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Children’s developing brains are susceptible to pesticides. Less is known about the effect of exposure to chlorpyrifos and pyrethroids on executive functions (EF). We measured urinary 3,5,6-trichloro-2-pyridinol (TCPy), a metabolite of chlorpyrifos, and urinary 3-phenoxybenzoic acid (3-PBA), a general, nonspecific metabolite of pyrethroids in first-grade children from Montevideo, Uruguay (n = 241, age 80.6 ± 6.4 months, 58.1% boys). EFs were assessed with the Intra-dimensional/Extra-dimensional shift (IED), Spatial Span (SSP), and Stockings of Cambridge (SOC) tests from the Cambridge Neuropsychological Test Automated (CANTAB) Battery. General intellectual ability (GIA) was assessed using the Woodcock–Muñoz Cognitive battery. Median (range) urinary TCPy and 3-PBA levels were 16.7 (1.9, 356.9) ng/mg of creatinine and 3.3 (0.3, 110.6) ng/mg of creatinine, respectively. In multivariable generalized linear models, urinary TCPy was inversely associated with postdimensional errors on the IED task β [95% CI]: −0.11 [−0.17, −0.06]. Urinary 3-PBA was inversely associated with the total number of trials −0.07 [−0.10, −0.04], and the total number of errors −0.12 [−0.18, −0.07] on the IED task. When TCPy and 3-PBA were modeled together, the associations did not differ from single-metabolite models. We found no evidence of effect modification by blood lead level (BLL). Pesticide exposure may affect EF performance in urban children.

BACKGROUND: Detoxification of inorganic arsenic (iAs) occurs when it methylates to form monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA). Lower proportions of urinary iAs and MMA, and higher proportions of DMA indicate efficient methylation. The role of B-vitamins in iAs methylation in children with low-level arsenic exposure is understudied. OBJECTIVES: Our study objective was to assess the association between B-vitamin intake and iAs methylation in children with low-level arsenic exposure (

The Latin America and the Caribbean (LAC) region makes up 8.4% of the world's population. Human biomonitoring (HBM) programs, which can shed light on population-level exposure to environmental contaminants such as toxic metals and thus, improve the health of the populations are inexistent in LAC countries. We call for the creation of HBM programs in the region and identify three viable design options for HBM at the individual level, through national surveys, newborn blood collection, and biobanks. We highlight some of challenges to the implementation of HBM programs, including financial and human resources, technical constrains (laboratory), sample, and data logistics. Finally, we provide the case studies of Brazil, Chile, Mexico, and Uruguay, to illustrate a range of responses to toxic metal exposure in non-occupational populations. Although different in many respects, the individual country responses share two commonalities: 1) academic centers drive the research to raise awareness of governmental entities; 2) reference levels are adapted from international norms rather than arising from the studied populations. Well-designed and sufficiently funded biomonitoring systems need to be established in each country of the LAC region. HBM programs are key to promoting human health by informing the public and contributing to policy processes that establish sustainable environmental controls and health prevention programs.

Neighborhood disadvantage (ND) is a risk factor for child behavior problems (CBPs), but is understudied outside the United States and Europe. Our mixed methods study aims to (1) create a culturally meaningful measure of ND, (2) test cross-sectional associations between ND and CBPs and (3) qualitatively explore life in the neighborhoods of families participating in the Salud Ambiental Montevideo (SAM) study.The quantitative study (Study 1) comprised 272, ~7-year-old children with geolocation and complete data on twelve behavioral outcomes (Conner's Teachers Rating Scale - Revised Short Form: CTRS-R:S and Behavioral Rating Inventory of Executive Functioning: BRIEF). A ND factor was created at the census segment level (1,055 segments) with 19 potential indicators of ND downloaded from the Municipality of Montevideo Geographic Services. Children were assigned ND scores based on the location of their household within a census segment. Multilevel models tested associations between ND and all CBP scales, controlling for confounders at the individual level. The qualitative study (Study 2) comprised 10 SAM caregivers. Photovoice alongside semi-structured interviews in Spanish were used to foster conversations about neighborhood quality, activities, and raising children. Thematic analysis with inductive coding was used to summarize qualitative study findings.The ND factor consisted of 12 census-based indicators related to education, employment, ethnicity, housing quality, and age characteristics, but unrelated to home ownership and some ethnicity variables. In multivariable models, ND was associated with greater conduct problems (β = 1.37, p .05), poor shifting (β = 1.56, p .01) and emotional control problems (β = 2.36, p .001). Photovoice and semi-structured interviews yielded four themes: physical disorder, recreation, safety and crime, and community resources. Residents discussed improving waste management and transportation, updating playgrounds, and ensuring neighborhood safety.ND in Montevideo comprised a unique set of census indicators. ND was primarily related to behavioral regulation problems. Hypothesized pathways whereby ND affects CBPs are discussed.

