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Objectives: The goals of this study were two-fold: (1) to assess the relationship between blood lead levels and neurobehavioral test performance in a nationally sample of adults from the third National Health and Nutrition Evaluation Survey and (2) to analyze the results from previously published studies of occupational lead exposure that used the same neurobehavioral tests as those included in the survey., Methods: Regression models were used to test and estimate the relationships between measurements of blood lead and performance on a simple reaction time, a symbol-digit substitution, and a serial digit learning test in adults aged 20-59 years who participated the survey. Mixed models were used to analyze the data from the occupational studies., Results: The blood lead levels of those participating in the survey ranged from 0.7 to 41.8 microg/dl. The estimated geometric mean was 2.51 microg/dl, and the estimated arithmetic mean was 3.30 microg/dl. In the survey, no statistically significant relationships were found between blood lead concentration and performance on the three neurobehavioral tests when adjusted for covariates. In the occupational studies, the groups exposed to lead consistently performed worse than control groups on the simple reaction time and digit-symbol substitution tests., Conclusions: The results from the survey and the occupational studies do not provide evidence for impairment of neurobehavioral test performance at levels below 25 microg/dl, the concentration that the Centers for Disease Control and Prevention define as elevated in adults. The average blood lead level of the exposed groups in the occupational studies was 41.07 microg/dl, less than 50 microg/dl, the minimum concentration that the Occupational Safety and Health Administration requires for medical removal from the workplace. Given the evidence of impaired neurobehavioral performance in these groups, the 50 microg/dl limit should be reevaluated.

LITTLE IS KNOWN ABOUT BLOOD PRESSURE LEVELS and the extent of high blood pressure in Hispanic children and adolescents, especially in groups other than Mexican Americans. The authors of this study investigated the levels of systolic blood pressure (SBP) and diastolic blood pressure (DBP) and the extent of high blood pressure among Mexican-American, Cuban-American, and mainland Puerto Rican children and adolescents who participated in the Hispanic Health and Nutrition Examination Survey (HHANES). Very few children and adolescents in these three Hispanic groups had high normal or high blood pressure. Puerto Rican children had significantly lower DBP than Mexican-American (2.4 mmHg) and Cuban-American (1.8 mmHg) children. Their SBP was also lower (1.7 mmHg) than that of Cuban-American children. These findings should be interpreted cautiously, however, since a significant observer effect was also found in this study. Correlates of blood pressure in children in all three Hispanic groups were consistent with those found in studies of other ethnic groups. Age, body mass index, and pulse rate were significant predictors of both SBP and DBP (P less than 0.05). Gender was an important predictor of SBP but not DBP. Socioeconomic and cultural factors were not significant predictors of blood pressure in these Hispanic groups.

DESPITE THEIR HIGHER PREVALENCE of obesity and diabetes, Hispanics have lower or equal rates of hypertension than non-Hispanic whites (1-4). Healthy People 2000 objectives call for increasing the proportion of hypertensive men whose blood pressure is under control to at least 40%. In addition, the objectives recommend reducing the prevalence of overweight to 41% among hypertensive women, and to 35% among hypertensive men (5). The Hispanic Health and Nutrition Examination Survey (HHANES) collected data on Mexican Americans (MA), Cuban Americans (CA), and Puerto Ricans (PR) living in the continental United States. A trained physician measured systolic (SBP) and diastolic (DBP) blood pressure twice in one visit. Our findings provide data to assess baseline estimates for several Healthy People 2000 objectives among Hispanics. Based on criteria from The Fifth Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC-V), we found Hispanic women to have higher rates of awareness, treatment, and control of hypertension than men. Only 8% of MA and PR men and 9% of CA men who were hypertensive had their high blood pressure under control. The prevalence of overweight among hypertensive men ranged from 39% to 60%; and among hypertensive women, from 44% to 74%. Hispanic women with six or fewer years of education had higher prevalence of hypertension and other cardiovascular disease (CVD) risk factors. Future research should investigate the socioeconomic factors associated with the presence of these risk factors.