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A Aro

Publications and source records attributed to A Aro.

At least 19 recordsLinked to original sources
PubMed1999

Evaluation of a food frequency questionnaire with weighed records, fatty acids, and alpha-tocopherol in adipose tissue and serum.

The authors examined the validity of a self-administered 180-item food frequency questionnaire in 125 Norwegian men aged 20-55 years who filled in the questionnaire and completed 14-day weighed records in fall 1995 to winter 1995/6. Spearman correlation coefficients between the two measurements ranged from 0.42 for percent of energy from fat to 0.66 for sugar intake (median r = 0.51). On average, 39% of the men were classified in the same quartile with the two methods, and 3% in the opposite quartile. Correlation coefficients between intake of fatty acids estimated from the questionnaire and the relative amounts of fatty acids in adipose tissue were: linoleic acid (18:2, n-6), r = 0.38; alpha-linolenic acid (18:3, n-3), r = 0.42; eicosapentaenoic acid (20:5, n-3), r = 0.52; and docosahexaenoic acid (22:6, n-3), r = 0.49. The correlations for these fatty acids between the total serum lipids and the diet were 0.16, 0.28, 0.51 and 0.52, respectively. The data suggest that very-long-chain n-3 fatty acids in adipose tissue and total serum lipids reflect the dietary intake of very-long-chain n-3 fatty acids to the same degree. No associations were observed between intake of alpha-tocopherol and concentration in adipose tissue and serum.

Adipose Tissue↗
PubMed1999

Validated method for the quantitation of quercetin from human plasma using high-performance liquid chromatography with electrochemical detection.

A validated method for the quantitation of trace levels of quercetin from human plasma to be used in pharmacokinetic and biomarker studies is presented. Quercetin conjugates were hydrolysed enzymatically, plasma proteins were removed using a Bond Elut C18 extraction column and additional interferences were removed by extracting them into a toluene-dichloromethane mixture. The HPLC system consisted of an Inertsil ODS-3 column (250 x 4.0 mm) and a mobile phase with 59% methanol in phosphate buffer (pH 2.4). High selectivity and a low quantitation limit (0.63 microg/l) were achieved by using electrochemical detection at a low potential. The method has excellent reproducibility: R.S.D. values of peak-heights were 2% and 7.9%, respectively, for within-day and between-day precision. The method was applied to a small scale study of quercetin pharmacokinetics and quercetin was shown to be absorbed from a 20 mg dose. No free quercetin was detected in plasma and no evidence of significant amounts of quercetin glycosides in plasma was found.

Chromatography, High Pressure Liquid↗
PubMed1999

Intake of fatty acids in western Europe with emphasis on trans fatty acids: the TRANSFAIR Study.

OBJECTIVE: To assess the intake of trans fatty acids (TFA) and other fatty acids in 14 Western European countries. DESIGN AND SUBJECTS: A maximum of 100 foods per country were sampled and centrally analysed. Each country calculated the intake of individual trans and other fatty acids, clusters of fatty acids and total fat in adults and/or the total population using the best available national food consumption data set. RESULTS: A wide variation was observed in the intake of total fat and (clusters) of fatty acids in absolute amounts. The variation in proportion of energy derived from total fat and from clusters of fatty acids was less. Only in Finland, Italy, Norway and Portugal total fat did provide on average less than 35% of energy intake. Saturated fatty acids (SFA) provided on average between 10% and 19% of total energy intake, with the lowest contribution in most Mediterranean countries. TFA intake ranged from 0.5% (Greece, Italy) to 2.1% (Iceland) of energy intake among men and from 0.8% (Greece) to 1.9% among women (Iceland) (1.2-6.7 g/d and 1.7-4.1 g/d, respectively). The TFA intake was lowest in Mediterranean countries (0.5-0.8 en%) but was also below 1% of energy in Finland and Germany. Moderate intakes were seen in Belgium, The Netherlands, Norway and UK and highest intake in Iceland. Trans isomers of C18:1 were the most TFA in the diet. Monounsaturated fatty acids contributed 9-12% of mean daily energy intake (except for Greece, nearly 18%) and polyunsaturated fatty acids 3-7%. CONCLUSION: The current intake of TFA in most Western European countries does not appear to be a reason for major concern. In several countries a considerable proportion of energy was derived from SFA. It would therefore be prudent to reduce intake of all cholesterol-raising fatty acids, TFA included.

