Assessment of estimated daily intakes of benzoates for average and high consumers in Korea.

A study was performed to evaluate the estimated daily intakes (EDI) of benzoates for the average and high (90th percentile) consumers by age and sex categories in Korea. The estimation of daily intakes of benzoates was based on individual dietary intake data from the National Health and Nutrition Survey in 1998 and on the determination of benzoates in eight food categories. The EDI of benzoates for average consumers of different age groups ranged from 0.009 to 0.025 mg kg(-1) bw day(-1). For high consumers, the range of EDI of benzoates was 0.195-1.878 mg kg(-1) bw day(-1). The intakes represented 0.18-0.50% of the acceptable daily intake (ADI) of benzoates for average consumers and 3.9-37.6% of the ADI for high consumers. Foods that contributed most to the daily intakes of benzoates were mixed beverages and soy sauce in Korea.     

Estimates of the theoretical maximum daily intake of phenolic antioxidants BHA, BHT and TBHQ in Brazil

The theoretical maximum daily intakes (TMDI) of the phenolic antioxidants butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tertbutyl hydroquinone (TBHQ) in Brazil were estimated using food consumption data derived from a household economic survey and a packaged goods market survey. The estimates were based on maximum levels of use of the food additives specified in national food standards. The calculated intakes of the three additives for the mean consumer were below the ADIs. Estimates of TMDI for BHA, BHT and TBHQ ranged from 0.09 to 0.15, 0.05 to 0.10 and 0.07 to 0.12mg/kg of body weight, respectively. To check if the additives are actually used at their maximum authorized levels, analytical determinations of these compounds in selected food categories were carried out using HPLC with UV detection. BHT and TBHQ concentrations in foodstuffs considered to be representive sources of these antioxidants in the diet were below the respective maximum permitted levels. BHA was not detected in any of the analysed samples. Based on the maximal approach and on the analytical data, it is unlikely that the current ADI of BHA (0.5mg/kg body weight), BHT (0.3mg/kg body weight) and TBHQ (0.7mg/kg body weight) will be exceeded in practice by the average Brazilian consumer.     

Estimated intake of benzoic and sorbic acids in Denmark

The monitoring of food additives and recent dietary surveys carried out in Denmark have earlier been used to estimate the intake of sweeteners and nitrite in relation to acceptable daily intakes. The ubiquitous use of the preservatives benzoic and sorbic acids raises the question of the magnitude of the intake of these preservatives in relation to acceptable daily intakes. This area is explored in this paper. The content of benzoic and sorbic acids in all food groups, where they are allowed, was monitored in Denmark 17 times between 2001 and 2006 with a total of 1526 samples. Transgressions of maximum limits, illegal use or declaration faults were found in about 3% of samples. From repeated investigations on fat-based foods (salads and dressings), marmalade and stewed fruit, it is concluded that the amounts used in industry have been relatively stable throughout the whole period, although limited data for marmalade show some variation. Most foods in the categories soft drinks, dressings, fat-based salads, pickled herrings, and marmalade contain benzoic and sorbic acid, and sliced bread also contains in some cases sorbic acid. The median daily intake and intake distribution of benzoic and sorbic acids were calculated with data from the Danish National Survey of Dietary Habits and Physical Activity (age from 4 to 75 years) conducted in 2000–2004 with 5785 participants. The median intakes of both benzoic acid and sorbic acid are well below the acceptable daily intakes of 0–5 and 0–25 mg kg^?1 body weight (bw) day^?1 for benzoic and sorbic acid, respectively. However, the 90th percentile based on the average of the samples with a content of benzoic acid is higher than the acceptable daily intake for both men and women, with the highest value of 16 mg kg^?1 bw day^?1 for both boys and girls in the 4–6-year-old age group. Based on the average of all samples, the 95th percentile is over the acceptable daily intake for men up to 34 years and for women up to 24 years, and the 90th percentile for men up to 18 years and for women up to 10 years. Soft drinks, salads and dressings are the main contributors to benzoic acid intake. The sorbic acid intake based on the average of all samples is well below the acceptable daily intake. However, for the intake based on the average of samples with content, the 95th percentile exceeds the acceptable daily intake. This is caused by the dominating contribution to the intake of sorbic acid from sliced bread, but since only seven out of 42 samples have added sorbic acid, the calculation based on the average of samples with content will exaggerate the intake. With a built-in safety factor of 100 in the acceptable daily intakes and judging from the literature, the high intakes of benzoic acid should not cause any concern for ill-effects. However, there must be a reason to reconsider the maximum limits especially for benzoic acid in soft drinks, dressings and salads and for sorbic acid in sliced bread.     