Background Cadmium (Cd) exposure has adverse health effects in children. Diet contributes to Cd exposure, but dietary components could affect body Cd levels. Objective To examine associations between diet and urinary Cd (U-Cd) in children. Methods In this cross-sectional study conducted in Montevideo, Uruguay, Cd exposure of 5–8 year old children (n = 279 with complete data) was assessed in first morning urine (U-Cd), a marker of long-term exposure, measured by ICP-MS and adjusted for specific gravity. Distribution of U-Cd was (median [5%, 95%]: 0.06 [0.02, 0.17] μg/L); data were natural-log-transformed (ln) for statistical analyses. Serum ferritin (SF), an indicator of iron stores, was measured in fasting samples. Trained nutritionists completed two non-consecutive 24-h dietary recalls with both child and caregiver present. Measures of iron, zinc, calcium and fiber intake, and the consumption of grains, root vegetables, milk, and foods rich in heme iron (white and read meats) and non-heme iron (legumes, spinach, broccoli, tomatoes, dried fruit) were derived. Multivariable ordinary least squares (OLS) and ordinal regressions were used to examine associations among tertiles of water Cd, SF, diet, and U-Cd. OLS models were further stratified by sex. Results In covariate-adjusted models, SF was not related to ln-U-Cd. Children in highest tertile of iron and zinc intake had lower ln-U-Cd: (−0.23 [−0.42, −0.03]) and (−0.25 [−0.44, −0.05]), respectively, compared to the reference group. Children consuming higher amounts of foods rich in heme iron had slightly lower ln-U-Cd (−0.17 [−0.36, 0.03]). High grain consumption was related to higher ln-U-Cd (0.25 [0.06, 0.45]). Conclusions Diets rich in grains were related to higher urinary Cd levels among children living in the context of low Cd pollution. Higher intake of iron and zinc was related to lower Cd levels. Given that urinary Cd is mainly a marker of long-term exposure, these findings should be further corroborated.

Children are exposed to many potentially toxic compounds in their daily lives and are vulnerable to the harmful effects. To date, very few non-invasive methods are available to quantify children's exposure to environmental chemicals. Due to their ease of implementation, silicone wristbands have emerged as passive samplers to study personal environmental exposures and have the potential to greatly increase our knowledge of chemical exposures in vulnerable population groups. Nevertheless, there is a limited number of studies monitoring children's exposures via silicone wristbands. In this study, we implemented this sampling technique in ongoing research activities in Montevideo, Uruguay which aim to monitor chemical exposures in a cohort of elementary school children. The silicone wristbands were worn by 24 children for 7 days; they were quantitatively analyzed using gas chromatography with tandem mass spectrometry for 45 chemical pollutants, including polychlorinated biphenyls (PCBs), pesticides, polybrominated diphenyl ethers (PBDEs), organophosphorus flame retardants (OPFRs), and novel halogenated flame-retardant chemicals (NHFRs). All classes of chemicals, except NHFRs, were identified in the passive samplers. The average number of analytes detected in each wristband was 13 ±3. OPFRs were consistently the most abundant class of analytes detected. Median concentrations of ΣOPFRs, ΣPBDEs, ΣPCBs, and dichlorodiphenyltrichloroethane (DDT) and its metabolites (dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD)) were 1020, 3.00, 0.52 and 3.79 ng/g wristband, respectively. Two major findings result from this research; differences in trends of two OPFRs (TCPP and TDCPP) are observed between studies in Uruguay and the United States, and the detection of DDT, a chemical banned in several countries, suggests that children's exposure profiles in these settings may differ from other parts of the world. This was the first study to examine children's exposome in South America using silicone wristbands and clearly points to a need for further studies.

