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Pistollato F, Carpi D, Mendoza-de Gyves E, Paini A, Bopp SK, Worth A, Bal-Price A. Combining in vitro assays and mathematical modelling to study developmental neurotoxicity induced by chemical mixtures. Reprod Toxicol 2021; 105:101-119. [PMID: 34455033 PMCID: PMC8522961 DOI: 10.1016/j.reprotox.2021.08.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 07/30/2021] [Accepted: 08/24/2021] [Indexed: 12/12/2022]
Abstract
Prenatal and postnatal co-exposure to multiple chemicals at the same time may have deleterious effects on the developing nervous system. We previously showed that chemicals acting through similar mode of action (MoA) and grouped based on perturbation of brain derived neurotrophic factor (BDNF), induced greater neurotoxic effects on human induced pluripotent stem cell (hiPSC)-derived neurons and astrocytes compared to chemicals with dissimilar MoA. Here we assessed the effects of repeated dose (14 days) treatments with mixtures containing the six chemicals tested in our previous study (Bisphenol A, Chlorpyrifos, Lead(II) chloride, Methylmercury chloride, PCB138 and Valproic acid) along with 2,2'4,4'-tetrabromodiphenyl ether (BDE47), Ethanol, Vinclozolin and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)), on hiPSC-derived neural stem cells undergoing differentiation toward mixed neurons/astrocytes up to 21 days. Similar MoA chemicals in mixtures caused an increase of BDNF levels and neurite outgrowth, and a decrease of synapse formation, which led to inhibition of electrical activity. Perturbations of these endpoints are described as common key events in adverse outcome pathways (AOPs) specific for DNT. When compared with mixtures tested in our previous study, adding similarly acting chemicals (BDE47 and EtOH) to the mixture resulted in a stronger downregulation of synapses. A synergistic effect on some synaptogenesis-related features (PSD95 in particular) was hypothesized upon treatment with tested mixtures, as indicated by mathematical modelling. Our findings confirm that the use of human iPSC-derived mixed neuronal/glial models applied to a battery of in vitro assays anchored to key events in DNT AOP networks, combined with mathematical modelling, is a suitable testing strategy to assess in vitro DNT induced by chemical mixtures.
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Affiliation(s)
| | - Donatella Carpi
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | | | - Alicia Paini
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | | | - Andrew Worth
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Anna Bal-Price
- European Commission, Joint Research Centre (JRC), Ispra, Italy.
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Ochiai M, Nguyen HT, Kurihara N, Hirano M, Tajima Y, Yamada TK, Iwata H. Directly Reprogrammed Neurons as a Tool to Assess Neurotoxicity of the Contaminant 4-Hydroxy-2',3,5,5'-tetrachlorobiphenyl (4'OH-CB72) in Melon-Headed Whales. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:8159-8168. [PMID: 34061511 DOI: 10.1021/acs.est.1c01074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Whales accumulate high levels of environmental pollutants. Exposure to polychlorinated biphenyls (PCBs) and their metabolites (OH-PCBs) could be linked to abnormal behavior, which may lead to mass stranding of marine mammals. Whales may thus suffer from adverse effects such as neuronal dysfunction, yet testing the neurotoxicity of these compounds has never been feasible for these species. This study established neurons chemically reprogrammed from fibroblasts of mass stranded melon-headed whales (Peponocephala electra) and used them for in vitro neurotoxicity assays. Exposure to 4-hydroxy-2',3,5,5'-tetrachlorobiphenyl (4'OH-CB72), a metabolite of PCBs, caused apoptosis in the reprogrammed neurons. Transcriptome analysis of 4'OH-CB72-treated whale neurons showed altered expressions of genes associated with oxidative phosphorylation, chromatin degradation, axonal transport, and neurodegenerative diseases. These results suggest that 4'OH-CB72 exposure may induce neurodegeneration through disrupted apoptotic processes. A comparison of the results with human reprogrammed neurons revealed the specific effects on the whale neurons. Our noninvasive approach using fibroblast-derived neurons is useful for hazard and risk assessments of neurotoxicity in whales.
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Affiliation(s)
- Mari Ochiai
- Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-cho, Matsuyama City, Ehime 790-8577, Japan
| | - Hoa Thanh Nguyen
- Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-cho, Matsuyama City, Ehime 790-8577, Japan
| | - Nozomi Kurihara
- Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1, Yoshida, Yamaguchi City, Yamaguchi 753-8515, Japan
| | - Masashi Hirano
- Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-cho, Matsuyama City, Ehime 790-8577, Japan
| | - Yuko Tajima
- Division of Vertebrates, Department of Zoology, National Museum of Nature and Science, 4-1-1, Amakubo, Tsukuba, Ibaraki 305-0005, Japan
| | - Tadasu K Yamada
- Division of Vertebrates, Department of Zoology, National Museum of Nature and Science, 4-1-1, Amakubo, Tsukuba, Ibaraki 305-0005, Japan
| | - Hisato Iwata
- Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-cho, Matsuyama City, Ehime 790-8577, Japan
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Ellsworth L, McCaffery H, Chernyak S, Lam S, Sargis RM, Padmanabhan V, Gregg B. Lactational exposure to polychlorinated biphenyls is higher in overweight /obese women and associated with altered infant growth trajectory: A pilot study. Curr Res Toxicol 2020; 1:133-140. [PMID: 34345842 PMCID: PMC8320629 DOI: 10.1016/j.crtox.2020.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 09/04/2020] [Accepted: 10/14/2020] [Indexed: 11/21/2022] Open
Abstract
Human milk levels of PCBs are higher in mothers with overweight and obesity. Lactational exposure to PCBs is associated with alterations in development. Lactational expsures to PCBs in human milk are associated with slower infant growth patterns.
Background Infant exposure to environmental chemicals, such as polychlorinated biphenyls (PCBs), may contribute to developmental programming of long-term metabolic disease risk. PCBs persist given their lipophilicity and long half-lives, allowing them to bio-accumulate in adipose tissue. These compounds can then be excreted into maternal milk resulting in infant exposure. Objective To determine the level of PCBs in milk from mothers with pre-pregnancy overweight and obese (OW/OB) versus normal weight status (NW) and evaluate the association of milk PCB levels with infant growth over the first 6 months of life. Methods A pilot study of a subset of milk samples from mothers with NW (pre-pregnancy body mass index (BMI) < 25 kg/m2, n = 11) and OW/OB (pre-pregnancy BMI ≥ 25 kg/m2, n = 8) were examined approximately 2-weeks postpartum. PCB congeners 138 + 163, 132 + 153, 180, and the sum were measured using gas chromatography/mass spectrometry and adjusted for milk fat content. Infant growth was monitored from birth to 6 months for weight-for-age (WFA), length-for-age (LFA), weight-for-length (WFL), head circumference-for-age (HCA), and associations with milk PCB content determined using linear mixed modeling. Results Total milk fat content did not differ by maternal weight status (p = 0.88). Milk from mothers with OW/OB had significantly higher PCB sum (p = 0.02) and PCB 138 + 163 (p = 0.03). PCB 132 + 153 (β −0.0008, p = 0.0218), PCB 180 (β −0.0010, p = 0.0279), and PCB sum (β −0.0006, p = 0.0138) were negatively associated with HCA Z-score growth to 6 months. PCB 180 was negatively associated with infant WFA (β −0.0015, p = 0.0058) and WFL Z-score (β −0.0016, p = 0.0263) to 6 months. There were no associations of PCB sum content with WFL, LFA, WFL Z-score over the first 6 months of life. Conclusions Maternal overweight and obesity are associated with higher levels of total PCB congeners (132, 138, 153, 163, 180) in human milk. PCB congeners have negative associations with infant head circumference and weight trajectory over the first 6 months of life.
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Key Words
- BMI, Body mass index
- EDCs, Endocrine disrupting chemicals
- GC/MS, Gas chromatography/mass spectrometry
- HCA, Head circumference-for-age
- HMA, Human Milk Analyzer
- Human milk
- IMAGE, Infant Metabolism and Gestational Endocrinopathies
- Infant growth
- LFA, Length-for-age
- LOD, Limit of detection
- PCBs, Polychlorinated biphenyls
- Polychlorinated biphenyls
- WFA, Weight-for-age
- WFL, Weight-for-length
- WHO, World Health Organization
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Affiliation(s)
- Lindsay Ellsworth
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics and Communicable Diseases, 1540 E. Medical Center Drive, University of Michigan, Ann Arbor, MI, United States
- Corresponding author at: Division of Neonatal-Perinatal Medicine, 1540 E Medical Center Drive, 8-621 Mott/4254, Ann Arbor, MI 48109-4254, United States.
| | - Harlan McCaffery
- Center for Human Growth and Development, University of Michigan, 300 N Ingalls St, Ann Arbor, MI, United States
| | - Sergei Chernyak
- Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI, United States
| | - Stephanie Lam
- Division of Pediatric Endocrinology, Diabetes, and Metabolism, Department of Pediatrics and Communicable Diseases, University of Michigan, 1540 E. Medical Center Drive, University of Michigan, Ann Arbor, MI, United States
| | - Robert M. Sargis
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, 835 S. Wolcott, Chicago, IL, United States
| | - Vasantha Padmanabhan
- Division of Pediatric Endocrinology, Diabetes, and Metabolism, Department of Pediatrics and Communicable Diseases, University of Michigan, 1540 E. Medical Center Drive, University of Michigan, Ann Arbor, MI, United States
- Department of Pediatrics and Communicable Diseases, University of Michigan, 1540 E. Medical Center Drive, University of Michigan, Ann Arbor, MI, United States
| | - Brigid Gregg
- Division of Pediatric Endocrinology, Diabetes, and Metabolism, Department of Pediatrics and Communicable Diseases, University of Michigan, 1540 E. Medical Center Drive, University of Michigan, Ann Arbor, MI, United States
- Division of Pediatric Endocrinology, Diabetes, and Metabolism, Department of Pediatrics and Communicable Diseases, University of Michigan, 1540 E. Medical Center Drive, University of Michigan, Ann Arbor, MI, United States
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Karimi B, Nabizadeh R, Yunesian M. Association Between Leukocyte Telomere Length and Serum Concentrations of PCBs and Organochlorine Pesticides. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2020; 79:122-130. [PMID: 32300848 DOI: 10.1007/s00244-020-00732-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 03/23/2020] [Indexed: 06/11/2023]
Abstract
Exposure to polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) through food, water, and air occurred during the life, which may change telomere length (TL) in peripheral blood leukocytes. The present study was designed to investigate the association between TL and serum levels of PCBs and OCPs in Tehran male's population. Whole blood samples were randomly taken from 300 adult males, aged between 25 and 40 years. TL was determined by real-time PCR to measure the number of the telomere (T) repeats to the number of a single-copy gene (S). We applied the multivariate linear regression model to compare the effect of each lipid adjusted serum levels of PCBs and OCPs congener on the TL, with adjustment for age, body mass index, education, smoking, and food patterns. Each doubling of the nondioxin-like PCBs, dioxin-like PCBs, and OCPs levels were associated with 1.9% [95% confidence interval (CI) - 0.70 to 5.40%], 2.5% (95% CI 0.30-8.3%), and - 2.4% (95% CI - 0.70 to - 6.2%) variation in the TL, respectively. The percent difference in the TL with exposure to nondioxin-like PCBs, dioxin-like PCBs, and OCPs for participants with older than age 37 years were 6.45% (95% CI 2.81-16.50%), 4.52% (95% CI 1.60-10.54%), and - 7.44% (95% CI - 1.55 to - 15.51%), respectively. Exposures to nondioxin-like PCBs (except for PCB 28 and 52) with high chlorine in structure and dioxin-like PCBs were related to longer TLs. Conversely, serum levels of OCPs can be associated with oxidative stress and systemic inflammation that lead to telomere shortening.
