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1.
Behav Brain Funct ; 14(1): 3, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29415737

RESUMO

The original version of this article [1] unfortunately contained an error which has since been acknowledged in this Correction article. The URL link in the Reference 19 was broken and it needs to be replaced with the active link given below.

2.
World J Psychiatry ; 14(1): 159-178, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38327893

RESUMO

BACKGROUND: Unhealthy maternal diet leads to heavy metal exposures from the consumption of ultra-processed foods that may impact gene behavior across generations, creating conditions for the neurodevelopmental disorders known as autism and attention deficit/hyperactivity disorder (ADHD). Children with these disorders have difficulty metabolizing and excreting heavy metals from their bloodstream, and the severity of their symptoms correlates with the heavy metal levels measured in their blood. Psychiatrists may play a key role in helping parents reduce their ultra-processed food and dietary heavy metal intake by providing access to effective nutritional epigenetics education. AIM: To test the efficacy of nutritional epigenetics instruction in reducing parental ultra-processed food intake. METHODS: The study utilized a semi-randomized test and control group pretest-posttest pilot study design with participants recruited from parents having a learning-disabled child with autism or ADHD. Twenty-two parents who met the inclusion criteria were randomly selected to serve in the test (n = 11) or control (n = 11) group. The test group participated in the six-week online nutritional epigenetics tutorial, while the control group did not. The efficacy of the nutritional epigenetics instruction was determined by measuring changes in parent diet and attitude using data derived from an online diet survey administered to the participants during the pre and post intervention periods. Diet intake scores were derived for both ultra-processed and whole/organic foods. Paired sample t-tests were conducted to determine any differences in mean diet scores within each group. RESULTS: There was a significant difference in the diet scores of the test group between the pre- and post-intervention periods. The parents in the test group significantly reduced their intake of ultra-processed foods with a pre-intervention diet score of 70 (mean = 5.385, SD = 2.534) and a post-intervention diet score of 113 (mean = 8.692, SD = 1.750) and the paired t-test analysis showing a significance of P < 0.001. The test group also significantly increased their consumption of whole and/or organic foods with a pre-intervention diet score of 100 (mean = 5.882, SD = 2.472) and post-intervention diet score of 121 (mean = 7.118, SD = 2.390) and the paired t-test analysis showing a significance of P < 0.05. CONCLUSION: Here we show nutritional epigenetics education can be used to reduce ultra-processed food intake and improve attitude among parents having learning-disabled children with autism or ADHD.

3.
World J Clin Pediatr ; 12(2): 25-37, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-37034430

RESUMO

In the United States, schools offer special education services to children who are diagnosed with a learning or neurodevelopmental disorder and have difficulty meeting their learning goals. Pediatricians may play a key role in helping children access special education services. The number of children ages 6-21 in the United States receiving special education services increased 10.4% from 2006 to 2021. Children receiving special education services under the autism category increased 242% during the same period. The demand for special education services for children under the developmental delay and other health impaired categories increased by 184% and 83% respectively. Although student enrollment in American schools has remained stable since 2006, the percentage distribution of children receiving special education services nearly tripled for the autism category and quadrupled for the developmental delay category by 2021. Allowable heavy metal residues remain persistent in the American food supply due to food ingredient manufacturing processes. Numerous clinical trial data indicate heavy metal exposures and poor diet are the primary epigenetic factors responsible for the autism and attention deficit hyperactivity disorder epidemics. Dietary heavy metal exposures, especially inorganic mercury and lead may impact gene behavior across generations. In 2021, the United States Congress found heavy metal residues problematic in the American food supply but took no legislative action. Mandatory health warning labels on select foods may be the only way to reduce dietary heavy metal exposures and improve child learning across generations.

