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The discharge of untreated or partially treated wastewater can have detrimental impacts on the quality of water bodies, posing a significant threat to public health and the environment. In Ecuador, previous research indicates a high prevalence of antimicrobial resistant (AMR) bacteria in surface waters affected by human activities, including irrigation channels. In this study, we analyzed sediment samples collected from an irrigation channel utilized for agricultural purposes in northern Ecuador, using microbiological techniques and whole-genome sequencing (WGS). Our investigation revealed the first documented occurrence of E. kobei in Ecuador and the initial report of environmental E. kobei ST2070. Furthermore, we identified the coexistence of OXA-10-type class D ß-lactamase and KPC-2-type class A ß-lactamase in the E. kobei isolate (UTA41), representing the first report of such a phenomenon in this species. Additionally, we detected various antibiotic resistance genes in the E. kobei UTA41 isolate, including blaCTX-M-12, fosA, aac(6')-lb, sul2, msr(E), and mph(A), as well as virulence genes such as bacterial efflux pump and siderophore biosynthesis genes. We also identified two intact prophage regions (Entero_186 and Klebsi_phiKO2) in the isolate. Our study presents the first evidence of E. kobei isolate containing two carbapenemase-encoding genes in environmental samples from Latin America. This finding indicates the potential spread of critical-priority bacteria in water samples originating from anthropogenic sources, such as urban wastewater discharges and livestock facilities.

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It has been established that climate change has a direct impact on water availability, an essential resource for agricultural development. As a result, controlling, mitigating, and adapting to water deficit requires the advancement of research on promising wild flora species. As recent studies have shown, wild relatives of certain cultivars are tolerant to adverse factors, enabling the development of sustainable and resilient agriculture. The present study evaluated the morpho-physiology and productivity of tomato scions grafted on wild Solanaceae (Datura stramonium, Solanum sisymbriifolium, Solanum quitoense, and Cyphomandra betacea) grown under water deficit conditions (100% ETc - high level, 75% ETc - moderate level, 50% ETc - medium level, and 25% ETc - low level). The results showed that tomato plants grafted on Datura stramonium rootstocks performed better morpho-physiologically under deficit irrigation. The improved osmoregulation caused by a higher relative water content (98.49%) allowed the scion to be more tolerant to water stress. In addition, these scions showed high water potential during their phenological stages (vegetative -0.47 MPa, flowering -0.59 MPa, and production -0.64 MPa), as well as improved photosynthetic efficiency. The overall tolerance of the scion resulted in better yield (8.14 kg/plant) with higher number of commercially valuable fruits. The D. stramonium rootstock allowed better management and use of irrigation water, increasing productivity (54.95 kg/m3); that is, it is presented as a species with potential for establishing tomato production areas in scenarios of water scarcity or cultivation under deficit irrigation.

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Contaminated irrigation water is among many potential vehicles of human pathogens to food plants, constituting significant public health risks especially for the fresh produce category. This review discusses some available guidelines or regulations for microbiological safety of irrigation water, and provides a summary of some common methods used for characterizing microbial contamination. The goal of such exploration is to understand some of the considerations that influence formulation of water testing guidelines, describe priority microbial parameters particularly with respect to food safety risks, and attempt to determine what methods are most suitable for their screening. Furthermore, the review discusses factors that influence the potential for microbiologically polluted irrigation water to pose substantial risks of pathogenic contamination to produce items. Some of these factors include type of water source exploited, irrigation methods, other agro ecosystem features/practices, as well as pathogen traits such as die-off rates. Additionally, the review examines factors such as food safety knowledge, other farmer attitudes or inclinations, level of social exposure and financial circumstances that influence adherence to water testing guidelines and other safe water application practices. A thorough understanding of relevant risk metrics for the application and management of irrigation water is necessary for the development of water testing criteria. To determine sampling and analytical approach for water testing, factors such as agricultural practices (which differ among farms and regionally), as well as environmental factors that modulate how water quality may affect the microbiological safety of produce should be considered. Research and technological advancements that can improve testing approach and the determination of target levels for hazard characterization or description for the many different pollution contexts as well as farmer adherence to testing requirements, are desirable.

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[This corrects the article DOI: 10.3389/fmicb.2021.709418.].

