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Wallace ER, Buth E, Szpiro AA, Ni Y, Loftus CT, Masterson E, Day DB, Sun BZ, Sullivan A, Barrett E, Nguyen RH, Robinson M, Kannan K, Mason A, Sathyanarayana S, LeWinn KZ, Bush NR, Karr CJ. Prenatal exposure to polycyclic aromatic hydrocarbons is not associated with behavior problems in preschool and early school-aged children: A prospective multi-cohort study. ENVIRONMENTAL RESEARCH 2023; 216:114759. [PMID: 36370819 PMCID: PMC9817935 DOI: 10.1016/j.envres.2022.114759] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 11/02/2022] [Accepted: 11/05/2022] [Indexed: 05/31/2023]
Abstract
BACKGROUND Epidemiological study findings are inconsistent regarding associations between prenatal polycyclic aromatic hydrocarbon (PAH) exposures and childhood behavior. This study examined associations of prenatal PAH exposure with behavior at age 4-6 years in a large, diverse, multi-region prospective cohort. Secondary aims included examination of PAH mixtures and effect modification by child sex, breastfeeding, and child neighborhood opportunity. METHODS The ECHO PATHWAYS Consortium pooled 1118 mother-child dyads from three prospective pregnancy cohorts in six U.S. cities. Seven PAH metabolites were measured in prenatal urine. Child behavior was assessed at age 4-6 using the Total Problems score from the Child Behavior Checklist (CBCL). Neighborhood opportunity was assessed using the socioeconomic and educational scales of the Child Opportunity Index. Multivariable linear regression was used to estimate associations per 2-fold increase in each PAH metabolite, adjusted for demographic, prenatal, and maternal factors and using interaction terms for effect modifiers. Associations with PAH mixtures were estimated using Weighted Quantile Sum Regression (WQSR). RESULTS The sample was racially and sociodemographically diverse (38% Black, 49% White, 7% Other; household-adjusted income range $2651-$221,102). In fully adjusted models, each 2-fold increase in 2-hydroxynaphthalene was associated with a lower Total Problems score, contrary to hypotheses (b = -0.80, 95% CI = -1.51, -0.08). Associations were notable in boys (b = -1.10, 95% CI = -2.11, -0.08) and among children breastfed 6+ months (b = -1.31, 95% CI = -2.25, -0.37), although there was no statistically significant evidence for interaction by child sex, breastfeeding, or neighborhood child opportunity. Associations were null for other PAH metabolites; there was no evidence of associations with PAH mixtures from WQSR. CONCLUSION In this large, well-characterized, prospective study of mother-child pairs, prenatal PAH exposure was not associated with child behavior problems. Future studies characterizing the magnitude of prenatal PAH exposure and studies in older childhood are needed.
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Affiliation(s)
- Erin R Wallace
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA.
| | - Erin Buth
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA
| | - Adam A Szpiro
- Department of Biostatistics, School of Public Health, University of Washington, Seattle, WA, USA
| | - Yu Ni
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA
| | - Christine T Loftus
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA
| | - Erin Masterson
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA
| | - Drew B Day
- Seattle Children's Research Institute, Seattle, WA, USA
| | - Bob Z Sun
- Department of Pediatrics, School of Medicine, University of Washington, Seattle, WA, USA
| | - Alexis Sullivan
- Department of Psychiatry and Behavioral Sciences, School of Medicine, University of California, San Francisco, San Francisco, California, USA
| | - Emily Barrett
- Department of Biostatistics and Epidemiology, Environmental and Occupational Health Sciences Institute, School of Public Health, Rutgers University, Piscataway, NJ, USA
| | - Ruby Hn Nguyen
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN, USA
| | - Morgan Robinson
- Department of Pediatrics and Department of Environmental Medicine, New York University School of Medicine, New York, NY, 10016, USA
| | - Kurunthachalam Kannan
- Department of Pediatrics and Department of Environmental Medicine, New York University School of Medicine, New York, NY, 10016, USA
| | - Alex Mason
- Department of Preventive Medicine, University of Tennessee Health Sciences Center, Memphis, TN, USA
| | - Sheela Sathyanarayana
