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Relationship between arsenic content of food and water applied for food processing Texto completo
2013
Sugár, Éva | Tatár, Enikő | Záray, Gyula | Mihucz, Victor G.
As part of a survey conducted by the Central Agricultural Office of Hungary, 67 food samples including beverages were taken from 57 food industrial and catering companies, 75% of them being small and medium-sized enterprises (SMEs). Moreover, 40% of the SMEs were micro entities. Water used for food processing was simultaneously sampled. The arsenic (As) content of solid food stuff was determined by hydride generation atomic absorption spectrometry after dry ashing. Food stuff with high water content and water samples were analyzed by inductively coupled plasma mass spectrometry. The As concentration exceeded 10μg/L in 74% of the water samples taken from SMEs. The As concentrations of samples with high water content and water used were linearly correlated. Estimated As intake from combined exposure to drinking water and food of the population was on average 40% of the daily lower limit of WHO on the benchmark dose for a 0.5% increased incidence of lung cancer (BMDL0.5) for As. Five settlements had higher As intake than the BMDL0.5. Three of these settlements are situated in Csongrád county and the distance between them is less than 55km. The maximum As intake might be 3.8μg/kg body weight.
Mostrar más [+] Menos [-]Perchlorate as an emerging contaminant in soil, water and food Texto completo
2016
Kumarathilaka, Prasanna | Oze, Christopher | Indraratne, S.P. | Vithanage, Meththika
Perchlorate (ClO4−) is a strong oxidizer and has gained significant attention due to its reactivity, occurrence, and persistence in surface water, groundwater, soil and food. Stable isotope techniques (i.e., (18O/16O and 17O/16O) and 37Cl/35Cl) facilitate the differentiation of naturally occurring perchlorate from anthropogenic perchlorate. At high enough concentrations, perchlorate can inhibit proper function of the thyroid gland. Dietary reference dose (RfD) for perchlorate exposure from both food and water is set at 0.7 μg kg−1 body weight/day which translates to a drinking water level of 24.5 μg L−1. Chromatographic techniques (i.e., ion chromatography and liquid chromatography mass spectrometry) can be successfully used to detect trace level of perchlorate in environmental samples. Perchlorate can be effectively removed by wide variety of remediation techniques such as bio-reduction, chemical reduction, adsorption, membrane filtration, ion exchange and electro-reduction. Bio-reduction is appropriate for large scale treatment plants whereas ion exchange is suitable for removing trace level of perchlorate in aqueous medium. The environmental occurrence of perchlorate, toxicity, analytical techniques, removal technologies are presented.
Mostrar más [+] Menos [-]Natural food evaluation and water quality in zero water exchange culture of Litopenaeus vannamei fertilized with wheat bran Texto completo
2009
Campos, Susmara Silva | Silva, Ugo Lima | Lúcio, Maria Zita Tabosa | Correia, Eudes de Souza
The aim of this study was to analyze the influence of organic fertilizer on the availability of natural food (plankton and benthos) and water quality. Two fertilization protocols were adopted using inorganic and organic fertilizers with shrimp (stocked treatment) and their controls (unstocked treatment). Experimental units consisted of 12 circular fiberglass tanks (500 l) with estuarine sediment, individual aeration and no water exchange. In stocked treatments were used 40 juveniles/m², and they were fed with 35% crude protein marine shrimp ration, three times a day. Under the organic fertilization protocol, the plankton showed higher abundance of Nitzschia and rotifers, the phytobenthos consisted mainly of Nitzschia, Amphiprora and Oscillatoria, the epibenthos was represented mainly by nematodes and rotifers, and the macro-invertebrates were mainly oligochaetes. In relation to inorganic fertilization, the plankton was represented mainly by Coscinodiscus and rotifers, the phytobenthos consisted mainly of Amphiprora and Oscillatoria, the epibenthos was represented mainly by nematodes and rotifers, and the macro-invertebrates were mainly oligochaetes. Dissolved oxygen was higher for organic fertilizer (6.16 ± 0.98 mg/l) than for inorganic (5.92 ± 1.19 mg/l) while the other water quality parameters did not present significant differences. Survival was similar in the two fertilization regimes (96.6%). Final body weight was 11.89 ± 1.73 g for the inorganic fertilizers and 12.28 ± 1.71 g for organic fertilizer. It is concluded that wheat bran showed good performance in the water quality without exchange, in the availability of natural food, and in the growth and survival of the shrimps in the microcosms.
Mostrar más [+] Menos [-]Response of broilers to deprivation of food and water for 24 hours
1995
Knowles, T.G. | Warriss, P.D. | Brown, S.N. | Edwards, J.E. | Mitchell, M.A.