Food and water are common exposure sources of arsenic and lead among children. Whereas dietary sources of these toxicants are fairly well-studied, the contribution of drinking water to toxicant exposures is not well characterized in many populations, particularly in the Global South.To assess the extent to which consumption of household drinking water contributes to arsenic and lead exposure among Uruguayan schoolchildren with low-level exposure.Children, aged 5-8 years, were enrolled into the Salud Ambiental Montevideo study during 2009-2013 from schools in Montevideo, Uruguay. Participants reported water intake as part of two 24-h dietary recalls. Concentrations of arsenic were measured in first morning void urine samples, and adjusted for urinary specific gravity. Lead concentrations were measured in venous blood samples. Drinking water samples were collected from participants' homes and toxicant concentrations measured. Data analyses involved a triangulation approach. First, multivariable linear regressions estimated the associations between toxicant exposure through drinking water, calculated for each child as the product of water intake and water toxicant concentration, and the respective toxicant biomarker concentrations among children with complete data on all variables (Sample A; n = 40). Second, regressions were repeated for participants with complete data on all variables except water intakes (Sample B; n = 195), after water intakes were imputed. Finally, models were constructed for participants of Sample B (n = 195) based on drinking water intakes assumed to be fixed at 25th, 50th, 75th percentile intakes of participants in sample A.Toxicant exposure via drinking water intake was low. The triangulation approach revealed no associations between toxicant exposure through household water intake and the respective toxicant biomarker concentrations.Studies with larger samples and repeated measures are needed to confirm these findings. Nevertheless, it appears that at low water toxicant concentrations, typical water consumption is not a major contributor to children's exposure.

The global burden of water-based lead (Pb) exposure on children is largely unknown; however, the importance of water sources as a path of Pb exposure is receiving increased attention due to recent prominent exposure events related to corroded plumbing infrastructure in the US. This study investigated the contribution of Pb in household drinking and cooking water to Pb levels in blood (PbB) and urine (PbU) within 353 early school-aged children from Montevideo, Uruguay. Additionally, the analysis considered the child's iron status and the water content of iron (WFe) and zinc (WZn) in relation to water Pb and blood/urine Pb concentrations. Lead concentrations for both PbB and PbU were fairly low (M ± SD: 4.2 ± 2.1 μg/dL; Median [5%, 95%]: 1.9 [0.6, 5.1 μg/L, respectively]); however 21% of the sample had a PbB >5 μg/dL but ≤ 10 μg/dL. Overall, there was little evidence of an association between water metal concentrations and children's PbB/PbU. However, when the sample was stratified by children's iron status, WPb was positively related to PbU, but negatively related to PbB in iron-replete children, even after adjusting for WFe and WZn. In iron-deficient children, there was no elevation in PbU with increasing WPb. In this sample of children with low Pb levels, there were no overwhelming relationships between WPb and either PbB or PbU, however, there was some evidence that iron-replete status promotes excretion of WPb.

Oxidative stress (OS) is an important consequence of exposure to toxic metals but it is unclear to what extent low-level metal exposures contribute to OS in children. We examined the cross-sectional association between urinary concentrations of arsenic (As), cadmium (Cd), and lead (Pb) and urinary markers of OS: F2–8α isoprostane and 8-hydroxy-2-deoxy-guanosine (8-OHdG). We also tested effect modification by dietary intakes. Of the 211 children aged 6–8 years living in Montevideo who were eligible for the study because they had at least one OS marker measured via ELISA, 143 were included in a complete-case analysis. Urinary metals were measured with inductively coupled plasma mass spectrometry (ICP-MS: Pb, Cd) and high-performance liquid chromatography online with hydride generation ICP-MS (As-metabolites); concentrations were log2-transformed. All urinary markers were adjusted for specific gravity of urine. Two 24-h dietary recalls were conducted to estimate children's dietary intakes, including total fruit and vegetable consumption and vitamin C, zinc and fiber intake. Ordinary least square (OLS) and weighted quantile sum (WQS) regressions were used to estimate the association between metals and each OS marker as outcome. Metal exposure was generally low: median urinary As, Cd, Pb 9.6 μg/L, 0.06 μg/L and 1.9 μg/L, respectively. Median 8-isoprostane concentration was 1.1 and 8-OHdG 39.6 ng/mL. Log2-transformed urinary As concentrations were positively associated with 8-OHdG concentrations (10.90 [3.82, 17.97]) in covariate-adjusted OLS models which also took account of exposure to Cd and Pb. In WQS, a mixture index was also associated with higher 8-OHdG (8.71 [1.12, 16.3] for each 25% increase in index value), mostly driven by As exposure. There was little evidence of effect modification by dietary antioxidants. In sum, even at low-level, As exposure is associated with detectable oxidative damage to the DNA.