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA; Seattle Children's Research Institute, Seattle, WA, USA; Department of Pediatrics, School of Medicine, University of Washington, Seattle, WA, USA
| | - Kaja Z LeWinn
- Department of Psychiatry and Behavioral Sciences, School of Medicine, University of California, San Francisco, San Francisco, California, USA
| | - Nicole R Bush
- Department of Psychiatry and Behavioral Sciences, School of Medicine, University of California, San Francisco, San Francisco, California, USA; Department of Pediatrics, School of Medicine, University of California, San Francisco, San Francisco, California, USA
| | - Catherine J Karr
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA; Department of Pediatrics, School of Medicine, University of Washington, Seattle, WA, USA; Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA, USA
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de Araújo ÉJF, de Almeida AAC, Silva OA, da Costa IHF, Rezende-Júnior LM, Lima FDCA, Cavalheiro AJ, Pessoa C, de Moraes MO, Ferreira PMP. Behavioral effects induced by antitumor cleronade diterpenes from Casearia sylvestris and in silico interactions with neuron receptors. JOURNAL OF ETHNOPHARMACOLOGY 2017; 198:460-467. [PMID: 28077331 DOI: 10.1016/j.jep.2017.01.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 01/04/2017] [Accepted: 01/06/2017] [Indexed: 06/06/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Casearia sylvestris is a medicinal plant traditionally used to treat snakebites, wounds, inflammation and gastric ulcers and scientific supports for have demonstrated its antitumor, antihyperlipidemic and antiparasitic properties. AIM OF THE STUDY To assess the effects of a fraction with casearins (FC) on adult mice using classical experimental models of animal behavior and theoretical calculations to verify the interaction of Casearin X (Cas X) with neuron receptors. MATERIALS AND METHODS Animals divided in 6 groups (n=9/group) were intraperitoneally treated with vehicle (DMSO 4%), FC (2.5, 5, 10 and 25mg/kg/day) and diazepam (2mg/kg) for 7 days. Thirty minutes after the last dose of treatment, acute toxicity and behavioral experiments were performed. RESULTS The highest dose of FC (25mg/kg/day) caused diarrhea, weight loss and death of one animal. Elevated plus maze test showed that lower doses [2.5mg/kg/day (36.4±5.1s) and 5mg/kg/day (43.9±6.2s)] increased the time spent in open arms (TSOA). Open field test revealed reduction in the number of crossings (54.9%, 51.1%, 48% and 67.7% for 2.5, 5, 10 and 25mg/kg/day, respectively) in all doses of FC studied and decrease of rearings at 25mg/kg/day (p<0.05). Computational calculations showed that the inhibition constant (Ki) for the Cas X-D1 complex is up to 1000-fold more favourable than the Cas X-GABAA complex. All ∆G° values obtained for Cas X-D1 complexes were more negative than those seen with Cas X-GABAA complexes. CONCLUSIONS Findings indicate a probable anxiolytic action of the FC since it reduces the number of crossings and rearings and prolonged the time spent in open arms, without sedative and myorelaxant effects, probably due to the interaction of Cas X with dopaminergic system.
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Affiliation(s)
- Éverton José Ferreira de Araújo
- Postgraduate Program in Pharmaceutical Sciences, Federal University of Piauí, Teresina, Brazil; Department of Pharmacy, Federal University of Piauí, Teresina, Brazil
| | | | - Oskar Almeida Silva
- Postgraduate Program in Biotechnology (RENORBIO), Federal University of Piauí, Teresina, Brazil
| | | | | | - Francisco das Chagas Alves Lima
- Postgraduate Program in Biotechnology (RENORBIO), Federal University of Piauí, Teresina, Brazil; Quantum Computational Chemistry Laboratory, Department of Chemistry, State University of Piauí, Teresina, Piauí, Brazil
| | - Alberto José Cavalheiro
- Department of Organic Chemisty, Chemistry Institute, State University of São Paulo Júlio de Mesquita Filho, Araraquara, Brazil
| | - Cláudia Pessoa
- Department of Physiology and Pharmacology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Manoel Odorico de Moraes
- Department of Physiology and Pharmacology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Paulo Michel Pinheiro Ferreira
- Postgraduate Program in Pharmaceutical Sciences, Federal University of Piauí, Teresina, Brazil; Postgraduate Program in Biotechnology (RENORBIO), Federal University of Piauí, Teresina, Brazil; Department of Biophysics and Physiology, Laboratory of Experimental Cancerology, Federal University of Piauí, Teresina, Brazil.