4.
World J Methodol ; 11(4): 144-159, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34322366

RESUMO

Pre-natal and post-natal chemical exposures and co-exposures from a variety of sources including contaminated air, water, soil, and food are common and associated with poorer birth and child health outcomes. Poor diet is a contributing factor in the development of child behavioral disorders. Child behavior and learning can be adversely impacted when gene expression is altered by dietary transcription factors such as zinc insufficiency or deficiency or by exposure to toxic substances permitted in our food supply such as mercury, lead, or organophosphate pesticide residue. Children with autism spectrum disorder and attention deficit hyperactivity disorders exhibit decreased or impaired PON1 gene activity which is needed by the body to metabolize and excrete neurotoxic organophosphate pesticides. In this current review we present an updated macroepigenetic model that explains how dietary inorganic mercury and lead exposures from unhealthy diet may lead to elevated blood mercury and/or lead levels and the development of symptoms associated with the autism and attention deficit-hyperactivity disorders. PON1 gene activity may be suppressed by inadequate dietary calcium, selenium, and fatty acid intake or exposures to lead or mercury. The model may assist clinicians in diagnosing and treating the symptoms associated with these childhood neurodevelopmental disorders. Recommendations for future research are provided based on the updated model and review of recently published literature.

5.
J Intellect Dev Disabil ; 35(2): 121-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20560701

RESUMO

Given established scientific knowledge, protecting children from neurotoxic exposures from the earliest stages of fetal development is clearly an essential public health measure. By reducing environmental factors that may lead to learning and developmental disorders, we will create a healthier environment in which all children can reach and maintain their full potential. (Gilbert, 2008 ).


Assuntos
Proteção da Criança , Deficiências do Desenvolvimento/etiologia , Poluentes Ambientais/efeitos adversos , Guias como Assunto , Política Pública , Criança , Exposição Ambiental , Saúde Ambiental , Humanos , Deficiências da Aprendizagem/etiologia , Saúde Pública , Medição de Risco , Ciência
6.
EXS ; 99: 1-35, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19157056

RESUMO

Knowledge of the toxic and healing properties of plants, animals, and minerals has shaped civilization for millennia. The foundations of modern toxicology are built upon the significant milestones and discoveries of serendipity and crude experimentation. Throughout the ages, toxicological science has provided information that has shaped and guided society. This chapter examines the development of the discipline of toxicology and its influence on civilization by highlighting significant milestones and discoveries related to toxicology. The examples shed light on the beginnings of toxicology, as well as examine lessons learned and re-learned. This chapter also examines how toxicology and the toxicologist have interacted with other scientific and cultural disciplines, including religion, politics, and the government. Toxicology has evolved to a true scientific discipline with its own dedicated scientists, educational institutes, sub-disciplines, professional societies, and journals. It now stands as its own entity while traversing such fields as chemistry, physiology, pharmacology, and molecular biology. We invite you to join us on a path of discovery and to offer our suggestions as to what are the most significant milestones and discoveries in toxicology. Additional information is available on the history section of Toxipedia (www.toxipedia.org).


Assuntos
Toxicologia/história , Toxicologia/métodos , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , História Antiga , História Medieval , Toxicologia/tendências
7.
Behav Brain Funct ; 5: 44, 2009 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-19860886

RESUMO

Among dietary factors, learning and behavior are influenced not only by nutrients, but also by exposure to toxic food contaminants such as mercury that can disrupt metabolic processes and alter neuronal plasticity. Neurons lacking in plasticity are a factor in neurodevelopmental disorders such as autism and mental retardation. Essential nutrients help maintain normal neuronal plasticity. Nutritional deficiencies, including deficiencies in the long chain polyunsaturated fatty acids eicosapentaenoic acid and docosahexaenoic acid, the amino acid methionine, and the trace minerals zinc and selenium, have been shown to influence neuronal function and produce defects in neuronal plasticity, as well as impact behavior in children with attention deficit hyperactivity disorder. Nutritional deficiencies and mercury exposure have been shown to alter neuronal function and increase oxidative stress among children with autism. These dietary factors may be directly related to the development of behavior disorders and learning disabilities. Mercury, either individually or in concert with other factors, may be harmful if ingested in above average amounts or by sensitive individuals. High fructose corn syrup has been shown to contain trace amounts of mercury as a result of some manufacturing processes, and its consumption can also lead to zinc loss. Consumption of certain artificial food color additives has also been shown to lead to zinc deficiency. Dietary zinc is essential for maintaining the metabolic processes required for mercury elimination. Since high fructose corn syrup and artificial food color additives are common ingredients in many foodstuffs, their consumption should be considered in those individuals with nutritional deficits such as zinc deficiency or who are allergic or sensitive to the effects of mercury or unable to effectively metabolize and eliminate it from the body.

