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Volatile organic compounds (VOCs) play an important role in the formation of ground-level ozone and secondary organic aerosol (SOA), and they have been key issues in current air pollution prevention and control in China. Considerable attention has been paid to industrial activities due to their large and relatively complex VOCs emissions. The present research aims to provide a comprehensive review on whole-process control of industrial VOCs, which mainly includes source reduction, collection enhancement and end-pipe treatments. Lower VOCs materials including water-borne ones are the keys to source substitution in industries related to coating and solvent usage, leak detection and repair (LDAR) should be regarded as an efficient means of source reduction in refining, petrochemical and other chemical industries. Several types of VOCs collection methods such as gas-collecting hoods, airtight partitions and others are discussed, and airtight collection at negative pressure yields the best collection efficiency. Current end-pipe treatments like UV oxidation, low-temperature plasma, activated carbon adsorption, combustion, biodegradation, and adsorption-combustion are discussed in detail. Finally, several recommendations are made for future advanced treatment and policy development in industrial VOCs emission control. [Display omitted] [ABSTRACT FROM AUTHOR]

The literature has not reached a consensus on the age when peak bone mass is achieved. This study examines growth patterns of total bone mineral content (TBMC) and total bone mineral density (TBMD), peak bone mass, effect of concurrent anthropometry measures, and physical activity on growth patterns in a sample of 312 white males and 343 females aged 8–30 yr. We analyzed data from participants enrolled in Fels Longitudinal Study. Descriptive analysis was used to ascertain characteristics of participants and growth patterns of TBMC and TBMD. Mixed effects models were applied to predict ages at attainment of peak TBMC and TBMD and assess the effects of height, weight, body mass index (BMI), and habitual physical activity on the attainment. Significant differences between sexes were observed for measures of TBMC and TBMD, and differences varied with age. For females, predicted median ages at peak TBMC and TBMD attainments are 21.96 yr (interquartile range [IQR]: 21.81–22.21) and 22.31 yr (IQR: 21.95–22.59), respectively. For males, predicted median ages are 23.34 yr (IQR: 24.34–26.19) and 26.86 yr (IQR: 25.14–27.98) respectively. For females, height, weight, and BMI, but not physical activity, had significant influences on attainment of TBMC and TBMD ( p < 0.01). For males, weight and BMI, but not height and physical activity, exerted significant influence on attainment of TBMC and TBMD ( p < 0.01), and also modified correlations between age and peak TBMC and TBMD. Our results suggest that (1) for both sexes, trajectories of TBMC and TBMD follow a curvilinear pattern between ages 8 and 30 yr; (2) predicted ages at peak TBMC and TBMD are from early to late 20s for both white males and females, with females reaching their peaks significantly earlier than males; and (3) concurrent height, weight, and BMI, but not habitual physical activity, exert significant effects on trajectories of TBMC and TBMD. [ABSTRACT FROM AUTHOR]

Background: Evidence shows that some causes of the metabolic syndrome (MS) begin in childhood, which could indicate a familial association, through either genetic inheritance or cohabitation. Objective: This study examined associations between parents and adult offspring diagnoses of the MS and its risk factors. Design: Measurements were obtained from adult participants and their adult offspring enrolled in the Fels Longitudinal Study, with simultaneous waist circumference, systolic blood pressure (SBP), diastolic blood pressure (DBP), triglycerides, HDL, and glucose observations used for diagnosis. On the basis of repeated measurements (in some cases), adult participants were classified as having the MS at least once or as never having the MS. Chi-square tests, ORs, and mixed-effects models were used to study familial associations. Results: Maternal (OR: 2.5; 95% CI: 1.1, 5.5) and paternal (OR: 4.1; 95% CI: 1.4, 12.1) MS classifications were significantly associated with MS classification in sons. MS classification in mothers and daughters (OR: 2.7; 95% CI: 0.9, 8.7; P = 0.08) was similar to that in sons but was not significant, whereas fathers and daughters were not associated (OR: 1.1; 95% CI: 0.4, 3.5). Maternal MS diagnoses were significantly and positively associated with triglycerides in male offspring and were significantly associated with SBP, DBP, and triglycerides in females. Paternal diagnoses were significantly associated only with DBP and HDL in male offspring. Conclusions: Parental MS diagnosis is significantly associated with MS diagnosis in adult male offspring, and adverse levels of certain risk factors are associated between offspring and parents, although these associations vary across risk factors and child sex. [ABSTRACT FROM AUTHOR]