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AIMS: To gather data on agricultural practices in organic farms in Sao Paulo, Brazil, and evaluate their relationship with the microbiological characteristics of samples collected along the production chain. METHODS AND RESULTS: Practices data were based on field observations and interviews with farmers in 10 selected organic lettuce producing farms. Counts of Enterobacteriaceae and surveys for Salmonella were performed in samples of lettuce (before and after washing), fertilizers, irrigation and washing water, all collected in the same farm. Water samples were also tested for total coliforms and generic Escherichia coli. Isolated Enterobacteriaceae were identified by MALDI-TOF MS. Contamination of lettuce was influenced by some agricultural practices: chicken manure-based fertilization resulted in higher Enterobacteriaceae counts in lettuce when compared to other types of manure, whereas pre-washed lettuces presented lower microbial counts than non-pre-washed samples. Salmonella was detected in one lettuce sample by qPCR. Escherichia coli was detected in all irrigation water samples. All sample types contained Enterobacteriaceae species commonly reported as opportunistic human pathogens. CONCLUSIONS: The data highlight the need for improvement in the good agricultural practices in the studied farms. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides information on agricultural practices and microbiological characteristics of organic lettuce, contributing to the development of more accurate risk assessments.

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In cities across the globe, the majority of wastewater - that includes drug resistant and pathogenic bacteria among other contaminants - is released into streams untreated. This water is often subsequently used for irrigation of pastures and produce. This use of wastewater-contaminated streams allows antibiotic-resistant bacteria to potentially cycle back to humans through agricultural products. In this study, we investigated the prevalence of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli isolated from produce and irrigation water across 17 provinces of Ecuador. A total of 117 vegetable samples, 119 fruit samples, and 38 irrigation water samples were analyzed. Results showed that 11% of the samples were positive for E. coli including 11 irrigation water samples (29%), and samples of 13 vegetables (11%), and 11 fruits (9%). Among the 165 E. coli isolates cultured, 96 (58%) had the ESBL phenotype, and 58% of ESBL producing E. coli came from irrigation water samples, 11% from vegetables, and 30% from fruits. The bla CTX-M - 55, bla CTX-M 65, and bla CTX-M 15 genes were the most frequently found gene associated with the ESBL phenotype and coincided with the bla CTX-M alleles associated with human infections in Ecuador. Three isolates had the mcr-1 gene which is responsible for colistin resistance. This report provides evidence of the potential role of irrigation water in the growing antimicrobial resistance crisis in Ecuador.

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Metals in the environment have been an increasing research topic over the past decade, since they can be found in both natural and drinking water, including irrigation of crops and edible plants with contaminated water. The aim of this study was to investigate the uptake of Cr by arugula (Eruca sativa) in a greenhouse experiment, simulating the open field irrigation conditions. We also evaluate the toxic effects of Cr on oxidative stress by measuring the antioxidant capacity and polyphenol profile in the plant. The study examines the irrigation of arugula, during 15 and 21 days, with four Cr (VI) concentrations, ranging from 0 (control) to 250 µg. L-1. Arugula plants were able to accumulate Cr when irrigated during 15 and 21 days in all the Cr concentrations evaluated. The estimated daily intake (EDI) shows that the amount of Cr accumulated by arugula plants does not represent a threat to human health. Application of Cr levels induced some changes in content, profile and capacity of antioxidants depending on Cr concentration and time of exposure. Taking into account that E. sativa is consumed due to its polyphenol-related health benefits, the allowable Cr limits in irrigation water should be reviewed, in order to maximize health benefits associated with its consumption, and also to improve vegetable quality. Arugula is a valuable and nutritious food, that should not be excluded from a balanced diet. Chromium concentration in irrigation water as well as the speciation forms present in vegetables should be controlled.

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Forage palm (Cactaceae) is considered an important resource in the semiarid region of Brazil. This study aimed to analyze the effect of different levels of salinity in irrigation water on the growth of three forage palm cultivars. The study was conducted at the Federal University of Campina Grande (7° 12' 52.6" S; 35° 54' 22.3" W) in 120 L pots open to the sky. The experiment was a complete randomized block, with four replications and a 4 × 3 factorial arrangement. The treatments consisted of four levels of salinity in irrigation water with electrical conductivity of 0.2, 2.0, 3.8, and 5.6 dS m–¹, and three forage palm cultivars: Miúda or Doce (Nopalea cochenillifera Salm Dyck), Orelha de Elefante (Opuntia stricta), and Baiana or IPA–Sertânia (Nopalea cochenillifera Salm Dyck). At 150 days after treatments, it was evaluated: length, width and perimeter of primary and secondary cladodes and total number of cladodes. Variance analysis was performed using an F-test (p < 0.05); significant effects were subjected to quadratic regression analysis for the quantitative variable, and the Tukey test (p < 0.05) for the qualitative variable. Salinity levels in irrigation water did not affect the growth variables. There was a significant difference in the growth of forage palm as a function of its cultivar. The Baiana cultivar showed the highest vegetative growth of length and perimeter of primary and secondary cladodes, while Miúda and Orelha de Elefante presented the greatest cladode numbers for plant and cladode widths, respectively.(AU)

