17 results on '"Zoeller, R. Thomas"'
Search Results
2. Thyroid-disrupting chemicals: interpreting upstream biomarkers of adverse outcomes
- Author
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Miller, Mark D., Crofton, Kevin M., Rice, Deborah C., and Zoeller, R. Thomas
- Subjects
Biological markers -- Usage ,Biological markers -- Health aspects ,Thyroid diseases -- Risk factors ,Thyroid diseases -- Environmental aspects ,Thyroid hormones -- Physiological aspects ,Thyroid hormones -- Health aspects ,Xenobiotics -- Health aspects - Abstract
BACKGROUND: There is increasing evidence in humans and in experimental animals for a relationship between exposure to specific environmental chemicals and perturbations in levels of critically important thyroid hormones (THs). [...]
- Published
- 2009
3. Why Public Health agencies cannot depend on Good Laboratory Practices as a criterion for selecting data: the case of bisphenol A
- Author
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Myers, John Peterson, vom Saal, Frederick S., Akingbemi, Benson T., Arizono, Koji, Belcher, Scott, Colborn, Theo, Chahoud, Ibrahim, Crain, D. Andrew, Farabollini, Francesca, Guillette, Louis J., Jr., Hassold, Terry, Ho, Shuk-mei, Hunt, Patricia A., Iguchi, Taisen, Jobling, Susan, Kanno, Jun, Laufer, Hans, Marcus, Michele, McLachlan, John A., Nadal, Angel, Oehlmann, Jorg, Olea, Nicolas, Palanza, Paola, Parmigiani, Stefano, Rubin, Beverly S., Schoenfelder, Gilbert, Sonnenschein, Carlos, Soto, Ana M., Talsness, Chris E., Taylor, Julia A., Vandenberg, Laura N., Vandenbergh, John G., Vogel, Sarah, Watson, Cheryl S., Welshons, Wade V., and Zoeller, R. Thomas
- Subjects
Government regulation ,United States. Environmental Protection Agency -- Laws, regulations and rules ,United States. Food and Drug Administration -- Laws, regulations and rules ,European Union. European Food Safety Authority -- Laws, regulations and rules ,Bisphenol-A -- Usage ,Bisphenol-A -- Laws, regulations and rules - Abstract
BACKGROUND: In their safety evaluations of bisphenol A (BPA), the U.S. Food and Drug Administration (FDA) and a counterpart in Europe, the European Food Safety Authority (EFSA), have given special [...]
- Published
- 2009
4. Meeting report: moving upstream--evaluating adverse upstream end points for improved risk assessment and Decision-Making
- Author
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Woodruff, Tracey J., Zeise, Lauren, Axelrad, Daniel A., Guyton, Kathryn Z., Janssen, Sarah, Miller, Mark, Miller, Gregory G., Schwartz, Jackie M., Alexeeff, George, Abderson, Henry, Birnbaum, Linda, Bois, Frederic, Cogliano, Vincent James, Crofton, Kevin, Euling, Susan Y., Foster, Paul M.D., Germolec, Dori R., Gray, Earl, Hattis, Dale B., Kyle, Amy D., Luebke, Robert W., Luster, Michael I., Portier, Chris, Rice, Deborah C., Solomon, Gina, Vandenberg, John, and Zoeller, R. Thomas
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United States. Environmental Protection Agency -- Health policy ,Chemicals -- Health aspects ,Chemicals -- Environmental aspects ,Chronic diseases -- Risk factors - Abstract
BACKGROUND: Assessing adverse effects from environmental chemical exposure is integral to public health policies- Toxicology assays identifying early biological changes from chemical exposure are increasing our ability to evaluate links [...]