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Soeiro AC, Gouvêa TS, Moreira EG. Behavioral effects induced by subchronic exposure to Pb and their reversion are concentration and gender dependent. Hum Exp Toxicol 2016; 26:733-9. [DOI: 10.1177/0960327107083016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Lead (Pb) seems to be involved in the etiology of psychological pathologies. This study investigated the effects of subchronic Pb exposure from weaning to adulthood on anxiety, depression and aggressiveness in male and female Swiss mice. Moreover, the reversibility of the effects was evaluated retesting the animals 30 days after the end of exposure. Swiss male and female mice (21 days) were exposed to 0, 50, 100 or 500 ppm of Pb, as Pb acetate, in drinking water for 70 days and were submitted to the forced swimming, tail suspension, elevated plus-maze or intruder—resident tests. Pb exposure to 50 and 500 ppm induced anti-depressant-like effect in both males and females, whereas exposure to 500 ppm induced anxiogenic effect only in males. Interruption of exposure was able to reverse the behavioral alterations in females, but not in males exposed to the highest concentration (500 ppm). Our results suggest that behavioral effects induced by subchronic exposure to Pb from weaning to adulthood and their reversion are concentration and gender dependent. [Human & Experimental Toxicology] (2007) 26, 733—739
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Affiliation(s)
- Aline C. Soeiro
- Department of Physiological Sciences, State University of Londrina, Londrina, PR, Brazil
| | - Thiago S. Gouvêa
- Department of Physiological Sciences, State University of Londrina, Londrina, PR, Brazil
| | - Estefânia G. Moreira
- Department of Physiological Sciences, State University of Londrina, Londrina, PR, Brazil,
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Stroustrup A, Hsu HH, Svensson K, Schnaas L, Cantoral A, Solano González M, Torres-Calapiz M, Amarasiriwardena C, Bellinger DC, Coull BA, Téllez-Rojo MM, Wright RO, Wright RJ. Toddler temperament and prenatal exposure to lead and maternal depression. Environ Health 2016; 15:71. [PMID: 27312840 PMCID: PMC4910201 DOI: 10.1186/s12940-016-0147-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 05/30/2016] [Indexed: 05/21/2023]
Abstract
BACKGROUND Temperament is a psychological construct that reflects both personality and an infant's reaction to social stimuli. It can be assessed early in life and is stable over time Temperament predicts many later life behaviors and illnesses, including impulsivity, emotional regulation and obesity. Early life exposure to neurotoxicants often results in developmental deficits in attention, social function, and IQ, but environmental predictors of infant temperament are largely unknown. We propose that prenatal exposure to both chemical and non-chemical environmental toxicants impacts the development of temperament, which can itself be used as a marker of risk for maladaptive neurobehavior in later life. In this study, we assessed associations among prenatal and early life exposure to lead, mercury, poverty, maternal depression and toddler temperament. METHODS A prospective cohort of women living in the Mexico City area were followed longitudinally beginning in the second trimester of pregnancy. Prenatal exposure to lead (blood, bone), mercury, and maternal depression were assessed repeatedly and the Toddler Temperament Scale (TTS) was completed when the child was 24 months old. The association between each measure of prenatal exposure and performance on individual TTS subscales was evaluated by multivariable linear regression. Latent profile analysis was used to classify subjects by TTS performance. Multinomial regression models were used to estimate the prospective association between prenatal exposures and TTS performance. RESULTS 500 mother-child pairs completed the TTS and had complete data on exposures and covariates. Three latent profiles were identified and categorized as predominantly difficult, intermediate, or easy temperament. Prenatal exposure to maternal depression predicted increasing probability of difficult toddler temperament. Maternal bone lead, a marker of cumulative exposure, also predicted difficult temperament. Prenatal lead exposure modified this association, suggesting that joint exposure in pregnancy to both was most toxic. CONCLUSIONS Maternal depression predicts difficult temperament and concurrent prenatal exposure to maternal depression and lead predicts a more difficult temperament phenotype in 2 year olds. The role of temperament as an intermediate variable in the path from prenatal exposures to neurobehavioral deficits and other health effects deserves further study.
