4-Nonylphenol (NP) and bisphenol A (BPA) are phenolic substances used in high volumes by the industry. Studies on cells and in experimental animals have shown that both these compounds can be classified as estrogenic hormone disrupters. Information about the exposure of humans to NP and BPA is still scarce, especially regarding levels in human blood. The first aim of this study was to investigate possible sources of NP and BPA exposure from food, by analyzing the levels of NP and BPA from a Swedish food market basket, based on the Swedish per capita food consumption. A second aim was to investigate blood serum levels of NP and BPA, as well as NP-ethoxylates, among young women in Sweden (n=100). Moreover, associations between food consumption and blood NP and BPA levels were studied. In food, NP was to some extent found at levels above limit of quantification (LOQ 20 ng/g fresh weight) in fruits, cereal products, vegetables, and potatoes. BPA levels above LOQ (2 ng/g fresh weight) were found in fish, meats, potatoes, and dairy products. The estimated mean intakes per capita were (medium bound) 27 µg NP/day and 3.9 µg BPA/day, showing that food is a source of BPA and NP in the general Swedish population. In blood serum, free NP above limit of detection (LOD 0.5 ng/g) was detected in 46% of the study participants while detectable levels of total NP (LOD 0.8 ng/g) were observed in 43%. The corresponding percentages for BPA were 25% and 22%, respectively. The results indicate that there is a continuous source of exposure to NP and BPA that is high enough for free NP and BPA to be detected in some consumers. Among the participants with quantifiable levels of free and total NP (n=38), 85% (median, range: 38-112%) of the NP was present as free NP. For BPA 76% (49-109%) was detected as free BPA (n=15). All women had levels of ethoxylates of NP below LOD (0.1-0.7 ng/g). A significantly higher total consumption of fruits and vegetables was reported in questionnaires by participants with NP levels at or above LOD than among women with levels below LOD. This result is supporting the market basket results of relatively high NP levels in these types of food.
More than one-third of the calories consumed by U.S. and European populations contain acrylamide, a substance classified as a "probable human carcinogen" based on laboratory data. Thus, it is a public health concern to evaluate whether intake of acrylamide at levels found in the food supply is an important cancer risk factor. Mean dietary intake of acrylamide in adults averages 0.5 microg/kg of body weight per day, whereas intake is higher among children. Several epidemiological studies examining the relationship between dietary intake of acrylamide and cancers of the colon, rectum, kidney, bladder, and breast have been undertaken. These studies found no association between intake of specific foods containing acrylamide and risk of these cancers. Moreover, there was no relationship between estimated acrylamide intake in the diet and cancer risk. Results of this research are compared with other epidemiological studies, and the findings are examined in the context of data from animal models. The importance of epidemiological studies to establish the public health risk associated with acrylamide in food is discussed, as are the limitations and future directions of such studies.
The acrylamide levels in breast milk and the main categories of Swedish baby food products, i.e. breast milk substitute (infant formula), gruel, porridge and canned baby food, have been analysed. Furthermore, the acrylamide intake from these products by children up to one year of age has been estimated. Other kind of foods e.g. biscuits, are not included. Because of the expected low concentrations of acrylamide, a new sample extraction method for detection by liquid chromatography, tandem mass spectrometry, was developed and validated. The lower limit of quantification was 0.5 microg kg(-1) for liquid samples and 2 microg kg(-1) for other samples. The average levels found for gruel, porridge and canned baby food, all ready to eat, were 1.4, 26, and 7.8 microg/kg respectively. We found great variations in the acrylamide levels between and in different food categories,
Despite assumed similarities in Canadian and US dietary habits, some differences in food availability and nutrient fortification exist. Food-frequency questionnaires designed for the USA may therefore not provide the most accurate estimates of dietary intake in Canadian populations. Hence, we undertook to evaluate and modify the National Cancer Institute's Diet History Questionnaire (DHQ) and nutrient database.
Of the foods queried on the DHQ, those most likely to differ in nutrient composition were identified. Where possible these foods were matched to comparable foods in the Canadian Nutrient File. Nutrient values were examined and modified to reflect the Canadian content of minerals (calcium, iron, zinc) and vitamins (A, C, D, thiamin, riboflavin, niacin, B6, folate and B12). DHQs completed by 13 181 Alberta Cohort Study participants aged 35-69 years were analysed to estimate nutrient intakes using the original US and modified versions of the DHQ databases. Misclassification of intake for meeting the Dietary Reference Intake (DRI) was determined following analysis with the US nutrient database.