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Affiliation(s)
- Behrooz Karimi
- Department of Environmental Health Engineering, School of Health, Arak University of Medical Sciences, Arāk, Iran.
| | - Ramin Nabizadeh
- Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Enghelab St., Tehran, Iran
| | - Masud Yunesian
- Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Enghelab St., Tehran, Iran
- Department of Research Methodology and Data Analysis, Institute for Environmental Research (IER), Tehran University of Medical Sciences, Kargar St., Enghelab Sq., Tehran, Iran
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Naqvi A, Qadir A, Mahmood A, Baqar M, Aslam I, Jamil N, Mumtaz M, Saeed S, Zhang G. Screening of human health risk to infants associated with the polychlorinated biphenyl (PCB) levels in human milk from Punjab Province, Pakistan. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:6837-6850. [PMID: 31879876 DOI: 10.1007/s11356-019-07126-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 11/19/2019] [Indexed: 06/10/2023]
Abstract
This study assessed the polychlorinated biphenyl (PCB) levels in human milk and its associated health risk to infants from rural and urban settings of five districts of Punjab Province, Pakistan. The ∑34PCB concentrations ranged from 30.9 to 68.3 ng g-1 on lipid weight (l.w.) basis. The ∑8DL-PCB concentrations were ranged from 0.29 to 1.35 ng g-1 l.w., (mean 6.2 ± 8.7 ng g-1 l.w.), with toxicity equivalent to polychlorinated dibenzodioxins (PCDDs) ranging from 8.58 × 10-6 to 0.05 ng TEQ g-1 l.w. The spatial trend of PCB levels in human milk revealed higher bioaccumulative levels for urban mothers as compared with rural counterparts. The estimated daily intake (EDI) values of DL-PCBs to infants through trans-mammary transfer were considerably higher than tolerable daily intake limits established by WHO (i.e., 1-4 pg TEQ kg-1 bw) and other globally recognized organizations. Similarly, the hazard quotient values for TEQ ∑8DL-PCBs (range 1.21 to 79.87) were far above the benchmark value of 1 at all the sampling sites, indicating the high levels of adverse health risks to infants in the region through breast milk consumption. The ∑34PCB levels were found to be negatively correlated with mother' age (r = -0.31; p = 0.02), parity (r = - 0.85; p = 0.001), and infant' birth weight (r = - 0.73; p = 0.01). The present study suggests undertaking comprehensive public health risk assessment studies and firm regulatory measures to safeguard human health risks.
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Affiliation(s)
- Anber Naqvi
- College of Earth and Environmental Sciences, University of the Punjab, Lahore, 54590, Pakistan
| | - Abdul Qadir
- College of Earth and Environmental Sciences, University of the Punjab, Lahore, 54590, Pakistan.
| | - Adeel Mahmood
- Department of Environmental Science, Government College for Women University, Sialkot, 51310, Pakistan
| | - Mujtaba Baqar
- Sustainable Development Study Centre, Government College University, Lahore, 54000, Pakistan.
| | - Iqra Aslam
- College of Earth and Environmental Sciences, University of the Punjab, Lahore, 54590, Pakistan
| | - Nadia Jamil
- College of Earth and Environmental Sciences, University of the Punjab, Lahore, 54590, Pakistan
| | - Mehvish Mumtaz
- State Key Joint Laboratory of Environment Simulation and Pollution Control (SKJLESPC), Beijing Key Laboratory for Emerging Organic Contaminants Control (BKLEOC), School of Environment, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Salman Saeed
- Food and Biotechnology Research Center, Pakistan Council of Scientific and Industrial Research, Lahore, 54600, Pakistan
| | - Gan Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China
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Gagnon-Chauvin A, Bastien K, Saint-Amour D. Environmental toxic agents: The impact of heavy metals and organochlorides on brain development. HANDBOOK OF CLINICAL NEUROLOGY 2020; 173:423-442. [PMID: 32958188 DOI: 10.1016/b978-0-444-64150-2.00030-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Exposure to environmental toxicants can have deleterious effects on the development of physical, cognitive, and mental health. Extensive laboratory and clinical studies have demonstrated how the developing brain is uniquely sensitive to toxic agents. This chapter focuses on the main neurologic impairments linked to prenatal and postnatal exposure to lead, methylmercury, and polychlorinated biphenyls, three legacy environmental contaminants whose neurotoxic effects have been extensively studied with respect to cognitive and behavioral development. The main cognitive, emotion regulation, sensory, and motor impairments in association with these contaminants are briefly reviewed, including the underlying neural mechanisms such as neuropathologic damages, brain neurotransmission, and endocrine system alterations. The use of neuroimaging as a novel tool to better understand how the brain is affected by exposure to environmental contaminants is also discussed.
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Affiliation(s)
- Avril Gagnon-Chauvin
- Department of Psychology, Université du Québec à Montréal, Montréal, QC, Canada; Research Centre, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada
| | - Kevin Bastien
- Department of Psychology, Université du Québec à Montréal, Montréal, QC, Canada; Research Centre, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada
| | - Dave Saint-Amour
- Department of Psychology, Université du Québec à Montréal, Montréal, QC, Canada; Research Centre, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, QC, Canada.
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Berghuis SA, Roze E. Prenatal exposure to PCBs and neurological and sexual/pubertal development from birth to adolescence. Curr Probl Pediatr Adolesc Health Care 2019; 49:133-159. [PMID: 31147261 DOI: 10.1016/j.cppeds.2019.04.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Several chemical compounds are resistant to degradation and end up in the food chain. One group of these chemicals is polychlorinated biphenyls (PCBs) which are used as flame retardants and plasticizers. Although PCBs were banned several decades ago, PCBs are still found in environmental media, including in the body of humans. PCBs are transferred from mother to fetus via the placenta during pregnancy. Considering that the prenatal period is a sensitive period during which essential developmental processes take place, exposure to environmental chemicals might have considerable and permanent consequences for outcomes in later life. The aim of this review is to provide an update on the latest insights on the effects of prenatal exposure to PCBs on neurological, sexual and pubertal development in children. We give an overview of recent literature, and discuss it in the light of the findings in a unique Dutch birth cohort, with data on both neurological and pubertal development into adolescence. The findings in the studies included in this review, together with the findings in the Dutch cohort, demonstrate that prenatal exposure to PCBs can interfere with normal child development, not only during the perinatal period, but up to and including adolescence. Higher prenatal exposure to PCBs was found to be both negatively and positively associated with neurodevelopmental outcomes. Regarding pubertal development, higher prenatal PCB exposure was found to be associated with more advanced pubertal development, also in the Dutch cohort, whereas other studies also found delayed pubertal development. These findings raise concern regarding the effects of man-made chemical compounds on child development. They further contribute to the awareness of how environmental chemical compounds can interfere with child development and negatively influence healthy ageing.
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Affiliation(s)
- Sietske Annette Berghuis
- Division of Neonatology, Department of Pediatrics, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Hanzeplein 1, PO Box 30.001, 9713 GZ, Groningen, the Netherlands.
| | - Elise Roze
- Division of Neonatology, Department of Pediatrics, Wilhelmina Children's Hospital, University of Utrecht, University Medical Center Utrecht, Utrecht, the Netherlands
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Fernández-Cruz T, Martínez-Carballo E, Simal-Gándara J. Perspective on pre- and post-natal agro-food exposure to persistent organic pollutants and their effects on quality of life. ENVIRONMENT INTERNATIONAL 2017; 100:79-101. [PMID: 28089279 DOI: 10.1016/j.envint.2017.01.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 12/26/2016] [Accepted: 01/02/2017] [Indexed: 06/06/2023]
Abstract
BACKGROUND Adipose tissue constitutes a continual source of internal exposure to organic pollutants (OPs). When fats mobilize during pregnancy and breastfeeding, OPs could affect foetal and neonatal development, respectively. SCOPE AND APPROACH The main aim of this review is to deal with pre- and post-natal external exposure to organic pollutants and their effects on health, proposing prevention measures to reduce their risk. The goal is the development of a biomonitoring framework program to estimate their impact on human health, and prevent exposure by recommending some changes in personal lifestyle habits. KEY FINDINGS AND CONCLUSIONS It has been shown that new studies should be developed taking into account their cumulative effect and the factors affecting their body burden. In conclusion, several programs should continuously be developed by different health agencies to have a better understanding of the effect of these substances and to develop a unified public policy.
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Affiliation(s)
- Tania Fernández-Cruz
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Food Science and Technology Faculty, University of Vigo - Ourense Campus, E-32004 Ourense, Spain.
| | - Elena Martínez-Carballo
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Food Science and Technology Faculty, University of Vigo - Ourense Campus, E-32004 Ourense, Spain.
| | - Jesús Simal-Gándara
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Food Science and Technology Faculty, University of Vigo - Ourense Campus, E-32004 Ourense, Spain.