Estimation of inorganic food additive (nitrite,nitrate and sulfur dioxide), antioxidant (BHA and BHT), processing agent (propylene glycol) and sweetener (sodium saccharin) concentrations in foods and their daily intake based on official inspection results in Japan in fiscal year 1998

The mean concentration and daily intake of inorganic food additives (nitrite, nitrate, and sulfur dioxide), antioxidants (BHA and BHT), a processing agent (propylene glycol), and a sweetener (sodium saccharin) were estimated based on the results of an analysis of 34,489 food samples obtained in official inspections by 106 local governments in Japan in fiscal year 1998. The ratios of mean concentrations of these seven food additives to each allowable limit were 20.0%, 53.9%, 15.5%, 6.2%, 0.4%, 18.5%, and 5.7%, respectively. The daily intakes of these food additives estimated from their concentrations in foods and the daily consumption of foods were 0.205, 0.532, 4.31, 0.119, 0.109, 77.5, and 7.27 mg per person, respectively. These amounts were 6.8%, 0.3%, 12.3%, 0.5%, 0.7%, 6.2%, and 2.6% of the acceptable daily intake (ADI), respectively, when body weight was assumed to be 50 kg. No remarkable differences in the daily intakes of these seven food additives or the ratios to the ADI were observed compared with the results based on the official inspections in fiscal years 1994 and 1996.     

Caffeine daily intake from dietary sources in Brazil

A survey on the potential intake of caffeine was carried out in Campinas, SP, Brazil, in the summer of 1993. The survey was based on a representative sample of 600 individuals, 9-80 years old, who were asked about their habitual usage of coffee, tea, chocolate products and carbonated beverages. Caffeine levels in the products were determined by high performance liquid chromatography with a UV-visible detector at 254 nm. Individual daily intakes (mg/kg b.w.) of caffeine were calculated from the consumption data generated by the survey and the caffeine content of the analysed products. Of all those interviewed, 81% consumed soft drinks regularly, 75% coffee, 65% chocolate products and 37% tea. Of the analysed products, coffee showed the highest amount of caffeine. The average and median potential daily intake of caffeine by the studied population were, respectively, 2.74 and 1.85mg/kg b.w. Coffee, tea, chocolate products and carbonated beverages accounted for median individual daily intakes of 1.90, 0.32, 0.19, and 0.19mg/kg b.w., respectively. These data show that coffee is the most important vehicle for caffeine intake within the studied population.     

Dietary intake of four artificial sweeteners by Irish pre-school children

In spite of rigorous pre- and post-market reviews of safety, there remains a high level of debate regarding the use of artificial sweeteners in foods. Young children are of particular interest when assessing food chemical exposure as a result of their unique food consumption patterns and comparatively higher exposure to food chemicals on a body weight basis when compared with the general population. The present study examined the intakes of four intense sweeteners (acesulfame K, aspartame, saccharin, sucralose) in the diets of children aged 1–4 years using food consumption and sweetener presence data from the Irish National Pre-school Nutrition Survey (2010–11) and analytical data for sweetener concentration in foods obtained from a national testing programme. Four exposure assessment scenarios were conducted using the available data on sweetener occurrence and concentration. The results demonstrated that the mean daily intakes for all four sweeteners were below the acceptable daily intake (ADI) (17–31%), even considering the most conservative assumptions regarding sweetener presence and concentration. High consumer intakes (P95) were also below the ADI for the four sweeteners when more realistic estimates of exposure were considered. Both sweetener occurrence and concentration data had a considerable effect on reducing the estimated intake values, with a combined reduction in intakes of 95% when expressed as a proportion of the ADI. Flavoured drinks were deemed to be a key contributor to artificial sweetener intakes in this population cohort. It was concluded that there is no health risk to Irish pre-school children at current dietary intake levels of the sweeteners studied.     

