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The aims of the present study were to test the accuracy of the fatty acid ratios established by the Argentinean Legislation to detect adulterations of milk fat with animal fats and to propose a regression model suitable to evaluate these adulterations. For this purpose, 70 milk fat, 10 tallow and 7 lard fat samples were collected and analyzed by gas chromatography. Data was utilized to simulate arithmetically adulterated milk fat samples at 0%, 2%, 5%, 10% and 15%, for both animal fats. The fatty acids ratios failed to distinguish adulterated milk fats containing less than 15% of tallow or lard. For each adulterant, Multiple Linear Regression (MLR) was applied, and a model was chosen and validated. For that, calibration and validation matrices were constructed employing genuine and adulterated milk fat samples. The models were able to detect adulterations of milk fat at levels greater than 10% for tallow and 5% for lard.

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Cryptosporidium is one of the microorganisms of main concern from the point of view of Public Health, being a priority problem for water treatment plants and water regulatory institutions. Due to its small size and resistance to chlorination, Cryptosporidium removal during the process of drinking water treatment is a hard task. The effectiveness of different coagulants commonly used in the process of removal of oocysts was analyzed. The technique used was the Jar Test. It was found that: 1) coagulants with the addition of polimeric coadjuvants produce over 2 logs of oocyst removal; 2) a low value in turbidity does not necessarily mean optimal parasite removal, and 3) the addition of polyelectrolites to ferric chloride diminishes variability, both in final turbidity and Cryptosporidium removal.

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Cryptosporidium es uno de los microorganismos de mayor interés desde el punto de vista de la Salud Pública y constituye un problema prioritario para las plantas y organismos reguladores de agua. Debido a su pequeño tamaño y a su resistencia a la cloración, la eliminación por el proceso de potabilización es una tarea compleja. En este trabajo se analizó la efectividad de distintos coagulantes utilizados comúnmente en tal proceso para lograr la remoción de los ooquistes. Se trabajó con la prueba de jarras (Jar Test). Se halló que: 1) Los coagulantes con agregado de polímeros coadyuvantes producen remociones de ooquistes superiores a 2 log. 2) Un valor bajo de turbiedad no asegura una remoción óptima de los parásitos. 3) La adición de polielectrolitos al cloruro férrico disminuye la variabilidad tanto en la turbiedad final como en la eliminación de Cryptosporidium.

Cryptosporidium is one of the microorganisms of main concern from the point of view of Public Health, being a priority problem for water treatment plants and water regulatory institutions. Due to its small size and resistance to chlorination, Cryptosporidium removal during the process of drinking water treatmentis a hard task. The effectiveness of different coagulants commonly used in the process of removal of oocysts was analyzed. Thetechnique used was the Jar Test. It was found that: 1) coagulants with the addition of polimeric coadjuvants produce over 2 logs of oocyst removal; 2) a low value in turbidity does not necessarily mean optimal parasite removal, and 3) the addition of polyelectrolites to ferric chloride diminishes variability, both in final turbidity and Cryptosporidium removal.

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Cryptosporidium is one of the microorganisms of main concern from the point of view of Public Health, being a priority problem for water treatment plants and water regulatory institutions. Due to its small size and resistance to chlorination, Cryptosporidium removal during the process of drinking water treatment is a hard task. The effectiveness of different coagulants commonly used in the process of removal of oocysts was analyzed. The technique used was the Jar Test. It was found that: 1) coagulants with the addition of polimeric coadjuvants produce over 2 logs of oocyst removal; 2) a low value in turbidity does not necessarily mean optimal parasite removal, and 3) the addition of polyelectrolites to ferric chloride diminishes variability, both in final turbidity and Cryptosporidium removal.

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Trabajo cuyo objetivo fue determinar el efecto de las etapas de coagulación y floculación en la eliminación de enteroparásitos en plantas de potabilización, así como comparar la acción de distintos coagulantes y polielectrolitos, utilizando la prueba de jarras. Para la operación de remoción se utilzó sulfato de aluminio, polihidroxicloruro de aluminio, y poliacrilamida, con casi igual efectividad en los resultados. Sin embargo, se alerta sobre la necesidad de optimizar las etapas de coagulación y filtración

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The aim of this work was to determine Giardia and Cryptosporidium levels in surface water used either as recreational or drinking water source, and to estimate the relationship with bacteriological and physicochemical parameters determining water quality. This study was carried out during 22 months, in Santa Fe and Santo Tomé cities (Santa Fe Province, Argentina). Cryptosporidium from 100% of the recreational samples (44-2404 oocysts/100 l) and from 92% of water sources (< 20-539 oocysts/100 l) was detected, while Giardia was found in lower concentrations and frequencies: 72% (< 20-670 cysts/100 l) and 31% (< 20-65 cysts/100 l), respectively. Statistically significant relationships were found between these parasites and organic matter, turbidity and bacteriological indicators of contamination (Escherichia coli, streptococci, Enterococcus spp, Pseudomonas aeruginosa). These relationships, however, vary according to the sampling place, the source and levels of contamination.

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The aim of this work was to determine Giardia and Cryptosporidium levels in surface water used either as recreational or drinking water source, and to estimate the relationship with bacteriological and physicochemical parameters determining water quality. This study was carried out during 22 months, in Santa Fe and Santo TomU cities (Santa Fe Province, Argentina). Cryptosporidium from 100 of the recreational samples (44-2404 oocysts/100 l) and from 92 of water sources (< 20-539 oocysts/100 l) was detected, while Giardia was found in lower concentrations and frequencies: 72 (< 20-670 cysts/100 l) and 31 (< 20-65 cysts/100 l), respectively. Statistically significant relationships were found between these parasites and organic matter, turbidity and bacteriological indicators of contamination (Escherichia coli, streptococci, Enterococcus spp, Pseudomonas aeruginosa). These relationships, however, vary according to the sampling place, the source and levels of contamination.(AU)

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The aim of this work was to determine Giardia and Cryptosporidium levels in surface water used either as recreational or drinking water source, and to estimate the relationship with bacteriological and physicochemical parameters determining water quality. This study was carried out during 22 months, in Santa Fe and Santo TomÚ cities (Santa Fe Province, Argentina). Cryptosporidium from 100 of the recreational samples (44-2404 oocysts/100 l) and from 92 of water sources (< 20-539 oocysts/100 l) was detected, while Giardia was found in lower concentrations and frequencies: 72 (< 20-670 cysts/100 l) and 31 (< 20-65 cysts/100 l), respectively. Statistically significant relationships were found between these parasites and organic matter, turbidity and bacteriological indicators of contamination (Escherichia coli, streptococci, Enterococcus spp, Pseudomonas aeruginosa). These relationships, however, vary according to the sampling place, the source and levels of contamination.

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RESUMEN

The aim of this work was to determine Giardia and Cryptosporidium levels in surface water used either as recreational or drinking water source, and to estimate the relationship with bacteriological and physicochemical parameters determining water quality. This study was carried out during 22 months, in Santa Fe and Santo Tomé cities (Santa Fe Province, Argentina). Cryptosporidium from 100

of the recreational samples (44-2404 oocysts/100 l) and from 92

of water sources (< 20-539 oocysts/100 l) was detected, while Giardia was found in lower concentrations and frequencies: 72

(< 20-670 cysts/100 l) and 31

(< 20-65 cysts/100 l), respectively. Statistically significant relationships were found between these parasites and organic matter, turbidity and bacteriological indicators of contamination (Escherichia coli, streptococci, Enterococcus spp, Pseudomonas aeruginosa). These relationships, however, vary according to the sampling place, the source and levels of contamination.