- Published
- 2008
5. Polychlorinated biphenyls 105 and 118 form thyroid hormone receptor agonists after cytochrome P4501A1 activation in rat pituitary GH3 cells
- Author
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Gauger, Kelly J., Giera, Stefanie, Sharlin, David S., Bansal, Ruby, Iannacone, Eric, and Zoeller, R. Thomas
- Subjects
Polychlorinated biphenyls -- Research ,Polychlorinated biphenyls -- Health aspects ,Thyroid hormones -- Research ,Thyroid hormones -- Health aspects ,Cytochromes -- Research - Abstract
BACKGROUND: Polychlorinated biphenyls (PCBs) may interfere with thyroid hormone (TH) signaling by reducing TH levels in blood, by exerting direct effects on TH receptors (TRs), or both. OBJECTIVE: Our objective was to identify individual PCBs that directly affect TH signaling by acting on the TR. METHODS: We administered a mixture of six PCB congeners based on their ortho substitution pattern, including PCBs 77 and 126 (non-ortho), PCBs 105 and 118 (mono-ortho), and PCBs 138 and 153 (di-ortho), to pregnant Sprague-Dawley rats from gestational days (G) 6 to 16. This mixture, or various combinations of the components, was also evaluated in a transient transfection system using GH3 cells. RESULTS: The mixture reduced serum TH levels in pregnant rats on G16 but simultaneously up-regulated the expression of malic enzyme in liver. It also functioned as a TR agonist in vitro; however, none of the individual PCB congeners comprising this mixture were active in this system. Using the aryl hydrocarbon receptor (AhR) antagonist [alpha]-naphthoflavone, and the cytochrome P450 (CYP)1A1 antagonist ellipticine, we show that the effect of the mixture on the thyroid hormone response element required AhR and CYP1A1. CONCLUSIONS: We propose that PCB 126 induces CYP1A1 through the AhR in GH3 cells, and that CYP1A1 activates PCB 105 and/or 118 to a form a compound that acts as a TR agonist. These data suggest that some tissues may be especially vulnerable to PCBs interfering directly with TH signaling due to their capacity to express CYP1A1 in response to coplanar PCBs (or other dioxin-like molecules) if sufficient mono-ortho PCBs are present. KEY WORDS: AhR, CYP1A1, endocrine disruption, PCB metabolism, thyroid hormone. Environ Health Perspect 115:1623-1630 (2007). doi:10.1289/ehp.10328 available via http://dx.doi.org/ [Online 16 August 2007], Polychlorinated biphenyls (PCBs) are a class of industrial compounds consisting of paired phenyl rings with various degrees of chlorination (Chana et al. 2002). Although their production was banned in the [...]
- Published
- 2007
6. Evaluation of the U.S. EPA/OSWER preliminary remediation goal for perchlorate in groundwater: focus on exposure to nursing infants
- Author
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Ginsberg, Gary L., Hattis, Dale B., Zoeller, R. Thomas, and Rice, Deborah C.
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Ammonium perchlorate -- Health aspects ,Water, Underground -- Contamination ,Water, Underground -- Health aspects ,Infants -- Health aspects - Abstract
BACKGROUND: Perchlorate is a common contaminant of drinking water and food. It competes with iodide for uptake into the thyroid, thus interfering with thyroid hormone production. The U.S. Environmental Protection [...]
- Published
- 2007
7. Polychlorinated biphenyls (PCBs) exert thyroid hormone-like effects in the fetal rat brain but do not bind to thyroid hormone receptors
- Author
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Gauger, Kelly J., Kato, Yoshihisa, Haraguchi, Koichi, Lehmler, Hans-Joachim, Robertson, Larry W., Bansal, Ruby, and Zoeller, R. Thomas
- Abstract
Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants routinely found in human and animal tissues. Developmental exposure to PCBs is associated with neuropsychologic deficits, which may be related to effects on [...]