Estimated intake of the sweeteners,acesulfame-K and aspartame,from soft drinks,soft drinks based on mineral waters and nectars for a group of Portuguese teenage students

In a survey of levels of acesulfame-K and aspartame in soft drinks and in light nectars, the intake of these intense sweeteners was estimated for a group of teenage students. Acesulfame-K was detected in 72% of the soft drinks, with a mean concentration of 72 mg l^?1 and aspartame was found in 92% of the samples with a mean concentration of 89 mg l^?1. When data on the content of these sweeteners in soft drinks were analysed according to flavour, cola drinks had the highest mean levels for both sweeteners with 98 and 103 mg l^?1 for acesulfame-K and aspartame, respectively. For soft drinks based on mineral water, aspartame was found in 62% of the samples, with a mean concentration of 82 mg l^?1 and acesulfame-K was found in 77%, with a mean level of 48 mg l^?1. All samples of nectars contained acesulfame-K, with a mean concentration of 128 mg l^?1 and aspartame was detected in 80% of the samples with a mean concentration of 73 mg l^?1. A frequency questionnaire, designed to identify adolescents having high consumption of these drinks, was completed by a randomly selected sample of teenagers (n = 65) living in the city of Coimbra, in 2007. The estimated daily intakes (EDI) of acesulfame-K and aspartame for the average consumer were below the acceptable daily intakes (ADIs). For acesulfame-K, the EDI was 0.7 mg kg^?1 bw day^?1 for soft drinks, 0.2 mg kg^?1 bw day^?1 for soft drinks based on mineral waters, and 0.5 mg kg^?1 bw day^?1 for nectars, representing 8.0%, 2.2%, and 5.8% of the ADI, respectively. A similar situation was observed for aspartame. In this way, the EDI for soft drinks was 1.1 mg kg^?1 day^?1, representing only 2.9% of the ADI. In respect of nectars, the EDI was 0.2 mg kg^?1 bw day^?1, representing 0.5% of the ADI. Soft drinks based on mineral waters showed the lowest EDI values of 0.3 mg kg^?1 bw day^?1, accounting for 0.7% of the ADI.     

Assessment of the exposure to Allura Red colour from the consumption of red juice-based and red soft drinks in Italy

This article reports the results of a survey and an exposure study, based on a probabilistic approach, concerning red juice-based and red soft drink products in Italy. It highlights the fact that the estimates of both the consumption rates and colorant intakes are related to the hypotheses of scenarios. In fact, the study estimates that, on average, consumers of red soft drinks consume 53.1 L year(-1), ranging from 39.1 to 70.7 L of soft drink products under one scenario, or 21.3 L, and from 12.7 and 35.9 L under another hypothesis; while 9.5 L of red juice-based drinks are consumed per year, ranging from 7.0 to 12.5 L, under one scenario, or on average 6.9 L, and ranging from 3.2 to 17.7 L under another scenario. The amount of colorant in a red beverage ranged from 10.9 mg l(-1) in a red soft drink up to 55.9 mg l(-1) in a red juice-based product. The risk evaluation process showed that in all cases the intake of E129 was always lower than the acceptable daily intake. The exposure assessment showed high average intakes of Allura Red in the worst-case scenario, on average, 6.5 and 13.9 mg day(-1), up to 25.0 and 33.0 mg day(-1) at the 95th percentile, for juice-based and soft drinks respectively. The most realistic scenario estimated a weighted average daily intake of Allura Red, on average from about 0.3 to 0.5 mg day(-1) at the 95th percentile, and from 0.4 to 0.6 mg day(-1) for the 95th percentile, from juice-based and soft drinks, respectively. Actually, the highest colorant intake was estimated in a 'health' juice-based drink. The intake of E129 significantly increased with a high level of colorant (>40 mg l(-1)).     