A palma forrageira é considerada um importante recurso forrageiro no Semiárido brasileiro. Assim, objetivou-se avaliar o efeito de diferentes níveis de salinidade da água de irrigação no crescimento de três cultivares de palma forrageira. O estudo foi realizado na Universidade Federal de Campina Grande (7°12'52,56' S; 35°54'22,26" O) em vasos de 120 L dispostos a céu aberto. O delineamento experimental foi em blocos casualizados em esquema fatorial 4 × 3, com 4 repetições. Os tratamentos consistiram de 4 níveis de salinidade da água de irrigação com condutividades elétricas de: 0,2; 2,0; 3,8 e 5,6 dS m-¹; e três cultivares de palma forrageira: Miúda ou Doce (Nopalea cochenillifera Salm Dyck), Orelha de Elefante (Opuntia stricta), Baiana ou IPA Sertânia (Nopalea cochenillifera Salm Dyck). Aos 150 dias após o início dos tratamentos, avaliou-se: comprimento, largura e perímetro de cladódios primários e secundários e número de cladódios totais. As variáveis foram submetidas à análise de variância pelo teste F (p < 0,05) e quando houve efeito significativo foi realizada análise de regressão linear e quadrática para a variável quantitativa e o teste de Tukey (p < 0,05), para a variável qualitativa. Os níveis de salinidade da água de irrigação não exerceram influência sobre as variáveis de crescimento. Existe diferença significativa no crescimento da palma forrageira em função de sua cultivar. A cultivar Baiana apresenta crescimento vegetativo superior para comprimento e perímetro de cladódio primário e secundário, enquanto que as cultivares Miúda e Orelha de Elefante são superiores para número de cladódios por planta e largura de cladódio, respectivamente.(AU)

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Forage palm (Cactaceae) is considered an important resource in the semiarid region of Brazil. This study aimed to analyze the effect of different levels of salinity in irrigation water on the growth of three forage palm cultivars. The study was conducted at the Federal University of Campina Grande (7° 12' 52.6" S; 35° 54' 22.3" W) in 120 L pots open to the sky. The experiment was a complete randomized block, with four replications and a 4 × 3 factorial arrangement. The treatments consisted of four levels of salinity in irrigation water with electrical conductivity of 0.2, 2.0, 3.8, and 5.6 dS m–¹, and three forage palm cultivars: Miúda or Doce (Nopalea cochenillifera Salm Dyck), Orelha de Elefante (Opuntia stricta), and Baiana or IPA–Sertânia (Nopalea cochenillifera Salm Dyck). At 150 days after treatments, it was evaluated: length, width and perimeter of primary and secondary cladodes and total number of cladodes. Variance analysis was performed using an F-test (p < 0.05); significant effects were subjected to quadratic regression analysis for the quantitative variable, and the Tukey test (p < 0.05) for the qualitative variable. Salinity levels in irrigation water did not affect the growth variables. There was a significant difference in the growth of forage palm as a function of its cultivar. The Baiana cultivar showed the highest vegetative growth of length and perimeter of primary and secondary cladodes, while Miúda and Orelha de Elefante presented the greatest cladode numbers for plant and cladode widths, respectively.