Adult↗
PubMed1999

Omega-3 fatty acids in adipose tissue and risk of myocardial infarction: the EURAMIC study.

Omega-3 fatty acids have potential antiatherogenic, antithrombotic, and antiarrhythmic properties, but their role in coronary heart disease remains controversial. To evaluate the association of omega-3 fatty acids in adipose tissue with the risk of myocardial infarction in men, a case-control study was conducted in eight European countries and Israel. Cases (n=639) included patients with a first myocardial infarction admitted to coronary care units within 24 hours from the onset of symptoms. Controls (n=700) were selected to represent the populations originating the cases. Adipose tissue levels of fatty acids were determined by capillary gas chromatography. The mean (+/-SD) proportion of alpha-linolenic acid was 0.77% (+/-0.19) of fatty acids in cases and 0.80% (+/-0.19) of fatty acids in controls (P=0.01). The relative risk for the highest quintile of alpha-linolenic acid compared with the lowest was 0.42 (95% confidence interval [CI] 0.22 to 0.81, P-trend=0.02). After adjusting for classical risk factors, the relative risk for the highest quintile was 0.68 (95% CI 0.31 to 1.49, P-trend=0.38). The mean proportion of docosahexaenoic acid was 0.24% (+/-0.13) of fatty acids in cases and 0.25% (+/-0.13) of fatty acids in controls (P=0. 14), with no evidence of association with risk of myocardial infarction. In this large case-control study we could not detect a protective effect of docosahexaenoic acid on the risk of myocardial infarction. The protective effect of alpha-linolenic acid was attenuated after adjusting for classical risk factors (mainly smoking), but it deserves further research.

Adipose Tissue↗
PubMed1999

The independent contribution of bone and erythrocyte lead to urinary lead among middle-aged and elderly men: the normative aging study.

Plasma is the component of blood from which lead is free to cross cell membranes and cause organ toxicity. Plasma lead levels, however, are extremely low and difficult to measure. Urinary lead originates from plasma lead that has been filtered at the glomerular level; thus, urinary lead adjusted for glomerular filtration rate serves as a proxy for plasma lead levels. In this investigation we examined the interrelationships of lead levels in whole blood corrected by hematocrit [i.e., erythrocyte lead (EPb)], trabecular bone (TBoPb), cortical bone (CBoPb), and urine excreted over 24 hr (UPb); all samples were obtained from 71 middle-aged and elderly men with no known occupational lead exposures. Lead was measured by graphite furnace atomic absorption spectroscopy (blood), K-X-ray fluorescence (bone), and inductively coupled plasma mass spectroscopy (urine). Lead levels were generally low, with mean EPb, TBoPb, and CBoPb values of 13.8, 31.1, and 21.7 microg/g, respectively, and a median UPb value of 6.15 microg/day. In generalized additive models adjusted for body weight and creatinine clearance rate, both EPb and bone lead variables remained independently and significantly associated with UPb. This finding suggests that bone influences plasma lead in a manner that is independent of the influence of erythrocytic lead on plasma lead. Thus, the superiority of bone lead over blood lead in predicting some chronic forms of toxicity may be mediated through bone's influence on plasma lead. In addition, this study suggests that measurement of urinary lead might be useful as a proxy for plasma lead levels in studies of lead toxicity.

Aged↗
PubMed1998

Electrocardiographic conduction disturbances in association with low-level lead exposure (the Normative Aging Study).