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Affiliation(s)
- Annemarie Stroustrup
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Division of Newborn Medicine, Department of Pediatrics, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1508, New York, NY, 10029, USA.
| | - Hsiao-Hsien Hsu
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Katherine Svensson
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Lourdes Schnaas
- Department of Developmental Neurobiology, National Institute of Perinatology, Mexico City, Mexico
| | - Alejandra Cantoral
- Center for Nutrition and Health Research, National Institute of Public Health, Morelos, Mexico
| | - Maritsa Solano González
- Center for Nutrition and Health Research, National Institute of Public Health, Morelos, Mexico
| | - Mariana Torres-Calapiz
- Department of Developmental Neurobiology, National Institute of Perinatology, Mexico City, Mexico
| | - Chitra Amarasiriwardena
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - David C Bellinger
- Departments of Neurology and Psychiatry, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA
| | - Brent A Coull
- Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA
- Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA
| | - Martha M Téllez-Rojo
- Center for Nutrition and Health Research, National Institute of Public Health, Morelos, Mexico
| | - Robert O Wright
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Rosalind J Wright
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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Avan BI, Raza SA, Kirkwood BR. A community-based study of early childhood sensory stimulation in home environment associated with growth and psychomotor development in Pakistan. Int J Public Health 2013; 59:779-88. [PMID: 24212327 DOI: 10.1007/s00038-013-0525-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2012] [Revised: 09/05/2013] [Accepted: 10/21/2013] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVES Sensory stimulation (SS) is a non-nutritional modifiable risk factor for early childhood development. We assessed SS in home environment and examined its influence on physical growth and psychomotor development (PD). METHODS A cross-sectional study was conducted in 26 communities in Pakistan among children aged <3 (n = 1,219). They were assessed at home visits using (1) Bayley's Infant Developmental Scale for PD, (2) home observation for measurement of the environment inventory for SS, (3) anthropometry and (4) socio-economic questionnaire. RESULTS In rural homes, SS provided was lower as compared to urban counterparts (Adj mean diff: 4.47, 95 % CI 3.78, 5.16) and showed an association with stunting (Adj mean diff: -1.30, 95 % CI -1.93, -0.66), and underweight (Adj mean diff: -1.04, 95 % CI -1.71, -0.38) not explained by type of neighbourhood or socio-economic status. SS was associated with PD more than combined contribution of socio-economic status and rural-urban factors (Adj mean diff: 0.47, 95 % CI 0.30, 0.63). CONCLUSIONS SS in rural homes may be a significant factor influencing the child development. There is a need to corroborate these results by additional research for integration in health policy initiatives.