A palma forrageira é considerada um importante recurso forrageiro no Semiárido brasileiro. Assim, objetivou-se avaliar o efeito de diferentes níveis de salinidade da água de irrigação no crescimento de três cultivares de palma forrageira. O estudo foi realizado na Universidade Federal de Campina Grande (7°12'52,56' S; 35°54'22,26" O) em vasos de 120 L dispostos a céu aberto. O delineamento experimental foi em blocos casualizados em esquema fatorial 4 × 3, com 4 repetições. Os tratamentos consistiram de 4 níveis de salinidade da água de irrigação com condutividades elétricas de: 0,2; 2,0; 3,8 e 5,6 dS m-¹; e três cultivares de palma forrageira: Miúda ou Doce (Nopalea cochenillifera Salm Dyck), Orelha de Elefante (Opuntia stricta), Baiana ou IPA Sertânia (Nopalea cochenillifera Salm Dyck). Aos 150 dias após o início dos tratamentos, avaliou-se: comprimento, largura e perímetro de cladódios primários e secundários e número de cladódios totais. As variáveis foram submetidas à análise de variância pelo teste F (p < 0,05) e quando houve efeito significativo foi realizada análise de regressão linear e quadrática para a variável quantitativa e o teste de Tukey (p < 0,05), para a variável qualitativa. Os níveis de salinidade da água de irrigação não exerceram influência sobre as variáveis de crescimento. Existe diferença significativa no crescimento da palma forrageira em função de sua cultivar. A cultivar Baiana apresenta crescimento vegetativo superior para comprimento e perímetro de cladódio primário e secundário, enquanto que as cultivares Miúda e Orelha de Elefante são superiores para número de cladódios por planta e largura de cladódio, respectivamente.

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A solid-phase microextraction (SPME) coupled to gas chromatography-mass spectrometry method was validated for the simultaneous determination of penconazole, cyproconazole, epoxiconazole, deltamethrin, azoxystrobin and kresoxim-methyl in paddy rice irrigation water. Different SPME fiber coatings and pH values were tested. Polydimethylsiloxane (PDMS) and pH 7 were chosen to optimize extraction. All pesticides presented a recovery percentage between 90.5 and 104.2%; and detection and quantification limits were 0.03 and 0.05 µg/kg for azoxystrobin and cyproconazole, 0.02 and 0.05 µg/kg for deltametrhin and epoxiconazole, 0.02 and 0.03 µg/kg for kresoxim-methyl, and 0.01 and 0.02 µg/kg for penconazole. The expanded uncertainty was estimated for all pesticides showing results lower than 20%. A total of 100 paddy rice irrigation water samples, collected in different rice fields from Argentina, were evaluated. The study showed that 86 of them presented residues. The concentrations exceeded the values that were set by European legislation and the frequencies were higher than 86% so the agricultural practices should be revised.

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More than 500 unreclaimed mines and associated waste sites exist on the Navajo Nation reservation as a result of uranium (U) mining from the 1940s through the 1980s. For this study, the impact of U-mine waste on a common, locally grown crop food was examined. The goal of this site-specific study was to determine metal(loid) concentration levels of arsenic (As), cadmium (Cd), cesium (Cs), molybdenum (Mo), lead (Pb), thorium (Th), U, vanadium (V) and selenium (Se) in Cucurbita pepo Linnaeus (squash), irrigation water, and soil using inductively coupled plasma-mass spectrometry. The concentrations of metal(loid)s were greatest in roots > leaves > edible fruit (p < 0.05), respectively. There were significant differences between metal(loid)s in squash crop plot usage (<5 years versus >30 years) for V (p = 0.001), As (p < 0.001), U (p = 0.002), Cs (p = 0.012), Th (p = 0.040), Mo (p = 0.047), and Cd (p = 0.042). Lead and Cd crop irrigation water concentrations exceeded the United States Environmental Protection Agency (USEPA) Maximum Contaminant Levels for drinking water for those metals. Edible squash concentration levels were 0.116 mg/kg of As, 0.248 mg/kg of Pb, 0.020 mg/kg of Cd, and 0.006 mg/kg of U. Calculated human ingestion of edible squash did not exceed Provisional Tolerable Weekly Intake or Tolerable Upper Limit levels from intake based solely on squash consumption. There does not appear to be a food-ingestion risk from metal(loid)s solely from consumption of squash. Safer access and emphasis on consuming regulated water was highlighted. Food intake recommendations were provided. Continued monitoring, surveillance, and further research are recommended.

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Resumen Objetivo. Identificar microorganismos fitopatógenos presentes en las aguas utilizadas para riego en la cuenca media del rio Bogotá. Métodos. Las muestras fueron tomadas en doce fincas de la cuenca media y analizadas con la técnica de filtración por membrana. Las bacterias se identificaron por bioquímica y los hongos por claves dicotomas. Resultados. El agua de riego analizada contenía bacterias como: E.coli, P. vulgaris, A. urinae, E. cloacae, B.cereus, S. marcescens, B. brevis, y en cuanto a los hongos se encontraron: Aspergillus fumigatus, Aspergillus flavus., Mucor sp., Rhizopus sp., Penicillium sp. y Fusarium sp. La presencia de estos potenciales fitopatógenos en el agua indican un alto riesgo de contaminación y dispersión de éstos en los cultivos.