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Park SH, Ha E, Hong YS, Park H. Serum Levels of Persistent Organic Pollutants and Insulin Secretion among Children Age 7-9 Years: A Prospective Cohort Study. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:1924-1930. [PMID: 27266903 PMCID: PMC5132629 DOI: 10.1289/ehp147] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Revised: 03/10/2016] [Accepted: 05/20/2016] [Indexed: 05/28/2023]
Abstract
BACKGROUND Persistent organic pollutants (POPs) are endocrine disruptors and have been suggested as possible risk factors for diabetes. Few studies have been performed to investigate this association among children. OBJECTIVES In this study, we prospectively examined the relationship between the serum concentration of POPs and glucose metabolism in children. METHODS Data were collected from the Ewha Birth & Growth Cohort Study, an ongoing birth cohort study initially constructed between 2001 and 2006. In 2010-2012, the POP concentration was measured in serum from a total of 214 children, 7-9 years of age. Using fasting glucose and insulin measurements at both baseline and the second year of follow-up, the homeostatic model assessment of beta-cell function (HOMA-β) and homeostatic model assessment of insulin resistance (HOMA-IR) were calculated. Multiple linear regression analysis and a linear mixed-effects model were used to determine the relationship between POP tertiles and metabolic biomarkers. RESULTS Compared with the lowest tertile of total marker PCBs, participants in the third tertile had decreased HOMA-β values, after adjustment for age, sex, body mass index z-score, mother's education, ponderal index, and history of breastfeeding (-18.94%; 95% CI: -32.97%, -1.98%). In a linear mixed model, the HOMA-β values were still lower in subjects in the highest compared with the lowest tertile of total PCBs at the 2-year follow-up period (108.3 vs. 135.0, respectively). CONCLUSION The results of the study suggested that exposure to POPs among children might affect insulin secretory function, which could lead to an increased risk of developing diabetes. Citation: Park SH, Ha EH, Hong YS, Park H. 2016. Serum levels of persistent organic pollutants and insulin secretion among children age 7-9 years: a prospective cohort study. Environ Health Perspect 124:1924-1930; http://dx.doi.org/10.1289/EHP147.
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Affiliation(s)
| | - Eunhee Ha
- Department of Preventive Medicine,
- Department of Occupational and Environmental Medicine, and
| | - Young Sun Hong
- Department of Internal Medicine, School of Medicine, Ewha Womans University, Seoul, Korea
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Distelhorst L, Bieda A, DiMarco M, Tullai-McGuinness S. Assessing Pediatric Nurses' Knowledge About Chemical Flame Retardants. J Pediatr Nurs 2016; 31:e333-e341. [PMID: 27425788 DOI: 10.1016/j.pedn.2016.06.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 06/23/2016] [Accepted: 06/24/2016] [Indexed: 11/28/2022]
Abstract
UNLABELLED Chemical flame retardants are routinely applied to children's products and are harmful to their health. Pediatric nurses are in a key position to provide education to caregivers on methods to decrease their children's exposure to these harmful chemicals. However, a critical barrier is the absence of any program to educate nurses about chemical flame retardants. In order to overcome this barrier, we must first assess their knowledge. This article provides key highlights every pediatric nurse should know about chemical flame retardants and reports the results of a knowledge assessment study. PURPOSE The purpose of this study was to (1) assess pediatric nurses' knowledge of chemical flame retardants, (2) determine what topic areas of chemical flame retardants pediatric nurses lack knowledge in, and (3) determine the best method to educate nurses about chemical flame retardants. DESIGN AND METHODS A single sample cross-sectional questionnaire design was used. A total sample of 417 advanced practice registered nurses and registered nurses completed an online survey about chemical flame retardants. RESULTS Pediatric nurses' knowledge of chemical flame retardants was low (M=13.4 out of 51). Articles, webinars, and e-mails were the primary preferred methods for education on the subject identified as a result of the survey. CONCLUSIONS Pediatric nurses have a large knowledge deficit related to chemical flame retardants. The data collected from this study will help structure future educational formats for pediatric nurses on chemical flame retardants to increase their knowledge.
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Affiliation(s)
- Laura Distelhorst
- Frances Payne Bolton School of Nursing, Case Western Reserve University, Cleveland, OH.
| | - Amy Bieda
- Frances Payne Bolton School of Nursing, Case Western Reserve University, Cleveland, OH
| | - Marguerite DiMarco
- Frances Payne Bolton School of Nursing, Case Western Reserve University, Cleveland, OH
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Driscoll CA, Barr CS. Studying longitudinal trajectories in animal models of psychiatric illness and their translation to the human condition. Neurosci Res 2015; 102:67-77. [PMID: 26276350 DOI: 10.1016/j.neures.2015.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 08/03/2015] [Accepted: 08/04/2015] [Indexed: 10/23/2022]
Abstract
Many forms of psychopathology and/or psychiatric illness can occur through the pathways of altered environmental sensitivity, impulsivity, social functioning, and anxious responding. While these traits are also heritable, environmental conditions are known to play a critical role. The genetic factors that contribute to these traits may be adaptive in certain contexts, but can - under the environmental conditions commonly faced among modern humans - also be key moderators of risk for psychopathological outcomes. This article will discuss how animal studies inform us of the various environmental mechanisms through which prenatal or early postnatal environmental challenge can produce long-term effects on behavior and will briefly address how pre-copulatory, pre-natal and early postnatal epigenetic effects can contribute to persistent alterations in offspring behavior. Its main focus will be how nonhuman primate studies have helped us to understand how genetic vulnerability factors can moderate responses to early environmental factors, suggesting pathways through which early stress might produce long-term effects, thus pointing to systems that might moderate risk for psychiatric illnesses in humans.
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Affiliation(s)
- Carlos A Driscoll
- Section of Comparative Behavioral Genomics, NIH/NIAAA/LNG, 5625 Fishers Lane, 3S-32, Bethesda, MD 20852, USA
| | - Christina S Barr
- Section of Comparative Behavioral Genomics, NIH/NIAAA/LNG, 5625 Fishers Lane, 3S-32, Bethesda, MD 20852, USA.
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Su PH, Chen HY, Chen SJ, Chen JY, Liou SH, Wang SL. Thyroid and growth hormone concentrations in 8-year-old children exposed in utero to dioxins and polychlorinated biphenyls. J Toxicol Sci 2015; 40:309-19. [DOI: 10.2131/jts.40.309] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Pen-Hua Su
- School of Medicine, Chung Shan Medical University, Taiwan
- Department of Pediatrics, Chung Shan Medical University Hospital, Taiwan
| | - Hsiao-Yen Chen
- Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Taiwan
| | - Suh-Jen Chen
- Department of Pediatrics, Chung Shan Medical University Hospital, Taiwan
| | - Jia-Yuh Chen
- School of Medicine, Chung Shan Medical University, Taiwan
- Department of Pediatrics, Chung Shan Medical University Hospital, Taiwan
| | - Saou-Hsing Liou
- The Department of Public Health, China Medical University, Taiwan
- Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Taiwan
| | - Shu-Li Wang
- The Department of Public Health, China Medical University, Taiwan
- Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Taiwan
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Berghuis SA, Soechitram SD, Sauer PJ, Bos AF. Prenatal Exposure to Polychlorinated Biphenyls and Their Hydroxylated Metabolites is Associated with Neurological Functioning in 3-Month-Old Infants. Toxicol Sci 2014; 142:455-62. [DOI: 10.1093/toxsci/kfu196] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Cruz G, Foster W, Paredes A, Yi KD, Uzumcu M. Long-term effects of early-life exposure to environmental oestrogens on ovarian function: role of epigenetics. J Neuroendocrinol 2014; 26:613-24. [PMID: 25040227 PMCID: PMC4297924 DOI: 10.1111/jne.12181] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 06/22/2014] [Accepted: 07/15/2014] [Indexed: 12/14/2022]
Abstract
Oestrogens play an important role in development and function of the brain and reproductive tract. Accordingly, it is considered that developmental exposure to environmental oestrogens can disrupt neural and reproductive tract development, potentially resulting in long-term alterations in neurobehaviour and reproductive function. Many chemicals have been shown to have oestrogenic activity, whereas others affect oestrogen production and turnover, resulting in the disruption of oestrogen signalling pathways. However, these mechanisms and the concentrations required to induce these effects cannot account for the myriad adverse effects of environmental toxicants on oestrogen-sensitive target tissues. Hence, alternative mechanisms are assumed to underlie the adverse effects documented in experimental animal models and thus could be important to human health. In this review, the epigenetic regulation of gene expression is explored as a potential target of environmental toxicants including oestrogenic chemicals. We suggest that toxicant-induced changes in epigenetic signatures are important mechanisms underlying the disruption of ovarian follicular development. In addition, we discuss how exposure to environmental oestrogens during early life can alter gene expression through effects on epigenetic control potentially leading to permanent changes in ovarian physiology.
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Affiliation(s)
- Gonzalo Cruz
- Centro de Neurobiología y Plasticidad Cerebral, Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
- Correspondence to: Gonzalo Cruz, Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile. 2360102, Tel. 56 32 2508015,
| | - Warren Foster
- Department of Obstetrics & Gynecology, McMaster University, Hamilton, Ontario, Canada
| | - Alfonso Paredes
- Laboratorio de Neurobioquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Chile
| | - Kun Don Yi
- Syngenta Crop Protection, LLC. Greensboro, NC
| | - Mehmet Uzumcu
- Department of Animal Sciences, School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
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Díaz-Gómez N, Ares S, Hernández-Aguilar M, Ortega-García J, Paricio-Talayero J, Landa-Rivera L. Contaminantes químicos y lactancia materna: tomando posiciones. An Pediatr (Barc) 2013; 79:391.e1-5. [DOI: 10.1016/j.anpedi.2013.04.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 04/09/2013] [Indexed: 11/16/2022] Open
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16
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Vigh É, Colombo A, Benfenati E, Håkansson H, Berglund M, Bódis J, Garai J. Individual breast milk consumption and exposure to PCBs and PCDD/Fs in Hungarian infants: a time-course analysis of the first three months of lactation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2013; 449:336-344. [PMID: 23435065 DOI: 10.1016/j.scitotenv.2013.01.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 01/06/2013] [Accepted: 01/07/2013] [Indexed: 06/01/2023]
Abstract
Polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are persistent, bioaccumulative and toxic chemicals. These compounds are transferred to breast milk, therefore breastfed infants are at risk of being exposed to considerable amounts of PCBs and PCDD/Fs during this sensitive age. In the present study individual breast milk samples were collected at three time points (days 5, 12 and 84 postpartum) from 22 mothers who delivered their infants during 2007 in Baranya County, Hungary. Breast milk samples were analyzed for 17 PCDD/Fs, 12 dioxin-like (DL) PCBs and 7 non-dioxin-like (NDL) PCBs using high-resolution gas chromatography/high-resolution mass spectrometry. Each infant's daily breast milk consumptions have been measured biweekly over three months. The concentration of several PCB and PCDD congeners in breast milk decreased significantly during lactation, with a main decline between days 5 and 12. The total toxic equivalent (TEQ) concentrations, derived from PCDD/Fs and DL-PCBs, were 3.17±1.72, 2.70±1.57 and 2.41±1.47 pg TEQ/g fat at the three time points, respectively. The corresponding NDL-PCB concentrations were 33.5±29.2, 27.4±20.6 and 26.9±24.8 ng/g fat, respectively. The results highlight the importance of timing of breast milk sampling for consistent exposure assessment estimation. Levels of pollutants in Hungarian breast milk samples were at the lower concentration range when data from Europe are considered. This is the first study in Hungary where each infant's daily intakes of PCBs and PCDD/Fs via breast milk have been measured. The daily intakes of PCDD/Fs and DL-PCBs via breastfeeding per kg body weight were 11.79±6.42, 16.54±13.02 and 11.59±7.70 pg TEQ/kg bw on days 5, 12 and 84, respectively. The exposure was the highest on day 12 but at all three time points each infants' daily exposure to PCDD/Fs and DL-PCBs via breastfeeding exceeded the tolerable daily intake (TDI) of 2 pg TEQ/kg bw per day. These levels are still lower than corresponding levels recently measured in many European countries. Whether the milk-derived POP exposure levels of infants reported here constitute any health risk that may manifest later in life awaits further scrutiny.