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Affiliation(s)
- Bilal Iqbal Avan
- Informed Decisions for Actions in Maternal and Newborn Health (IDEAS), Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK,
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Ciesielski T, Weuve J, Bellinger DC, Schwartz J, Lanphear B, Wright RO. Cadmium exposure and neurodevelopmental outcomes in U.S. children. ENVIRONMENTAL HEALTH PERSPECTIVES 2012; 120:758-63. [PMID: 22289429 PMCID: PMC3346779 DOI: 10.1289/ehp.1104152] [Citation(s) in RCA: 171] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 01/17/2012] [Indexed: 05/19/2023]
Abstract
BACKGROUND Low-level environmental cadmium exposure in children may be associated with adverse neurodevelopmental outcomes. OBJECTIVE Our aim was to evaluate associations between urinary cadmium concentration and reported learning disability (LD), special education utilization, and attention deficit hyperactivity disorder (ADHD) in U.S. children using National Health and Nutrition Examination Survey (NHANES) data. METHODS We analyzed data from a subset of participants in NHANES (1999-2004) who were 6-15 years of age and had spot urine samples analyzed for cadmium. Outcomes were assessed by parent or proxy-respondent report. We fit multivariable-adjusted logistic regression models to estimate associations between urinary cadmium and the outcomes. RESULTS When we compared children in the highest quartile of urinary cadmium with those in the lowest quartile, odds ratios adjusted for several potential confounders were 3.21 [95% confidence interval (CI): 1.43, 7.17] for LD, 3.00 (95% CI: 1.12, 8.01) for special education, and 0.67 (95% CI: 0.28, 1.61) for ADHD. There were no significant interactions with sex, but associations with LD and special education were somewhat stronger in males, and the trend in the ADHD analysis was only evident among those with blood lead levels above the median. CONCLUSIONS These findings suggest that children who have higher urinary cadmium concentrations may have increased risk of both LD and special education. Importantly, we observed these associations at exposure levels that were previously considered to be without adverse effects, and these levels are common among U.S. children.
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Affiliation(s)
- Timothy Ciesielski
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA.
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Roy A, Bellinger D, Hu H, Schwartz J, Ettinger AS, Wright RO, Bouchard M, Palaniappan K, Balakrishnan K. Lead exposure and behavior among young children in Chennai, India. ENVIRONMENTAL HEALTH PERSPECTIVES 2009; 117:1607-11. [PMID: 20019913 PMCID: PMC2790517 DOI: 10.1289/ehp.0900625] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2009] [Accepted: 06/26/2009] [Indexed: 05/21/2023]
Abstract
BACKGROUND Lead exposure has long been associated with deficits in IQ among children. However, few studies have assessed the impact of lead on specific domains of behavior and cognition. OBJECTIVE We evaluated the associations between lead and different domains of neurobehavior and their relative sensitivity to lead. METHODS We determined blood lead levels using a LeadCare instrument in 756 children 3-7 years of age attending pre- and elementary schools in Chennai, India. Anxiety, social problems, inattention, hyperactivity, and attention deficit hyperactivity disorder (ADHD), as well as executive function were assessed in children by their schoolteachers using Conners' Teacher Rating Scales-39, Conners' ADHD/Diagnostic and Statistical Manual for Mental Disorders, 4th Edition Scales (CADS), and the Behavior Rating Inventory of Executive Function questionnaires, with higher scores denoting worse behavior. Analyses were carried out using multivariate generalized estimating equations with comparisons of outcome Z-scores to assess the relative strengths of the associations between log-blood lead and the different domains of behavior. RESULTS Mean blood lead level was 11.4 +/- 5.3 microg/dL. Blood lead was associated with higher anxiety (beta = 0.27, p = 0.01), social problems (beta = 0.20, p = 0.02), and higher scores in the ADHD index (beta = 0.17; p = 0.05). The effect estimate was highest for global executive function (beta = 0.42; p< 0.001). CONCLUSIONS Higher blood lead levels in this population of young children is associated with increased risk of neurobehavioral deficits and ADHD, with executive function and attention being particularly vulnerable domains to the effects of lead.
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Affiliation(s)
- Ananya Roy
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA.
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Weiss B, Cory-Slechta D, Gilbert SG, Mergler D, Miller E, Miller C, Newland MC, Rice D, Schettler T. The new tapestry of risk assessment. Neurotoxicology 2008; 29:883-90. [PMID: 18501430 DOI: 10.1016/j.neuro.2008.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2008] [Revised: 04/03/2008] [Accepted: 04/04/2008] [Indexed: 10/22/2022]
Abstract
Neurotoxicology is entering a new phase in how it views and practices risk assessment. Perhaps more than any of the other disciplines that comprise the science of toxicology, it has been compelled to consider a daunting array of factors other than those directly coupled to chemical and dose, and the age and sex of the subject population. In epidemiological investigations, researchers are increasingly cognizant of the problems introduced by allegedly controlling for variables classified as confounders or covariates. In essence, they reason, the consequence is blurring or even concealing interactions of exposure with modifiers such as the individual's social ecology. Other researchers question the traditional practice of relying on values such as NOAELs when they are abstracted from a biological entity that in reality represents a multiplicity of intertwined systems. Although neurotoxicologists have come to recognize the complexities of assessing risk in all its dimensions, they still face the challenge of communicating this view to the health professions at large.