- Published
- 2004
8. Maternal polybrominated diphenyl ether (PBDE) exposure and thyroid hormones in maternal and cord sera: the HOME Study, Cincinnati, USA
- Author
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Vuong, Ann M., Webster, Glenys M., Romano, Megan E., Braun, Joseph M., Zoeller, R. Thomas, Hoofnagle, Andrew N., Sjodin, Andreas, Yolton, Kimberly, Lanphear, Bruce P., and Chen, Aimin
- Subjects
Thyroxine -- Research -- Physiological aspects ,Pregnant women -- Health aspects -- Research ,Environmental issues ,Health - Abstract
BACKGROUND: Polybrominated diphenyl ethers (PBDEs) reduce blood concentrations of thyroid hormones in laboratory animals, but it is unclear whether PBDEs disrupt thyroid hormones in pregnant women or newborn infants. OBJECTIVES: We investigated the relationship between maternal PBDE levels and thyroid hormone concentrations in maternal and cord sera. Methods: we used data from the Health Outcomes and Measures of the Environment (HOME) Study, a prospective birth cohort of 389 pregnant women in Cincinnati, Ohio, who were enrolled from 2003 through 2006 and delivered singleton infants. Maternal serum PBDE concentrations were measured at enrollment (16 ± 3 weeks of gestation). Thyroid hormone concentrations were measured in maternal serum at enrollment (n = 187) and in cord serum samples (n = 256). RESULTS: Median maternal serum concentrations of BDEs 28 and 47 were 1.0 and 19.1 ng/g lipid, respectively. A 10-fold increase in BDEs 28 and 47 concentrations was associated with a 0.85-µg/dL [95% confidence interval (CI): 0.05, 1.64] and 0.82-µg/dL (95% CI: 0.12, 1.51) increase in maternal total thyroxine concentrations ([TT.sub.4]), respectively. Both congeners were also positively associated with maternal free thyroxine ([FT.sub.4]). We also observed positive associations between BDE-47 and maternal total and free triiodothyronine ([TT.sub.4] and [FT.sub.3]). A 10-fold increase in BDE-28 was associated with elevated [FT.sub.3] concentrations (β = 0.14 µg/mL; 95% CI: 0.02, 0.26). In contrast, maternal PBDE levels were not associated with thyroid hormone concentrations in cord serum. CONCLUSIONS: These findings suggest that maternal PBDE exposure, particularly BDEs 28 and 47, are associated with maternal concentrations of [T.sub.4] and [T.sub.3] during pregnancy. http://dx.doi.org/10.1289/ehp.1408996, Introduction Polybrominated diphenyl ethers (PBDEs), synthetic flame retardants, have been used in the manufacture of consumer products, including furniture foam, carpet padding, and electronics. Because they are semivolatile and are [...]
- Published
- 2015
- Full Text
- View/download PDF
9. The impact of endocrine disruption: a consensus statement on the state of the science
- Author
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Bergman, Ake, Heindel, Jerrold J., Kasten, Tim, Kidd, Karen A., Jobling, Susan, Neira, Maria, Zoeller, R. Thomas, Becher, Georg, Bjerregaard, Poul, Bornman, Riana, Brandt, Ingvar, Kortenkamp, Andreas, Muir, Derek, Drisse, Marie-Noel Brune, Ochieng, Roseline, Skakkebaek, Niels E., Bylehn, Agneta Sunden, Iguchi, Taisen, Toppari, Jorma, and Woodruff, Tracey J.
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Environmental health -- Research ,Endocrine disruptors -- Health aspects ,Endocrine gland diseases -- Research ,Environmental issues ,Health - Abstract
In 2002, the joint International Programme on Chemical Safety (IPCS) of the World Health Organization (WHO), the United Nations Environment Programme (UNEP), and the International Labour Organisation (ILO) published a [...]
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- 2013
- Full Text
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10. Scientific issues relevant to setting regulatory criteria to identify endocrine-disrupting substances in the European Union
- Author
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Bourguignon, Jean-Pierre, Demeneix, Barbara, Ivell, Richard, Panzica, Giancarlo, Kortenkamp, Andreas, and Zoeller, R. Thomas
- Abstract
Background: Endocrine disruptors (EDs) are defined by the World Health Organization (WHO) as exogenous compounds or mixtures that alter function(s) of the endocrine system and consequently cause adverse effects in an intact organism, or its progeny, or (sub)populations. European regulations on pesticides, biocides, cosmetics, and industrial chemicals require the European Commission to establish scientific criteria to define EDs.Objectives: We address the scientific relevance of four options for the identification of EDs proposed by the European Commission.Discussion: Option 1, which does not define EDs and leads to using interim criteria unrelated to the WHO definition of EDs, is not relevant. Options 2 and 3 rely on the WHO definition of EDs, which is widely accepted by the scientific community, with option 3 introducing additional categories based on the strength of evidence (suspected EDs and endocrine-active substances). Option 4 adds potency to the WHO definition, as a decision criterion. We argue that potency is dependent on the adverse effect considered and is scientifically ambiguous, and note that potency is not used as a criterion to define other particularly hazardous substances such as carcinogens and reproductive toxicants. The use of potency requires a context that goes beyond hazard identification and corresponds to risk characterization, in which potency (or, more relevantly, the dose–response function) is combined with exposure levels.Conclusions: There is scientific agreement regarding the adequacy of the WHO definition of EDs. The potency concept is not relevant to the identification of particularly serious hazards such as EDs. As is common practice for carcinogens, mutagens, and reproductive toxicants, a multi-level classification of ED based on the WHO definition, and not considering potency, would be relevant (corresponding to option 3 proposed by the European Commission).