Recent research indicates that cumulative exposure to lead may be more toxic than previously thought. This study was undertaken to examine the relation of low-level lead exposure to electrocardiographic (ECG) conduction disturbances among 775 men who participated in the Normative Aging Study (average age 68 years; range 48 to 93). We used K-x-ray fluorescence to measure lead levels in the tibia and patella, and graphite furnace atomic absorption spectroscopy to measure blood lead levels. The mean (SD) values for blood lead, tibia lead, and patella lead were 5.8 (3.4) microg/dl, 22.2 (13.4) microg/g, and 30.8 (19.2) microg/g, respectively. Bone lead levels were found to be positively associated with heart rate-corrected QT and QRS intervals, especially in younger men. Specifically, in men <65 years of age, a 10 microg/g increase in tibia lead was associated with an increase in the QT interval of 5.03 ms (95% confidence interval [CI], 0.83 to 9.22) and with an increase in the QRS interval of 4.83 ms (95% CI, 1.83 to 7.83) in multivariate regression models. In addition, an elevated bone lead level was found to be positively associated with an increased risk of intraventricular block in men <65 years of age and with an increased risk of atrioventricular (AV) block in men > or = 65 years of age. After adjustment for age and for serum high-density lipoprotein (HDL) level, a 10 microg/g increase in tibia lead was associated with an odds ratio (OR) of 2.23 (95% CI, 1.28 to 3.90) for intraventricular block in men <65 years of age and with an OR of 1.22 (95% CI, 1.02 to 1.47) for AV block in men > or = 65 years of age. Blood lead level was not associated with any of the ECG outcomes examined. The results suggest that cumulative exposure to lead, even at low levels, may depress cardiac conduction.

Aged↗
PubMed1998

Cow's milk consumption, disease-associated autoantibodies and type 1 diabetes mellitus: a follow-up study in siblings of diabetic children. Childhood Diabetes in Finland Study Group.

Evidence from case-control studies for the diabetogenicity of introduction of cow's milk-based formulas at early age in infancy is inconclusive. We followed siblings of children with Type 1 diabetes mellitus (Type 1 DM) to investigate a possible relationship between cow's milk consumption during infancy or later in childhood and the emergence of diabetes-associated autoantibodies and progression to clinical Type 1 DM. A cohort of 725 initially unaffected 0 to 25-year-old siblings of 801 index children with Type 1 DM diagnosed in 1986-1989 participated in the study (82% of those invited). The siblings were observed for Type 1 DM associated autoantibodies at intervals of 3-12 months for 4 years, starting from the diagnosis of Type 1 DM in the index child. The follow-up for Type 1 DM started at the same time and ended on 31 October 1995. The combined prevalence of Type 1 DM associated autoantibodies (islet cell antibodies (ICA), insulin autoantibodies (IAA), GAD autoantibodies (GADA), and/or antibodies to the insulinoma associated cDNA2 protein (IA-2A)) was 13.6% (95/697) at the beginning of the study. Of the initially seronegative siblings, 7.5% (45/602) converted to antibody positivity during 4 years, and of all siblings 4.6% (33/725) developed Type 1 DM during the total follow-up time. The age at introduction of supplementary milk feeding was not significantly related to seroconversion to positivity for Type 1 DM associated autoantibodies or to the development of Type 1 DM in the siblings. When adjusted for age, sex, infant feeding patterns, and maternal age and education, high milk consumption in childhood (> or =3 glasses daily) was associated with more frequent emergence of Type 1 DM-associated autoantibodies than low consumption (<3 glasses daily) (adjusted odds ratio 3.97, 95% confidence interval 1.3-11.7, p = 0.01). There was a non-significant association between high milk consumption and progression to clinical Type 1 DM (adjusted hazard ratio 2.75, 95% confidence interval 0.9-8.4, p = 0.07). To conclude, this study suggests that high consumption of cow's milk during childhood may be associated both with seroconversion to positivity for diabetes-associated autoantibodies and progression to clinical Type 1 DM among siblings of children with diabetes.