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Affiliation(s)
- Éva Vigh
- Department of Pathophysiology and Gerontology, Medical School, University of Pécs, Szigeti út 12, H-7624 Pécs, Hungary.
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Leino O, Kiviranta H, Karjalainen A, Kronberg-Kippilä C, Sinkko H, Larsen EH, Virtanen S, Tuomisto J. Pollutant concentrations in placenta. Food Chem Toxicol 2013; 54:59-69. [DOI: 10.1016/j.fct.2011.10.058] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Revised: 09/26/2011] [Accepted: 10/21/2011] [Indexed: 11/28/2022]
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Slamecka J, Capcarova M, Jurcik R, Kolesarova A, Ondruska L, Gasparik J, Lukac N, Mertin D. The occurrence and dynamics of polychlorinated hydrocarbons in brown hare (Lepus europaeus) in south-western Slovakia. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2012; 47:1217-1223. [PMID: 22540643 DOI: 10.1080/10934529.2012.672068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This study aimed at obtaining the data on the occurrence, levels and correlations of organic pollutants present in game animals (n = 75, Brown hare, Lepus europaeus Pall.) in the region of south-western Slovakia. The analyses performed included dichlorodiphenyltrichloroethane (DDT), hexachlorobenzen (HCB), alpha- and beta hexachlorocyclohexane (α+β-HCH), gamma-hexachlorocyclohexane (γ-HCH), and polychlorinated biphenyls (PCB-delor, commercial mixture of PCB congeners). A gas chromatograph with an electron capture detector was used for the analysis. PCB-delor and DDT were accumulated significantly in the highest level (0.105 ± 0.059 mg/kg; 0.070 mg/kg) in depot fat in brown hares; however maximum permissible limits for the observed pollutants were not exceeded. Significantly higher concentrations of DDT, HCB, γ-HCH, and PCB-delor were found in adult animals when compared with juvenile hares. Gender and season had no effect on the accumulation of observed pollutants. Moderately positive correlation was found between PCB-delor and DDT (r = 0.59). Monitoring of environmental pollution with polychlorinated hydrocarbons is important with regard to public health, as game animals constitute an important part of food chain also for humans.
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Prenatal, early life, and childhood exposure to genotoxicants in the living environment. Arh Hig Rada Toksikol 2011; 61:455-64. [PMID: 21183437 DOI: 10.2478/10004-1254-61-2010-2065] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Health disorders and diseases related to environmental exposure in children such as cancer and immunologic disturbances (asthma, allergies) are on the rise. However, complex transplacental and prepubertal genotoxicology is given very limited consideration, even though intrauterine development and early childhood may be critical for elucidating the cancer aetiology. The foetus is transplacentally exposed to contaminants in food and environment such as various chemicals, drugs, radiochemically contaminated water and air. Target organs of xenobiotic action may differ between the mother and the foetus due to specific stage of developmental physiology and enzyme distribution. This in turn may lead to different levels of clastogenic and aneugenic metabolites of the same xenobiotic in the mother and the foetus. Adult's protective behaviour is not sufficient to isolate children from radioisotopes, pesticides, toxic metals and metalloids, environmental tobacco smoke, endocrine disrupting chemicals, and various food contaminants, which are just a part of the stressors present in a polluted environment. In order to improve legislation related to foetus and child exposure to genotoxic and possibly carcinogenic agents, oncologists, paediatricians, environmental health specialists, and genotoxicologists should work together much more closely to make a more effective use of accumulated scientific data, with the final aim to lower cancer incidence and mortality.
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20
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The combined effects of BDE47 and BaP on oxidatively generated DNA damage in L02 cells and the possible molecular mechanism. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2011; 721:192-8. [DOI: 10.1016/j.mrgentox.2011.02.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 01/02/2011] [Accepted: 02/05/2011] [Indexed: 12/31/2022]
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21
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Suzuki K, Nakai K, Sugawara T, Nakamura T, Ohba T, Shimada M, Hosokawa T, Okamura K, Sakai T, Kurokawa N, Murata K, Satoh C, Satoh H. Neurobehavioral effects of prenatal exposure to methylmercury and PCBs, and seafood intake: neonatal behavioral assessment scale results of Tohoku study of child development. ENVIRONMENTAL RESEARCH 2010; 110:699-704. [PMID: 20673887 DOI: 10.1016/j.envres.2010.07.001] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Revised: 06/22/2010] [Accepted: 07/02/2010] [Indexed: 05/17/2023]
Abstract
As factors affecting neonatal neurodevelopment, methylmercury, polychlorinated biphenyls (PCBs), and maternal seafood intake reflecting n-3 polyunsaturated fatty acids (PUFAs) are believed to have adverse or beneficial effects, but there are a few reports addressing such factors simultaneously. We carried out a birth cohort study to clarify the effects of these three factors on the Neonatal Behavioral Assessment Scale (NBAS), administered 3 days after birth. In a total of 498 mother-neonate pairs, the total mercury level (median, 1.96microg/g) in maternal hair at parturition and the summation operatorPCB level (45.5ng/g-lipid) in cord blood were analyzed, and maternal seafood intake was estimated using a semi-quantitative food frequency questionnaire. A negative relationship between the hair mercury level and the motor cluster of NBAS was observed, even after adjusting for PCBs, maternal seafood intake, and possible confounders such as maternal age, birth weight, and parity. The summation operatorPCB level was negatively correlated with the motor cluster, but this association was attenuated after adjusting for mercury and the confounders. There was seen to be a positive association between maternal seafood intake and the motor cluster when considering the effects of mercury and PCBs. In conclusion, our data suggest that prenatal exposure to methylmercury adversely affects neonatal neurobehavioral function; in contrast, maternal seafood intake appears to be beneficial. The neurobehavioral effect of prenatal exposure to PCBs remains unclear in our study. Further research is necessary to elucidate interactive effects of methylmercury, PCBs, and n-3 PUFAs, originating from fish, on child neurodevelopment.
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Affiliation(s)
- Keita Suzuki
- Environmental Health Sciences, Tohoku University, Graduate School of Medicine, 2-1 Seiryo-machi, Sendai, Miyagi 980-8576, Japan; Japan Society for the Promotion of Science, Tokyo, Japan
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22
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Latchney SE, Lioy DT, Henry EC, Gasiewicz TA, Strathmann FG, Mayer-Pröschel M, Opanashuk LA. Neural precursor cell proliferation is disrupted through activation of the aryl hydrocarbon receptor by 2,3,7,8-tetrachlorodibenzo-p-dioxin. Stem Cells Dev 2010; 20:313-26. [PMID: 20486776 DOI: 10.1089/scd.2009.0529] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Neurogenesis involves the proliferation of multipotent neuroepithelial stem cells followed by differentiation into lineage-restricted neural precursor cells (NPCs) during the embryonic period. Interestingly, these progenitor cells express robust levels of the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor that regulates expression of genes important for growth regulation, and xenobiotic metabolism. Upon binding 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a pervasive environmental contaminant and potent AhR ligand, AhR, is activated and disrupts gene expression patterns to produce cellular toxicity. Because of its widespread distribution in the brain during critical proliferative phases of neurogenesis, it is conceivable that AhR participates in NPC expansion. Therefore, this study tested the hypothesis that AhR activation by TCDD disrupts signaling events that regulate NPC proliferation. The C17.2 NPC line served as a model system to (1) assess whether NPCs are targets for TCDD-induced neurotoxicity and (2) characterize the effects of TCDD on NPC proliferation. We demonstrated that C17.2 NPCs express an intact AhR signaling pathway that becomes transcriptionally active after TCDD exposure. (3)H-thymidine and alamar blue reduction assays indicated that TCDD suppresses NPC proliferation in a concentration-dependent manner without the loss of cell viability. Cell cycle distribution analysis by flow cytometry revealed that TCDD-induced growth arrest results from an impaired G1 to S cell cycle transition. Moreover, TCDD exposure altered p27( kip1) and cyclin D1 cell cycle regulatory protein expression levels consistent with a G1 phase arrest. Initial studies in primary NPCs isolated from the ventral forebrain of embryonic mice demonstrated that TCDD reduced cell proliferation through a G1 phase arrest, corroborating our findings in the C17.2 cell line. Together, these observations suggest that the inappropriate or sustained activation of AhR by TCDD during neurogenesis can interfere with signaling pathways that regulate neuroepithelial stem cell/NPC proliferation, which could adversely impact final cell number in the brain and lead to functional impairments.
