ABSTRACT. Background. Children are commonly exposed at background levels to several ubiquitous environmental pollutants, such as lead and persistent organic pollutants, that have been linked to neurologic and endocrine effects. These effects have prompted concern about alterations in human reproductive development. Few studies have examined the effects of these toxicants on human sexual maturation at levels commonly found in the general population, and none has been able to examine multiple toxicant exposures. The aim of the current investigation was to examine the relationship between attainment of menarche and levels of 6 environmental pollutants to which children are commonly exposed at low levels, ie, dichlorodiphenyldichloroethylene (p,p-DDE), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), mirex, lead, and mercury.Methods. This study was conducted with residents of the Akwesasne Mohawk Nation, a sovereign territory that spans the St Lawrence River and the boundaries of New York State and Ontario and Quebec, Canada. Since the 1950s, the St Lawrence River has been a site of substantial industrial development, and the Nation is currently adjacent to a US National Priority Superfund site. PCB, p,p-DDE, HCB, and mirex levels exceeding the US Food and Drug Administration recommended tolerance limits for human consumption have been found in local animal species. The present analysis included 138 Akwesasne Mohawk Nation girls 10 to 16.9 years of age. Blood samples and sociodemographic data were collected by Akwesasne community members, without prior knowledge of participants' exposure status. Attainment of menses (menarche) was assessed as present or absent at the time of the interview. Congener-specific PCB analysis was available, and all 16 PCB congeners detected in >50% of the sample were included in analyses (Interna- , 153, 180, and 187). Probit analysis was used to determine the median age at menarche for the sample. Binary logistic regression analysis was used to determine predictors of menarcheal status. Six toxicants (p,p-DDE, HCB, PCBs, mirex, lead, and mercury) were entered into the logistic regression model. Age, socioeconomic status (SES), and BMI were tested as potential cofounders and were included in the model at P < .05. Interactions among toxicants were also evaluated.Results. Toxicant levels were measured in blood for this sample and were consistent with long-term exposure to a variety of toxicants in multiple media. Mercury levels were at or below background levels, all lead levels were well below the Centers for Disease Control and Prevention action limit of 10 g/dL, and PCB levels were consistent with a cumulative, continuing exposure pattern. The median age at menarche for the total sample was 12.2 years. The predicted age at menarche for girls with lead levels above the median (1.2 g/dL) was 10.5 months later than that for girls with lead levels below the median. In the logistic regression analysis, age was the strongest predictor of menarcheal status and SES was also a significa...

To determine the influences of maternal diet and nutrition during pregnancy on the blood lead level of neonates, we conducted a study of mother-infant pairs from lower socioeconomic circumstances living in Albany County, New York. Maternal blood lead (MBPb), anthropometry, and diet were assessed in each trimester. Neonates' blood lead (NBPb) levels were low (geometric mean = 1.58 micro g/dL), and none had elevated blood lead. More than 50% of the mothers had intakes below the recommended dietary allowances for zinc, calcium, iron, vitamin D, and kilocalories. As expected, MBPb was strongly and positively related to NBPb. Among the anthropometric measures of maternal nutritional status, variables measuring gain in weight and arm circumference were negatively related to NBPb. In multivariable models reflecting different analytic strageties and including MBPb, anthropometry, and sociodemographic characteristics, dietary intakes of iron and vitamin D were negatively related to NBPb. The effect of zinc varied substantially depending on model covariates. Effects of dietary constituents are difficult to distinguish, given the intercorrelated nature of nutrients in the diet. Nevertheless, the influences of maternal anthropometric variables, iron, and vitamin D on neonatal lead levels are clear in our analyses.

To determine whether levels of blood lead during gestation and infancy that are below the CDC action of level of 10 μg/dL affect infant growth, we studied 211 disadvantaged mother-infant pairs from Albany, NY. Mothers’ lead levels were low (2nd trimester x=2.8 μg/dL) as were infants’ (x= 3.3 μg/dL at 6 months; 6.4 μg/dL at 12 months). Multiple linear regression analyses showed that 2nd trimester lead levels were related to reduced head circumference at 6 and 12 months. Infants of mothers with 2nd trimester lead at or above the median (≥ 3 ug/dL) exhibited negative associations between blood lead and head circumference at 6 and 12 months, and with weight-for-age, weight-for-length and upper arm circumference at 6 months, but those below the median did not. Infants’ 6 month lead level was related to head circumference at 12 months in the total sample, and in the sub-sample of infants whose blood lead was above the infants’ 6 month blood lead median. Infants also were grouped by changes in their relative blood lead status, i.e., above vs. below the median, from 2nd trimester to 12 months of age. Infants whose lead levels changed from above to below the median were larger than infants whose lead levels went from below to above the median. The results suggest that lead may affect some dimensions of infant growth at levels below 10 ug/dL, but effects of lead levels less than 3 ug/dL are not evident in this sample.