- Published
- 2016
11. The florence statement on triclosan and triclocarban
- Author
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Halden, Rolf U., Lindeman, Avery E., Aiello, Allison E., Andrews, David, Arnold, William A., Fair, Patricia, Fuoco, Rebecca E., Geer, Laura A., Johnson, Paula I., Lohmann, Rainer, McNeill, Kristopher, Sacks, Victoria P., Schettler, Ted, Weber, Roland, Zoeller, R. Thomas, and Blum, Arlene
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Triclosan -- Research ,Ecosystems -- Research ,Triclocarban -- Research ,Environmental issues ,Health - Abstract
The Florence Statement on Triclosan and Triclocarban documents a consensus of more than 200 scientists and medical professionals on the hazards of and lack of demonstrated benefit from common uses of triclosan and triclocarban. These chemicals may be used in thousands of personal care and consumer products as well as in building materials. Based on extensive peer-reviewed research, this statement concludes that triclosan and triclocarban are environmentally persistent endocrine disruptors that bioaccumulate in and are toxic to aquatic and other organisms. Evidence of other hazards to humans and ecosystems from triclosan and triclocarban is presented along with recommendations intended to prevent future harm from triclosan, triclocarban, and antimicrobial substances with similar properties and effects. Because antimicrobials can have unintended adverse health and environmental impacts, they should only be used when they provide an evidence-based health benefit. Greater transparency is needed in product formulations, and before an antimicrobial is incorporated into a product, the long-term health and ecological impacts should be evaluated. https://doi.org/10.1289/EHP1788., Introduction In September 2016, the U.S. Food and Drug Administration (FDA) banned nineteen antimicrobial ingredients, including triclosan and triclocarban, in over-the-counter consumer antiseptic wash products based on insufficient evidence demonstrating [...]
- Published
- 2017
- Full Text
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12. Scientific Issues Relevant to Setting Regulatory Criteria to Identify Endocrine-Disrupting Substances in the European Union.
- Author
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Slama, Rémy, Bourguignon, Jean-Pierre, Demeneix, Barbara, Ivell, Richard, Panzica, Giancarlo, Kortenkamp, Andreas, and Zoeller, R. Thomas
- Subjects
HAZARDOUS substance laws ,CARCINOGENS ,COSMETICS ,DOSE-response relationship in biochemistry ,ENDOCRINE diseases ,INDUSTRIES ,PESTICIDES ,ENVIRONMENTAL exposure - Abstract
BACKGROUND: Endocrine disruptors (EDs) are defined by the World Health Organization (WHO) as exogenous compounds or mixtures that alter function(s) of the endocrine system and consequently cause adverse effects in an intact organism, or its progeny, or (sub)populations. European regulations on pesticides, biocides, cosmetics, and industrial chemicals require the European Commission to establish scientific criteria to define EDs. OBJECTIVES: We address the scientific relevance of four options for the identification of EDs proposed by the European Commission. DISCUSSION: Option 1, which does not define EDs and leads to using interim criteria unrelated to the WHO definition of EDs, is not relevant. Options 2 and 3 rely on the WHO definition of EDs, which is widely accepted by the scientific community, with option 3 introducing additional categories based on the strength of evidence (suspected EDs and endocrine-active substances). Option 4 adds potency to the WHO definition, as a decision criterion. We argue that potency is dependent on the adverse effect considered and is scientifically ambiguous, and note that potency is not used as a criterion to define other particularly hazardous substances such as carcinogens and reproductive toxicants. The use of potency requires a context that goes beyond hazard identification and corresponds to risk characterization, in