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Affiliation(s)
- Sarah E Latchney
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642, USA
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Affiliation(s)
- Ibone Olza
- Child Psychiatry Unit, Department of Psychiatry, Hospital Universitario Puerta de Hierro Majadahonda, Madrid, Spain
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Luo ZC, Liu JM, Fraser WD. Large prospective birth cohort studies on environmental contaminants and child health - goals, challenges, limitations and needs. Med Hypotheses 2010; 74:318-24. [PMID: 19765909 PMCID: PMC3035639 DOI: 10.1016/j.mehy.2009.08.044] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Accepted: 08/24/2009] [Indexed: 12/29/2022]
Abstract
The adverse health effects of environmental contaminants (ECs) are a rising public health concern, and a major threat to sustainable socioeconomic development. The developing fetuses and growing children are particularly vulnerable to the adverse effects of ECs. However, assessing the health impact of ECs presents a major challenge, given that multiple outcomes may arise from one exposure, multiple exposures may result in one outcome, and the complex interactions between ECs, and between ECs, nutrients and genetic factors, and the dynamic temporal changes in EC exposures during the life course. Large-scale prospective birth cohort studies collecting extensive data and specimen starting from the prenatal or pre-conception period, although costly, hold promise as a means to more clearly quantify the health effects of ECs, and to unravel the complex interactions between ECs, nutrients and genotypes. A number of such large-scale studies have been launched in some developed counties. We present an overview of "why", "what" and "how" behind these efforts with an objective to uncover major unidentified limitations and needs. Three major limitations were identified: (1) limited data and bio-specimens regarding early life EC exposure assessments in some birth cohort studies; (2) heavy participant burdens in some birth cohort studies may bias participant recruitment, and risk substantial loss to follow-up, protocol deviations limiting the quality of data and specimens collection, with an overall potential bias towards the null effect; (3) lack of concerted efforts in building comparable birth cohorts across countries to take advantage of natural "experiments" (large EC exposure level differences between countries) for more in-depth assessments of dose-response relationships, threshold exposure levels, and positive and negative effect modifiers. Addressing these concerns in current or future large-scale birth cohort studies may help to produce better evidence on the health effects of ECs.
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Affiliation(s)
- Zhong-Cheng Luo
- Department of Obstetrics and Gyneocology, Sainte Justine Hospital, University of Montreal, Quebec, Canada.
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Roze E, Meijer L, Bakker A, Van Braeckel KNJA, Sauer PJJ, Bos AF. Prenatal exposure to organohalogens, including brominated flame retardants, influences motor, cognitive, and behavioral performance at school age. ENVIRONMENTAL HEALTH PERSPECTIVES 2009; 117:1953-8. [PMID: 20049217 PMCID: PMC2799472 DOI: 10.1289/ehp.0901015] [Citation(s) in RCA: 290] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2009] [Accepted: 08/31/2009] [Indexed: 05/02/2023]
Abstract
BACKGROUND Organohalogen compounds (OHCs) are known to have neurotoxic effects on the developing brain. OBJECTIVE We investigated the influence of prenatal exposure to OHCs, including brominated flame retardants, on motor, cognitive, and behavioral outcome in healthy children of school age. METHODS This study was part of the prospective Groningen infant COMPARE (Comparison of Exposure-Effect Pathways to Improve the Assessment of Human Health Risks of Complex Environmental Mixtures of Organohalogens) study. It included 62 children in whose mothers the following compounds had been determined in the 35th week of pregnancy: 2,2'-bis-(4 chlorophenyl)-1,1'-dichloroethene, pentachlorophenol (PCP), polychlorinated biphenyl congener 153 (PCB-153), 4-hydroxy-2,3,3',4',5-pentachlorobiphenyl (4OH-CB-107), 4OH-CB-146, 4OH-CB-187, 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), BDE-99, BDE-100, BDE-153, BDE-154, and hexabromocyclododecane. Thyroid hormones were determined in umbilical cord blood. When the children were 5-6 years of age, we assessed their neuropsychological functioning: motor performance (coordination, fine motor skills), cognition (intelligence, visual perception, visuomotor integration, inhibitory control, verbal memory, and attention), and behavior. RESULTS Brominated flame retardants correlated with worse fine manipulative abilities, worse attention, better coordination, better visual perception, and better behavior. Chlorinated OHCs correlated with less choreiform dyskinesia. Hydroxylated polychlorinated biphenyls correlated with worse fine manipulative abilities, better attention, and better visual perception. The wood protective agent (PCP) correlated with worse coordination, less sensory integrity, worse attention, and worse visuomotor integration. CONCLUSIONS Our results demonstrate for the first time that transplacental transfer of polybrominated flame retardants is associated with the development of children at school age. Because of the widespread use of these compounds, especially in the United States, where concentrations in the environment are four times higher than in Europe, these results cause serious concern.
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Affiliation(s)
- Elise Roze
- Division of Neonatology, Beatrix Children's Hospital, University Medical Center Groningen, the Netherlands.
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Abstract
Common environmental exposures may affect thyroid function in humans. Foetuses and infants are most vulnerable to these effects because they need thyroid hormone for normal neurodevelopment. Perchlorate, thiocyanate and nitrate are all competitive inhibitors of the sodium/iodine symporter (NIS) in pharmacologic doses, but their effects on human thyroid function at environmental exposure levels remain unclear. Many compounds, including polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs), bisphenol-A (BPA) and triclosan, may have direct actions on the thyroid hormone receptor, but these effects are complex and are not yet well understood. Isoflavones inhibit thyroperoxidase (TPO) activity, and, therefore, may cause goitre and hypothyroidism if ingested at high levels, particularly in iodine-deficient individuals. Organochlorine pesticides and dioxins may decrease serum T(4) half-life by activating hepatic enzymes. Additional studies are needed to further elucidate the risk posed by these and other potentially thyroid-disrupting compounds.
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Affiliation(s)
- Elizabeth N Pearce
- Section of Endocrinology, Diabetes, and Nutrition, Boston University Medical Center, 88 East Newton street, Evans 201, Boston, MA 02118, USA.
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Yuan J, Lu WQ, Zou YL, Wei W, Zhang C, Xie H, Chen XM. Influence of aroclor 1254 on benzo(a)pyrene-induced DNA breakage, oxidative DNA damage, and cytochrome P4501A activity in human hepatoma cell line. ENVIRONMENTAL TOXICOLOGY 2009; 24:327-333. [PMID: 18767135 DOI: 10.1002/tox.20427] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Both polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) are important environmental pollutants. They coexist widely in the environment at very low levels. Numerous studies indicated that aroclor1254 (one of PCBs mixture) is the inducer of cytochrome P450 1A enzyme acitivity. Benzo(a)pyrene (BaP) can cause a variety of toxicities in vitro, such as oxidative DNA damage and genotoxicity. In the present study, HepG2 cells were treated with either BaP (50 microM) or aroclor1254 at concentrations of 11.5 (low), 23.0 (medium), and 46.0 microM (high) alone, or pretreated the cells with aroclor1254 (11.5, 23.0, and 46.0 microM), followed by BaP (50 microM). It was found that 7-ethoxyresorufin-O-deetylase (EROD) activities of HepG2 cells exposed to either BaP or aroclor 1254 increased. DNA damage measured by DNA migration and the formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) also increased in cells exposed to BaP, but not in cells exposed to aroclor1254. Under the Aroclor 1254 pretreatment condition, BaP-induced EROD activities was enhanced in cells exposed to the medium and high concentrations of aroclor1254 (P < 0.01 for both), whereas in all pretreatment groups aroclor1254 significantly increased BaP-induced DNA migration (P < 0.01 for all) and the 8-OHdG formation (P < 0.05 for all). In addition, there was positive correlation between the EROD induction activity and Olive tail moment (r(2) = 0.958, P < 0.01) or the levels of 8-OHdG (r(2) = 0.992, P < 0.01). The findings suggest that under the experimental conditions aroclor1254 may enhance BaP-induced DNA migration and oxidative DNA damage in HepG2, due to inducing CYP1A enzyme activity.
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Affiliation(s)
- Jing Yuan
- Department of Occupational and Environmental Health, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
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Endocrine disrupting polyhalogenated organic pollutants interfere with thyroid hormone signalling in the developing brain. THE CEREBELLUM 2009; 7:26-37. [PMID: 18418666 DOI: 10.1007/s12311-008-0004-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Persistent polyhalogenated organic pollutants are present worldwide and accumulate along the food chain. They interfere with human and animal health and are particularly harmful for pre- and perinatal neurodevelopment. The mechanisms behind the observed effects vary depending on the specific compound investigated. Co-planar polychlorinated biphenyls (PCBs) can act via the arylhydrocarbon receptor while many ortho-substituted PCBs disrupt intracellular Ca(2+) homeostasis. A common mechanism for a wide variety of PCBs is interference with thyroid hormone (TH) signalling in developing brain, by changing intracellular TH availability or by interacting directly at the level of the TH receptors. Studies on gene expression in cortex and cerebellum revealed both hypothyroid- and hyperthyroid-like effects. However, since THdependent gene expression plays a crucial role in the coordination of neuronal proliferation, migration, synaptogenesis, myelination, etc., both reduced/delayed and increased/premature expression may result in permanent structural changes in neuronal communication networks, leading to lifelong deficits in cognitive performance, motor functions, and psychobehavior. In a similar way, PCBs are able to interfere with estrogen- and androgen-dependent brain development and in some studies neurobehavioral outcome was shown to be gender-specific. Other persistent organohalogens like polychlorinated dibenzo-p-dioxins (PCDDs) and polybrominated diphenyl ethers (PBDEs) also act as endocrine disrupters in the developing brain. Several of the mechanisms involved are similar to those of PCBs, but each group also works via own specific pathways. The fact that persistent organohalogens can amplify the neurotoxic effects of other environmental pollutants, such as heavy metals, further increases their risk for human and animal neurodevelopment.
