Faculty Bibliography

Exposure in prenatal life to methylmercury (MeHg) has become the topic of intense debate in the United States after the Environmental Protection Agency (EPA) announced a proposal in 2004 to reverse strict controls on emissions of mercury from coal-fired power plants that had been in effect for the preceding 15 years. This proposal failed to incorporate any consideration of the health impacts on children that would result from increased mercury emissions. We assessed the impact on children's health of industrial mercury emissions and found that between 316,588 and 637,233 babies are born with mercury-related losses of cognitive function ranging from 0.2 to 5.13 points. We calculated that decreased economic productivity resulting from diminished intelligence over a lifetime results in an aggregate economic cost in each annual birth cohort of $8.7 billion annually (range: $0.7-$13.9 billion, 2000 dollars). $1.3 billion (range: $51 million-$2.0 billion) of this cost is attributable to mercury emitted from American coal-fired power plants. Downward shifts in intellectual quotient (IQ) are also associated with 1566 (range: 115-2675) excess cases of mental retardation (MR defined as IQ < 70) annually. This number accounts for 3.2% (range: 0.2-5.4%) of MR cases in the United States. If the lifetime excess cost of a case of MR (excluding individual productivity losses) is $1,248,648 in 2000 dollars, then the cost of these excess cases of MR is $2.0 billion annually (range: $143 million-$3.3 billion). Preliminary data suggest that more stringent mercury policy options would prevent thousands of cases of MR and billions of dollars over the next 25 years

Chronic diseases of environmental origin are a significant and increasing public health problem among the children of New York State, yet few resources exist to address this growing burden. To assess New York State pediatricians self-perceived competency in dealing with common environmental exposures and diseases of environmental origin in children, we assessed their attitudes and beliefs about the role of the environment in children's health. A four-page survey was sent to 1,500 randomly selected members of the New York State American Academy of Pediatrics in February 2004. We obtained a 20.3% response rate after one follow-up mailing; respondents and nonrespondents did not differ in years of licensure or county of residence. Respondents agreed that the role of environment in children's health is significant (mean 4.44 +/- 0.72 on 1-5 Likert scale). They voiced high self-efficacy in dealing with lead exposure (mean 4.16-4.24 +/- 0.90-1.05), but their confidence in their skills for addressing pesticides, mercury and mold was much lower (means 2.51-3.21 +/- 0.90-1.23; p < 0.001). About 93.8% would send patients to a clinic 'where pediatricians could refer patients for clinical evaluation and treatment of their environmental health concerns.' These findings indicate that New York pediatricians agree that children are suffering preventable illnesses of environmental origin but feel ill-equipped to educate families about common exposures. Significant demand exists for specialized centers of excellence that can evaluate environmental health concerns, and for educational opportunities

BACKGROUND: Methylmercury (MeHg) is a developmental neurotoxicant; exposure results principally from consumption of seafood contaminated by mercury (Hg). In this analysis, the burden of mental retardation (MR) associated with methylmercury exposure in the 2000 U.S. birth cohort is estimated, and the portion of this burden attributable to mercury (Hg) emissions from coal-fired power plants is identified. METHODS: The aggregate loss in cognition associated with MeHg exposure in the 2000 U.S. birth cohort was estimated using two previously published dose-response models that relate increases in cord blood Hg concentrations with decrements in IQ. MeHg exposure was assumed not to be correlated with native cognitive ability. Previously published estimates were used to estimate economic costs of MR caused by MeHg. RESULTS: Downward shifts in IQ resulting from prenatal exposure to MeHg of anthropogenic origin are associated with 1,566 excess cases of MR annually (range: 376-14,293). This represents 3.2% of MR cases in the US (range: 0.8%-29.2%). The MR costs associated with decreases in IQ in these children amount to $2.0 billion/year (range: $0.5-17.9 billion). Hg from American power plants accounts for 231 of the excess MR cases/year (range: 28-2,109), or 0.5% (range: 0.06%-4.3%) of all MR. These cases cost $289 million (range: $35 million-2.6 billion). CONCLUSIONS: Toxic injury to the fetal brain caused by Hg emitted from coal-fired power plants exacts a significant human and economic toll on American children

