

Everglades restoration is dependent on constructed wetlands to treat agricultural phosphorus (P)-enriched runoff prior to delivery to the Everglades. Over the last 5 years, P concentrations delivered to the northern boundary of Everglades National Park (Park) have remained higher than the 8 µg L(-1)-target identified to be protective of flora and fauna. Historically, Everglades hydrology was driven by rainfall that would then sheetflow through the system. The system is now divided into a number of large impoundments. We use sodium-to-calcium ratios as a water source discriminator to assess the influence of management and environmental conditions to understand why P concentrations in Park inflows remain higher than that of the target. Runoff from Water Conservation Area 3A (Area 3A) and canal water from areas north of Area 3A are two major sources of water to the Park, and both have distinct Na:Ca ratios. The P concentrations of Park inflows have decreased since the 1980s, and from June 1994 through May 2000, concentrations were the lowest when Area 3A water depths were the deepest. Area 3A depths declined following this period and P concentrations subsequently increased. Further, some water sources for the Park are not treated and are impeding concentration reductions. Promoting sheetflow over channelized flow and treating untreated water sources can work in conjunction with constructed wetlands to further reduce nutrient loading to the sensitive Everglades ecosystem.


Asunto(s)
Agroquímicos/análisis , Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente/estadística & datos numéricos , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , Humedales , Calcio/análisis , Florida , Sodio/análisis , Estadísticas no Paramétricas , Factores de Tiempo
6.
Toxicol Lett ; 227(1): 20-8, 2014 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-24657160

RESUMEN

The identification of the no observed adverse effect level (NOAEL) is the key regulatory outcome of toxicity studies. With the introduction of "omics" technologies into toxicological research, the question arises as to how sensitive these technologies are relative to classical regulatory toxicity parameters. BASF SE and metanomics developed the in vivo metabolome database MetaMap®Tox containing metabolome data for more than 500 reference compounds. For several years metabolome analysis has been routinely performed in regulatory toxicity studies (REACH mandated testing or new compound development), mostly in the context of 28 day studies in rats (OECD 407 guideline). For those chemicals for which a toxicological NOAEL level was obtained at either high or mid-dose level, we evaluated the associated metabolome to investigate the sensitivity of metabolomics versus classical toxicology with respect to the NOAEL. For the definition of a metabolomics NOAEL the ECETOC criteria (ECETOC, 2007) were used. In this context we evaluated 104 cases. Comparable sensitivity was noted in 75% of the cases, increased sensitivity of metabolomics in 8%, and decreased sensitivity in 18% of the cases. In conclusion, these data suggest that metabolomics profiling has a similar sensitivity to the classical toxicological study (e.g. OECD 407) design.


Asunto(s)
Agroquímicos/toxicidad , Evaluación Preclínica de Medicamentos , Drogas en Investigación/efectos adversos , Metabolómica/métodos , Modelos Biológicos , Pruebas de Toxicidad , Agroquímicos/análisis , Agroquímicos/farmacocinética , Animales , Bases de Datos de Compuestos Químicos , Evaluación Preclínica de Medicamentos/normas , Drogas en Investigación/análisis , Drogas en Investigación/farmacocinética , Femenino , Alemania , Guías como Asunto , Humanos , Legislación de Medicamentos , Masculino , Nivel sin Efectos Adversos Observados , Medicamentos sin Prescripción/efectos adversos , Medicamentos sin Prescripción/análisis , Medicamentos sin Prescripción/farmacocinética , Medicamentos bajo Prescripción/efectos adversos , Medicamentos bajo Prescripción/análisis , Medicamentos bajo Prescripción/farmacocinética , Ratas , Ratas Wistar , Reproducibilidad de los Resultados , Caracteres Sexuales , Pruebas de Toxicidad/normas , Toxicología/legislación & jurisprudencia , Toxicología/métodos
7.
Sci Total Environ ; 468-469: 1178-86, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23579204