Background Few studies have evaluated the association between low-level arsenic (As) exposure and cognitive performance among children. Objectives In this cross-sectional study, we assessed the association between low-level As exposure and cognitive performance among 5–8 year-old children in Montevideo, and tested effect modification by As methylation capacity and children's dietary folate intake. Methods We measured total urinary As (UAs) concentrations and the proportion of monomethylarsonic acid (MMA) in the urine of 328 children. Seven subtests of the standardized Woodcock-Munoz cognitive battery were used to assess cognitive performance, from which, the general intellectual abilities (GIA) score was derived. Total folate intake was estimated from two 24-h dietary recalls. Linear regression analyses were performed. Effect modification was assessed by stratifying at the median %MMA value and tertiles of total folate intake calculated as micrograms (µg) of dietary folate equivalents (dfe). Results The median UAs was 11.9 µg/l (range = 1.4–93.9), mean folate intake was 337.4 (SD = 123.3) µg dfe, and median %MMA was 9.42 (range = 2.6–24.8). There was no association between UAs and cognitive abilities, and no consistent effect modification by %MMA. UAs was associated inversely with concept formation, and positively with cognitive efficiency and numbers reversed subtest in the lowest folate intake tertile; UAs was also positively associated with sound integration in the second tertile and concept formation in the highest tertile of folate intake. There was no consistent pattern of effect modification by %MMA or folate intake. Conclusion There was no association between low-level As exposure and general cognitive abilities.

Objectives Millions of children globally, including the U.S., are exposed to low levels of arsenic from water and food. Arsenic is a known neurotoxicant at high levels but its effects at lower exposure levels are understudied. Arsenic methylation capacity, influenced by B-vitamin intake and status, potentially influences arsenic toxicity. In a cross-secitonal study of 5–8 year-old children from Montevideo, we assessed the relationship between urinary arsenic (U–As) and academic achievement, and tested for effect modification by B-vitamin intake, status, and arsenic methylation capacity. Methods Broad math and reading scores were calculated based on six subtests (calculation, math facts fluency, applied problems, sentence reading fluency, letter word identification, passage comprehension) from the Woodcock-Munoz Achievement Battery. B-vitamin intake was assessed from two non-consecutive 24-h dietary recalls, serum folate and vitamin B-12 levels were measured in a subset of participants. Arsenic methylation capacity was measured as the proportion of urinary monomethylarsonic acid (%MMA). Multiple imputation using chained equations was conducted to account for missing covariate and exposure data. Ordinal regressions assessed associations between U–As and achievement score tertiles in the complete case and imputed samples. A “B-vitamin index” was calculated using principal component analysis. Interactions by urinary %MMA and the B-vitamin index were assessed. Results Median specific gravity adjusted U–As was 11.7 μg/L (range: 2.6, 50.1). We found no association between U–As and broad math and reading scores, nor effect modification by %MMA or B-vitamins. Conclusion At low-levels of exposure, U–As does not appear to affect children's academic achievement.