The effects of adding fiber to the tolerance of a peptide-based formula have not been studied. The objective of this study was to evaluate the tolerance of a peptide-based formula with insoluble and prebiotic fiber in children with compromised gut function. During January 2005 to June 2006, a 6-week randomized, double-blind, cross-over clinical study was conducted to compare stool frequency, stool consistency, and tolerance (abdominal pain, abdominal distension, vomiting, weight gain, and intake) between a formula with or without 3.5 g fructo-oligosaccharides and 3.8 g insoluble fiber/L. Fourteen children with gastrointestinal dysmotility (n=9), Crohn''s disease (n=3), or mild short bowel syndrome (n=2) were randomized to receive one of two formulas for 2 weeks followed by a 5-day washout period and then the second diet for another 2 weeks. Means and standard deviations of daily stool frequency and consistency were calculated and compared using intent-to-treat analysis. Linear mixed models were applied to each outcome variable. Stool frequency did not differ by formula. Stool consistency did differ with more soft “mushy” stools (less hard stools) occurring with use of fiber (P<0.001) and more watery stools occurring with control formula (P<0.01). The extremes of stool consistency were normalized with the fiber formula. No significant differences were observed in vomiting, abdominal pain, feeding intakes, or weight gain between the two formulas. This study showed that a peptide-based formula containing fiber was as well-tolerated as a fiber-free formula in a small population of children with gastrointestinal impairments. Longer-term effects of the fiber formula need to be studied. [Copyright &y& Elsevier]

Objectives: To determine the age of significant divergence in body mass index (BMI) and waist circumference in adults with and without the metabolic syndrome, and to provide age- and sex-specific childhood values that predict adult metabolic syndrome. Study design: Part 1 of this study is a retrospective cohort study of 92 men and 59 women (mean age, 51 years) who had metabolic syndrome and 154 randomly selected adults matched for age and sex who did not have the syndrome. Part 2 is a study of predictive accuracy in a validation sample of 743 participants. Results: The first appearance of differences between adults with and without metabolic syndrome occurred at ages 8 and 13 for BMI and 6 and 13 for waist circumference in boys and girls, respectively. Odds ratios (ORs) for the metabolic syndrome at 30 years and older ranged from 1.4 to 1.9 across age groups in boys and from 0.8 to 2.8 across age groups in girls if BMI exceeded criterion values in childhood. The corresponding ORs for waist circumference ranged from 2.5 to 31.4 in boys and 1.7 to 2.5 in girls. These ORs increased with the number of examinations. Conclusions: Children with BMI and waist circumference values exceeding the established criterion values are at increased risk for the adult metabolic syndrome. [Copyright &y& Elsevier]

Abstract: Purpose: This study investigates the extent to which discordant Tanner stages for sexual maturity indicators are associated with weight and body mass index (BMI) and their variation during adolescence. Discordant children with large differences in weight and BMI may require additional monitoring of their growth during adolescence. Methods: Weight, BMI and Tanner stages, pubic hair in each gender, breast development in girls and genital development in boys, from 2103 boys and 2104 girls aged 8-18 years (average age 13.34 years) from the National Health and Nutrition Examination Survey III (NHANES III, 1988-1994) were analyzed. These cross-sectional data were grouped as concordant: assessed stages for paired indicators were equivalent, or as discordant: assessed stage for one paired indicator was greater or less than the other by one or more stages. Weight and BMI were compared separately by gender and race between concordant and discordant groups using analysis of covariance adjusted for age. Results: Approximately 65-69% of all children were concordant, genital stage equaled pubic hair stage for boys and breast stage equaled pubic hair stage for girls. For all three racial groups, boys whose genital stage was more advanced than their pubic hair stage had significantly smaller weight and BMI (p<.05) than either concordant boys or boys whose pubic hair stage was more advanced than their genital stage. For all three racial groups, girls whose breast stage was more advanced than their pubic hair stage had significantly greater weight and BMI than girls whose pubic hair stage was more advanced than breast stage. Non-Hispanic black and Mexican-American girls whose breast stage was more advanced than their pubic hair stage had significantly greater weight and BMI that the respective concordant girls. Conclusion: Substantial and significant differences occur in weight and BMI among discordant and concordant children, and these differences are larger than between early and late maturing children. [Copyright &y& Elsevier]