Abstract Objective. Identify phytopathogenic microorganisms present in the water used for irrigation in the middle basin of the river Bogota. Methods. Samples were taken at 12 farms of the middle basin and analyzed by the membrane filtration technique. The bacteria were identified by biochemical and fungi by dichotomies keys. Results. The irrigation water contained bacteria analyzed as E. coli, P. vulgaris, A. urinae, E. cloacae, B. cereus, S. marcescens, B. brevis, and as for the mushrooms found: A. fumigatus, A. flavus, Mucor sp., Rhizopus sp., Penicillium sp. and Fusarium sp. The presence of these potential pathogens in water indicate a high risk of contamination and dispersion thereof in crops.

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Foodborne illness resulting from the consumption of contaminated fresh produce is a common phenomenon and has severe effects on human health together with severe economic and social impacts. The implications of foodborne diseases associated with fresh produce have urged research into the numerous ways and mechanisms through which pathogens may gain access to produce, thereby compromising microbiological safety. This review provides a background on the various sources and pathways through which pathogenic bacteria contaminate fresh produce; the survival and proliferation of pathogens on fresh produce while growing and potential methods to reduce microbial contamination before harvest. Some of the established bacterial contamination sources include contaminated manure, irrigation water, soil, livestock/ wildlife, and numerous factors influence the incidence, fate, transport, survival and proliferation of pathogens in the wide variety of sources where they are found. Once pathogenic bacteria have been introduced into the growing environment, they can colonize and persist on fresh produce using a variety of mechanisms. Overall, microbiological hazards are significant; therefore, ways to reduce sources of contamination and a deeper understanding of pathogen survival and growth on fresh produce in the field are required to reduce risk to human health and the associated economic consequences.

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Abstract The water resources mismanagement is a common concern in the agriculture, and this issue is boosting salinity processes in the Colombian lands. Thus, this paper aimed to assess the soil salinity risk in the RUT irrigation district for sugarcane, grape, and passion fruit by coupling SOSALRIEGO-GIS. First, sources of surface water and their influence areas were identified in the RUT irrigation district. Afterwards, inputs (water ionic constituents, electrical conductivity of rainwater, annual rainfall, crop salt tolerance, soil texture, and leaching fraction) fed in the SOSALRIEGO model, and then, the leaching requirement (LR) of each zone was computed (output) for each crop. Finally, employing GIS, LR values were arranged in categories in order to map the soil salinity risk in the RUT irrigation district for each crop and zone. The soil salinity risk fell into a medium rank for sugarcane, medium to high ranks for grape, and high to very high ranks for passion fruit. Furthermore, the soil salinity risk was higher in zones with poor irrigation water quality. Zones II and III, which canals convey domestic wastewater and drained water fell in greater salinity risk category than zone I, which bears water withdrawal from the Cauca River.

Resumen La inadecuada gestión de los recursos hídricos es una preocupación común en la agricultura, y este hecho está impulsando procesos de salinización en los suelos de Colombia. Por lo tanto, este trabajo tuvo como objetivo evaluar el riesgo de salinización del suelo en el distrito de riego RUT para cultivos de caña de azúcar, uva, maracuyá integrando el modelo SOSALRIEGO con SIG. En primer lugar, se identificaron las fuentes hídricas y sus áreas de influencia. Posteriormente, los parámetros de entrada (composición iónica del agua, conductividad eléctrica del agua de lluvia, precipitación anual, tolerancia de cultivos a la salinidad, cultivos, textura del suelo y la eficiencia de lavado) alimentaron el modelo SOSALRIEGO y, a continuación, el Requerimiento de Lavado de sales (RL) fue calculado para cada cultivo. Por último, utilizando SIG, los valores RL se organizaron en categorías con el fin de mapear el riesgo de salinización del suelo en el distrito de riego RUT para cada cultivo en cada zona. El riesgo de salinización se clasificó como medio para caña de azúcar, medio a Alto para la uva, y alto a muy alto para maracuyá. Además, el riesgo salinización del suelo encontrado fue mayor en zonas con baja calidad del agua de riego. Las Zonas II y III, en las cuales los canales conducen aguas residuales domésticas y el agua drenada fueron calificados en categorías superiores de riesgo de salinización que la Zona I, la cual recibe agua extraída directamente del río Cauca.