8.
Rev Environ Contam Toxicol ; 201: 1-39, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19484587

RESUMO

The health risks to babies from pollutants in house dust may be 100 times greater than for adults. The young ingest more dust and are up to ten times more vulnerable to such exposures. House dust is the main exposure source for infants to allergens, lead, and PBDEs, as well as a major source of exposure to pesticides, PAHs, Gram-negative bacteria, arsenic, cadmium, chromium, phthalates, phenols, and other EDCs, mutagens, and carcinogens. Median or upper percentile concentrations in house dust of lead and several pesticides and PAHs may exceed health-based standards in North America. Early contact with pollutants among the very young is associated with higher rates of chronic illness such as asthma, loss of intelligence, ADHD, and cancer in children and adults. The potential of infants, who live in areas with soil contaminated by automotive and industrial emissions, can be given more protection by improved home cleaning and hand washing. Babies who live in houses built before 1978 have a prospective need for protection against lead exposures; homes built before 1940 have even higher lead exposure risks. The concentration of pollutants in house dust may be 2-32 times higher than that found in the soil near a house. Reducing infant exposures, at this critical time in their development, may reduce lifetime health costs, improve early learning, and increase adult productivity. Some interventions show a very rapid payback. Two large studies provide evidence that home visits to reduce the exposure of children with poorly controlled asthma triggers may return more than 100% on investment in 1 yr in reduced health costs. The tools provided to families during home visits, designed to reduce dust exposures, included vacuum cleaners with dirt finders and HEPA filtration, allergy control bedding covers, high-quality door mats, and HEPA air filters. Infants receive their highest exposure to pollutants in dust at home, where they spend the most time, and where the family has the most mitigation control. Normal vacuum cleaning allows deep dust to build up in carpets where it can be brought to the surface and become airborne as a result of activity on the carpet. Vacuums with dirt finders allow families to use the three-spot test to monitor deep dust, which can reinforce good cleaning habits. Motivated families that receive home visits from trained outreach workers can monitor and reduce dust exposures by 90% or more in 1 wk. The cost of such visits is low considering the reduction of risks achieved. Improved home cleaning is one of the first results observed among families who receive home visits from MHEs and CHWs. We believe that proven intervention methods can reduce the exposure of infants to pollutants in house dust, while recognizing that much remains to be learned about improving the effectiveness of such methods.


Assuntos
Poluição do Ar em Ambientes Fechados/prevenção & controle , Poeira/análise , Exposição Ambiental/prevenção & controle , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Éteres Difenil Halogenados/análise , Humanos , Lactente , Metais/análise , Praguicidas/análise , Bifenilos Policlorados/análise
9.
Neurotoxicology ; 29(5): 883-90, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18501430

RESUMO

Neurotoxicology is entering a new phase in how it views and practices risk assessment. Perhaps more than any of the other disciplines that comprise the science of toxicology, it has been compelled to consider a daunting array of factors other than those directly coupled to chemical and dose, and the age and sex of the subject population. In epidemiological investigations, researchers are increasingly cognizant of the problems introduced by allegedly controlling for variables classified as confounders or covariates. In essence, they reason, the consequence is blurring or even concealing interactions of exposure with modifiers such as the individual's social ecology. Other researchers question the traditional practice of relying on values such as NOAELs when they are abstracted from a biological entity that in reality represents a multiplicity of intertwined systems. Although neurotoxicologists have come to recognize the complexities of assessing risk in all its dimensions, they still face the challenge of communicating this view to the health professions at large.


Assuntos
Medição de Risco/tendências , Toxicologia/tendências , Animais , Humanos , Medição de Risco/métodos , Toxicologia/métodos
10.
Neurotoxicology ; 69: 181-186, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29128313

RESUMO

Outdated federal and state occupational lead standards leave workers and their families vulnerable to the adverse effects of lead. Standards should be updated to reflect the best available scientific and medical evidence, which documents harm to multiple organ systems even at low levels of exposure. This commentary will review the inadequacies of existing policies, highlight susceptible populations, and briefly summarize state revision efforts to date. Federal policies must be strengthened to protect all workers and their families from this well-documented hazard.