Abstract: Purpose: To compare the onset and completion of sexual maturation among U.S. children between 1966 and 1994. Methods: Tanner stages were from 3042 non-Hispanic white boys, 478 black boys, 2625 white girls, and 505 black girls (NHES 1966–70), from 717 Mexican-American boys and 712 Mexican-American girls (HHANES 1982–84) and from 259 non-Hispanic white boys, 411 black boys, 291 white girls, 415 black girls, 576 Mexican-American boys and 512 Mexican-American girls (NHANES III 1988–1994). Proportions of entry into a stage, probit analysis estimated medians and selected percentiles for ages at entry were calculated using SUDAAN. Results: NHANES III (1988–1994) non-Hispanic white boys entered stage 2, 3, and 4 genital development and stages 3 and 4 pubic hair earlier than NHES (1966–1970) white boys, but they entered stage 5 genital development significantly later. NHANES III (1988–1994) Mexican-American boys were in stage 2, 3 and 4 genital development earlier than HHANES (1982–1984) boys, but entry into stage 5 genital and pubic hair development was not significant. NHANES III (1988–1994) white girls entered stage 5 pubic hair later than NHES (1966–1970) white girls. NHANES III (1988–1994) Mexican-American girls entered stage 2 breast and pubic hair development earlier than HHANES (1982–1984) girls, entered stage 4 breast and pubic hair development earlier but entered stage 5 pubic hair later than the HHANES (1982–1984) girls. Conclusion: Persuasive evidence of a secular trend toward early maturation is not found between 1966 and 1994 in non-Hispanic black boys and non-Hispanic black and white girls. Some evidence of this trend is found in non-Hispanic white boys between 1966 and 1994 and in Mexican-American boys and girls between 1982 and 1994. [Copyright &y& Elsevier]

Background: A decline in the age at menarche was recently reported forUSgirls. Although it is possible that this recent drop stems from the concurrent increase in childhood obesity, few longitudinal studies of growth and development have been undertaken to specifically address the temporal relation between growth, adiposity, and the age at menarche. Objective: The objective was to simultaneously examine the effects of birth cohort (secular trend) and rate of maturation (age at menarche) on the timing and pattern of increases in body mass index (BMI) during adolescence in girls. Design:Weapplied mixed-effects polynomial models to serial BMI data, spanning from 6 y before menarche to 6 y after menarche, obtained from 211 girls enrolled in the Fels Longitudinal Study. We examined the effects of birth cohort (defined as girls born 1929- 1946, 1947-1964, and 1965-1983) and age at menarche (defined as ⩽11.9 y, 12.0 -13.1 y, and ⩾13.2 y) on the magnitude and velocity of BMI during adolescence. Results: BMI and BMI velocity in girls born after 1965 were significantly greater than those of girls of earlier birth cohorts, despite stability in the mean age at menarche. Although girls with early menarche tended to have significantly higher BMIs than did girls with average or later menarche, these differences did not emerge until after menarche. Conclusion: These data suggest that increases in relative weight are a consequence, rather than a determinant, of the age at menarche and that secular changes in BMI and in the mean age at menarche could be independent phenomena. [ABSTRACT FROM AUTHOR]

Background: Previous studies to develop and validate bioelectrical impedance analysis (BIA) equations to predict body composition were limited by small sample sizes, sex specificity, and reliance on reference methods that use a 2-component model. Objective: This study was designed to develop sex-specific BIA equations to predict total body water (TBW) and fat-free mass (FFM) with the use of a multicomponent model for children and adults. Design: Data from 5 centers were pooled to create a sample of 1474 whites and 355 blacks aged 12-94 y. TBW was measured by dilution, and FFM was estimated with a multicomponent model based on densitometry, isotope dilution, and dual-energy X-ray absorptiometry. Results: The final race-combined TBW prediction equations included stature²/resistance and body weight (R² = 0.84 and 0.79 and root mean square errors of 3.8 and 2.6 L for males and females, respectively; CV: 8%) and tended to underpredict TBW in black males (2.0 L) and females (1.4 L) and to overpredict TBW in white males (0.5 L) and females (0.3 L). The race-combined FFM prediction equations contained the same independent variables (R² = 0.90 and 0.83 and root mean square errors of 3.9 and 2.9 kg for males and females, respectively; CV: ≈6%) and tended to underpredict FFM in black males (2.1 kg) and females (1.6 kg) and to overpredict FFM in white males (0.4 kg) and females (0.3 kg). Conclusion: These equations have excellent precision and are recommended for use in epidemiologic studies to describe normal levels of body composition. [ABSTRACT FROM AUTHOR]