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Hillemeier MM, Farkas G, Morgan PL, Martin MA, Maczuga SA. Disparities in the prevalence of cognitive delay: how early do they appear? Paediatr Perinat Epidemiol 2009; 23:186-98. [PMID: 19775380 PMCID: PMC3439196 DOI: 10.1111/j.1365-3016.2008.01006.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cognitively delayed children are at risk for poor mental and physical health throughout their lives. The economically disadvantaged and some race/ethnic groups are more likely to experience cognitive delay, but the age at which delays first emerge and the underlying mechanisms responsible for disparities are not well understood. The objective of this study was to determine when sociodemographic disparities in cognitive functioning emerge, and identify predictors of low cognitive functioning in early childhood. Data were from 7308 singleton and 1463 multiple births in the Early Childhood Longitudinal Study-Birth Cohort (ECLS-B), a nationally representative cohort of children born in the USA in 2001. Multiple logistic regression analyses examined associations between sociodemographic characteristics and low cognitive functioning at 9 and 24 months, and tested whether gestational and birth-related factors mediate these associations. Sociodemographic characteristics were statistically significant predictors of low cognitive functioning among singletons at 24 months, including the three lowest quintiles of socio-economic status [lowest quintile, odds ratio (OR) = 2.7, 95% confidence interval [CI][1.7, 4.1]], non-white race/ethnicity (African American OR = 1.8 [95% CI 1.3, 2.5], Hispanic OR = 2.3 [95% CI 1.6, 3.2]), and gender (male OR = 2.1, [95% CI 1.7, 2.5]). Gestational and birth characteristics associated with low cognitive function at 9 months included very low and moderately low birthweight (OR = 55.0 [95% CI 28.3, 107.9] and OR = 3.6 [95% CI 2.6, 5.1]), respectively, and very preterm and moderately preterm delivery (OR = 3.6 [95% CI 2.0, 6.7] and OR = 2.4 [95% CI 1.7, 3.5]), respectively, but they had weaker effects by 24 months (ORs for birthweight: 3.7 [95% CI 2.3, 5.9] and 1.8 [95% CI 1.4, 2.3]; ORs for preterm: 1.8 [95% CI 1.1, 2.9] and 0.9 [95% CI 0.7, 1.3]). Results for multiple births were similar. Sociodemographic disparities in poor cognitive functioning emerged by 24 months of age, but were not mediated by gestational or birth characteristics. Further investigation of processes whereby social disadvantage adversely affects development prior to 24 months is needed.
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Affiliation(s)
- Marianne M Hillemeier
- Department of Health Policy and Administration, Pennsylvania State University, University Park, PA 16802, USA.
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Lee SK, Hamer D, Bedwell CL, Lohitnavy M, Yang RSH. Effect of PCBs on the lactational transfer of methyl mercury in mice: PBPK modeling. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2009; 27:75-83. [PMID: 20046988 PMCID: PMC2707941 DOI: 10.1016/j.etap.2008.08.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
MeHg and PCB exposure to lactating mice were analyzed and a physiologically-based pharmacokinetic (PBPK) model was developed to describe the lactational transfer of MeHg in mice. The influence of albumin on the lactational transfer of MeHg was incorporated into the PBPK model. Experimental results with lactating mice and their pups showed that co-exposure with PCB congeners increased the lactational transfer of MeHg to the pups, which was associated with the rise of albumin levels in maternal blood. Observed results were matched with PBPK model simulations conducted under the assumptions that (1) MeHg bound to plasma albumin is transferred to maternal milk, and (2) PCB congeners may increase the lactational transfer of MeHg by escalating albumin levels in maternal blood. Further refinement of PBPK model quantitatively described the pharmacokinetic changes of MeHg by co-exposure with PCBs in pup's tissues.
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Affiliation(s)
- Sun Ku Lee
- Quantitative and Computational Toxicology Group, Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collin, CO 80523
| | - Dwayne Hamer
- Veterinary Diagnostic Laboratory, Colorado State University, Fort Collins, CO 80523
| | - Cathy L. Bedwell
- Veterinary Diagnostic Laboratory, Colorado State University, Fort Collins, CO 80523
| | | | - Raymond S. H. Yang
- Quantitative and Computational Toxicology Group, Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collin, CO 80523
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Maternal fish and other seafood intakes during pregnancy and child neurodevelopment at age 4 years. Public Health Nutr 2008; 12:1702-10. [PMID: 19026093 DOI: 10.1017/s1368980008003947] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To analyse the relationship between maternal intakes of fish and other seafood during pregnancy and child neurodevelopment at age 4 years. Although pregnant women are advised to limit seafood intakes because of possible neurotoxin contamination, several studies suggest that overall maternal seafood intakes are associated with improved child neurodevelopment, perhaps because of higher DHA intakes. DESIGN The study uses data from a prospective birth cohort study. Maternal seafood intakes were assessed using a semi-quantitative FFQ administered shortly after delivery. Multivariate linear regression was used to estimate associations between seafood consumption and scores on the McCarthy Scales of Children's Abilities (MCSA). Analyses were stratified by breast-feeding duration as breast milk is a source of DHA during the postnatal phase of the brain growth spurt. SETTING Menorca, Spain, 1997-2001. SUBJECTS Full-term children (n 392) with data on maternal diet in pregnancy, breast-feeding duration and neurodevelopment at age 4 years. RESULTS Among children breast-fed for <6 months, maternal fish intakes of >2-3 times/week were associated with significantly higher scores on several MCSA subscales compared with intakes < or =1 time/week. There was no association among children breast-fed for longer periods. Maternal intakes of other seafood (shellfish/squid) were, however, inversely associated with scores on several subscales, regardless of breast-feeding duration. CONCLUSIONS The study suggests that moderately high intakes of fish, but not other seafood, during pregnancy may be beneficial for neurodevelopment among children breast-fed for <6 months. Further research in other populations with high seafood intakes and data on additional potential confounders are needed to confirm this finding.
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Bergkvist C, Oberg M, Appelgren M, Becker W, Aune M, Ankarberg EH, Berglund M, Håkansson H. Exposure to dioxin-like pollutants via different food commodities in Swedish children and young adults. Food Chem Toxicol 2008; 46:3360-7. [PMID: 18789370 DOI: 10.1016/j.fct.2008.07.029] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2007] [Revised: 06/28/2008] [Accepted: 07/08/2008] [Indexed: 11/17/2022]
Abstract
The dietary intake of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) in terms of toxic equivalents (TEQs) was investigated in Swedish children and young adults. Exposure was estimated from concentration data of six groups of individual food commodities (meat, fish, dairy products, egg, edible fats and other foodstuff) combined with food intake data from a 7-day record book obtained from 670 individuals aged 1-24 years. The results showed that Swedish boys and girls, up to the age of ten, had a median TEQ intake that exceeded the tolerable daily intake (TDI) of 2 pg TEQ/kg body weight. Children exceeding the TDI varied from almost all individuals among the youngest children to about 20% among young men and women. Dairy and fish products were the main sources of exposure for the average child, accounting for 59% of the total TEQ intake. The individuals most highly exposed were, on the other hand, characterized by a high consumption of fish. Since children constitute a vulnerable group, results obtained from the present study show that it is essential to perform age specific dietary intake assessments of pollutants and more carefully consider sensitive and/or highly exposed groups in the population in the risk management processes.
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Affiliation(s)
- Charlotte Bergkvist
- Institute of Environmental Medicine, Karolinska Institutet, P.O. Box 210, SE-171 77, Stockholm, Sweden
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Raab U, Preiss U, Albrecht M, Shahin N, Parlar H, Fromme H. Concentrations of polybrominated diphenyl ethers, organochlorine compounds and nitro musks in mother's milk from Germany (Bavaria). CHEMOSPHERE 2008; 72:87-94. [PMID: 18328530 DOI: 10.1016/j.chemosphere.2008.01.053] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2007] [Revised: 01/22/2008] [Accepted: 01/25/2008] [Indexed: 05/26/2023]
Abstract
The aim of this study was to determine a new spectrum of substances that will be selected for future breast milk monitoring in Bavaria, Germany. Up to now, the analysis of breast milk in Bavaria was limited to selected organochlorine pesticides (OCP) and polychlorinated biphenyls (PCB). Information on background levels of toxicologically interesting substances, such as dioxins and dioxin-like polychlorinated biphenyls (dl-PCB) or on flame retardants, such as polybrominated diphenyl ethers (PBDE) are very limited or not available for Bavaria. We present here levels on OCP, some nitro musks, indicator PCB, polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and dl-PCB concentrations in breast milk collected at 12 weeks post-partum of 43 primiparous mothers living in Bavaria. The average concentrations of PCDD, PCDF and dl-PCB were 4.98, 4.93 and 9.92 pg WHO-TEQ g(-1) lipid, respectively. The mean contribution of PCDD, PCDF, non-ortho and mono-ortho PCB to the total WHO-TEQ is consistently about 25% each. Furthermore the concentration on PBDE in breast milk at two sampling points, 12 weeks and 16 weeks after delivery, were determined. Overall, 19 PBDE congeners were analysed, however the level of 12 PBDE congeners were below the limit of detection. BDE-153 and BDE-47 were the predominant congeners accounting for about 66% of the total PBDE. The means of the total concentrations of PBDE (five congeners) at the first and second sampling point were 1.90 and 2.03 ng g(-1) lipid, respectively. Based on our results the overall concentrations of the analysed substances in milk samples from Bavaria are consistent with the levels of breast milk samples of other European countries reflecting the low background body burden of these compounds.
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Affiliation(s)
- Ulla Raab
- Bavarian Health and Food Safety Authority, Department of Environmental Health, Veterinaerstrasse 2, D-85764 Oberschleissheim, Germany.
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Renfrew MJ, Hay AMW, Shelton N, Law G, Wallis S, Madden S, Shires S, Sutcliffe A, Woolridge MW. Assessing levels of contaminants in breast milk: methodological issues and a framework for future research. Paediatr Perinat Epidemiol 2008; 22:72-86. [PMID: 18173786 DOI: 10.1111/j.1365-3016.2007.00893.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To assess the scale of the possible exposure by the breast-fed infant to potentially harmful substances in breast milk, methodologically robust studies are essential. Many studies in this field, however, do not report details of crucial issues such as recruitment and milk sampling. The aims of the study reported here were to develop robust methods for the study of contaminants in breast milk, and to develop a framework for future research and population monitoring. Three cohorts of women and babies were recruited by midwives from five sites in northern England. Cohort 1 (cross-sectional, n = 322) were asked to provide two milk samples, one at one week following birth and one at a subsequent time point. Cohort 2 (longitudinal, n = 54) were asked to provide five samples at specified time points over the first 12-16 weeks after birth. Cohort 3 (convenience, n = 18), mothers of babies in the Special Care Unit, were asked to donate surplus breast milk. A novel method of analysing fat concentration in small volumes was developed and tested. A randomly selected set of samples from different donors and stages of lactation was screened for organochlorine pesticide residues, polychlorinated biphenyls, dioxins/furans, phthalates and heavy metals. A total of 453 samples were donated. Cohort 3 was the least successful route of recruitment. Cohorts 1 and 2 combined were most representative of the population. Sample collection, transport and storage procedures, and the collection of data on life style and diet, were robust and acceptable to women. Midwifery involvement in recruitment was an essential component. This study offers a framework both for the conduct of future research studies, and for the establishment of regional and national monitoring mechanisms for contaminants in breast milk. Similar work on contaminants in formula as fed to babies is needed to inform risk assessment methods.