Adolescent↗
PubMed1998

Lack of effect on blood pressure by low fat diets with different fatty acid compositions.

We compared the effects on blood pressure (BP) of three isocaloric diets with reduced total fat and saturated fatty acid (SAFA) contents but with different proportions of monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA). Diet LF (low fat) provided 20 en% fat (7.9% SAFA, 7.8% MUFA, 3.0% PUFA); diet HP (high PUFA) 26 en% fat (7.5% SAFA, 8.2% MUFA, 8.1% PUFA), and diet HM (high MUFA) 26 en% fat (7.3% SAFA, 14.1% MUFA, 3.2% PUFA). The diets were consumed for 8 weeks (intervention) preceded by 2 weeks and followed by 8 weeks on a habitual diet (baseline/ switchback) with 33-34 en% fat (13-14% SAFA, 12% MUFA, 6% PUFA). Forty-five free-living couples were randomly allocated into the three diet groups, and 43 men and 44 women completed the study. BP was measured weekly with an automatic device. Compliance to diet was monitored by repeated food records, serum fatty acid compositions, and weekly visits to a nutritionist. Both systolic BP (SBP) and diastolic BP (DBP) remained unchanged throughout the study in all three groups. The weight-adjusted mean (s.e.m.) BP values showed changes in SBP of +1.7 (1.8), -0.4 (1.7), and +1.9 (1.9) mm Hg on the LF, HP, and HM diets, respectively (difference NS), and DBP of +0.1 (1.0), +0.6 (1.0), and -0.3 (1.0) mm Hg, respectively (difference NS) between the last 2 weeks of the baseline and intervention periods. The expected fatty acid intakes were achieved, and there were no between-group differences in change of body weight, intake of dietary fibre and potassium, and 24-h sodium excretion. A reduction in total fat and SAFA intake and changes in the proportions of dietary MUFA and PUFA did not affect the BP levels of this normotensive population with an adequate intake of PUFA at baseline.

Adult↗
PubMed1998

Large number of CD19+/CD23+ B cells and small number of CD8+ T cells as early markers for cow's milk allergy (CMA).

Assessment of activation of immune mechanisms is valuable in the early diagnosis of cow's milk allergy (CMA). The purpose of this study was to evaluate peripheral blood lymphocyte subclasses in children suspected of having CMA and healthy infants in order to detect an early marker for food allergy. Altogether 47 breast-fed infants, aged from 0.4 to 10 months were followed-up prospectively from birth because of atopic heredity. Twenty-three of the infants were healthy and 24 infants had a strong suspicion of and later challenge-proven cow's milk allergy. Leucocyte subsets were determined from peripheral blood mononuclear cells by flow cytometry. In response to a clinical cow's milk challenge, seven infants developed urticaria, 11 infants had eczema, three patients had loose stools, diarrhoea or vomiting and three infants had eczema and diarrhoea, loose stools or vomiting. The total percentage of B cells and also the proportion of B cells bearing a low-affinity IgE receptor as a marker for activation were significantly higher, whereas the percentage of CD8+ T cells was significantly lower in infants with challenge-proven CMA than in healthy controls. These results imply that infants with active CMA have a defect in regulation of B-cell function. Further, they suggest that imbalance of the ratio of suppressor and helper T cells might be an important factor in the etiopathogenesis of CMA. Our results show that large numbers of activated CD19+ B cells and low numbers of CD8+ T cells could be considered as early markers for food allergy since they are already detectable in peripheral blood during the earliest symptoms of CMA.

Antigens, CD19↗
PubMed1998

Similar effects of diets rich in stearic acid or trans-fatty acids on platelet function and endothelial prostacyclin production in humans.