Objective: To identify risk factors for developing a first febrile status epilepticus (FSE) among children with a first febrile seizure (FS). Study design: Cases were children with a first FS that was FSE drawn from the Consequences of Prolonged Febrile Seizures in Childhood and Columbia cohorts. Controls were children with a first simple FS and separately, children with a first complex FS that was not FSE. Identical questionnaires were administered to family members of the 3 cohorts. Magnetic resonance imaging protocol and readings were consistent across cohorts, and seizure phenomenology was assessed by the same physicians. Risk factors were analyzed using logistic regression. Results: Compared with children with simple FS, FSE was associated with younger age, lower temperature, longer duration (1-24 hours) of recognized temperature before FS, female sex, structural temporal lobe abnormalities, and first-degree family history of FS. Compared with children with other complex FS, FSE was associated with low temperature and longer duration (1-24 hours) of temperature recognition before FS. Risk factors for complex FS that was not FSE were similar in magnitude to those for FSE but only younger age was significant. Conclusions: Among children with a first FS, FSE appears to be due to a combination of lower seizure threshold (younger age and lower temperatures) and impaired regulation of seizure duration. Clinicians evaluating FS should be aware of these factors as many episodes of FSE go unnoticed. Further work is needed to develop strategies to prevent FSE [Copyright &y& Elsevier]

This prospective multicenter study of 200 patients with fever-associated status epilepticus (FSE), of whom 136 underwent a nontraumatic lumbar puncture, confirms that FSE rarely causes cerebrospinal fluid (CSF) pleocytosis. CSF glucose and protein levels were unremarkable. Temperature, age, seizure focality, and seizure duration did not affect results. CSF pleocytosis should not be attributed to FSE. [ABSTRACT FROM AUTHOR]

Objectives: To ascertain the influence of such a prolonged juvenile state on delaying the onset of the metabolic syndrome, cardiovascular disease, and type 2 diabetes mellitus later in life. Study design: We define prolongation of a juvenile state as a retarded tempo of growth, determined by the timing of peak height velocity in each subject and relate the retarded tempo of growth to metabolic syndrome, cardiovascular disease, and type 2 diabetes mellitus later in life by use of serial data of 237 study participants (119 men and 118 women) enrolled in the Fels Longitudinal study. Results: Children who matured early tended to have greater body mass index, waist circumference, and percent of body fat and were more likely to have adverse cardiovascular risk profiles than children who matured late. The differences in these risk factors between early and late maturers were significant for percent body fat, fasting plasma triglycerides, and fasting plasma insulin. Conclusions: The analyses disclosed a clear separation between early and late maturers in the appearance of these risk factors in young adulthood. [Copyright &y& Elsevier]

Objective: To determine whether waist circumference (WC) and family history of disease increase the predictive utility of body mass index (BMI) for adult metabolic syndrome (MetS). Study design: A subsample of 161 men and women from the Fels Longitudinal Study with childhood and adulthood measures were analyzed. Using logistic regression, childhood BMI categories (50th, 75th, and 85th percentiles), WC categories (75th and 90th percentiles), and family history of type 2 diabetes mellitus or cardiovascular disease were modeled separately and in combinations to predict adult MetS. Predicted probabilities and c-statistics were compared across models. Results: The addition of family history to BMI improved the predicted probability of adult MetS from 29% to 52% (Δc-statistic = 0.13). The combination of WC and BMI was more predictive than BMI alone but did not outperform the combination of family history and BMI. In 3 of the 4 models with a combination of family history, WC, and BMI, the predicted probability of adult MetS did not exceed that from the combination of family history and BMI. Conclusions: Family history of type 2 diabetes or cardiovascular disease is a useful addition to BMI in childhood to predict the future risk of adult MetS. [Copyright &y& Elsevier]