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Affiliation(s)
- Bernard Weiss
- Department of Environmental Medicine and Environmental Health Sciences Center, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
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Environmental injustice: childhood lead poisoning, teen pregnancy, and tobacco. J Adolesc Health 2008; 42:43-9. [PMID: 18155029 DOI: 10.1016/j.jadohealth.2007.06.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2007] [Revised: 06/14/2007] [Accepted: 06/28/2007] [Indexed: 11/21/2022]
Abstract
PURPOSE This study investigates the persistent relationships between childhood lead exposure, repeat teen pregnancy, and tobacco use in a sample of teenage females in Syracuse, NY. METHODS We analyzed the association of childhood lead poisoning with repeat pregnancy and tobacco use among 536 teens (aged 15-19 years) in Syracuse, NY, who received services at Syracuse Healthy Start between 1998 and 2002. RESULTS The mothers' childhood lead exposure, controlling for race, age, and Medicaid status, was associated with repeat teen pregnancy and tobacco use. CONCLUSION Long-term negative health outcomes associated with childhood lead exposure should not be underestimated. This study helps to shore up prior research that found lead poisoning to have a long-lasting impact on children's functioning and healthy development. Policy efforts focused on neighborhood development and health education continue to be sorely needed.
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Beaudin SA, Stangle DE, Smith DR, Levitsky DA, Strupp BJ. Succimer chelation normalizes reactivity to reward omission and errors in lead-exposed rats. Neurotoxicol Teratol 2007; 29:188-202. [PMID: 17196787 DOI: 10.1016/j.ntt.2006.11.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2006] [Revised: 10/08/2006] [Accepted: 11/12/2006] [Indexed: 11/23/2022]
Abstract
This study evaluated the efficacy of a 3-week course of succimer treatment to alleviate behavioral deficits in rats exposed to lead (Pb) for the first 4 weeks of life. A 3 x 2 factorial design was used: three levels of lead exposure (No Pb, Moderate, and High Pb) and two levels of chelation (succimer or vehicle). Behavioral testing was conducted following chelation therapy, from 2 to 9 months of age; this report presents the results of two of the administered tasks: (1) a conditional olfactory discrimination task (baseline task), and (2) a conditional olfactory discrimination task with periodic reward omission on some correct trials (RO task). In the RO task, the performance disruption produced by committing an error on the previous trial was significantly greater for both unchelated lead-exposed groups than for controls. The High Pb rats were also more sensitive to reward omission than controls, providing converging evidence for impaired regulation of arousal or emotion. Importantly, succimer treatment was effective in normalizing the heightened reactivity of the lead-exposed animals to both errors and reward omission. In addition, non-lead-exposed rats that were treated with succimer tended to be more affected by a prior error than controls in their latency to respond on post-error trials. In sum, these findings provide new evidence that succimer chelation can significantly lessen the lasting neurobehavioral dysfunction produced by early lead exposure, but also suggest that there may be risks of administering the drug to individuals without elevated blood lead levels.