Twenty-five per cent of 2411 foods deemed most likely to differ in nutrient profile were subsequently modified for folate, 11% for vitamin D, 10% for calcium and riboflavin, and between 7 and 10% for the remaining nutrients of interest. Misclassification with respect to meeting the DRI varied but was highest for folate (7%) and vitamin A (7%) among men, and for vitamin D (7%) among women over 50 years of age.
Errors in nutrient intake estimates owing to differences in food fortification between the USA and Canada can be reduced in Canadian populations by using nutrient databases that reflect Canadian fortification practices.
OBJECTIVES: A significant fraction of the Alaska Native population appears to be shifting from a primarily subsistence-based diet to a market-based diet; therefore, the ability to link diet pattern to disease risk has become increasingly important to predicting public health needs. Our research aims to develop the use of stable isotope ratios as diet pattern biomarkers, based on naturally-occurring isotopic differences in the elemental composition of subsistence and non-subsistence foods. These differences are reflected in human blood, hair and fingernail isotope signatures. STUDY DESIGN: In this preliminary study, we investigate the potential for 13C and 15N to serve as dietary biomarkers for age-related dietary differences in a subset of participants involved with a long-term study initiated by the Center for Alaska Native Health Research (CANHR) at the University of Alaska Fairbanks (UAF). METHODS: We measured delta13C and delta15N in red blood cells collected from 12 "elder" participants (age 60+ yrs) and 14 younger participants (age 14-19 yrs). Samples were evenly divided between males and females, and between two villages sampled in 2004. We also sampled market and subsistence foods in Fairbanks, AK, as an indicator of the isotopic differences likely to be observed in village foods. RESULTS: Elders were significantly enriched in 15N, but depleted in 13C, relative to younger participants. These differences are consistent with increased intake of marine subsistence in elders, and of certain market foods in younger participants. However, elders were considerably more variable in delta15N, suggesting greater differences among individuals in their usual intake. CONCLUSIONS: Overall we find that RBC stable isotope signatures exhibit variation consistent with previously documented dietary patterns in Alaska Natives, and we describe future directions for developing these biomarkers for diet pattern monitoring.
OBJECTIVE: To estimate flavonoid intake in the Australian population. DESIGN: Flavonoid consumption was estimated from 24-hour recall data and apparent consumption data using US Department of Agriculture flavonoid composition data. SUBJECTS: The National Nutrition Survey 1995 assessed dietary intake (24-hour recall) in a representative sample (n=13,858) of the Australian population aged 2 years and over. RESULTS: Analysis of the 24-hour recall data indicated an average adult intake (>18 years) of 454 mg day(-1) (92% being flavan-3-ols). Apple was the highest quercetin source until age 16-18 years, after which onion became an increasingly important prominent source. Variations in hesperetin consumption reflected orange intake. Apple, apricot and grapes were the major sources of epicatechin and catechin for children, but subsided as wine consumption increased in adulthood. Wine was the main source of malvidin. Naringenin intake remained static as a percentage of total flavonoid intake until age 19-24 years, corresponding to orange intake, and then increased with age from 19-24 years, corresponding to grapefruit intake. Apparent dietary flavonoid consumption was 351 mg person(-1) day(-1), of which 75% were flavan-3-ols. Black tea was the major flavonoid source (predominantly flavan-3-ols) representing 70% of total intake. Hesperetin and naringenin were the next most highly consumed flavonoids, reflecting orange intake. Both 24-hour recall and apparent consumption data indicated that apigenin intake was markedly higher in Australia than reported in either the USA or Denmark, presumably due to differences in consumption data for leaf and stalk vegetables and parsley. CONCLUSIONS: Tea was the major dietary flavonoid source in Australia. Flavonoid consumption profiles and flavonoid sources varied according to age. More consistent methodologies, survey tools validated for specific flavonoid intakes and enhanced local flavonoid content data for foods would facilitate better international comparisons of flavonoid intake.