Objective: To estimate sensitivity, specificity, and positive and negative predictive values of components of the metabolic syndrome (MetS) during childhood for MetS and type 2 diabetes (T2D) in adulthood. Study design: Data from 3 major studies—the Fels Longitudinal Study, the Muscatine Study, and the Princeton Follow-up Study—were combined to examine how thresholds of metabolic components during childhood determine adult MetS and T2D. Available metabolic components examined in the 1789 subjects included high-density lipoprotein, triglyceride levels, glucose, and percentiles for body mass index, waist circumference, triglycerides, and systolic and diastolic blood pressures. Sensitivity, specificity, and positive and negative predictive values for a refined set of component threshold values were examined individually and in combination. Results: Sensitivity and positive predictive values remained low for adult MetS and T2D for individual components. However, specificity and negative predictive values were fairly high for MetS and exceptionally so for T2D. In combination, having 1 or more of the components showed the highest sensitivity over any individual component and high negative predictive value. Overall, specificity and negative predictive values remained high whether considering individual or combined components for T2D. Conclusions: Sensitivity and positive predictive values on the basis of childhood measures remained relatively low, but specificity and negative predictive values were consistently higher, especially for T2D. This indicates that these components, when examined during childhood, may provide a useful screening approach to identifying children not at risk so that further attention can be focused on those who may be in need of future intervention. [Copyright &y& Elsevier]

Objectives: To examine the patterns of change in cardiometabolic risk factors associated with the metabolic syndrome in children and adolescents between the ages of 8 to 19 years. Study Design: Data of children and adolescents who participated in the Fels Longitudinal Study were analyzed. Body mass index, waist circumference, fasting insulin, fasting glucose, triglycerides, high-density lipoprotein cholesterol, systolic blood pressure, and diastolic blood pressure were assessed annually with a standardized protocol. Results: The proportion of participants having at least 1 change between states of high and normal risk ranged from of 11.0% for body mass index to 30.4% for triglycerides. Youth in the high-risk category at baseline had a higher proportion having changed their status for all risk factors (all P < .05) except waist circumference compared with those in the normal-risk category. There were significant time effects for all risk factors (all P < .01) except fasting glucose and triglyceride levels in metric scores, but insignificant time effects for all risk factors in Z-scores in growth curve analyses. Conclusions: The cardiometabolic risk factors associated with the MetS were relatively stable among white children and adolescents in the normal risk category. Changes in status were common if the risk factor was elevated. [Copyright &y& Elsevier]

Objective: To test the fit and stability of 3 alternative models of the metabolic syndrome''s factor structure across 3 developmental stages. Study design: With data from the Fels Longitudinal Study, confirmatory factor analyses tested 3 alternative models of the factor structure underlying relationships among 8 metabolic syndrome-associated risks. Models tested were a 1-factor model (A), a 4-factor model (B), and a second-order latent factor model (C). Developmental stages assessed were prepuberty (ages 8-10), puberty (ages 11-15), and postpuberty (ages 16-20). Results: Convergence was achieved for all developmental stages for model A, but the fit was poor throughout (root mean square error of approximation > 0.1). Standardized factor loadings for waist circumference and body mass index were much stronger than those for fasting insulin at all 3 time points. Although prepuberty and postpuberty models converged for models B and C, each model had problems with Heywood cases. The puberty model did not converge for either model B or C. Conclusions: The hypothetical structures commonly used to support the metabolic syndrome concept do not provide adequate fit in a pediatric sample and may be variable by maturation stage. A components-based approach to cardiovascular risk reduction, with emphasis on obesity prevention and control, may be a more appropriate clinical strategy for children and youth than a syndromic approach. [Copyright &y& Elsevier]

Abstract: The genetic influences on bone mass likely change throughout the life span, but most genetic studies of bone mass regulation have focused on adults. There is, however, a growing awareness of the importance of genes influencing the acquisition of bone mass during childhood on lifelong bone health. The present investigation examines genetic influences on childhood bone mass by estimating the residual heritabilities of different measures of second metacarpal bone mass in a sample of 600 10-year-old participants from 144 families in the Fels Longitudinal Study. Bivariate quantitative genetic analyses were conducted to estimate genetic correlations between cortical bone mass measures, and measures of bone growth and development. Using a maximum likelihood-based variance components method for pedigree data, we found a residual heritability estimate of 0.71 for second metacarpal cortical index. Residual heritability estimates for individual measures of cortical bone (e.g., lateral cortical thickness, medial cortical thickness) ranged from 0.47 to 0.58, at this pre-pubertal childhood age. Low genetic correlations were found between cortical bone measures and both bone length and skeletal age. However, after Bonferonni adjustment for multiple testing, ρ G was not significantly different from 0 for any of these pairs of traits. Results of this investigation provide evidence of significant genetic control over bone mass largely independent of maturation while bones are actively growing and before rapid accrual of bone that typically occurs during puberty. [Copyright &y& Elsevier]