Estimate of intake of benzoic acid in the Belgian adult population

An exposure assessment was performed to estimate average daily benzoic acid intake for Belgian adults. Food consumption data were retrieved from the national food-consumption survey. As a first step, individual food-consumption data were multiplied with the maximum permitted use levels for benzoic acid per food group (Tier 2). As a second step, a label survey to identify the foods where benzoic acid is effectively used as an additive and a literature review of the possible occurrence of benzoic acid as a natural substance were performed. With this information, a refined list of foods was drafted for the quantification of benzoic acid, which was performed by a high-performance liquid chromatography (HPLC) method, optimized and validated for this purpose. Individual food-consumption data were then multiplied with the actual average concentrations of benzoic acid per food group (Tier 3). Usual intakes were calculated using the Nusser method. The mean benzoic acid intake was 1.58 mg kg^?1 body weight day^?1 (Tier 2) and 1.25 mg kg^?1 body weight day^?1 (Tier 3). In Tier 2, men exceeded the acceptable daily intake (ADI) of 5 mg kg^?1 body weight day^?1 at the 99th percentile. The greatest contributors to the benzoic acid intake were soft drinks. Benzoic acid as a natural substance represents only a small percentage of the total intake. The results show that actual benzoic acid intake is very likely to be below the ADI. However, there is a need to collect national food-consumption data for children as they might be more vulnerable to an excessive intake.     

Estimation of preservative concentrations in foods and their daily intake based on official inspection results in Japan in fiscal year 1998

The mean concentration and daily intake of five preservatives were estimated based on the results of an analysis of 89,927 samples of food obtained in official inspections by Japanese local governments in fiscal year 1998. The mean concentration of benzoic acid was 9.5% of the allowable limit, and those of dehydroacetic acid, p-hydroxybenzoic acid, propionic acid, and sorbic acid were 1.5%, 5.7%, 1.7%, and 23.9%, respectively. Daily intake levels of these preservatives per person estimated from the concentration and daily consumption of foods were 6.23 mg, 0.0303 mg, 1.02 mg, 8.10 mg, and 25.0 mg, respectively, and assuming a body weight of 50 kg, the amounts of benzoic acid, p-hydroxybenzoic acid, and sorbic acid consumed were 2.5%, 0.2%, and 2.0% of their acceptable daily intakes, respectively. These values were similar to those obtained based on the results of the official inspections in fiscal years 1994 and 1996.     

Exposure assessment of food preservatives (sulphites, benzoic and sorbic acid) in Austria

An exposure assessment was performed to estimate the potential intake of preservatives in the Austrian population. Food consumption data of different population groups, such as preschool children aged 3-6 years, female and male adults aged 19-65 years were used for calculation. Levels of the preservatives in food were derived from analyses conducted from January 2007 to August 2010. Dietary intakes of the preservatives were estimated and compared to the respective acceptable daily intakes (ADIs). In the average-intake scenario, assuming that consumers randomly consume food products that do or do not contain food additives, estimated dietary intakes of all studied preservatives are well below the ADI for all population groups. Sulphite exposure accounted for 34%, 84% and 89% of the ADI in preschool children, females and males, respectively. The mean estimated daily intake of benzoic acid was 32% (preschool children), 31% (males) and 36% (females) of the ADI. Sorbic acid intakes correspond to 7% of the ADI in preschool children and 6% of the ADI in adults. In the high-intake scenario assuming that consumers always consume food products that contain additives and considering a kind of brand loyalty of consumers, the ADI is exceeded for sulphites among adults (119 and 124%, respectively). Major contributors to the total intake of sulphites were wine and dried fruits for adults. Mean estimated dietary intakes of benzoic acid exceeded the ADI in all population groups, 135% in preschool children, 124% in females and 118% of the ADI in males, respectively. Dietary intakes of sorbic acid are well below the ADI, accounting for a maximum of 30% of the ADI in preschool children. The highest contributors to benzoic and sorbic acid exposure were fish and fish products mainly caused by high consumption data of this large food group, including also mayonnaise-containing fish salads. Other important sources of sorbic acid were bread, buns and toast bread and fruit and vegetable juices.     