RESUMEN

Managing phosphorus in catchments is central to improving surface water quality, but knowing how much can be mitigated from agricultural land, and at what cost relative to a natural baseline (or reference condition), is difficult to assess. The difference between median concentrations now and under reference was defined as the anthropogenic loss, while the manageable loss was defined as the median P concentration possible without costing more than 10% of farm profitability (measured as earnings before interest and tax, EBIT). Nineteen strategies to mitigate P loss were ranked according to cost (low, medium, high, very high). Using the average dairy and drystock farms in 14 grassland catchments as test cases, the potential to mitigate P loss from land to water was then modelled for different strategies, beginning with strategies within the lowest cost category from best to least effective, before applying a strategy from a more expensive category. The anthropogenic contribution to stream median FRP and TP concentrations was estimated as 44 and 69%, respectively. However, applying up to three strategies per farm theoretically enabled mitigation of FRP and TP losses sufficient to maintain aesthetic and trout fishery values to be met and at a cost <1% EBIT for drystock farms and <6% EBIT for dairy farms. This shows that defining and acting upon the manageable loss in grassland catchments (with few point sources) has potential to achieve a water quality outcome within an ecological target at little cost.


Asunto(s)
Agricultura/métodos , Seguimiento de Parámetros Ecológicos/métodos , Fósforo/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Contaminación del Agua/prevención & control , Calidad del Agua/normas , Agroquímicos/análisis , Nueva Zelanda , Fósforo/metabolismo , Poaceae/metabolismo , Suelo/química
8.
Sci Total Environ ; 468-469: 1255-66, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24060142

RESUMEN

The EU Water Framework Directive (WFD) obliges Member States to improve the quality of surface water and groundwater. The measures implemented to date have reduced the contribution of point sources of pollution, and hence diffuse pollution from agriculture has become more important. In many catchments the water quality remains poor. COST Action 869 was an EU initiative to improve surface water quality that ran from 2006 to 2011, in which 30 countries participated. Its main aim was a scientific evaluation of the suitability and cost-effectiveness of options for reducing nutrient loss from rural areas to surface waters at catchment scale, including the feasibility of the options under different climatic and geographical conditions. This paper gives an overview of various categories of mitigation options in relation to phosphorus (P). The individual measures are described in terms of their mode of action, applicability, effectiveness, time frame, environmental side-effects (N cycling) and cost. In total, 83 measures were evaluated in COST Action 869.


Asunto(s)
Agricultura/métodos , Agroquímicos/análisis , Conservación de los Recursos Naturales/métodos , Fósforo/análisis , Movimientos del Agua , Contaminación Química del Agua/prevención & control , Calidad del Agua/normas
9.
J Environ Monit ; 12(6): 1307-14, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20523930

RESUMEN

Rivers Bourne and Hogsmill, urban tributaries of the Thames, were sampled up and downstream of sewage treatment works (STWs) wastewaters outflows. River water was analysed for total phosphorus (TP) and soluble reactive phosphorus (SRP) and, in conjunction with river flow data, this study aimed to assess the impact of treated wastewaters on P concentrations in rivers where wastewater volumes frequently exceed those of the underlying river and to consider whether these rivers are likely to achieve "good ecological status" under the Water Framework Directive (WFD). P concentrations downstream of the STW discharge points were generally an order of magnitude greater than upstream, the flow weighted mean concentration in the River Bourne increased from 0.078 mg SRP l(-1) to 0.45 mg SRP l(-1) downstream of the input source. In the Hogsmill, the flow weighted mean concentration rose from 0.19 mg SRP l(-1) to 1.78 mg SRP l(-1) downstream of the input source prior to the introduction of P removal at the STW. Once P removal commenced, flow weighted mean concentrations downstream of the STW reduced to 0.56 mg SRP l(-1). Headwaters in the River Bourne, upstream of the STW outflow showed evidence of irregular, minor, diffuse inputs but overall mean figures indicate that the proposed UK Technical Advisory Group (UK TAG) for the WFD limit of 0.12 mg SRP l(-1) would be met. Headwaters in the Hogsmill are subject to small, continuous discharges of sewage effluent, sufficient to raise SRP levels above the UK TAG limit. Downstream, neither river meets the UKTAG recommendations in terms of P, despite the use of P-stripping processes at both STWs, an indication that current discharge consents for P concentrations in wastewaters are too high.


Asunto(s)
Monitoreo del Ambiente , Fósforo/análisis , Ríos/química , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/análisis , Agroquímicos/análisis , Ciudades , Inglaterra , Movimientos del Agua
10.
Pest Manag Sci ; 66(3): 238-47, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19937917

RESUMEN

This paper describes the recent progress of in vivo biological screening for pesticides in China. According to the criteria, including the severity of damage caused by pests and the economic value of the crops, the investigated insects, pathogens, herbs and other species in the agricultural field were selected as the main screening targets for pesticides. Corresponding in vivo microscreening methods have been established and applied in the pesticide screening procedure, which has higher reproducibility, a shorter time and greater efficiency that offset the drawbacks of conventional methods for pesticide screening.