Resumo A inadequada gestão dos recursos hídricos é uma preocupação comum na agricultura, este fato está impulsando processos de salinização nos solos da Colômbia. Portanto, esta pesquisa objetivou avaliar o risco da salinização dos solos no distrito de irrigação RUT às culturas de cana-de-açúcar, uva e maracujá; integrando o modelo SOSALRIEGO com os Sistemas de Informações Geográficas (SIG). Em primeiro lugar, os parâmetros de entrada (composição iônica da água de irrigação, condutividade elétrica da água de precipitação, precipitação anual, tolerância das culturas à salinidade, culturas, textura do solo e eficiência de lavado de sais) alimentaram o modelo SOSALRIEGO e, seguidamente o requerimento de lavado de sais (RL) foi calculado. Finalmente, usando os SIG, os valores de RL foram categorizados com o objetivo de mapear o risco de salinização dos solos na área de estudo para cada cultura em cada zona. O risco de salinização foi classificado como Médio para a cultura da cana-de-açúcar, Médio a Elevado para a cultura da uva, e Elevado a Muito Elevado para o maracujá. Além disso, o risco de salinização foi maior nas zonas com menor qualidade da água de irrigação. As zonas II e III, cujos canais conduzem águas residuais e de drenagem foram qualificados em categorias maiores de risco do que a zona I, a qual extrai a água diretamente do Rio Cauca.

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Investigation of major viruses responsible for acute viral gastroenteritis, such as norovirus (NoV), rotavirus species A (RVA) and human adenovirus (HAdV), was conducted in the mountainous region of the state of Rio de Janeiro in a lettuce-producing area. Irrigation water and lettuce samples were collected at different production stages. Viruses were concentrated using an adsorption-elution method and detected by quantitative polymerase chain reaction (qPCR). We detected HAdV in all collection points, although no virus infectivity was shown. The RVA was the most prevalent virus from both water (16.7% [10/60]) and lettuce samples (11.1% [4/36]), with loads ranging from 2.97 × 102 to 6.88 × 103 genomic copies per litre (gc L-1) and 6.24 × 102 to 1.30 × 104 gc per 25 g, respectively. NoV was detected in 8.33% [8/96] in water and lettuce samples, with concentrations ranging from 7.29 × 101 to 1.92 × 103 gc L-1 and from 4.29 × 101 to 2.98 × 103 gc 25 g-1, respectively. Escherichia coli values also demonstrated poor quality of the irrigation and washing water. The presence of at least two different virus strains in all sites reveals the need to improve basic sanitation measures in order to increase food safety.

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Irrigation water has been recognized as an important microbial risk factor for fruits and vegetables in many production areas, but there is still a lack of information about how the microbiological quality of different irrigation water sources and climatic conditions influence the safety of vegetables produced in Brazil. This study evaluated the distribution of generic E. coli and the prevalence of E. coli O157:H7 in two different water sources (ponds and streams bordering farmlands and urban areas) used for irrigation and on commercially produced lettuces in Southern Brazil. We also evaluated the effect of agricultural factors and meteorological conditions in the potential contamination of water and produce samples. A longitudinal study was conducted on four farms during a year (July 2014 to August 2015). The results showed generic E. coli prevalence of 84.8% and 38.3% in irrigation water samples and on lettuces, respectively, indicating irrigation water as an important source of contamination of lettuces. No significant differences were detected in the counts of E. coli between the two different surface water sources. The climatic conditions, particularly rainfall and environmental temperature, have influenced the high concentration of E. coli. The highest loads of E. coli in irrigation water and on lettuces were found during the warmest time of the year. E. coli O157:H7 was detected by qualitative polymerase chain reaction (qPCR) in 13 water samples but only 4 were confirmed by isolation in culture media.

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The aims of this study were to evaluate the contamination of lettuce (Lactuca sativa), produced in Londrina, Paraná (PR), with total coliform, coliform at 45 °C, E. coli, and Salmonella spp.; and to determine the E. coli contamination of irrigation water used at the farms studied. Four farms were evaluated, of which three produced lettuce using a conventional system and one using an organic system. An evaluation of the production practices of the farms was also carried out. A total of 111 samples were analyzed, 71 lettuce samples from the conventional system and 40 samples from the organic system. A total of eight irrigation water samples were collected for analysis. Coliform at 45 °C counts above the limit tolerated by Brazilian legislation were observed in 2.8% (2/71) of conventionally grown lettuce samples, and Salmonella spp. was isolated in 1.4% (1/71) of those samples. In the organic lettuce samples, 12.5% (5/40) had coliform at 45 °C counts above the limit tolerated and Salmonella spp. was not detected. Irrigation water samples from three farms were unsatisfactory, with counts higher than 102 MPN of E. coli per 100mL. The results of this study demonstrate that most conventionally grown lettuce samples show good sanitary conditions in production, and that lettuce contamination is not related to contamination found in irrigation water samples. The results also showed that the organic production practices required by Brazilian certification agencies should be applied to ensure that contamination of produced lettuce remains controlled.(AU)

