The purpose of the study was to assess the neurocognitive status of 6-month-old infants whose mothers were exposed to low but varying amounts of lead during pregnancy. Lead levels in the cord blood were used to assess environmental exposure and the Fagan Test of Infant Intelligence (FTII) assessed visual recognition memory (VRM). The cohort consisted of 452 infants of mothers who gave birth to babies at 33-42 weeks of gestation between January 2001 and March 2003. The overall mean lead level in the cord blood was 1.42 μg/dl (95% CI: 1.35-1.48). We found that VRM scores in 6 month olds were inversely related to lead cord blood levels (Spearman correlation coefficient −0.16, p = 0.007). The infants scored lower by 1.5 points with an increase by one unit (1 μg/dl) of lead concentration in cord blood. In the lower exposed infants (≤1.67 μg/ dl) the mean Fagan score was 61.0 (95% CI: 60.3-61.7) and that in the higher exposed group (>1.67 μg/dl) was 58.4 (95% CI: 57.3-59.7). The difference of 2.5 points was significant at the p = 0.0005 level. The estimated risk of scoring the high-risk group of developmental delay (FTII classification 3) due to higher lead blood levels was two-fold greater (OR = 2.33, 95% CI: 1.32-4.11) than for lower lead blood levels after adjusting for potential confounders (gestational age, gender of the child and maternal education). As the risk of the deficit in VRM score (Fagan group 3) in exposed infants attributable to Pb prenatal exposure was about 50%, a large portion of cases with developmental delay could be prevented by reducing maternal blood lead level below 1.67 μg/dl. Although the negative predictive value of the chosen screening criterion (above 1.67 μg/dl) was relatively high (89%) its positive predictive value was too low (22%), so that the screening program based on the chosen cord blood lead criterion was recommended.

The purpose of the study was to test the hypothesis whether infants with higher prenatal exposure to fine particles (PM_2.5) are at greater risk of developing respiratory symptoms and whether fish consumption in pregnancy may modulate the effect. The study was carried out in a cohort of 465 newborns in Krakow (Poland) who have been followed over the first 2 years of life and for whom data on the occurrence of respiratory symptoms and measurements of personal air monitoring in the second trimester of pregnancy were available. The incidence risk ratio (IRR) of respiratory symptoms due to prenatal PM_2.5 exposure were adjusted for potential confounders (gender of child, breastfeeding, parity, maternal atopy, maternal education as a proxy for the socio-economic status, exposure to postnatal environmental tobacco smoke (ETS), and moulds in households) in the generalized estimating equations (GEE) statistical models. The adjusted risk of coughing was associated significantly with PM_2.5 level (IRR = 2.51; 95% CI: 1.77–3.58), moulds in the household, parity, maternal atopy and postnatal ETS, but was lower in girls, and in infants whose mothers consumed more fish in pregnancy (IRR = 0.85; 95% CI: 0.79–0.91). The risk of wheezing was also correlated significantly with the prenatal exposure to PM_2.5 (IRR = 1.36; 95% CI: 1.29–1.43) but also with the presence of moulds in homes, parity, maternal atopy and postnatal ETS. The occurrence of wheezing was associated inversely with the gender of child, gestational age, and fish consumption in pregnancy (IRR = 0.97; 95% CI: 0.95–0.99). Similarly, the risk of difficult (puffy) breathing increased with prenatal exposure to PM_2.5 (IRR = 1.18; 95% CI: 1.12–1.25) moulds, maternal atopy, and parity. The symptom occurrence was lower in girls and associated inversely with the gestational age, and fish consumption in pregnancy (IRR = 0.94; 95% CI: 0.92–0.97). The results of the study support the hypothesis that fish consumption in pregnancy may mitigate the harmful effect of prenatal or perinatal exposure to components of PM_2.5 resulting in an increased burden of respiratory infections among infants.

The purpose of this study is to investigate the construct validity of the Harvard Alumni Activity Survey (HAAS) in an urban, lower income population. Data were collected from 192 smokers enrolled in an antioxidant micronutrient trial. Activity data were compared to body mass index (BMI), diastolic, and systolic blood pressure. The traditional physical activity index (PAI), using data on stair climbing, walking, and sports, was calculated including and excluding body mass. A new scale, the total weekly activity (TWA) scale, was derived from other questions on the HAAS. The PAI scale calculated with body mass was unassociated with BMI and blood pressure. The PAI scale calculated without body mass was unassociated with BMI and systolic blood pressure but was associated with diastolic blood pressure (Beta = -0.001, p = 0.03). The TWA scale was associated with BMI (Beta = -0.01, p = 0.01), diastolic (Beta = -0.03, p = 0.01), and systolic blood pressure (Beta = -0.04, p = 0.01). A one standard deviation change in the TWA scale is predicted to be equivalent to a change of 0.99 BMI units, 2.97 mmHg of diastolic blood pressure, and 3.96 mmHg of systolic blood pressure. This work suggests that the TWA scale has greater construct validity than the traditional PAI scale in this population.

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