Assuntos
Política de Saúde/legislação & jurisprudência , Nível de Saúde , Chumbo/efeitos adversos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/legislação & jurisprudência , Recursos Humanos/legislação & jurisprudência , Política de Saúde/tendências , Humanos , Exposição Ocupacional/prevenção & controle , Recursos Humanos/tendências
11.
Environ Health Perspect ; 114(10): 1626-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17035155

RESUMO

BACKGROUND: Community-based research often involves additional ethical, legal, and social considerations beyond those of the specific individuals involved in the study. The traditional institutional review board (IRB) typically focuses on protecting the rights and ensuring the safety of the individuals involved. For projects involving community members, IRBs should be more sensitive to issues related to the broader community concerns. OBJECTIVES: The objective of this article is to discuss the concept of community-based participatory research and the shortcomings of the traditional IRBs in dealing with ethical issues associated with broader community concerns such as implications for family members, neighborhood groups, and local businesses. I examine the rationale and benefits for expanding the roles and responsibilities of review boards related to community-based issues. DISCUSSION: I propose the development of environmental health and community review boards (EHCRBs) that combine the fundamental responsibilities and ethical concept of the traditional review boards with an expanded ethical construct of dignity, veracity, sustainability, and justice, with an added emphasis on community. CONCLUSIONS: Only by acknowledging the needs of and working with the community can we ensure ethically based and socially responsible research. An EHCRB will allow researchers and community members to more fully address their mutual interest in conducting scientific, ethical, and socially responsible research.


Assuntos
Saúde Ambiental , Comitês de Ética em Pesquisa , Ética em Pesquisa , Humanos
12.
Neurotoxicology ; 27(5): 693-701, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16889836

RESUMO

Fifteen years ago, in 1991, the U.S. Centers for Disease Control and Prevention (CDC) established 10 microg/dL as the lowest level of concern for children's blood lead levels. This value is extremely important because, historically, policy makers and public health officials generally have acted to remove sources of lead exposure only after the CDC's level of concern had been exceeded. A growing body of evidence, however, reveals that blood lead levels below 10 microg/dL may impair neurobehavioral development. There is now sufficient and compelling scientific evidence for the CDC to lower the blood lead action level in children. This review argues that a level of 2 microg/dL is a useful and feasible replacement. Although it can be argued, in turn, that no threshold for the health effects of lead is demonstrable, analytically a blood level of 2 microg/dL is readily and accurately measured and provides a benchmark for successful prevention. Lowering the level of concern would encourage and accelerate the investments needed to ensure that children are protected from lead exposure in their homes, schools, and play settings. Such a program would also offer economic advantages because of the coupling between lead, educational attainment, earnings and anti-social conduct. By lowering the blood action level, CDC will promote policies and initiatives designed to further reduce children's exposure to this potent developmental neurotoxicant.


Assuntos
Exposição Ambiental , Intoxicação por Chumbo , Chumbo/sangue , Adolescente , Centers for Disease Control and Prevention, U.S./normas , Criança , Pré-Escolar , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/fisiopatologia , História do Século XIX , História do Século XX , Humanos , Intoxicação por Chumbo/diagnóstico , Intoxicação por Chumbo/história , Intoxicação por Chumbo/fisiopatologia , Estados Unidos
13.
Toxicol Sci ; 87(1): 11-4, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15976187

RESUMO

There is no doubt that participants in the Conflict of Interest (COI) Workshop at the Society of Toxicology (SOT) 2005 Annual Meeting (New Orleans, 6-10 March 2005) engaged in a vigorous and useful exchange of diverse ideas and viewpoints. While there was consensus on the value and interest of this Workshop, there was less consensus and more controversy over many of the issues discussed during the Workshop, which included the distinction between bias and conflict, the success or failure of policies of disclosure, whether waivers should or should not be granted to conflicted individuals in order to seat a "balanced" committee with appropriate expertise, whether conflicted individuals retain the ability to recognize their own conflict, and more. The discussion left no doubt, however, that conflict of interest will remain an important and controversial issue in the scientific community for some time to come.