In order to provide information on the state of hydration of broilers during marketing, 7-week-old Ross broilers of mixed sex were kept at 17 or 23 degrees C and deprived of food, or food and water, for 24 h. Measurements were made of live weight, carcass weight, muscle moisture, packed cell volume, plasma glucose, corticosterone, total protein, osmolality and sodium. There was a decrease in live weight, carcass weight, plasma glucose and plasma total protein, and an increase in packed cell volume and corticosterone, in birds deprived of food, or food and water. Muscle moisture increased in birds deprived of food and decreased in birds deprived of food and water. Osmolality decreased in birds deprived of food, the decrease being greater in birds at 23 degrees C. Plasma sodium levels were higher in birds kept at 23 degrees C and increased only in birds deprived of food and water at 23 degrees C.
Mostrar más [+] Menos [-]Immediate pre-meal water ingestion decreases voluntary food intake in lean young males Texto completo
2016
Corney, Robert A. | Sunderland, Caroline | James, Lewis J.
PURPOSE: Consuming 375–500 ml of water 30 min before a meal has been shown to reduce energy intake in older, but not younger adults. This study investigated the effects of ingesting a water preload immediately pre-meal (<1 min before eating) on within-meal ad libitum energy intake in non-obese young males. METHODS: Fourteen healthy males [mean (SD) age 27 (3) years, height 1.83 (0.05) m, body weight 80.47 (9.89) kg, body fat 17.5 (4.0) %, body mass index 24.0 (2.5) kg/m²] completed a familiarisation trial and two experimental trials in randomised counterbalanced order. Subjects arrived at the laboratory overnight fasted and consumed an ad libitum porridge breakfast. Immediately prior to the meal, subjects consumed either a 568 ml (1 pint) water preload (preload trial) or no preload (control trial). Visual analogue scale questionnaires to assess hunger, fullness and satisfaction were completed before and after the meal in both trials, as well as after the water preload. RESULTS: Ad libitum energy intake was greater (P < 0.001) during control [2551 (562) kJ] than preload [1967 (454) kJ]. Ad libitum water intake was also greater (P < 0.001) during control [318 (226–975) ml] than preload [116 (0–581) ml]. The water preload increased fullness and satisfaction and decreased hunger compared to pre-trial (P < 0.001) and the control trial (P < 0.001). CONCLUSION: This study demonstrates that consumption of a 568 ml water preload immediately before a meal reduces energy intake in non-obese young males. This might therefore be an effective strategy to suppress energy intake in this population and possibly assist with weight management.
Mostrar más [+] Menos [-]Use of agar-based diet to fulfil the food and water requirements of mice Texto completo
1984
Lang, J. A. | Lang, C. M. | White, W. J.
Mice were fed an agar-based diet without an additional source of water for 5 weeks. In comparison with a similar group of mice fed a commercial diet and water ad libitum, there were no significant changes in bodyweight.
Mostrar más [+] Menos [-]Separating food and water deprivation in locusts: effects on the patterns of consumption, locomotion and growth Texto completo
1996
Raubenheimer, D. | Gade, G.
In a factorial experiment, fifth-instar Locusta migratoria (L.) (Orthoptera: Acrididae) were given either dry food (lyophilized grass) and drinking water, food only, water only, or neither food nor water. Food consumption and insect weight were measured daily, and the behaviour of each locust was recorded for 5 h on each of four consecutive days and for 2.5 h on the fifth. Consumption declined progressively in locusts given food only, and those given water only were not observed to drink after the first day of food deprivation. The decline in food consumption on the first day was accounted for by a decrease in the average duration of feeds, which remained constant thereafter. The further decline in consumption over subsequent days was due to a progressive decline in the number of feeds. Although food availability did not slow weight loss relative to locusts given neither food nor water, the availability of water without food did. The proportion of time locomoting increased in all deprivation treatments, but the pattern of change across the five observation days differed markedly between treatments. Locusts given food but no water increased locomotion from 20% of the time budget (the value for controls) to 30% on the first day of deprivation, and by the second day had reached a plateau of approximately 65%, which was maintained until the experiment was terminated on day 5. In contrast, locusts given water but no food approached the 65% level of locomotion on the first day, which was statistically greater than the 55% observed in those deprived of both food and water. This increase was due both to an increase in the number of locomotion bouts initiated and an increase in the average duration of locomotion bouts. On the second and third days, all deprivation treatments maintained locomotion at around 65%. By day 4, locomotion had decreased to approximately 15% in locusts deprived of both food and water, but not in those deprived of food only or water only. Unlike those given only food, locusts given only water showed a reduction in locomotion of c. 15% on the fifth day.