Arsenic exposure in children is a public health concern but is understudied in relation to the predictors, and effects of low-level exposure. We examined the extent and dietary predictors of exposure to inorganic arsenic in 5–8 year old children from Montevideo, Uruguay. Children were recruited at school; 357 were enrolled, 328 collected morning urine samples, and 317 had two 24-hour dietary recalls. Urinary arsenic metabolites, i.e. inorganic arsenic (iAs), methylarsonic acid (MMA), and dimethylarsinic acid (DMA), were measured using high-performance liquid chromatography with hydride generation and inductively coupled plasma mass spectrometry (HPLC-HG-ICP-MS), and the sum concentration (U-As) used for exposure assessment. Proportions of arsenic metabolites (%iAs, %MMA and %DMA) in urine were modelled in OLS regressions as functions of food groups, dietary patterns, nutrient intake, and nutritional status. Exposure to arsenic was low (median U-As: 9.9 µg/L) and household water (water As: median 0.45 µg/L) was not a major contributor to exposure. Children with higher consumption of rice had higher U-As but lower %iAs, %MMA, and higher %DMA. Children with higher meat consumption had lower %iAs and higher %DMA. Higher scores on ”nutrient dense” dietary pattern were related to lower %iAs and %MMA, and higher %DMA. Higher intake of dietary folate was associated with lower %MMA and higher %DMA. Overweight children had lower %MMA and higher %DMA than normal-weight children. In summary, rice was an important predictor of exposure to inorganic arsenic and DMA. Higher meat and folate consumption, diet rich in green leafy and red-orange vegetables and eggs, and higher BMI contributed to higher arsenic methylation capacity.

Background In the human body, inorganic arsenic (iAs) is methylated via the one-carbon cycle to form monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA). Lower proportions of iAs and MMA, and higher proportions of DMA in urine indicate efficient methylation; formation of DMA is thought to detoxify iAs and MMA. Studies on folate, vitamin B-12 and iAs methylation yield mixed findings, depending on whether folate and vitamin B-12 were assessed from diet, supplements, or using a blood biomarker. Objective First, to compare the associations of serum concentrations and estimated intake of folate and vitamin B-12 with indicators of iAs methylation. Second, to highlight the implications of these different B-vitamin assessment techniques on the emerging evidence of the impact of dietary modifications on iAs methylation. Methods The study was conducted among ~7-year-old children from Montevideo, Uruguay. Serum folate and vitamin B-12 levels were measured on the Horiba ABX Pentra 400 analyzer; urinary arsenic was measured using High-Performance Liquid Chromatography on-line with Inductively Coupled Plasma Mass Spectrometry. Dietary intakes were assessed using the average of two 24-h dietary recalls. Linear regressions assessed the associations of serum levels, and dietary intakes of folate (n = 237) and vitamin B-12 (n = 217) with indicators of iAs methylation. Models were adjusted for age, sex, body mass index, total urinary arsenic, and rice intake. Results Serum folate and vitamin B-12 levels were above the adequacy threshold for 99% of the participants. No associations were observed between serum folate, serum vitamin B-12, or vitamin B-12 intake and iAs methylation. Folate intake was inversely associated with urinary %MMA [β (95% confidence interval): −1.04 (−1.89, −0.18)]. Conclusion Additional studies on the role of B-vitamins in iAs methylation are needed to develop a deeper understanding of the implications of assessing folate and vitamin B-12 intake compared to the use of biomarkers. Where possible, both methods should be employed because they reflect different exposure windows and inherent measurement error, and if used individually, will likely continue to contribute to lack of consensus.

The negative effect of lead exposure on children&rsquo, s intelligence is well-documented. Less is known about the impact of lead on the use of executive functions to self-regulate behavior. We measured blood lead level (BLL) in a sample of first grade children from Montevideo, Uruguay (n = 206, age 6.7 &plusmn, 0.5 years, 59.7% boys). Behavior was assessed with teacher versions of the Conners Rating Scale (CRS) and the Behavior Rating Inventory of Executive Functions (BRIEF). Mean BLL was 4.2 &plusmn, 2.1 &mu, g/dL, 10% had mild-to-severe ratings of Attentional Deficit with Hyperactivity Disorder (ADHD) (T score &gt, 65). In negative binomial regression, BLL was not associated with CRS sub-scales, but was associated with a poorer ability to inhibit inappropriate behaviors, prevalence ratio (PR) [95% CI]: 1.01 [1.00, 1.03] as measured by the BRIEF. In covariate-adjusted models, the association with BLL was attenuated. When stratified by sex, the covariate-adjusted association between BLL, hyperactivity, poorer inhitibion, emotional control, and behavioral regulation was marginally significant for girls but not boys. In summary, among children with low lead-exposure, we found some, but nonetheless modest, evidence of a relationship between higher BLL and child behavior. If confirmed by larger studies and other objective measures of behavior, such links could have implications for learning and social interaction, particularly among girls.

