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EnvironHealthPerspect113(7):894-899 (2005); https://doi.org/10.1289/ehp.7688 The source of the errors in this article, which were limited to the Boston cohort, was twofold. Specifically, performance IQ data were used instead of full-scale IQ [...]

Recent epidemiological studies suggest that prenatal exposure to bis[p-chlorophenyl]-1,1,1-trichloroethane (DDT), and its main metabolite 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE), impairs psychomotor development (PD) during the first year of life (Eskenazi et al. 2006; [...]

BACKGROUND: Lead exposure in adults is associated with hypertension. Altered prenatal nutrition is associated with subsequent risks of adult hypertension, but little is known about whether prenatal exposure to toxicants, [...]

BACKGROUND: Most toxicologic studies focus on a single agent, although this does not reflect real-world scenarios in which humans are exposed to multiple chemicals. OBJECTIVES: We prospectively studied manganese-lead interactions [...]

BACKGROUND: Cumulative prenatal lead exposure, as measured by maternal bone lead burden, has been associated with smaller weight of offspring at birth and 1 month of age, but no study [...]

BACKGROUND: Evidence suggests that p,p'-dichlorodiphenyldichloroethene (DDE) affects neurodevelopment in infants, although a critical exposure window has not yet been identified. OBJECTIVES: Our goal was to assess the prenatal DDE exposure [...]

BACKGROUND: The impact of prenatal lead exposure on neurodevelopment remains unclear in terms of consistency, the trimester of greatest vulnerability, and the best method for estimating fetal lead exposure. OBJECTIVE: [...]

OBJECTIVE: Low-level postnatal lead exposure is associated with poor intellectual development in children, although effects of prenatal exposure are less well studied. We hypothesized that prenatal lead exposure would have [...]

Lead is a confirmed neurotoxin, but questions remain about lead-associated intellectual deficits at blood lead levels < 10 [micro]g/dL and whether lower exposures are, for a given change in exposure, [...]

We determined the secular trend in blood lead levels in a cohort of 321 children born in Mexico City between 1987 and 1992. Blood lead level was measured every 6 [...]

Objective. A number of prospective studies have examined lead levels in umbilical cord blood at birth as predictors of infant mental development. Although several have found significant inverse associations, others have not. Measurement of lead levels in maternal bone, now recognized as the source of much fetal exposure, has the potential to serve as a better or complementary predictor of lead&apos;s effect on the fetus. Our objective was to compare lead levels in umbilical cord blood and maternal bone as independent predictors of infant mental development using a prospective design. Methods. We recruited women who were giving birth at 3 maternity hospitals in Mexico City that serve a homogeneous middle-class community. Umbilical cord blood lead levels were measured by graphite furnace atomic absorption spectroscopy, and maternal lead levels in cortical (tibial) and trabecular (patellar) bone were measured within 4 weeks of giving birth using a 109-Cd K-x-ray fluorescence instrument. At 24 months of age, each infant was assessed using the Bayley Scales of Infant Development-II (Spanish Version). Results. A total of 197 mother-infant pairs completed this portion of the study and had data on all variables of interest. After adjustment for other well-known determinants of infant neurodevelopment, including maternal age, IQ, and education; paternal education; marital status; breastfeeding duration; infant gender; and infant illness, lead levels in umbilical cord blood and trabecular bone were significantly, independently, and inversely associated with the Mental Development Index (MDI) scores of the Bayley Scale. In relation to the lowest quartile of trabecular bone lead, the second, third, and fourth quartiles were associated with 5.4-, 7.2-, and 6.5-point decrements in adjusted MDI scores. A 2-fold increase in cord blood lead level (eg, from 5 to 10 [micro] g/dL) was associated with a 3.1-point decrement in MDI score, which is comparable to the magnitude of effect seen in previous studies. Conclusion. Higher maternal trabecular bone lead levels constitute an independent risk factor for impaired mental development in infants at 24 months of age. This effect is probably attributable to mobilization of maternal bone lead stores, a phenomenon that may constitute a significant public health problem in view of the long residence time of lead in bone. Pediatrics 2002;110:110-118; lead, bone, epidemiology, neurotoxins., The blood lead level considered to be toxic to children has been revised downward several times during the past 30 years. (1) The accumulated body of research that engendered this [...]