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Affiliation(s)
- Mary J Renfrew
- Mother and Infant Research Unit, Department of Health Sciences, University of York, York, UK.
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Pulina G, Nudda A, Battacone G, Cannas A. Effects of nutrition on the contents of fat, protein, somatic cells, aromatic compounds, and undesirable substances in sheep milk. Anim Feed Sci Technol 2006. [DOI: 10.1016/j.anifeedsci.2006.05.023] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Koppe JG, Bartonova A, Bolte G, Bistrup ML, Busby C, Butter M, Dorfman P, Fucic A, Gee D, van den Hazel P, Howard V, Kohlhuber M, Leijs M, Lundqvist C, Moshammer H, Naginiene R, Nicolopoulou-Stamati P, Ronchetti R, Salines G, Schoeters G, ten Tusscher G, Wallis MK, Zuurbier M. Exposure to multiple environmental agents and their effect. Acta Paediatr 2006; 95:106-13. [PMID: 17000577 DOI: 10.1080/08035320600886646] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
INTRODUCTION All children are exposed to multiple physical, chemical and biological challenges that can result in adverse health effects before and after birth. In this context, the danger of multiple exposures cannot be assessed from a single-chemical approach as used in classical toxicology. AIM To open up a 'negotiation space' for the problem of multiple exposure to environmental stressors, defined as any physical, chemical or biological entity that can induce an adverse response. In this context, two further questions obtain: to what extent can synergistic risks be assessed, and how far could potential adverse effects be prevented by enhanced regulation? METHODS A discussion of two general approaches is taken: 1) the investigation of mixtures such as smoking or air pollution without specifying the individual agents, and 2) the investigation of individual substances with a focus on possible interactions in the context of dose to receptor. RESULTS Although mixtures of compounds can have effects, it may not be possible to ascribe causation to a single compound. Furthermore, cumulative low-dose insult can, in some circumstances, be more toxic than a single high-dose exposure, e.g. endocrine disruptive effects of a combination of PCBs and dioxins which disrupt the thyroid hormone status; this tends to contradict elements of classical toxicology, . These cumulative insults may further combine with heavy metals and can disrupt the heme synthesis. It is possible that groups of pollutants could be used to test their cumulative capacity to multiple stress-susceptible receptor targets as is done in smoking and air pollution. This methodology could be used for further groups of potential pollutants, for example those associated with cleaning products, or cosmetics. Testing individual substances with a focus on interactions means that not only chemicals but also concurrent diseases should be taken into account. We suggest that the enhanced regulation of potential multiple stressors falls into two discrete categories. The first comprises a more precautionary approach (as demonstrated by the banning of chemicals such as some brominated flame retardants in Europe). The second comprises a more 'permissive' liberal approach involving the initial study of an individual compound, and subsequent interrogation of that compound in combination with another (as demonstrated by lowering the carcinogenicity of aflatoxin by vaccination against hepatitis B). CONCLUSIONS It is necessary to define and study groups of multiple stressors as in US EPA's Framework for Cumulative Risk Assessment (U.S. EPA 2003). Recent increased knowledge of the greater sensitivity of the unborn baby, the infant and the child, has led to general recognition that a higher degree of precaution is now needed in regulating for multiple stressors on the young. The more liberal permissive approach proceeding from established effects of the individual exposures is becoming less acceptable now that we know that there is much we do not understand about chronic effects of stressors during the early development phases. Conflicts over which approach to take may have to be resolved through engagement and negotiation with a wide community of stakeholders. This "community of interest" may include fundamental research scientists, practicing clinical paediatricians, patient groups, and others concerned with the health and wellbeing of infants and children.
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Affiliation(s)
- Janna G Koppe
- Ecobaby Foundation and Emma Children's Hospital Academic Medical Centre University of Amsterdam, The Netherlands.
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Leeners B, Rath W, Kuse S, Neumaier-Wagner P. Breast-feeding in women with hypertensive disorders in pregnancy. J Perinat Med 2006; 33:553-60. [PMID: 16318622 DOI: 10.1515/jpm.2005.099] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AIMS Breast feeding is particularly important and difficult in children born prematurely, especially after hypertensive diseases in pregnancies (HDP). Therefore, we aimed to investigate breast feeding in women who developed HDP. METHODS Data on breast-feeding was collected within a nationwide research project on psychosocial factors in HDP. A self-administered questionnaire was given to 2600 women with a suspected history of HDP and 1233 controls. After matching and confirming diagnosis according to ISSHP criteria, 877 women with HDP and 623 controls were included into the study. RESULTS Control women initiated (48.9/39.2%; P<0.001) and continued (42.2/37.2%; P<0.005) breast-feeding significantly more often than women with HDP. This holds particularly for women who developed HELLP syndrome (48.9/34.7%; P<0.0001, 42.2/33.5%; P<0.0001). A delivery before the 32(nd) gestational week (19.5/81.8%; P<0.0001) and a birth weight of less than 1500 g (18.8/75%; P<0.0001) were associated with the decision not to breast-feed. CONCLUSIONS Women affected by HDP breast fed significantly less often than control women. This effect is at least partly caused by the increased rate of prematurity. Encouraging and supporting these women in breast-feeding is important to improve neonatal physical and mental development.
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Affiliation(s)
- Brigitte Leeners
- Department of Gynecology and Obstetrics, University Hospital Zürich, Zürich, Switzerland.
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Foster WG, Holloway AC, Hughes CL. Dioxin-like activity and maternal thyroid hormone levels in second trimester maternal serum. Am J Obstet Gynecol 2005; 193:1900-7. [PMID: 16325590 DOI: 10.1016/j.ajog.2005.08.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2004] [Revised: 06/30/2005] [Accepted: 08/08/2005] [Indexed: 10/25/2022]
Abstract
OBJECTIVE Developmental exposure to dioxin-like compounds has been associated with cognitive and motor impairments in children. These toxicants have been shown to be thyroid toxicants in animal studies. Therefore, the objective of this study was to quantify the overall dioxin-like activity in maternal serum and determine the association between dioxin-like activity and thyroid hormone levels. STUDY DESIGN Cross-sectional examination of serum from pregnant women (n = 150) attending a prenatal diagnosis clinic between January 2002 and December 2003. RESULTS Serum dioxin-like activity was measured in 145 of 150 (96.7%) maternal serum samples. The mean (+/- SEM) serum lipid-adjusted dioxin-like activity was 0.34 +/- 0.01 pg/g. Multiple regression analysis failed to demonstrate a relationship between maternal serum dioxin-like activity and serum thyroid hormone levels. CONCLUSION Dioxin-like activity is quantifiable in an overwhelming majority of second-trimester maternal serum samples but there was no relationship between dioxin-like activity and thyroid hormone levels in our study population.
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Affiliation(s)
- Warren G Foster
- Reproductive Biology Division, Department of Obstetrics and Gynecology, McMaster University, Health Sciences Centre, Hamilton, Ontario, Canada.
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Vermeir G, Viaene M, Staessen J, Hond ED, Roels HA. Neurobehavioural investigations in adolescents exposed to environmental pollutants. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2005; 19:707-13. [PMID: 21783546 DOI: 10.1016/j.etap.2004.12.041] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Environmental exposures to industrial pollutants have been associated with lowered intelligence and behavioural problems. The Flemish Environmental and Health Study focussed on biomonitoring of exposure and associated health effects. This part of the study investigated neurobehavioural performance in adolescents in relation to lead (blood Pb), cadmium (urine Cd), polychlorinated biphenyls (PCB concentration of congeners 138, 153 and 180) and compounds with 'dioxin-like' activity (measured by the CALUX-assay). One-hundred and twenty girls and 80 boys (mean age 17.4 years) were enrolled. The NES battery was used to assess simple reaction time, switching attention, digit span forward, hand-eye coordination and symbol-digit substitution (SDS). Multiple regression analysis was performed to study dose-effect relationships between the neurobehavioural outcome variables and the exposure parameters in boys and girls. Slowing of SDS with increasing logPbB and logCdU was seen in boys only (PbB 39-1549nmol/L, CdU 0.02-0.40nmol/mmol creatinine). No dose-effect relations were found with serum PCB concentrations or CALUX-TEQs. Only one of several tests showed a performance decrease related to given environmental exposures to heavy metals. Further studies are needed to clarify whether the pattern of results reflects gender effects or the different exposure characteristics of boys and girls in our study.
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Affiliation(s)
- Griet Vermeir
- Neurotoxicology Expertise Center, Flemish Agency for Mental Health, Pas 200, 2440 Geel, Belgium
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Affiliation(s)
- Adriano Cattaneo
- Unit for Health Services Research and International Health, Child Health Institute, Trieste, Italy, E-mail:
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Feldman R, Eidelman AI. Direct and indirect effects of breast milk on the neurobehavioral and cognitive development of premature infants. Dev Psychobiol 2003; 43:109-19. [PMID: 12918090 DOI: 10.1002/dev.10126] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Eighty-six premature infants were tested to examine the effects of maternal breast milk on infant development. Infants were classified by breast-milk consumption during the hospitalization period (M = 57.4 days) into three groups: those receiving minimal (<25% of nutrition), intermediate (25-75%), and substantial (>75%) amounts of breast milk. Infants in the three groups were matched for birth weight, gestational age (GA), medical risk, and family demographics. At 37 weeks GA, mother-infant interaction was videotaped, maternal depression self-reported, and neurobehavioral maturation assessed by the Neonatal Behavior Assessment Seale (Brazelton, 1973). At 6 months corrected age, infants were tested with the Bayley II (Bayley, 1993). Infants receiving substantial amounts of breast milk showed better neurobehavioral profiles-in particular, motor maturity and range of state. These infants also were more alert during social interactions, and their mothers provided more affectionate touch. Higher maternal depression scores were associated with lower quantities of breast milk, longer latencies to the first breast-milk feeding, reduced maternal affectionate touch, and lower infant cognitive skills. Maternal affectionate touch moderated the relations between breast milk and cognitive development, with infants receiving a substantial amount of breast milk and frequent touch scoring the highest. In addition to its nutritional value, breast milk may be related to improved maternal mood and interactive behaviors, thereby indirectly contributing to development in premature infants.