Oxidative stress (OS) is a potential molecular mechanism for lead-induced toxicities, yet, we have limited understanding of the relation between low-level lead (Pb) exposure and OS, especially in children. This cross-sectional study examines the association between blood lead level (BLL) and two OS markers—urinary F2-8α isoprostane or isoprostane (a marker of lipid peroxidation) and 8-hydroxy-2-deoxy-Guanosine or 8-OH-dG (a marker of DNA damage) in 211 children, aged 5–8 years, from Montevideo, Uruguay. The role of dietary intakes of vitamin C and zinc in modifying the relation between BLL and OS was also examined. The mean (SD) BLL of the study children was 4.7 (2.2) μg/dL, with 30.2% children having BLL ≥5 μg/dL, the current reference level set by the US Centre for Disease Control for identifying, monitoring and management of children with elevated BLL. In covariate-adjusted analysis, there was a weak positive association between BLL and urinary isoprostane (adjusted for specific gravity) [β = 0.09, p< 0.1]. No association was found between children’s BLL and urinary 8-OH-dG. Interactions between dietary intakes of vitamin C or zinc and BLL on OS biomarkers were not consistent. However, when BLL and vitamin C or BLL and zinc were modeled together, BLL was independently associated with isoprostane concentration [β = 0.10, p< 0.05] but vitamin C or zinc intake was not. These findings suggest that there may be a potential adverse effect of BLL on OS in children with low-level Pb exposure. There is a need to study the effects of Pb on other OS measures, as well as the role of OS in mediating low-level Pb toxicity on functional outcomes.

While it is known that toxic metals contribute individually to child cognitive and behavioral deficits, we still know little about the effects of exposure to multiple metals, particularly when exposures are low. We studied the association between children’s blood lead and hair arsenic, cadmium, and manganese and their performance on the Bayley Scales of Infant Development III. Ninety-two preschool children (age 13–42 months) from Montevideo, Uruguay, provided a hair sample and 78 had a blood lead level (BLL) measurement. Using latent class analysis (LCA), we identified four groups of exposure based on metal concentrations: (1) low metals, (2) low-to-moderate metals, (3) high lead and cadmium, and (4) high metals. Using the four-group exposure variable as the main predictor, and fitting raw scores on the cognitive, receptive vocabulary, and expressive vocabulary scales as dependent variables, both complete-case and multiple imputation (MI) analyses were conducted. We found no association between multiple-metal exposures and neurodevelopment in covariate-adjusted models. This study demonstrates the use of LCA together with MI to determine patterns of exposure to multiple toxic metals and relate these to child neurodevelopment. However, because the overall study population was small, other studies with larger sample sizes are needed to investigate these associations.

Lead exposure remains an important public health problem. Contaminated foods may act as a source of lead exposure, while certain nutrients may reduce lead absorption. We examined the cross-sectional associations of dietary patterns and the intake of several nutrients and foods with blood (Pb-B) and urinary (Pb-U) lead concentrations in children (5–8y) from Montevideo, Uruguay. From two 24-hour recalls completed by caregivers, we derived the mean daily intake of select nutrients and food groups (dairy, milk, fruit, root vegetables, foods rich in heme and non-heme iron), as well as “nutrient dense” and “processed” food patterns. Pb-B (n=315) was measured using atomic absorption spectrometry; Pb-U (n=321) using ICP-MS. Pb-U was adjusted for specific gravity and log-transformed to approximate a normal distribution. Iron deficiency (ID) and dietary variables were tested as predictors of Pb-B and log-Pb-U in covariate-adjusted regressions. Median [5%, 95%] Pb-B and Pb-U were 3.8 [0.8–7.8] μg/dL and 1.9 [0.6–5.1] μg/L, respectively; ~25% of Pb-B above current U.S. CDC reference concentration of 5μg/dL. ID was associated with 0.75μg/dL higher Pb-B, compared to non-ID (p