Os objetivos deste estudo foram avaliar a contaminação por coliformes totais, coliformes a 45 °C, Escherichia coli e Salmonella spp. em alfaces crespas (Lactuca sativa) produzidas na região de Londrina, PR, e a contaminação por E. coli das amostras da água de irrigação empregadas nas propriedades estudadas. Quatro propriedades rurais foram avaliadas, das quais três produziam alfaces pelo sistema convencional e uma pelo sistema orgânico. Avaliação das práticas de produção dessas propriedades também foi realizada. Um total de 111 amostras foi coletado, sendo 71 amostras de produção convencional e 40 amostras de produção orgânica. Oito amostras de água de irrigação foram coletadas para análise. Contagens de coliformes a 45 °C acima do tolerado pela legislação brasileira foram observadas em 2,8 % (2/71) das alfaces convencionais analisadas, e Salmonella spp. foi isolada em 1,4 % (1/71) destas amostras. Quanto às amostras orgânicas, 12,5 % (5/40) apresentaram contagens de coliformes a 45 °C acima do limite preconizado e Salmonella spp. não foi isolada nessas amostras. As amostras de água de irrigação de três propriedades rurais apresentaram resultados insatisfatórios com contagens superiores a 102 MPN de E. coli por 100 mL. Os resultados obtidos neste estudo mostraram que a maioria das amostras de alfaces convencionais analisadas apresentou boas condições higiênicosanitárias e uma não relação com a contaminação encontrada nas amostras de água de irrigação. Os resultados também mostraram que as práticas de produção orgânica exigidas pelas certificadoras devem ser aplicadas para que a contaminação destes alimentos permaneça sob controle.(AU)

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RESUMO

Salmonella enterica (S. enterica) is the main cause of foodborne diseases in the Chilean population. With the aim of characterizing the presence of S. enterica in bodies of water, samples from 40 sources were obtained, including rivers and irrigation canals used by agricultural farms in the most populated regions of Chile. As result, 35 S. enterica isolates belonging to several serotypes were detected, with the highest frequency represented by Typhimurium and Enteritidis. All strains showed phenotypic antimicrobial resistance, and most of them were multiresistant to critically important antimicrobials. In addition, the pulse-field gel electrophoresis analysis using XbaI and BlnI endonucleases showed that seven Salmonella isolates belonging to serotypes Typhimurium, Enteritidis and Infantis had identical pulsotypes to outbreak-associated clinical isolates detected in the Chilean population, suggesting a public health risk of water pollution in this region. Among sampling sites, the higher detection rates were observed in rural than urban and peri-urban areas, suggesting that the animal husbandry might contribute for environmental dispersion of this pathogen. Future efforts should address the characterization of cause-and-effect relationship between water contamination and foodborne disease, including the implementation of surveillance programmes to tackle potential risks for both human and animal populations.

Assuntos

RESUMO

The aims of this study were to evaluate the contamination of lettuce (Lactuca sativa), produced in Londrina, Paraná (PR), with total coliform, coliform at 45 °C, E. coli, and Salmonella spp.; and to determine the E. coli contamination of irrigation water used at the farms studied. Four farms were evaluated, of which three produced lettuce using a conventional system and one using an organic system. An evaluation of the production practices of the farms was also carried out. A total of 111 samples were analyzed, 71 lettuce samples from the conventional system and 40 samples from the organic system. A total of eight irrigation water samples were collected for analysis. Coliform at 45 °C counts above the limit tolerated by Brazilian legislation were observed in 2.8% (2/71) of conventionally grown lettuce samples, and Salmonella spp. was isolated in 1.4% (1/71) of those samples. In the organic lettuce samples, 12.5% (5/40) had coliform at 45 °C counts above the limit tolerated and Salmonella spp. was not detected. Irrigation water samples from three farms were unsatisfactory, with counts higher than 102 MPN of E. coli per 100mL. The results of this study demonstrate that most conventionally grown lettuce samples show good sanitary conditions in production, and that lettuce contamination is not related to contamination found in irrigation water samples. The results also showed that the organic production practices required by Brazilian certification agencies should be applied to ensure that contamination of produced lettuce remains controlled.