Assuntos
Conflito de Interesses , Viés , Indústria Farmacêutica , Humanos , Princípios Morais , Ciência
14.
Neurotoxicology ; 26(4): 521-30, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16112318

RESUMO

A convergence of issues suggests that protecting child health is not so much a matter of research, but rather a matter of policy and advocacy. First, we have well-articulated views of a vision for child health. Second, we have experience and toxicological research findings demonstrating the adverse health effects of hazardous chemicals on children and recognize that children are more sensitive than adults to chemical exposures. Results from toxicology research have motivated many regulatory and legal actions, and public policy decisions, including the banning of some pesticides, reducing exposures in the workplace, and lowering of acceptable blood lead levels in children. We also know that childhood disabilities from chemical exposure during developmental are often not treatable and therefore must be prevented. Finally, we have an increasingly well-defined framework for discussing social and ethical responsibility to our children. New discoveries in the basic biological and toxicological sciences have challenged our bioethical thinking and societal decision-making. This paper will explore the ethical, legal, and social issues raised by the toxicological sciences first by examining some hard lesson learned about childhood effects of chemicals and then by examining the difficult policy and research decisions that must be made as we address our need for additional information about the health effects of chemicals on adults and children and the impact of having this information. The precautionary principle will be considered as an alternative decision-making approach as well as exploring the concept of the citizen toxicologist (CT). As Garrett Hardin pointed out many years ago, the problems we face often have no technical solutions, but rather require a policy-based approach. This paper will be of interest to the public and health professionals concerned about the broader impact of toxicological research on bioethical and societal decision-making.


Assuntos
Proteção da Criança/ética , Criança , Política Pública , Toxicologia/ética , Pré-Escolar , Tomada de Decisões , Humanos , Lactente , Recém-Nascido
15.
Integr Mol Med ; 2(3)2015.
Artigo em Inglês | MEDLINE | ID: mdl-33889422

RESUMO

BACKGROUND: The goals of the study were (1) to determine the impact of inorganic mercury exposure on glucose homeostasis; and (2) to evaluate the effectiveness of two community-based interventions in promoting dietary changes among American Indian college students to reduce risk factors for Type-2 Diabetes including fasting glucose, insulin, and mercury levels, weight, and body mass index. METHODS: To accomplish goal one, the National Health and Nutrition Examination Survey (NHANES) dataset was analyzed using a previously published method to determine if there is a relationship between inorganic blood mercury and fasting glucose. To accomplish goal two, ten college students were recruited and randomly assigned to a group receiving the online macroepigenetics nutrition course and the support group for eliminating corn sweeteners. Participants in both groups were assessed for diet patterns, weight, body mass index (BMI), fasting glucose, insulin, and mercury levels. The interventions were implemented over a 10-week period. RESULTS: Analysis of the NHANES data (n=16,232) determined a direct relationship between inorganic mercury in blood and fasting glucose levels (p<0.001). The participants who took the online macroepigenetics nutrition intervention course significantly improved their diets (p<0.01), and fasting blood glucose levels (p<0.01) while having lower levels of inorganic mercury in their blood compared to the subjects in the group who eliminated corn sweeteners from their diet and participated in the support group. The trend in lower blood inorganic mercury was strong with p=0.052. The participants in the support group who eliminated corn sweeteners from their diet achieved significant weight loss (p<0.01) and reduced their body mass index (p<0.01). CONCLUSION: Total blood mercury levels may be influenced by dietary intake of highly processed foods and lower inorganic mercury levels are associated with lower fasting glucose levels. Alternative community-based interventions emphasizing the role food ingredients and toxic substances play in gene modulation and the development of diseases can result in significant dietary improvements and reductions in risk factors associated with type-2 diabetes. A healthier diet can be promoted among community members using a novel online nutrition course. Consumption of corn sweeteners may be a risk factor in the development of obesity.

16.
Hum Exp Toxicol ; 31(3): 207-14, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21071551

RESUMO

The World Library of Toxicology, Chemical Safety, and Environmental Health, commonly referred to as the World Library of Toxicology (WLT), is a multilingual online portal of links to key global resources, representing a host of individual countries and multilateral organizations. The Site is designed as a network of, and gateway to, toxicological information and activities from around the world. It is built on a Wiki platform by a roster of Country Correspondents, with the aim of efficiently exchanging information and stimulating collaboration among colleagues, and building capacity, with the ultimate objective of serving as a tool to help improve global public health. The WLT was publicly launched on September 7, 2009, at the Seventh Congress of Toxicology in Developing Countries (CTDC-VII) in Sun City, South Africa.