The effects of stearic acid (C18:0) and trans-fatty acids (trans-FAs) on measures of platelet function and prostacyclin (PGI2) production are poorly understood in humans. In this controlled dietary study, platelet function and endothelial PGI2 production were studied in healthy humans after they consumed diets rich in C18:0 or trans-FAs. For 5 weeks, 80 subjects consumed a baseline diet high in saturated FAs and were then switched to a diet containing 9.3% of energy as stearic acid or a diet containing 8.7 energy% as trans-FAs from hydrogenated vegetable oils for another 5 weeks. All diets contained 32.2 to 33.9 energy% fat, 14.6 to 15.8 energy% saturated plus trans-FAs, 12.2 to 12.5 energy% cis-monounsaturated, and 2.9 to 3.5 energy% polyunsaturated FAs. No significant differences between the C18:0 and trans-FA diets were found in the urinary excretion of 2,3-dinor-thromboxane B2 or 2,3-dinor-6-keto-prostaglandin F1alpha. In vitro production of thromboxane B2 by platelets as well as urinary excretion of beta-thromboglobulin were also similar after both diets. Collagen-induced in vitro aggregation was significantly enhanced after the C18:0 diet compared with the trans-FA diet (P=.02), whereas no differences between the diets were found with ADP. The results indicate similar effects of C18:0 and trans-FA diets on platelet activation and endothelial PGI2 production.

Adult↗
PubMed1997

Association between toenail selenium and risk of acute myocardial infarction in European men. The EURAMIC Study. European Antioxidant Myocardial Infarction and Breast Cancer.

The association between selenium status and risk of acute myocardial infarction was examined in a multicenter case-control study in 10 centers from Europe and Israel in 1991-1992. Selenium in toenails was assessed for 683 nonfatal male cases with first acute myocardial infarction and 729 controls less than 70 years of age. Median toenail selenium content was 0.553 microgram/g for cases and 0.590 microgram/g for controls. After adjustment for age, center, and smoking, the odds ratio for myocardial infarction in the highest quintile of selenium as compared with the lowest was 0.63 (95 percent confidence interval 0.37-1.07, p for trend = 0.08). The observed inverse trend was somewhat stronger when the authors adjusted for vitamin E status (p = 0.05). Analysis stratified for smoking habits showed an inverse association in former smokers (odds ratio for the 75th-25th percentile contrast = 0.63 (95 percent confidence interval 0.43-0.94)), but not in current smokers (odds ratio = 0.97 (0.71-1.32)) or in those who had never smoked (odds ratio = 1.55 (0.87-2.76)). Analysis stratified by center showed a significant inverse association between selenium levels and risk of myocardial infarction for Germany (Berlin) only (75th to 25th percentile odds ratio = 0.62 (95 percent confidence interval 0.42-0.91)), which was the center with the lowest selenium levels. It appears that the increased risk of acute myocardial infarction at low levels of selenium intake is largely explained by cigarette smoking; selenium status does not appear to be an important determinant of risk of myocardial infarction at the levels observed in a large part of Europe.

Case-Control Studies↗
PubMed1997

Influence of apolipoprotein A-1 promoter polymorphism on lipid levels and responses to dietary change in Finnish adults.