Os objetivos deste estudo foram avaliar a contaminação por coliformes totais, coliformes a 45 °C, Escherichia coli e Salmonella spp. em alfaces crespas (Lactuca sativa) produzidas na região de Londrina, PR, e a contaminação por E. coli das amostras da água de irrigação empregadas nas propriedades estudadas. Quatro propriedades rurais foram avaliadas, das quais três produziam alfaces pelo sistema convencional e uma pelo sistema orgânico. Avaliação das práticas de produção dessas propriedades também foi realizada. Um total de 111 amostras foi coletado, sendo 71 amostras de produção convencional e 40 amostras de produção orgânica. Oito amostras de água de irrigação foram coletadas para análise. Contagens de coliformes a 45 °C acima do tolerado pela legislação brasileira foram observadas em 2,8 % (2/71) das alfaces convencionais analisadas, e Salmonella spp. foi isolada em 1,4 % (1/71) destas amostras. Quanto às amostras orgânicas, 12,5 % (5/40) apresentaram contagens de coliformes a 45 °C acima do limite preconizado e Salmonella spp. não foi isolada nessas amostras. As amostras de água de irrigação de três propriedades rurais apresentaram resultados insatisfatórios com contagens superiores a 102 MPN de E. coli por 100 mL. Os resultados obtidos neste estudo mostraram que a maioria das amostras de alfaces convencionais analisadas apresentou boas condições higiênicosanitárias e uma não relação com a contaminação encontrada nas amostras de água de irrigação. Os resultados também mostraram que as práticas de produção orgânica exigidas pelas certificadoras devem ser aplicadas para que a contaminação destes alimentos permaneça sob controle.

Assuntos

RESUMO

The aims of this study were to evaluate the contamination of lettuce (Lactuca sativa), produced in Londrina, Paraná (PR), with total coliform, coliform at 45 C, E. coli, and Salmonella spp.; and to determine the E. coli contamination of irrigation water used at the farms studied. Four farms were evaluated, of which three produced lettuce using a conventional system and one using an organic system. An evaluation of the production practices of the farms was also carried out. A total of 111 samples were analyzed, 71 lettuce samples from the conventional system and 40 samples from the organic system. A total of eight irrigation water samples were collected for analysis. Coliform at 45 C counts above the limit tolerated by Brazilian legislation were observed in 2.8% (2/71) of conventionally grown lettuce samples, and Salmonella spp. was isolated in 1.4% (1/71) of those samples. In the organic lettuce samples, 12.5% (5/40) had coliform at 45 C counts above the limit tolerated and Salmonella spp. was not detected. Irrigation water samples from three farms were unsatisfactory, with counts higher than 102MPN of E. coli per 100mL. The results of this study demonstrate that most conventionally grown lettuce samples show good sanitary conditions in production, and that lettuce contamination is not related to contamination found in irrigation water samples. The results also showed that t

Os objetivos deste estudo foram avaliar a contaminação por coliformes totais, coliformes a 45 C, Escherichia coli e Salmonella spp. em alfaces crespas (Lactuca sativa) produzidas na região de Londrina, PR, e a contaminação por E. coli das amostras da água de irrigação empregadas nas propriedades estudadas. Quatro propriedades rurais foram avaliadas, das quais três produziam alfaces pelo sistema convencional e uma pelo sistema orgânico. Avaliação das práticas de produção dessas propriedades também foi realizada. Um total de 111 amostras foi coletado, sendo 71 amostras de produção convencional e 40 amostras de produção orgânica. Oito amostras de água de irrigação foram coletadas para análise. Contagens de coliformes a 45 C acima do tolerado pela legislação brasileira foram observadas em 2,8 % (2/71) das alfaces convencionais analisadas, e Salmonella spp. foi isolada em 1,4 % (1/71) destas amostras. Quanto às amostras orgânicas, 12,5 % (5/40) apresentaram contagens de coliformes a 45 C acima do limite preconizado e Salmonella spp. não foi isolada nessas amostras. As amostras de água de irrigação de três propriedades rurais apresentaram resultados insatisfatórios com contagens superiores a 102MPN de E. coli por 100 mL. Os resultados obtidos neste estudo mostraram que a maioria das amostras de alfaces convencionais analisadas apresentou boas condições higiênico-sanitárias e uma n