which potency (or, more relevantly, the dose -- response function) is combined with exposure levels. CONCLUSIONS: There is scientific agreement regarding the adequacy of the WHO definition of EDs. The potency concept is not relevant to the identification of particularly serious hazards such as EDs. As is common practice for carcinogens, mutagens, and reproductive toxicants, a multi-level classification of ED based on the WHO definition, and not considering potency, would be relevant (corresponding to option 3 proposed by the European Commission). CITATION: Slama R, Bourguignon JP, Demeneix B, Ivell R, Panzica G, Kortenkamp A, Zoeller RT. 2016. Scientific issues relevant to setting regulatory criteria to identify endocrine disrupting substances in the European Union. Environ Health Perspect 124:1497-1503; http://dx.doi.org/10.1289/EHP217 [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
13. Hypothyroxinemia: Zoeller's response
- Author
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Zoeller, R. Thomas
- Abstract
Soldin addresses an important issue that was not fully developed in my editorial (Zoeller 2003a), specifically, the description of thyroid status in experimental animals designed to model human conditions. There [...]
- Published
- 2004
14. Thyroid toxicology and brain development: should we think differently?
- Author
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Zoeller, R. Thomas
- Subjects
Brain - Abstract
Thyroid hormone (TH) is essential for normal brain development. The simplicity of this statement, however, dramatically understates the complexity of the issues confronting us as we develop ways to identify [...]
- Published
- 2003
15. Polychiorinated Biphenyls 105 and 118 Form Thyroid Hormone Receptor Agonists after Cytochrome P4501A1 Activation in Rat Pituitary GH3 Cells.
- Author
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Kelly J. Gauger, Giera, Stefanie, Sharlin, David S., Bansal, Ruby, Iannacone, Eric, and Zoeller, R. Thomas
- Subjects
POLYCHLORINATED biphenyls ,THYROID hormones ,RATS ,HORMONE receptors ,DERIVATIZATION ,CYTOCHROME P-450 - Abstract
BACKGROUND: Polychlorinated biphenyls (PCBs) may interfere with thyroid hormone (TH) signaling by reducing TH levels in blood, by exerting direct effects on TH receptors (TRs), or both. OBJECTIVE: Our objective was to identify individual PCBs that directly affect TH signaling by acting on the TR. METHODS: We administered a mixture of six PCB congeners based on their ortho substitution pattern, including PCBs 77 and 126 (non-ortho), PCBs 105 and 118 (mono-ortho), and PCBs 138 and 153 (di-ortho), to pregnant Sprague-Dawley rats from gestational days (G) 6 to 16. This mixture, or various combinations of the components, was also evaluated in a transient transfection system using GH3 cells. RESULTS: The mixture reduced serum TH levels in pregnant rats on G16 but simultaneously up-regulated the expression of malic enzyme in liver. It also functioned as a TR agonist in vitro; however, none of the individual PCB congeners comprising this mixture were active in this system. Using the aryl hydrocarbon receptor (AhR) antagonist cc-naphthoflavone, and the cytochrome P450 (CYP)1A1 antagonist ellipticine, we show that the effect of the mixture on the thyroid hormone response element required AhR and CYP1A1. CONCLUSIONS: We propose that PCB 126 induces CYP1A1 through the AhR in GH3 cells, and that CYP1A1 activates PCB 105 and/or 118 to a form a compound that acts as a TR agonist. These data suggest that some tissues may be especially vulnerable to PCBs interfering directly with TH signaling due to their capacity to express CYP1A1 in response to coplanar PCBs (or other dioxin-like molecules) if sufficient mono-ortho PCBs are present. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
16. The Conflict between Regulatory Agencies over the 20,000-Fold Lowering of the Tolerable Daily Intake (TDI) for Bisphenol A (BPA) by the European Food Safety Authority (EFSA).