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Affiliation(s)
- Ruth Feldman
- Department of Psychology, Bar-Ilan University, Ramat-Gan, Israel, 52900
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Karmaus W, Davis S, Chen Q, Kuehr J, Kruse H. Atopic manifestations, breast-feeding protection and the adverse effect of DDE. Paediatr Perinat Epidemiol 2003; 17:212-20. [PMID: 12675789 DOI: 10.1046/j.1365-3016.2003.00488.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Despite the numerous studies on the possible protective effect of breast feeding against the onset of atopic manifestations during childhood, this issue remains controversial. As part of an environmental epidemiological study, we investigated whether different blood concentrations of dichlorodiphenyl-dichloroethylene (DDE) modified the protective effect of breast feeding against atopic manifestations in 338 children. DDE concentration, duration of breast feeding and manifestation of atopic disorders were measured in 1994-95 at age 7-8 years. Information gathered on asthma, atopic eczema and hay fever was based on questionnaire data. We measured the total serum concentration of immunoglobulin E (IgE) and specific IgE levels against inhalant allergens. In 1997, we also determined bronchial hyper-reactivity with a hypertonic saline challenge test. To estimate odds ratios from our cross-sectional analysis, we applied logistic regressions, controlling for confounders. Breast feeding had a protective effect on the two asthma variables (e.g.> 12 weeks breast feeding for doctor-diagnosed asthma, OR = 0.32 [95% CI 0.11, 0.87]; for 'ever' asthma, OR = 0.13 [95% CI 0.02, 0.68]), but not on bronchial hyper-reactivity, hay fever, atopic eczema or the two IgE variables. The protective effect became stronger in children with DDE blood levels below the median of 0.29 micro g/L (e.g. doctor-diagnosed asthma,> 12 weeks breast feeding, OR = 0.24 [95% CI 0.06, 0.95]). Also, for specific IgE against inhalant allergens, the association gained statistical significance. For children with a DDE concentration of 0.29 micro g/L and higher, breast feeding did not show a significant protective effect. Our results suggest that contaminants such as DDE may modify the protective effect and may have contributed to inconsistent findings on the protective effect of breast feeding in previous studies. We recommend determining levels of breast milk contaminants in children when assessing the impact of breast feeding on atopic manifestations.
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Affiliation(s)
- Wilfried Karmaus
- Department of Epidemiology, Michigan State University, East Lansing, MI 48823, USA.
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Cheng SB, Kuchiiwa S, Kawachi A, Gao HZ, Gohshi A, Kozako T, Kuchiiwa T, Nakagawa S. Up-regulation of methionine-enkephalin-like immunoreactivity by 2,3,7,8-tetrachlorodibenzo-p-dioxin treatment in the forebrain of the Long-Evans rat. J Chem Neuroanat 2003; 25:73-82. [PMID: 12663056 DOI: 10.1016/s0891-0618(02)00103-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is considered to be one of the most toxic environmental contaminants, named dioxin. Exposure to TCDD induces a plethora of intoxication symptoms, including anorexia and hypothermia, in several mammals and human. Enkephalin, an endogenous pentapeptide, is an important neuroregulator of autonomic functions, such as food intake and body temperature. In this study, we investigated the effects of TCDD gastric administration on methionine-enkephalin (MEK) immunoreactivity in the brain of the Long-Evans rat, the species strain considered to be the most TCDD-susceptible, using immunohistochemical staining. A single dose of TCDD (dissolved in olive oil, 50 microg/kg) or olive oil alone was administrated to the rats by gavage. Compared with the vehicle-treated rat, a marked increase in the density of MEK immunoreactive cell bodies, fibers and terminals was found 2 weeks after TCDD treatment in the forebrain of the TCDD-treated rat, i.e. the central amygdaloid nucleus, field CA3 of the hippocampus, paraventricular hypothalamic nucleus, medial preoptic nucleus, interstitial nucleus of the posterior limb of the anterior commissure, lateral globus pallidus, ventral pallidum and lateral division of the bed nucleus of the stria terminalis. These results demonstrated for the first time a site-specific increased enkephalinergic activity in certain brain regions of the Long-Evans rat. It is suggested that the increased MEK immunoreactivity may act as a compensatory adaptation for the pathophysiological alterations caused by TCDD exposure.
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Affiliation(s)
- Shi-Bin Cheng
- Department of Anatomy, Faculty of Medicine, Kagoshima University, Sakuragaoka 8-35-1, 890-8520, Kagoshima, Japan
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45
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Fokkema MR, Smit EN, Martini IA, Woltil HA, Boersma ER, Muskiet FAJ. Assessment of essential fatty acid and omega3-fatty acid status by measurement of erythrocyte 20:3omega9 (Mead acid), 22:5omega6/20:4omega6 and 22:5omega6/22:6omega3. Prostaglandins Leukot Essent Fatty Acids 2002; 67:345-56. [PMID: 12445496 DOI: 10.1054/plef.2002.0440] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Early suspicion of essential fatty acid deficiency (EFAD) or omega3-deficiency may rather focus on polyunsaturated fatty acid (PUFA) or long-chain PUFA (LCP) analyses than clinical symptoms. We determined cut-off values for biochemical EFAD, omega3-and omega3/22:6omega3 [docosahexaenoic acid (DHA)]-deficiency by measurement of erythrocyte 20:3omega9 (Mead acid), 22:5omega6/20:4omega6 and 22:5omega6/22:6omega3, respectively. METHODS Cut-off values, based on 97.5 percentiles, derived from an apparently healthy omnivorous group (six Dominica breast-fed newborns, 32 breast-fed and 27 formula+LCP-fed Dutch low-birth-weight infants, 31 Jerusalem infants, 33 Dutch 3.5-year-old infants, 69 omnivorous Dutch adults and seven Dominica mothers) and an apparently healthy group with low dietary LCP intake (81 formula-fed Dutch low-birth-weight infants, 12 Dutch vegans). Cut-off values were evaluated by their application in an EFAD suspected group of 108, mostly malnourished, Pakistani children, three pediatric patients with chronic fat-malabsorption (abetal-ipoproteinemia, congenital jejunal and biliary atresia) and one patient with a peroxisomal beta-oxidation disorder. RESULTS Erythrocyte 20:3omega9, 22:5omega6/20:4omega6 and 22:5omega6/22:6omega3 proved age-dependent up to 0.2 years. Cut-off values for ages above 0.2 years were: 0.46mol% 20:3omega9 for EFAD, 0.068mol/mol 22:5omega6/20:4omega6 for omega3-deficiency, 0.22mol/mol 22:5omega6/22:6omega3 for omega3/DHA-marginality and 0.48mol/mol 22:5omega6/22:6omega3 for omega3/DHA-deficiency. Use of RBC 20:3omega9 and 22:5omega6/20:4omega6 cut-off values identified 20.4% of the Pakistani subjects as EFAD+omega3-deficient, 12.9% as EFAD+omega3-sufficient, 38.9% as EFA-sufficient+omega3-deficient and 27.8% as EFA-sufficient+omega3-sufficient. The patient with the peroxisomal disorder was classified as EFA-sufficient, omega3-sufficient (based on RBC 22:5omega6/20:4omega6) and omega3/DHA-deficient (based on RBC 22:5omega6/22:6omega3). The three other pediatric patients were classified as EFAD, omega3-deficient and omega3/DHA-deficient. CONCLUSION Use of the combination of the present cut-off values for EFA, omega3 and omega3/DHA status assessment, as based on 97.5 percentiles, may serve for PUFA supplement intervention until better concepts have emerged.
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MESH Headings
- 8,11,14-Eicosatrienoic Acid/analogs & derivatives
- 8,11,14-Eicosatrienoic Acid/blood
- Bottle Feeding
- Breast Feeding
- Child
- Child, Preschool
- Diet, Vegetarian
- Dominica
- Erythrocytes/chemistry
- Fatty Acids, Essential/blood
- Fatty Acids, Omega-3/blood
- Humans
- Infant
- Infant, Low Birth Weight/blood
- Infant, Newborn
- Israel
- Netherlands
- Pakistan
- Reference Values
- Reproducibility of Results
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Affiliation(s)
- M R Fokkema
- Department of Pathology and Laboratory Medicine, Groningen University Hospital, The Netherlands.
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46
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Seegal RF, Bowers WJ. Consequences and mechanisms of action of fish-borne toxicants: what we do not know and why. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2002; 12:63-68. [PMID: 21782624 DOI: 10.1016/s1382-6689(02)00023-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We summarize and discuss issues that emerged from a workshop entitled 'Human and Animal Neurotoxicology-From Exposure to Great Lakes Pollutants' that was held as part of the May 2000 Annual Meeting of the International Association of Great Lakes Research in Cornwall, Ontario, Canada. The most apparent and distressing finding was the lack of communication that currently exists between scientists of different sub-disciplines-including in vitro and in vivo toxicologists, epidemiologists and risk assessors. Although all participants agreed that integrated, multi-disciplinary research is the only avenue that offers a realistic chance of identifying, characterizing and eventually preventing the adverse consequences of developmental exposure to neurological and reproductive toxicants, there was little consensus on how to achieve this goal. We leave to the readers of this Special Issue of Environmental Toxicology and Pharmacology the daunting task of implementing the greater degree of communication needed to begin to solve problems due to developmental exposure to environmental contaminants.
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Affiliation(s)
- Richard F Seegal
- Wadsworth Center, New York State Department of Health, Box 509, Empire State Plaza, Albany, NY 12201-0509, USA
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Kakeyama M, Sone H, Tohyama C. Changes in expression of NMDA receptor subunit mRNA by perinatal exposure to dioxin. Neuroreport 2001; 12:4009-12. [PMID: 11742229 DOI: 10.1097/00001756-200112210-00031] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Since dioxin and related compounds are suspected of affecting permanently the brain function of offspring of human and experimental animals, effects of perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the expression of rat NMDA receptor NR2A and NR2B subunit mRNA were examined. The mRNA quantification by competitive RT-PCR clearly revealed that TCDD inhibited NR2B mRNA expression and enhanced NR2A mRNA expression in the neocortex and hippocampus on postnatal day (PND) 49, whereas these changes in mRNA expression were not found on PND 5. The results demonstrate for the first time that the perinatal exposure to TCDD can alter the molecular basis of brain of offspring in adulthood.
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Affiliation(s)
- M Kakeyama
- Environmental Health Sciences Division, National Institute for Environmental Studies, (NIES), Onogawa 16-2, Tsukuba 305-8506, Japan
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