Exposure assessment of food preservatives (sulphites,benzoic and sorbic acid) in Austria

An exposure assessment was performed to estimate the potential intake of preservatives in the Austrian population. Food consumption data of different population groups, such as preschool children aged 3–6 years, female and male adults aged 19–65 years were used for calculation. Levels of the preservatives in food were derived from analyses conducted from January 2007 to August 2010. Dietary intakes of the preservatives were estimated and compared to the respective acceptable daily intakes (ADIs). In the average-intake scenario, assuming that consumers randomly consume food products that do or do not contain food additives, estimated dietary intakes of all studied preservatives are well below the ADI for all population groups. Sulphite exposure accounted for 34%, 84% and 89% of the ADI in preschool children, females and males, respectively. The mean estimated daily intake of benzoic acid was 32% (preschool children), 31% (males) and 36% (females) of the ADI. Sorbic acid intakes correspond to 7% of the ADI in preschool children and 6% of the ADI in adults. In the high-intake scenario assuming that consumers always consume food products that contain additives and considering a kind of brand loyalty of consumers, the ADI is exceeded for sulphites among adults (119 and 124%, respectively). Major contributors to the total intake of sulphites were wine and dried fruits for adults. Mean estimated dietary intakes of benzoic acid exceeded the ADI in all population groups, 135% in preschool children, 124% in females and 118% of the ADI in males, respectively. Dietary intakes of sorbic acid are well below the ADI, accounting for a maximum of 30% of the ADI in preschool children. The highest contributors to benzoic and sorbic acid exposure were fish and fish products mainly caused by high consumption data of this large food group, including also mayonnaise-containing fish salads. Other important sources of sorbic acid were bread, buns and toast bread and fruit and vegetable juices.     

US Food and Drug Administration's Total Diet Study: intake of nutritional and toxic elements, 1991-96

The Food and Drug Administration (FDA) has conducted the Total Diet Study (TDS) annually since 1961. The TDS is designed to monitor the US food supply for levels of toxic chemical contaminants (pesticide residues, industrial chemicals and toxic elements) and nutritional elements. Foods are generally collected four times a year, once from each of four regions of the country. The foods are prepared table-ready before being analysed. From the results of the TDS, dietary intakes of these analytes are estimated for selected age- sex groups in the US population. This paper reports on the dietary intake of 10 nutritional and four toxic elements based on measurements made in foods collected in the TDS between 1991 and late 1996. Average daily intakes were estimated for 14 age-sex groups in the US population, as well as the contribution of specific food groups to total intakes. For most nutritional elements, teenage boys and adult males had the highest daily intakes. Intakes by infants were below the intake references for seven of 10 nutritional elements, and young girls and women had inadequate intakes of at least half the nutritional elements. Intakes by children between 2 and 10 years of age, teenage boys, and adult males met or exceeded the reference intakes for the majority of nutritional elements. Intakes by all population groups were well below the reference intakes for all toxic elements.     

Total diet studies: the identification of core foods in the United States food supply.

Some total diet studies are based on the selection and analysis of core foods in a national or regional food supply. One way to select core foods is by computerized evaluation of the daily food intakes reported by subjects participating in national food consumption surveys. The foods consumed by the population groups of concern may be aggregated into core food groups. The foods within each group may be ranked according to daily intake and weight percentage of the total diet. The food that best represents each group may then be identified as a core food, and the daily consumption levels for each food group may then be assigned to the core food representing the group. Consumption levels may be determined for the specific age-sex categories of concern. To assess the representativeness of core foods identified in this manner, the food composition database of the national survey may be used to determine nutrient intakes based on the full range of foods in the database versus nutrient intakes based on the core foods.     