Asunto(s)
Agroquímicos/análisis , Evaluación Preclínica de Medicamentos/métodos , Agroquímicos/farmacología , Animales , China , Humanos , Plaguicidas/análisis , Plaguicidas/farmacología , Reguladores del Crecimiento de las Plantas/análisis , Reguladores del Crecimiento de las Plantas/farmacología
11.
Sci Total Environ ; 407(12): 3772-83, 2009 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-19324395

RESUMEN

Phosphorus (P) enrichment has been observed in the historic oligotrophic Greater Everglades in Florida mainly due to P influx from upstream, agriculturally dominated, low relief drainage basins of the Everglades Agricultural Area (EAA). Our specific objectives were to: (1) investigate relationships between various environmental factors and P loads in 10 farm basins within the EAA, (2) identify those environmental factors that impart major effects on P loads using three different tree-based modeling approaches, and (3) evaluate predictive models to assess P loads. We assembled thirteen environmental variable sets for all 10 sub-basins characterizing water level management, cropping practices, soils, hydrology, and farm-specific properties. Drainage flow and P concentrations were measured at each sub-basin outlet from 1992-2002 and aggregated to derive monthly P loads. We used three different tree-based models including single regression trees (ST), committee trees in Bagging (CTb) and ARCing (CTa) modes and ten-fold cross-validation to test prediction performances. The monthly P loads (MPL) during the monitoring period showed a maximum of 2528 kg (mean: 103 kg) and maximum monthly unit area P loads (UAL) of 4.88 kg P ha(-1) (mean: 0.16 kg P ha(-1)). Our results suggest that hydrologic/water management properties are the major controlling variables to predict MPL and UAL in the EAA. Tree-based modeling was successful in identifying relationships between P loads and environmental predictor variables on 10 farms in the EAA indicated by high R(2) (>0.80) and low prediction errors. Committee trees in ARCing mode generated the best performing models to predict P loads and P loads per unit area. Tree-based models had the ability to analyze complex, non-linear relationships between P loads and multiple variables describing hydrologic/water management, cropping practices, soil and farm-specific properties within the EAA.


Asunto(s)
Agroquímicos/análisis , Monitoreo del Ambiente/métodos , Modelos Estadísticos , Fósforo/análisis , Análisis de Regresión , Contaminantes Químicos del Agua/análisis
12.
Sci Total Environ ; 407(12): 3883-9, 2009 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-19324397

RESUMEN

The intensive agricultural systems in the Midwestern United States can enrich surface waters with nutrients. Agricultural drainage ditches serve as the first and second order streams throughout much of this region, as well as other highly productive agricultural areas in humid regions throughout the world. This project was conducted to evaluate in-stream processing of soluble P (SP) in agricultural drainage ditches. Soluble P injection studies were conducted at seven sites along three drainage ditches (298 to 4300 ha drainage area), and one site on a third-order stream that receives the discharge from the agricultural ditches (19,000 ha drainage area) by increasing the SP concentration in the ditch water by approximately 0.25 mg L(-1). Sediments collected from smaller watersheds contained greater amounts of Mehlich 3 and exchangeable P (ExP), silt and clay size particles, and organic matter. Phosphorus uptake lengths (S(net)) ranged from 40 to 1900 m, and SP uptake rates (U) ranged from 0.4 to 52 mg m(-2) h(-1). Phosphorus S(net) was correlated with ditch geomorphological (i.e. width) and sediment properties (i.e. organic matter, ExP, and equilibrium P concentration; r(2)=1.00, P<0.001), indirect drainage in the watershed (r(2)=0.92, P<0.001), and the amount of small grains, forest, urban area, alfalfa and corn (r(2)=1.00, P<0.0001). Agricultural drainage ditches actively process nutrients and could potentially be managed to optimize this processing to minimize SP export from these landscapes.