Mostrar más [+] Menos [-]Food shortage affects flight migration of the giant water bug Lethocerus deyrolli in the prewintering season Texto completo
2005
Ōba, Shin'ya | Takagi, Hideharu
The endangered giant water bug Lethocerus deyrolli (Vuillefroy) is frequently attracted in large numbers to artificial lights in Japan. To examine factors enhancing flight migration for L. deyrolli, we carried out field work in western Hyogo Prefecture, central Japan, in September during the nonreproductive and prewintering season. The body weight of specimens collected under flight migration (flight bugs) was significantly less than that of those collected in ponds (pond bugs). A field experiment using open cages in a rice paddy field was carried out with two treatments, with and without a food supply. The remaining rate of L. deyrolli for the food present treatment was significantly higher than that for the food absent treatment for the first two days. These results suggest that L. deyrolli would fly in search of food when the food supply of the present habitat becomes unsuitable.
Mostrar más [+] Menos [-]Fresh produce and their soils accumulate cyanotoxins from irrigation water: Implications for public health and food security Texto completo
2017
Lee, Seungjun | Jiang, Xuewen | Manubolu, Manjunath | Riedl, Ken | Ludsin, Stuart A. | Martin, Jay F. | Lee, JiYoung
Microcystin (MC), a hepatotoxin that can adversely affect human health, has become more prevalent in freshwater ecosystems worldwide, owing to an increase in toxic cyanobacteria blooms. While consumption of water and fish are well-documented exposure pathways of MCs to humans, less is known about the potential transfer to humans through consumption of vegetables that have been irrigated with MC-contaminated water. Likewise, the impact of MC on the performance of food crops is understudied. To help fill these information gaps, we conducted a controlled laboratory experiment in which we exposed lettuce, carrots, and green beans to environmentally relevant concentrations of MC-LR (0, 1, 5, and 10μg/L) via two irrigation methods (drip and spray). We used ELISA and LC-MS/MS to quantify MC-LR concentrations and in different parts of the plant (edible vs. inedible fractions), measured plant performance (e.g., size, mass, edible leaves, color), and calculated human exposure risk based on accumulation patterns. MC-LR accumulation was positively dose-dependent, with it being greater in the plants (2.2–209.2μg/kg) than in soil (0–19.4μg/kg). MC-LR accumulation varied among vegetable types, between plant parts, and between irrigation methods. MC-LR accumulation led to reduced crop growth and quality, with MC-LR persisting in the soil after harvest. Observed toxin accumulation patterns in edible fractions of plants also led to estimates of daily MC-LR intake that exceeded both the chronic reference dose (0.003μg/kg of body weight) and total daily intake guidelines (0.04μg/kg of body weight). Because the use of MC-contaminated water is common in many parts of the world, our collective findings highlight the need for guidelines concerning the use of MC-contaminated water in irrigation, as well as consumption of these crops.
Mostrar más [+] Menos [-]Drinking water boosts food intake rate, body mass increase and fat accumulation in migratory blackcaps (Sylvia atricapilla) Texto completo
2008
Tsurim, Ido | Sapir, Nir | Belmaker, Jonathan | Shanni, Itai | Izhaki, Ido | Wojciechowski, Michał S. | Karasov, William H. | Pinshow, Berry
Fat accumulation by blackcaps (Sylvia atricapilla) is a prerequisite for successful migratory flight in the autumn and has recently been determined to be constrained by availability of drinking water. Birds staging in a fruit-rich Pistacia atlantica plantation that had access to water increased their body mass and fat reserves both faster and to a greater extent than birds deprived of water. We conducted a series of laboratory experiments on birds captured during the autumn migration period in which we tested the hypotheses that drinking water increases food use by easing limitations on the birds' dietary choices and, consequently, feeding and food processing rates, and that the availability of drinking water leads to improved digestion and, therefore, to higher apparent metabolizable energy. Blackcaps were trapped in autumn in the Northern Negev Desert, Israel and transferred to individual cages in the laboratory. Birds were provided with P. atlantica fruit and mealworms, and had either free access to water (controls) or were water-deprived. In experiment 1, in which mealworm availability was restricted, water-deprived birds had a fourfold lower fruit and energy intake rates and, consequently, gained less fat and total mass than control birds. Water availability did not affect food metabolizability. In experiment 2, in which mealworms were provided ad libitum, water availability influenced the birds' diet: water-restricted birds ate more mealworms, while control birds consumed mainly P. atlantica fruit. Further, in experiment 2, fat and mass gain did not differ between the two treatment groups. We conclude that water availability may have important consequences for fat accumulation in migrating birds while they fatten at stopover sites, especially when water-rich food is scarce. Restricted water availability may also impede the blackcap's dietary shift from insectivory to frugivory, a shift probably necessary for successful pre-migratory fattening.
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