Assuntos
Bases de Dados Factuais , Saúde Ambiental , Bibliotecas Médicas , Toxicologia , Xenobióticos/toxicidade , Saúde Global , Humanos , Cooperação Internacional , Internet
17.
Neurotoxicology ; 33(4): 805-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22037493

RESUMO

This summary provides a synopsis of talks included in a symposium entitled "Current Needs and Future Directions of Occupational Safety and Heath in a Globalized World". The purpose of the symposium was to (1) highlight national and international agencies with occupational health related activities; (2) address electronic (e-)waste issues in developing countries where exposures are secondary to the handling and scavenging of scrap; and (3) discuss the effects of hazardous materials, such as polycyclic aromatic hydrocarbon (PAH) and tobacco smoke on child intelligence quotient (IQ) in developing countries.


Assuntos
Resíduo Eletrônico/efeitos adversos , Saúde Global , Cooperação Internacional , Síndromes Neurotóxicas/prevenção & controle , Exposição Ocupacional/efeitos adversos , Saúde Ocupacional , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Poluição por Fumaça de Tabaco/efeitos adversos , Criança , Desenvolvimento Infantil/efeitos dos fármacos , Comportamento Cooperativo , Países em Desenvolvimento , Exposição Ambiental/efeitos adversos , Órgãos Governamentais , Humanos , Inteligência/efeitos dos fármacos , Relações Interinstitucionais , Síndromes Neurotóxicas/diagnóstico , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/psicologia , Medição de Risco , Fatores de Risco
18.
J Toxicol ; 2011: 983072, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21785592

RESUMO

Fish is a valuable source of nutrition, and many people would benefit from eating fish regularly. But some people eat a lot of fish, every day or several meals per week, and thus can run a significant risk of overexposure to methylmercury. Current advice regarding methylmercury from fish consumption is targeted to protect the developing brain and nervous system but adverse health effects are increasingly associated with adult chronic low-level methylmercury exposure. Manifestations of methylmercury poisoning are variable and may be difficult to detect unless one considers this specific diagnosis and does an appropriate test (blood or hair analysis). We provide information to physicians to recognize and prevent overexposure to methylmercury from fish and seafood consumption. Physicians are urged to ask patients if they eat fish: how often, how much, and what kinds. People who eat fish frequently (once a week or more often) and pregnant women are advised to choose low mercury fish.

19.
Toxicol Appl Pharmacol ; 208(1): 21-8, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16164958

RESUMO

Decades of research have demonstrated that exposure to methylmercury (MeHg), a ubiquitous environmental pollutant, can have both early and long-term neurobehavioral consequences in exposed offspring. The present study assessed visual functioning in adult macaque monkeys (Macaca fascicularis) exposed in utero to 0, 50, 70, or 90 microg/kg/day of MeHg hydroxide. Twenty-one full-term, normal birth weight offspring (9 controls, 12 exposed) were tested at approximately 11-14.5 years of age on a visual contrast sensitivity task. A forced-choice tracking procedure was utilized with spatial frequencies of 1, 4, 10, and 20 cycles per degree of visual angle. On each test session, a single spatial frequency was presented across five levels of contrast, each differing by 3 dB. Methylmercury-exposed monkeys exhibited reduced contrast sensitivity thresholds, particularly at the higher spatial frequencies. The degree of visual impairment was not related to MeHg body burden or clearance and almost half of the exposed animals were unimpaired. The results from this study demonstrate that chronic in utero MeHg exposure, at subclinical levels, is associated with permanent adverse effects on spatial vision in adult monkeys.


Assuntos
Compostos de Metilmercúrio/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Percepção Espacial/efeitos dos fármacos , Animais , Sensibilidades de Contraste/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Macaca fascicularis , Masculino , Exposição Materna/efeitos adversos , Compostos de Metilmercúrio/administração & dosagem , Compostos de Metilmercúrio/sangue , Gravidez , Testes de Toxicidade Crônica/métodos
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