- Author
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Vom Saal FS, Antoniou M, Belcher SM, Bergman A, Bhandari RK, Birnbaum LS, Cohen A, Collins TJ, Demeneix B, Fine AM, Flaws JA, Gayrard V, Goodson WH 3rd, Gore AC, Heindel JJ, Hunt PA, Iguchi T, Kassotis CD, Kortenkamp A, Mesnage R, Muncke J, Myers JP, Nadal A, Newbold RR, Padmanabhan V, Palanza P, Palma Z, Parmigiani S, Patrick L, Prins GS, Rosenfeld CS, Skakkebaek NE, Sonnenschein C, Soto AM, Swan SH, Taylor JA, Toutain PL, von Hippel FA, Welshons WV, Zalko D, and Zoeller RT
- Subjects
- Humans, Food Safety, No-Observed-Adverse-Effect Level, Systematic Reviews as Topic, Benzhydryl Compounds, Phenols
- Abstract
Background: The European Food Safety Authority (EFSA) recommended lowering their estimated tolerable daily intake (TDI) for bisphenol A (BPA) 20,000-fold to 0.2 ng / kg body weight ( BW ) / day . BPA is an extensively studied high production volume endocrine disrupting chemical (EDC) associated with a vast array of diseases. Prior risk assessments of BPA by EFSA as well as the US Food and Drug Administration (FDA) have relied on industry-funded studies conducted under good laboratory practice protocols (GLP) requiring guideline end points and detailed record keeping, while also claiming to examine (but rejecting) thousands of published findings by academic scientists. Guideline protocols initially formalized in the mid-twentieth century are still used by many regulatory agencies. EFSA used a 21st century approach in its reassessment of BPA and conducted a transparent, but time-limited, systematic review that included both guideline and academic research. The German Federal Institute for Risk Assessment (BfR) opposed EFSA's revision of the TDI for BPA., Objectives: We identify the flaws in the assumptions that the German BfR, as well as the FDA, have used to justify maintaining the TDI for BPA at levels above what a vast amount of academic research shows to cause harm. We argue that regulatory agencies need to incorporate 21st century science into chemical hazard identifications using the CLARITY-BPA (Consortium Linking Academic and Regulatory Insights on BPA Toxicity) nonguideline academic studies in a collaborative government-academic program model., Discussion: We strongly endorse EFSA's revised TDI for BPA and support the European Commission's (EC) apparent acceptance of this updated BPA risk assessment. We discuss challenges to current chemical risk assessment assumptions about EDCs that need to be addressed by regulatory agencies to, in our opinion, become truly protective of public health. Addressing these challenges will hopefully result in BPA, and eventually other structurally similar bisphenols (called regrettable substitutions) for which there are known adverse effects, being eliminated from all food-related and many other uses in the EU and elsewhere. https://doi.org/10.1289/EHP13812.
- Published
- 2024
- Full Text
- View/download PDF
17. Project TENDR: Targeting Environmental Neuro-Developmental Risks The TENDR Consensus Statement.
- Author
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Bennett D, Bellinger DC, Birnbaum LS, Bradman A, Chen A, Cory-Slechta DA, Engel SM, Fallin MD, Halladay A, Hauser R, Hertz-Picciotto I, Kwiatkowski CF, Lanphear BP, Marquez E, Marty M, McPartland J, Newschaffer CJ, Payne-Sturges D, Patisaul HB, Perera FP, Ritz B, Sass J, Schantz SL, Webster TF, Whyatt RM, Woodruff TJ, Zoeller RT, Anderko L, Campbell C, Conry JA, DeNicola N, Gould RM, Hirtz D, Huffling K, Landrigan PJ, Lavin A, Miller M, Mitchell MA, Rubin L, Schettler T, Tran HL, Acosta A, Brody C, Miller E, Miller P, Swanson M, and Witherspoon NO
- Subjects
- Child, Humans, Risk Assessment methods, United States, Developmental Disabilities prevention & control, Environmental Exposure prevention & control, Environmental Health methods, Neurodevelopmental Disorders prevention & control, Public Health methods
- Published
- 2016
- Full Text
- View/download PDF
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