Asunto(s)
Agricultura , Fósforo/análisis , Ríos/química , Abastecimiento de Agua/análisis , Agroquímicos/análisis , Medio Oeste de Estados Unidos , Movimientos del Agua
13.
Carbohydr Res ; 341(11): 1820-7, 2006 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-16697997

RESUMEN

Agro-industrial by-products are a potential source of added-value phenolic acids with promising applications in the food and pharmaceutical industries. Here two purified feruloyl esterases from Aspergillus niger, FAEA and FAEB were tested for their ability to release phenolic acids such as caffeic acid, p-coumaric acid and ferulic acid from coffee pulp, apple marc and wheat straw. Their hydrolysis activity was evaluated and compared with their action on maize bran and sugar beet pulp. The specificity of both enzymes against natural and synthetic substrates was evaluated; particular attention was paid to quinic esters and lignin monomers. The efficiency of both enzymes on model substrates was studied. We show the ability of these enzymes to hydrolyze quinic esters and ester linkages between phenolic acids and lignin monomer.


Asunto(s)
Agricultura/métodos , Agroquímicos/análisis , Hidrolasas de Éster Carboxílico/metabolismo , Hidroxibenzoatos/metabolismo , Residuos Industriales/análisis , Aspergillus niger/enzimología , Biodegradación Ambiental , Ácidos Cafeicos/química , Ácidos Cafeicos/metabolismo , Café/química , Ácidos Cumáricos/química , Ácidos Cumáricos/metabolismo , Proteínas Fúngicas/metabolismo , Hidrólisis , Hidroxibenzoatos/química , Isoenzimas/metabolismo , Malus/química , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Plantas Comestibles/química , Especificidad por Sustrato , Zea mays/química
15.
Vet Clin North Am Food Anim Pract ; 16(3): 455-64, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11084986

RESUMEN

Basic laboratory evaluation of water quality for livestock should include measurement of TDS, sulfate, nitrate-nitrite, and coliform bacteria. Supplementary water tests may include pH, sodium, iron, magnesium, chloride, calcium, potassium, manganese, and contaminants specific to the situation. Using the best-quality drinking water available contributes to the optimal production of livestock. Restricted quantity of drinking water or drinking water containing excessive levels of nitrate, TDS, sulfate, and other constituents can affect growth and production of all classes of animals. Drinking-water quality and availability should be evaluated as a cause of poor performance or nonspecific disease conditions in livestock. It is important that attempts to evaluate water quality include obtaining a thorough history, making astute observations, and asking intelligent questions. A thorough laboratory examination of animal specimens and water samples should be evaluated in view of existing standards for livestock drinking-water quality.


Asunto(s)
Microbiología del Agua , Abastecimiento de Agua/normas , Agroquímicos/análisis , Agroquímicos/envenenamiento , Animales , Animales Domésticos , Cianobacterias/patogenicidad , Nitratos/análisis , Nitratos/envenenamiento , Nitritos/análisis , Plaguicidas/análisis , Plaguicidas/envenenamiento , Agua/efectos adversos , Agua/análisis
16.
Food Addit Contam ; 15(5): 506-9, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9829033

RESUMEN

Potatoes, which had been treated 'in the field' with a commercial formulation of maleic hydrazide, were processed into potato crisps and jacket potato crisps on a factory production line using standard manufacturing conditions. Samples were taken at strategic points throughout the process and analysed to determine the degree of carry-through of residues. Results demonstrated that ca 56% of the maleic hydrazide residue in a potato could be carried through into the potato crisps, irrespective of which type of crisp was being manufactured. Results from a similarly constructed study investigating the fate of pesticides applied post-harvest showed that carry-through was less than 10%. This difference is explained in terms of the different modes of action of the two classes of pesticides being investigated. It is known that, as maleic hydrazide is a systemic pesticide, it will be located within the flesh of the potato tuber and is therefore likely to be protected from the various stages of the crisping process. However, the post-harvest non-systemic pesticides are applied to the exterior surface of the tuber and are therefore not likely to be protected in the same way. The results also showed that, due to the concentration effect caused by the loss of moisture during crisp manufacture, the levels of maleic hydrazide residues in crisps (on a mg/kg product basis) were approximately twice those measured in the original potatoes.