OBJECTIVES: To analyse the association between the G/A polymorphism in the apolipoprotein A-1 (apo A-1) promoter region and plasma lipid levels, as well as their responses to dietary change, in Finnish adults. SUBJECTS AND DESIGN: Blood samples from 86 subjects (42 men. 44 women) who attended a dietary intervention study carried out in North Karelia in 1993 were available for the current analysis. The diet study consisted of a 2-week baseline period, followed by an 8-week intervention period, and an 8-week switchback period. INTERVENTION: Diet was modified to a low-fat, low-cholesterol diet during the dietary intervention. MAIN OUTCOME MEASURES: Fasting plasma lipid, lipoprotein and apoliprotein levels were determined. RESULTS: At baseline, the high-density lipoprotein (HDL) cholesterol and apo A-1 levels were higher (P < 0.01) and the triglyceride levels were lower (P < 0.05) in men, but not in women, with the A allele. The differences in HDL cholesterol and apo A-1 levels between genotypes remained during the lowfat, low-cholesterol diet and switchback periods. Apart from the difference between responses in apo A-1 during switchback to the original diet, lipid responses to dietary change did not differ significantly between genotypes. CONCLUSION: Our findings indicate a significant association between the apo A-1 promoter polymorphism and plasma apo A-1 and HDL-cholesterol in men. In theory, the higher plasma HDL-cholesterol and apo A-1 levels in the GA/AA group may confer some protection against coronary artery disease. The differences in HDL-cholesterol and apo A-1 levels between genotypes persisted during different diets suggesting that the possible benefit is independent of fat and cholesterol intake.

Adult↗
PubMed1997

Stearic acid, trans fatty acids, and dairy fat: effects on serum and lipoprotein lipids, apolipoproteins, lipoprotein(a), and lipid transfer proteins in healthy subjects.

To compare the effects on serum lipoproteins of stearic acid, trans fatty acids, and dairy fat, 80 healthy subjects consumed a dairy fat-based (baseline) diet for 5 wk, then an experimental diet high in either trans fatty acids (8.7% of energy; n = 40) or stearic acid (9.3% of energy; n = 40) for another 5 wk. All diets provided 32.2-33.9% of energy as fat, 14.6-15.8% as saturated plus trans fatty acids, 11.4-12.5% as cis-monounsaturated fatty acids, 2.9-3.5% as polyunsaturated fatty acids, and 200-221 mg cholesterol/10 MJ. Compared with the dairy fat diet, stearic acid and trans fatty acids decreased serum total cholesterol concentrations similarly (by 13% and 12%, respectively, P < 0.001) but the trans fatty acid diet decreased HDL cholesterol (17%) and apolipoprotein (apo) A-I (15%) significantly more than did the stearic acid diet (11% and 12%, respectively). Stearic acid but not trans fatty acids reduced concentrations of LDL cholesterol and apo B significantly (P < 0.001). The trans fatty acid diet increased the ratio of LDL to HDL cholesterol (19%) and of apo B to apo A-I (16%) more than did the dairy fat diet (P < 0.001) but the stearic acid diet had no effect. Lipoprotein(a) concentrations increased with both experimental diets, significantly more with trans fatty acids (30%) than with stearic acid (10%). In conclusion, high amounts of trans fatty acids had more adverse effects on lipoproteins than did equal amounts of stearic acid and dairy fat. Stearic acid reduced LDL cholesterol, did not affect the ratio of LDL to HDL cholesterol, and increased lipoprotein(a), although to a lesser extent than did trans fatty acids. Dietary fats low in both saturated fatty acids and trans fatty acids should be favored.

Adult↗
PubMed1997

Effect of alpha-tocopherol (vitamin E) and beta-carotene supplementation on the incidence of intermittent claudication in male smokers.

We examined the primary preventive effect of vitamin E (alpha-tocopherol) and beta-carotene supplementation on intermittent claudication. The subjects--participants in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study--were male smokers aged 50 to 69 years who were randomly assigned to receive 50 mg of alpha-tocopherol daily, 20 mg of beta-carotene daily, both, or placebo. At baseline, there were 26 289 men with no history or symptoms of intermittent claudication. The Rose questionnaire on intermittent claudication was administered annually to discover incident cases. We observed 2704 cases of first occurrence of typical intermittent claudication during a median follow-up time of 4.0 years. Compared with placebo, the adjusted relative risk for typical intermittent claudication among those who received alpha-tocopherol only was 1.11 (95% confidence interval, 1.00-1.24); among those who received alpha-tocopherol and beta-carotene, 1.02 (0.91-1.13); and among those who received beta-carotene only, 1.02 (0.92-1.14). When we compared the alpha-tocopherol-supplemented subjects with those who received no alpha-tocopherol, the adjusted relative risk for typical intermittent claudication was 1.05 (0.98-1.14), and for beta-carotene-supplemented subjects compared with those who did not receive beta-carotene, the relative risk was 0.96 (0.89-1.04). In conclusion, no primary preventive effect on intermittent claudication was observed among middle-aged male smokers who were supplemented with alpha-tocopherol, beta-carotene, or both.