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Affiliation(s)
- Stéphane A Beaudin
- Division of Nutritional Sciences, Cornell University, Savage Hall, Ithaca, NY 14853, USA
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Weiss B, Bellinger DC. Social ecology of children's vulnerability to environmental pollutants. ENVIRONMENTAL HEALTH PERSPECTIVES 2006; 114:1479-85. [PMID: 17035129 PMCID: PMC1626436 DOI: 10.1289/ehp.9101] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
BACKGROUND The outcomes of exposure to neurotoxic chemicals early in life depend on the properties of both the chemical and the host's environment. When our questions focus on the toxicant, the environmental properties tend to be regarded as marginal and designated as covariates or confounders. Such approaches blur the reality of how the early environment establishes enduring biologic substrates. OBJECTIVES In this commentary, we describe another perspective, based on decades of biopsychological research on animals, that shows how the early, even prenatal, environment creates permanent changes in brain structure and chemistry and behavior. Aspects of the early environment-encompassing enrichment, deprivation, and maternal and neonatal stress-all help determine the functional responses later in life that derive from the biologic substrate imparted by that environment. Their effects then become biologically embedded. Human data, particularly those connected to economically disadvantaged populations, yield equivalent conclusions. DISCUSSION In this commentary, we argue that treating such environmental conditions as confounders is equivalent to defining genetic differences as confounders, a tactic that laboratory research, such as that based on transgenic manipulations, clearly rejects. The implications extend from laboratory experiments that, implicitly, assume that the early environment can be standardized to risk assessments based on epidemiologic investigations. CONCLUSIONS The biologic properties implanted by the early social environment should be regarded as crucial elements of the translation from laboratory research to human health and, in fact, should be incorporated into human health research. The methods for doing so are not clearly defined and present many challenges to investigators.
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Affiliation(s)
- Bernard Weiss
- Department of Environmental Medicine, Environmental Health Sciences Center, and Center for Reproductive Epidemiology, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642, USA.
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Fido A, Al-Saad S. Toxic trace elements in the hair of children with autism. AUTISM : THE INTERNATIONAL JOURNAL OF RESEARCH AND PRACTICE 2005; 9:290-8. [PMID: 15937043 DOI: 10.1177/1362361305053255] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Excess or deficiency of natural trace elements has been implicated in the etiology of autism. This study explores whether concentration levels of toxic metals in the hair of children with autism significantly differ from those of age- and sex-matched healthy controls. In-hair concentration levels of antimony, uranium, arsenic, beryllium, mercury, cadmium, lead and aluminum from 40 boys with autism and 40 healthy boys were determined by Perkin-Elmer mass spectrometry. The children with autism had significantly (p<0.001) higher in-hair concentration levels of lead, mercury and uranium. There was no significant difference between the two groups in the other five toxic elements. The ratio between nutritional elements and toxic metals among children with autism was within the normal range. The possible sources of the toxic metals are discussed. Such testing is informative but at present the practical implications in terms of diagnosis and clinical management are limited.
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Affiliation(s)
- Abdullahi Fido
- Department of Psychiatry, Faculty of Medecine, Kuwait University, Kuwait.
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Mink PJ, Goodman M, Barraj LM, Imrey H, Kelsh MA, Yager J. Evaluation of Uncontrolled Confounding in Studies of Environmental Exposures and Neurobehavioral Testing in Children. Epidemiology 2004; 15:385-93. [PMID: 15232397 DOI: 10.1097/01.ede.0000128402.86336.7e] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Neurobehavioral tests are commonly used in studies of children exposed to low-level environmental concentrations of compounds known to be neurotoxic at higher levels. However, uncontrolled or incomplete control for confounding makes interpretation of results problematic because effects of confounders are often stronger than the effects of primary interest. We examined a priori the potential impact of confounding in a hypothetical study evaluating the association of a potentially neurotoxic environmental exposure with neurobehavioral function in children. METHODS We used 2 outcome measures: the Bayley Scales of Infant Development Mental Development Index and the Stanford-Binet Intelligence Scale Composite Score. We selected 3 potential confounders: maternal intelligence, home environment, and socioeconomic status as measured by years of parental education. We conducted 3 sets of analyses measuring the effect of each of the 3 confounding factors alone, 2 confounders acting simultaneously, and all 3 confounders acting simultaneously. RESULTS Relatively small differences (0.5 standard deviations) in confounding variables between "exposed" and "unexposed" groups, if unmeasured and unaccounted for in the analysis, could produce spurious differences in cognitive test scores. The magnitude of this difference (3-10 points) has been suggested to have a meaningful impact in populations. The method of measuring confounders (eg, maternal intelligence) could also substantially affect the results. CONCLUSIONS It is important to carefully consider the impact of potential confounders during the planning stages of an observational study. Study-to-study differences in neurobehavioral outcomes with similar environmental exposures could be partially explained by differences in the adjustment for confounding variables.