Asunto(s)
Agroquímicos/análisis , Contaminación de Alimentos/análisis , Manipulación de Alimentos , Herbicidas/análisis , Hidrazida Maleica/análisis , Solanum tuberosum , Humanos
17.
Food Addit Contam ; 15(5): 518-27, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9829035

RESUMEN

The residue levels of trichlorfon, fenthion and its metabolites were determined in olives, olive oil and vegetation water after treatment of olive trees at different times before harvest. The highest residues of fenthion were detected in oil, while the highest level of trichlorfon was found in vegetation water. The time gap between treatment and harvest strongly influences the residue levels of fenthion in olives and olive products. The levels of fenthion, which were lower than the maximum residue level (MRL) established by the Italian regulations, were obtained only when the treatment was carried out 60 days before harvest, so it may be necessary to use the insecticide trichlorfon 30 or 10 days before harvest since it leaves low residue levels in oils.


Asunto(s)
Agroquímicos/análisis , Contaminación de Alimentos/análisis , Insecticidas/análisis , Residuos de Plaguicidas/análisis , Aceites de Plantas/química , Fentión/análisis , Fentión/química , Frutas , Humanos , Insecticidas/química , Italia , Aceite de Oliva , Triclorfón/análisis , Triclorfón/química , Contaminantes Químicos del Agua/análisis
18.
Ann Occup Hyg ; 36(6): 589-99, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1471812

RESUMEN

The margin of safety is an increasingly important index relating to crop protection products. It relates the available toxicological evidence for the chemical to exposure when the material is used. Determination of potential dermal exposure is an essential element in the calculation of the margin of safety. In the early 1980s a considerable amount of work was done by the British Agrochemicals Association Limited (B.A.A.) on potential dermal exposure. Since that research was undertaken the results obtained have often been used as a model to estimate potential dermal exposure for other crop protection products. This paper presents the findings of a study of potential dermal exposure during boom spraying of an oil-seed rape crop. The conclusions of this study are two-fold. For the application technique studied, the data for mixing and loading generated in the 1980s are inappropriate for prediction of operator exposure and consequent calculation of margin of safety for a product. Also, in future exercises, exposure data should be collected during equipment washing after spraying.


Asunto(s)
Agricultura , Agroquímicos/análisis , Exposición Profesional , Piel/química , Superficie Corporal , Brassica , Monitoreo del Ambiente , Ácidos Grasos Monoinsaturados , Humanos , Aceites de Plantas , Ropa de Protección , Aceite de Brassica napus
19.
J Assoc Off Anal Chem ; 74(4): 587-91, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1917804

RESUMEN

The present paper describes results of a national survey conducted between 1982 and 1989 to determine residues of arsenic, cadmium, copper, mercury, lead, selenium, and zinc in Canadian slaughter animals. Liver and kidney tissues from cattle, swine, poultry, horses, calves, and sheep were tested. Arsenic was found in most avian and porcine samples, and their respective means of 0.36 and 0.26 micrograms/g in liver were 7 to 12 times higher than mean concentrations found in the other species. Cadmium was found in the tissues of all species; however, levels were consistently highest in equine samples with mean values of 3.09 and 27.7 micrograms/g in liver and kidney, respectively. Copper levels greater than 150 micrograms/g were found predominantly in liver from calves and sheep, with values considerably lower in the remaining species. Mercury levels were low or not detected in all species except horses. Ninety % of equine kidneys and 54% of equine livers had mercury concentrations greater than 0.01 microgram/g, with mean values of 0.18 and 0.06 microgram/g, respectively. Lead was found in tissues of all species; however, values greater than 2 micrograms/g were found only in 2 kidneys from adult cattle and 1 kidney from a horse. Selenium, tested only in cattle, was found at mean concentrations of 0.28 microgram/g in liver, and 0.92 microgram/g in kidney. Relatively high zinc levels were found in livers of horses, pigs, and calves, with respective mean concentrations of 67.3, 65.6, and 70.2 micrograms/g.


Asunto(s)
Agroquímicos/análisis , Riñón/química , Hígado/química , Metales/análisis , Animales , Arsénico/análisis , Arsénico/farmacocinética , Cadmio/análisis , Cadmio/farmacocinética , Canadá , Bovinos , Pollos , Cobre/análisis , Cobre/farmacocinética , Caballos , Riñón/metabolismo , Plomo/análisis , Plomo/farmacocinética , Hígado/metabolismo , Mercurio/análisis , Mercurio/farmacocinética , Metales/farmacocinética , Selenio/análisis , Selenio/farmacocinética , Ovinos , Porcinos , Zinc/análisis , Zinc/farmacocinética
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