Environmental manganese (Mn) exposure in childhood has been associated with developmental deficits. This study investigated associations between low-level Mn exposure and developmental scores in children aged 14-45 months. Children's hair samples (n = 60) were analyzed for Mn and lead (Pb) using inductively coupled plasma mass spectrometry (ICP-MS). Children were assessed with the Bayley Scales of Infant Development III (BSID). Mean hair Mn and Pb concentrations were 0.98 ± 0.74 and 10.1 ± 10.5 μg/g, respectively. Unadjusted inverse associations were seen between Mn and BSID subscales, with girls having lower scores related to Mn than boys. No significant associations remained in covariate-adjusted models, although when stratified by sex boys had a positive association between hair Mn levels and language scores. This study does not show clear evidence of an association between hair Mn concentrations and children's developmental scores in a region of low-level Mn exposure.

The extent of children's exposure to multiple toxic metals is not well described in many developing countries. We examined metal exposures in young children (6-37 months) from Montevideo, Uruguay and their mothers (15-47 years) participating in a community-based study. Hair samples collected from 180 children and their mothers were analyzed for: lead (Pb), cadmium (Cd), manganese (Mn), and arsenic (As) concentration using inductively coupled plasma-mass spectrometry (ICP-MS). Median metal levels (microg/g) were: Pb 13.69, Mn 1.45, Cd 0.17, and As 0.09 for children and Pb 4.27, Mn 1.42, Cd 0.08, and As 0.02 for mothers. Of the child and maternal samples, 1.7% and 2.9% were below the limit of detection (LOD) for Cd, and 21.3% and 38.5% were below the LOD for As, respectively. Correlations between maternal and child levels ranged 0.38-0.55 (p

We investigated the prevalence and predictors of depression in low-income mothers (n = 99) of young children from Uruguay. We administered the Beck Depression Scale (BDI) and the Parenting Stress Index (PSI), and asked who is responsible for the main tasks of parenting and household care. We found a high prevalence of moderate-to-severe depression (BDI >19 points, 31.3%), with women with t scores > 90 on the PSI being seven times more likely to experience moderate-to-severe depressive symptoms than women with lower PSI scores (p

Biological and psychosocial factors affect child development and behavior. Whereas biological underpinnings behind the neurotoxic effects of lead are studied extensively, the effects of psychosocial factors contributing to poor behavioral outcomes in lead-exposed children are not well understood. Parental attributes and practices may moderate or mediate the effects of lead on children's behavioral outcomes. We investigated the hypothesis that maternal and child lead and hemoglobin levels are associated with maternal perceptions of their parenting. Specifically, we hypothesized that children with higher blood lead (BLL) and lower hemoglobin concentrations would be associated with poorer maternal self-assessments of their parenting skills or the mother-child relationship. Children aged 13-55 months and their mothers (n=109) were recruited from among the participants of a previous lead and anemia screening study and from preschools in Montevideo, Uruguay. The mother-child pair attended two study visits: one to collect biological samples and answer demographic and child questionnaires, including statements regarding parenting; and a second to evaluate maternal IQ, depression and stress, and child development. Of the children, 51.6% had blood lead concentrations (BLLs) ≥ 5 μg/dL, 18.0% had anemia, and 8% had both conditions. Among mothers, 48.4% had BLLs ≥ 5 μg/dL, 16.0% had anemia, and 11% had both. BLLs ≥ 5 μg/dL in mother or child were associated with lower maternal perceptions of being skilled at discipline (p

Elevated blood lead levels (BPbs) have been identified in Uruguayan children in the La Teja neighborhood of Montevideo, but the extent of lead exposure in other city areas is unknown. Sources and predictors of exposure also remain understudied in this population. In 2007, the authors screened lead and hemoglobin levels in capillary blood of 222 preschool children from several areas of Montevideo, Uruguay, and identified predictors of elevated BPbs. Mean BPb was 9.0 +/- 6.0 microg/dL and 32.9% of children had levels >or= 10microg/dL. Mean hemoglobin level was 10.5 +/- 1.5 g/dL, with 44.1% having levels