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Abstract
Children differ from adults in the relative importance of lead sources and pathways, lead metabolism, and the toxicities expressed. The central nervous system effects of lead on children seem not to be reversible. Periods of enhanced vulnerability within childhood have not consistently been identified. The period of greatest vulnerability might be endpoint specific, perhaps accounting for the failure to identify a coherent “behavioral signature” for lead toxicity. The bases for the substantial individual variability in vulnerability to lead are uncertain, although they might include genetic polymorphisms and contextual factors. The current Centers for Disease Control and Prevention screening guideline of 10 μg/dL is a risk management tool and should not be interpreted as a threshold for toxicity. No threshold has been identified, and some data are consistent with effects well below 10. Historically, most studies have concentrated on neurocognitive effects of lead, but higher exposures have recently been associated with morbidities such as antisocial behavior and delinquency. Studies of lead toxicity in experimental animal models are critical to the interpretation of nonexperimental human studies, particularly in addressing the likelihood that associations observed in the latter studies can be attributed to residual confounding. Animal models are also helpful in investigating the behavioral and neurobiological mechanisms of the functional deficits observed in lead-exposed humans. Studies of adults who have been exposed to lead are of limited use in understanding childhood lead toxicity because developmental and acquired lead exposure differ in terms of the maturity of the organs affected, the presumed mechanisms of toxicity, and the forms in which toxicities are expressed.
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Affiliation(s)
- David C. Bellinger
- From the Children’s Hospital Boston, Harvard Medical School, Boston, Massachusetts
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Wachs TD. Expanding Our View of Context: The Bio-ecological Environment and Development. ADVANCES IN CHILD DEVELOPMENT AND BEHAVIOR 2004; 31:363-409. [PMID: 14528666 DOI: 10.1016/s0065-2407(03)31009-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Theodore D Wachs
- Department of Psychological Sciences, Purdue University, West Lafayette, Indiana 47907, USA
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Anger WK. Neurobehavioural tests and systems to assess neurotoxic exposures in the workplace and community. Occup Environ Med 2003; 60:531-8, 474. [PMID: 12819291 PMCID: PMC1740574 DOI: 10.1136/oem.60.7.531] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Morgan RE, Garavan H, Smith EG, Driscoll LL, Levitsky DA, Strupp BJ. Early lead exposure produces lasting changes in sustained attention, response initiation, and reactivity to errors. Neurotoxicol Teratol 2001; 23:519-31. [PMID: 11792522 DOI: 10.1016/s0892-0362(01)00171-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The present study tested the hypothesis that early lead (Pb) exposure causes lasting attentional dysfunction. Long-Evans dams were fed Pb-adulterated water during gestation and/or lactation; the offspring were tested as adults. The results of a visual discrimination task revealed no Pb effects on learning rate or information-processing speed. However, lasting effects of the early Pb exposure were seen in the subsequent vigilance tasks, particularly in the final task in which onset of the visual cue and cue duration varied randomly across trials. Exposure during both gestation and lactation impaired response initiation. In addition, animals exposed to Pb during lactation only or lactation+gestation committed significantly more omission errors than controls under two specific conditions: (1) trials in which a delay was imposed prior to cue presentation and (2) trials that followed an incorrect response. The pattern of treatment differences indicated that early Pb exposure produced lasting impairment of sustained attention and increased reactivity to errors. Both effects may contribute to the cognitive impairment, problematic classroom behaviors, and increased delinquency associated with early Pb exposure in children. These findings also demonstrate that the developmental timing of the exposure determines the pattern of effects. Thus, conclusions regarding whether or not a particular cognitive or affective function is impaired or spared by early Pb exposure must be limited to the specific timing and intensity of exposure.
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Affiliation(s)
- R E Morgan
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
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