用Budget方法评估食品防腐剂摄入量

分析了在Codex为了设定食品添加剂的使用标准而被应用的Budget 方法论,并提出了适用于中国人饮食情况的使用准则.在此基础上对苯甲酸及其钠盐、山梨酸及其钾盐、对羟基苯甲酸乙脂和双乙酸钠的国内理论最大摄入量进行了估算.其结果苯甲酸及其钠盐、对羟基苯甲酸乙脂、双乙酸钠的每日最大理论摄入量超过了ADI(acceptable daily intakes)值,而山梨酸及其钾盐的每日最大理论摄入量估算值低于ADI值,因此即使在允许使用的所有食品群里以目前使用标准使用山梨酸及其钾盐也不会造成危害.     

Dietary intakes of six intense sweeteners by Irish adults

This research investigated the intakes of six intense sweeteners: acesulfame-K (E950), aspartame (E951), cyclamate (E952), saccharin (E954), sucralose (E955), and steviol glycosides (E960) in the diets of Irish adults, using data from the National Adult Nutrition Survey. A food label survey that included products currently available on the Irish market supplemented the analysis. Sweetener intakes were investigated using three different exposure scenarios; beginning with a crude assessment which assumed that all foods permitted to contain the additives of interest always did contain them, and at their maximum permitted level (Tier 1). Refined assessments estimated intakes of the six sweeteners using food consumption data up to brand level with additive occurrence data from a survey of products currently available on the Irish market (Tier 2) and sweetener concentration data (Tier 3). Results of all exposure assessment scenarios demonstrate that intakes of each of the sweeteners of interest by the total population were below the relevant ADI level (mg kg^?1 bodyweight^?1), even by high consumers (P99). The three sweeteners consumed in highest amounts were acesulfame-k, aspartame, and sucralose. The main sources of these sweeteners in the diet were ‘cider and perry’, ‘energy reduced and no added sugar (ER and NAS) carbonated flavoured drinks’, ‘table-top sweeteners’, ‘dairy products’, ‘solid food supplements’, and ‘sauces’. Intakes of the six intense sweeteners are currently not a concern among Irish adults. However, exposure to these chemicals should be monitored on a regular basis due to evolving market and consumption patterns.     

Nitrate, nitrite, and N-nitroso compounds in Finnish foods and the estimation of the dietary intakes

An estimate of the dietary intakes of nitrite, nitrate and N-nitroso compounds is presented, based on the analytical data supplied by the Finnish Food Quality Control. Figures on the food consumption of the Finnish population, taken from a national dietary survey, and food consumption of 1768 children and adolescents over a 48-h recall period were used. The mean daily dietary nitrate intakes were estimated to be about 55 mg for the total population and for children and adolescents. The mean nitrite intakes were 1.88 mg for the total population and 1.07 mg for children and adolescents. The intake of N-nitroso compounds (NDMA) was estimated to be 0.08 micrograms for the total population and 0.02 micrograms for children. Nitrates were found to originate mainly from vegetables (80%), nitrites from meat products (97%) and nitrosamines mostly from fish products and beer. A comparison of the estimate of dietary intake of with ADI values indicated that the nitrite intake of the total population was 23% and by children 39% of ADI. The average weight was approximately 60 kg for adults and 20 kg for children. When measured average weight (39 kg) was used, and the nitrite intake was found to be 28% of ADI. Nitrate intakes from food additives were 2.5% and 1.4% of the ADI value, respectively. When the total nitrate intake from various food sources was compared with the ADI (which is given only for food additives), the estimated nitrate intake of the total population was 25% and that of children 28% of the ADI value.     

The effect of food dry matter intake on the flow of amino acids at the terminal ileum for rats fed an enzyme‐hydrolysed casein‐based diet