Abstract: Circulating concentrations of inflammatory markers predict cardiovascular disease (CVD) risk and are closely associated with obesity. However, little is known concerning genetic influences on serum levels of inflammatory markers. In this study, we estimated the heritability (h 2) of soluble cellular adhesion molecule (sCAM) concentrations and examined the correlational architecture between different sCAMs. The study population included 234 men and 270 women aged 18–76 years, belonging to 121 families participating in the Fels Longitudinal Study. Serum levels of soluble intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1), E-selectin (sESEL-1) and P-selectin (sPSEL-1) were assayed using commercially available kits. A variance components-based maximum likelihood method was used to estimate the h 2 of the different serum inflammatory markers while simultaneously adjusting for the effects of known CVD risk factors, such as age and smoking. Additionally, we used bivariate extensions of these methods to estimate genetic and random environmental correlations among sCAMs. Levels of sCAMs were significantly heritable: h 2 =0.24±0.10 for sICAM-1, h 2 =0.22±0.10 for sVCAM-1, h 2 =0.50±0.11 for sESEL-1, and h 2 =0.46±0.10 for sPSEL-1. In addition, a significant genetic correlation (ρ G =0.63) was found between sICAM-1 and sVCAM-1 indicating some degree of shared genetic control. In the Fels Longitudinal Study, the levels of four sCAMs are significantly influenced by genetic effects, and sICAM-1 shares a common genetic background with sVCAM-1. [Copyright &y& Elsevier]

Background: There are few studies of total body water (TBW) volume in children. Such studies are needed, as are new prediction equations for the clinical management of children with renal insufficiency and those receiving dialysis.Methods: Mixed longitudinal data were from 124 white boys and 116 white girls 8 to 20 years of age. TBW volume was measured by deuterium nuclear magnetic resonance spectroscopy, and random effects models were used to determine patterns of change over time. Sex-specific TBW prediction equations were developed using regression analysis.Results: Boys had significantly greater (P < 0.05) mean TBW volumes than girls at all but 3 ages. TBW was significantly (P < 0.05) associated with age and maturation in the boys and the girls. In boys, mean TBW/WT varied from 0.55 to 0.59, while in the girls the mean declined from 0.53 to 0.49 by 16 years of age. Boys had significantly larger means for TBW/WT than girls, who had a significant, slight negative trend with age. The prediction equations were TBW = -25.87 + 0.23 (stature) + 0.37 (weight) for boys and TBW =-14.77 + 0.18 (stature) + 0.25 (weight) for girls.Conclusion: Means are provided for TBW in white children from 8 to 20 years of age, whose average fatness affected the percentage of TBW in body weight. These updated TBW prediction equations perform better than those available from the past. [ABSTRACT FROM AUTHOR]

Abstract: Quantitative ultrasound (QUS) measurements of bone have been reported to predict osteoporotic fracture risk in postmenopausal women and older men. Although many studies have examined the heritability of bone mineral density (BMD), few studies have estimated the heritability of calcaneal QUS phenotypes. In the present study, we examined the genetic regulation of calcaneal QUS parameters in individuals from nuclear and extended families. The study population includes 260 men and 295 women aged 18–91 years (mean ± SD: 46 ± 16 years) who belong to 111 pedigrees in the Fels Longitudinal Study. Three measures of calcaneal structure were collected from both the right and left heel using the Sahara® bone sonometer. These measures included broadband ultrasound attenuation (BUA), speed of sound (SOS), and the quantitative ultrasound index (QUI). We used a variance components based maximum likelihood method to estimate the heritability of QUS parameters while simultaneously adjusting for covariate effects. Additionally, we used bivariate extensions of these methods to calculate additive genetic and random environmental correlations among QUS measures. All phenotypes demonstrated statistically significant heritabilities (P < 0.0000001). Heritabilities in the right heel (h2 ± SE) were h2 = 0.59 ± 0.10 for BUA, h2 = 0.73 ± 0.09 for SOS, and h2 = 0.72 ± 0.09 for QUI. Similarly, heritabilities for the left heel were h2 = 0.52 ± 0.10, h2 = 0.75 ± 0.10, and h2 = 0.70 ± 0.10, respectively. There was evidence for significant genetic and environmental correlations among these six QUS measures. Combinations of QUS measures in the right and left heel demonstrated genetic correlations of 0.94–0.99 and all were significantly different from one indicating at least a partially unique genetic architecture for each of these measures. This study demonstrates that QUS measures of the calcaneus among healthy men and women are heritable, and there are large shared additive genetic effects among all of the traits examined. [Copyright &y& Elsevier]