Background: Although growing evidence suggests that early-life excess manganese (Mn) impairs neurodevelopment, data on the neurodevelopmental effects of mancozeb, a fungicide containing Mn, and its main metabolite ethylenethiourea (ETU) are limited. Objective: We examined whether prenatal mancozeb exposure and excess Mn were associated with neurodevelopment in 355 1-y-old infants living near banana plantations with frequent aerial mancozeb spraying in Costa Rica. Methods: We measured urinary ETU, hair Mn, and blood Mn concentrations in samples collected 1-3 times during pregnancy from mothers enrolled in the Infants' Environmental Health (ISA) study. We then assessed neurodevelopment in their 1-y-old infants using the Bayley Scales of Infant and Toddler Development, 3rd edition (BSID-III). We estimated exposure-outcome associations using linear regression models adjusted for maternal education, parity, gestational age at birth, child age, Home Observation for Measurement of the Environment score, and location of neurodevelopmental assessment. Results: Median (P25-P75) urinary ETU, hair Mn, and blood Mn measured during pregnancy were 3.3 [micro]g/L (2.4-4.9; specific gravity-corrected), 1.7 [micro]g/g (0.9-4.1), and 24.0 [micro]g/L (20.3-28.0), respectively. Among girls, higher ETU was associated with lower social-emotional scores [[beta] per 10-fold increase = -7.4points (95% CI: -15.2, 0.4)], whereas higher hair Mn was associated with lower cognitive scores [-3.0 (-6.1, 0.1)]. Among boys, higher hair Mn was associated with lower social-emotional scores [- 4.6 (-8.5, -0.8)]. We observed null associations for blood Mn, language, and motor outcomes. Conclusions: Our findings indicate that maternal exposure to mancozeb and excess Mn during pregnancy may have adverse and sex-specific effects on infant neurodevelopment. https://doi.org/10.1289/EHP1955, Introduction Manganese (Mn) ethylene bis-dithiocarbamate (EBDC) fungicides, such as mancozeb and maneb, are widely used in agriculture and professional turf management (U.S. EPA 2005). EBDCs contain approximately 21% Mn by [...]

BACKGROUND: Some evidence suggests that fluoride may be neurotoxic to children. Few of the epidemiologic studies have been longitudinal, had individual measures of fluoride exposure, addressed the impact of prenatal exposures or involved more than 100 participants. OBJECTIVE: Our aim was to estimate the association of prenatal exposure to fluoride with offspring neurocognitive development. METHODS: We studied participants from the Early Life Exposures in Mexico to Environmental Toxicants (ELEMENT) project. An ion-selective electrode technique was used to measure fluoride in archived urine samples taken from mothers during pregnancy and from their children when 6-12 y old, adjusted for urinary creatinine and specific gravity, respectively. Child intelligence was measured by the General Cognitive Index (GCI) of the McCarthy Scales of Children's Abilities at age 4 and full scale intelligence quotient (IQ) from the Wechsler Abbreviated Scale of Intelligence (WASI) at age 6-12. RESULTS: We had complete data on 299 mother-child pairs, of whom 287 and 211 had data for the GCI and IQ analyses, respectively. Mean (SD) values for urinary fluoride in all of the mothers (n = 299) and children with available urine samples (n = 211) were 0.90 (0.35) mg/L and 0.82 (0.38) mg/L, respectively. In multivariate models we found that an increase in maternal urine fluoride of 0.5 mg/L (approximately the IQR) predicted 3.15 (95% CI: -5.42, -0.87) and 2.50 (95% CI -4.12, -0.59) lower offspring GCI and IQ scores, respectively. CONCLUSIONS: In this study, higher prenatal fluoride exposure, in the general range of exposures reported for other general population samples of pregnant women and nonpregnant adults, was associated with lower scores on tests of cognitive function in the offspring at age 4 and 6-12 y. https:// doi.org/10.1289/EHP655, Introduction Community water, salt, milk, and dental products have been fluoridated in varying degrees for more than 60 y to prevent dental caries, while fluoride supplementation has been recommended to [...]

We thank Ronchetti for his comments on our recent article (Hu et al. 2006). We are aware of what he noted was the wide scatter of points surrounding the correlation [...]