The aim of the study was to determine whether food dry matter intake had an effect on endogenous ileal amino acid flows in the rat when the flows were expressed in units of mg g^?1 dry matter. Eighty 200 g body weight rats were trained for 7 days to consume a casein‐based diet over a daily 3 h feeding period, and then an enzyme‐hydrolysed casein (MW < 5000 Da)‐based diet, with chromic oxide as an indigestible marker, was fed for a further 8 days. The mean ratio of food intake to metabolic body weight over all 80 rats was determined on days 11 and 12. On day 15, food was offered to groups of 10 rats at each of eight intake levels. The intake levels were calculated from the mean food intake value and individual metabolic body weights and scaled in increments of 0.1 by factors ranging from 0.3 to 1.0. Digesta were collected from the terminal ileum 3 h after the start of the meal, and endogenous ileal amino acid flows were determined after amino acid and Cr analyses of the diet and endogenous ileal digesta fractions prepared by centrifugation and ultrafiltration (10 000 Da molecular weight cut‐off). The linear regression relationships between ileal amino acid flows, expressed as mg g^?1 dry matter, and dry matter intakes demonstrated that all slopes were negative but that the slopes for nine of these amino acids were not significantly different from zero (P > 0.05). There were significant slopes (P < 0.05) for the other eight amino acids, although the magnitudes of the effect were small. When the data were re‐examined after removing the lowest feeding level, the slopes for most of these amino acids were no longer statistically significant. The results showed that the measures of amino acid flow (mg g^?1 dry matter), except for isoleucine and cystine, over a wide range of food intakes were not materially affected by food intake. From the perspective of bioassay logistics the results indicate that expressing ileal amino acid flows proportional to dry matter intake is justified over the range of intakes found in practice for determining true ileal amino acid digestibility by the enzyme‐hydrolysed casein method. © 2002 Society of Chemical Industry     

Effect of dosing regime on intake estimation using the n‐alkane technique in sheep fed pelleted grass meal

An experiment was carried out to evaluate the n‐alkane technique for estimating the voluntary intake of pelleted grass meal by sheep. Two groups of 12 Scottish Blackface sheep were dosed once daily or twice daily with paper pellets containing 130 mg of C₃₂ alkane. Mean daily intakes over a 5 day period were estimated from n‐alkane concentrations in faeces and compared with actual intakes measured by weighing of food. Two faecal sampling frequencies were compared (once or twice daily) at each dosing frequency. Diurnal patterns of intake were determined by weighing food residues every 3 h for 4 days. Diurnal patterns of faecal n‐alkane concentration were determined from rectal grab samples collected every 3 h for 2 days. There was no effect of dosing frequency on actual intake. Estimated intake was higher for twice‐daily than once‐daily dosed animals when twice‐daily faecal sampling was employed (P < 0.05), although differences between mean actual and estimated intakes were not significant. The accuracy of estimation of individual intakes was better for sheep dosed once daily, at both faecal sampling frequencies, than for sheep dosed twice daily. This may have been due to diurnal variation in food intake and digesta outflow from the rumen, demonstrating the importance of matching n‐alkane dosing and sampling regimes to the digesta kinetics of the diet fed. © 2000 Society of Chemical Industry     

N-methyl carbamate concentrations and dietary intake estimates for apple and grape juices available on the retail market in Canada.

Infants and young children consume fruit juices and drinks at rates exceeding those of older children and adults. Carbamate pesticides are known to be used on a broad spectrum of crops, including orchard and vine crops such as apples and grapes. Concern over potential exposure to these acutely toxic pesticides by infants and young children has increased in the last decade. Liquid chromatography with fluorescence detection was used to determine the concentrations of seven N-methyl carbamates and three transformation products in domestic and imported apple and grape juices collected across Canada. Carbaryl was the most frequently (58.6%) detected N-methyl carbamate in juice samples studied. It was observed more frequently in grape juices than in apple or mixed juices. Oxamyl and methomyl were detected in apple juice samples, although they were below detection limits in all grape and mixed juice samples analysed. Maximum levels of carbaryl, methomyl and oxamyl were 93, 6.7 and 4.6 ng ml(-1), respectively. All other analytes were not present in any juice sample at concentrations above the method detection limit (0.3 ng ml(-1)). In all cases, N-methyl carbamate residues were well below the maximum residue limit established for apples and grapes in the Canadian Food and Drug Regulations. No estimated dietary intakes were above the acceptable daily intakes in any age-sex category, where an acceptable daily intake has been proposed. Carbaryl short-term intake estimates were calculated and all were below the proposed acute reference doses.