Antioxidants↗
PubMed1997

Association of the fatty acid composition of serum phospholipids with hemostatic factors.

It has been suggested that the fatty acid composition of serum phospholipids is an independent risk factor for cardiovascular disease. We examined the association of the fatty acid composition of serum phospholipids with fibrinogen, factor VII antigen (FVII:Ag), factor VII coagulant activity (FVII:C), plasminogen, and lipoprotein(a) [Lp(a)] in 338 men and 363 women 45 to 64 years old. Palmitic acid, the most abundant saturated fatty acid, was positively associated in univariate analyses with plasminogen, which explained 5.2% of its variance among men (P<.0001) and 5.8% among women (P<.0001). Linoleic acid, which is the most abundant polyunsaturated fatty acid, was negatively associated with plasminogen and fibrinogen. This explained 1.1% of the variance in fibrinogen among men (P=.04) and 3.2% among women (P=.0006) and 4.1% of the variance in plasminogen in both sexes (P<.0001). Dihomogammalinolenic acid was positively associated with FVII:Ag and explained 3.7% of its variance among men (P=.0003) and 4.6% among women (P<.0001). Furthermore, dihomogammalinolenic acid was positively and significantly associated with FVII:C, fibrinogen, and plasminogen among women but not among men. All these associations remained significant after adjustment for multiple potential confounding factors such as age, smoking, serum lipids, and body mass index. In conclusion, our findings suggest that linoleic acid, palmitic acid, and dihomogammalinoleic acid are significant independent determinants of hemostatic profile. It is not clear, however, to what extent these results reflect the effects of fatty acids on coagulation and to what extent they reflect the activity of inflammatory processes in the arteries.

8,11,14-Eicosatrienoic Acid↗
PubMed1997

In vivo bone lead measurement in suburban teenagers.

OBJECTIVE: Bone represents a biologically active long-term storage site for lead, and bone lead data on teenagers are limited. Therefore, this study was designed to identify the distribution of bone lead in a teenage population and to explore the environmental and demographic factors associated with bone lead concentrations in young, nonoccupationally exposed subjects. DESIGN: A cross-sectional study of bone lead levels in high school students. PARTICIPANTS: A total of 168 students at a suburban Boston high school. Subjects (90 boys, 78 girls) ranged in age from 13.5 to 19 years and included 40% nonwhite minorities. Of the 168 subjects, 45 lived in homes constructed before 1960. None of the participants reported a history of lead poisoning. OUTCOME MEASURES: Tibial bone lead concentrations were measured in vivo for 60 minutes using K x-ray fluorescence. Lead exposure information was obtained by self-administered questionnaire. RESULTS: Point estimates of bone lead levels ranged from -7.15 to 14.23 microg lead/g bone mineral (microg/g), (mean, 4.0 microg/g; standard deviation, 4.4 microg/g). The reported measurement uncertainties accompanying each of the point estimates ranged from 2.56 to 9.01 microg/g (mean, 3.9 microg/g; standard deviation, 1.0 microg/g). Bone lead levels were not associated with the demographic factors of age, sex, or race. Additionally, current home conditions (housing age, traffic level) were not predictive of bone lead levels, even though these factors were predictive of in-home lead concentrations. CONCLUSIONS: These results demonstrate that although bone lead levels are measurable in this age group, the common predictors of blood and bone lead concentrations are not explanatory for bone lead levels.

Adolescent↗