ABSTRACT
BACKGROUND: The lifelong exposure of the population to acrylamide has raised concerns about the possible health effects of the chemical. Data on the extent of exposure to acrylamide and its primary metabolite, glycidamide, are needed to aid in the assessment of potential health effects. OBJECTIVES: The aim of this study was to assess human exposure to acrylamide and glycidamide in the general U.S. population through the measurement of hemoglobin adducts of acrylamide (HbAA) and glycidamide (HbGA). METHODS: HbAA and HbGA were measured in 7,166 subjects from the National Health and Nutrition Examination Survey. Stratified HbAA and HbGA data were reported by sex, age groups, race/ethnicity (Mexican American, non-Hispanic black, non-Hispanic white), and smoking status based on serum cotinine levels. Covariate-adjusted geometric means for each demographic group were calculated using multiple regression analysis. RESULTS: HbAA and HbGA levels ranged from 3 to 910 and from 4 to 756 pmol/g hemoglobin, respectively, with smokers having the highest levels overall. Tobacco smoke exposure in nonsmokers had a small but significant effect on HbAA and HbGA levels. Adjusted geometric mean levels for children 311 years of age were higher than for adults >or= 60 years of age [mean (95% confidence interval): HbAA, 54.5 (49.1-51.5) and HbGA, 73.9 (71.3-76.6) vs. HbAA, 46.2 (44.3-48.2) and HbGA, 41.8 (38.7-45.2)]. Levels were highest in Mexican Americans [HbAA: 54.8 (51.9-57.8), HbGA: 57.9 (53.7-62.5)], whereas non-Hispanic blacks had the lowest HbGA levels [43.5 (41.1-45.9)]. CONCLUSIONS: U.S. population levels of acrylamide and glycidamide adducts are described. The high variability among individuals but modest differences between population subgroups suggest that sex, age, and race/ethnicity do not strongly affect acrylamide exposure. Adduct concentration data can be used to estimate relative exposure and to validate intake estimates.
Subject(s)
Acrylamide/blood , Environmental Exposure/analysis , Epoxy Compounds/blood , Acrylamide/adverse effects , Adolescent , Adult , Child , Child, Preschool , Environmental Exposure/adverse effects , Epoxy Compounds/adverse effects , Female , Health Surveys , Hemoglobins/chemistry , Hemoglobins/metabolism , Humans , Male , Middle Aged , Nutrition Surveys , Young AdultSubject(s)
Erythrocytes/metabolism , Freezing , Hemoglobins/analysis , Indicator Dilution Techniques , Adult , Female , Humans , Male , Middle AgedABSTRACT
Mild food restriction for 48 h inhibits mating behavior in female musk shrews (Suncus murinus). However, mating behavior is restored after a 90-min feeding bout. In this series of experiments, we examined the role of metabolic fuels in this behavioral restoration. First, drugs reported to block glycolysis or fatty acid oxidation were given 2 h before mating. Both treatments inhibited mating in food-restricted females that were refed after treatment. Blood glucose levels were assessed in females that were fed ad libitum, food restricted, or food restricted and refed for 90 min. Food restriction significantly lowered blood glucose compared with ad libitum feeding or food restriction in combination with 90 min of refeeding. However, neither glucose nor fat alone could substitute for food and promote mating behavior in food-restricted females. In addition, analysis of ketone bodies and body composition in females demonstrated low or undetectable levels of these energy substrates. Our data suggest that musk shrews have relatively little stored energy. Therefore, female musk shrews rely on continuous food intake and monitor multiple cues acutely, including glucose availability and fatty acid oxidation. This ensures that mating does not occur when adequate energy is unavailable.