Pediatricians can reduce exposures to environmental hazards but most have little training in environmental health. To assess whether Wisconsin pediatricians perceive a relative lack of self-efficacy for common environmental exposures and diseases of environmental origin, we assessed their attitudes and beliefs about the role of the environment in children's health. A 4-page survey was sent to the membership of the Wisconsin Chapter of the American Academy of Pediatrics. We obtained a 35.4% response rate after 1 follow-up mailing. Respondents agreed that the role of the environment in children's health is significant (mean 4.28 +/- .78 on 1-5 Likert scale). They expressed high confidence in dealing with lead exposure (means 4.22-4.27 +/- 1.01-1.09), but confidence in their skills for pesticide, mercury, and mold was much lower (means 2.49-3.09 +/- 1.06-1.26; P<.001). Of those surveyed, 88.6% would refer patients to a clinic 'where pediatricians could refer patients for clinical evaluation and treatment of their environmental health concerns.' These findings indicate that Wisconsin pediatricians agree that children are suffering preventable illnesses of environmental origin, but feel ill equipped to educate families about many common exposures. Significant demand exists for centers that can evaluate environmental health concerns, as well as for educational opportunities

Prospective, multi-year epidemiologic studies such as the Framingham Heart Study and the Nurses' Health Study have proven highly effective in identifying risk factors for chronic illness and in guiding disease prevention. Now, in order to identify environmental risk factors for chronic disease in children, the US Congress authorized a National Children's Study as part of the Children's Health Act of 2000. Enrollment of a nationally representative cohort of 100,000 children will begin in 2008, with follow-up to continue through age 21. Environmental assessment and examination of biomarkers collected at specified intervals during pregnancy and childhood will be a major component of the Study. Recruitment at 105 sites across the United States is planned, and will begin at 7 Vanguard Centers in 2008, including Waukesha County, Wis. The National Children's Study will provide information on preventable risk factors for such chronic diseases as asthma, certain birth defects, neurobehavioral syndromes, and obesity. In addition, the National Children's Study will provide training in pediatric environmental health for the next generation of researchers and practitioners

Parkinson disease (PD) and Alzheimer disease (AD), the two most common neurodegenerative disorders in American adults, are of purely genetic origin in a minority of cases and appear in most instances to arise through interactions among genetic and environmental factors. In this article we hypothesize that environmental exposures in early life may be of particular etiologic importance and review evidence for the early environmental origins of neurodegeneration. For PD the first recognized environmental cause, MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine), was identified in epidemiologic studies of drug abusers. Chemicals experimentally linked to PD include the insecticide rotenone and the herbicides paraquat and maneb; interaction has been observed between paraquat and maneb. In epidemiologic studies, manganese has been linked to parkinsonism. In dementia, lead is associated with increased risk in chronically exposed workers. Exposures of children in early life to lead, polychlorinated biphenyls, and methylmercury have been followed by persistent decrements in intelligence that may presage dementia. To discover new environmental causes of AD and PD, and to characterize relevant gene-environment interactions, we recommend that a large, prospective genetic and epidemiologic study be undertaken that will follow thousands of children from conception (or before) to old age. Additional approaches to etiologic discovery include establishing incidence registries for AD and PD, conducting targeted investigations in high-risk populations, and improving testing of the potential neurologic toxicity of chemicals

Methyl mercury is a developmental neurotoxicant. Exposure results principally from consumption by pregnant women of seafood contaminated by mercury from anthropogenic (70%) and natural (30%) sources. Throughout the 1990s, the U.S. Environmental Protection Agency (EPA) made steady progress in reducing mercury emissions from anthropogenic sources, especially from power plants, which account for 41% of anthropogenic emissions. However, the U.S. EPA recently proposed to slow this progress, citing high costs of pollution abatement. To put into perspective the costs of controlling emissions from American power plants, we have estimated the economic costs of methyl mercury toxicity attributable to mercury from these plants. We used an environmentally attributable fraction model and limited our analysis to the neurodevelopmental impacts--specifically loss of intelligence. Using national blood mercury prevalence data from the Centers for Disease Control and Prevention, we found that between 316,588 and 637,233 children each year have cord blood mercury levels > 5.8 microg/L, a level associated with loss of IQ. The resulting loss of intelligence causes diminished economic productivity that persists over the entire lifetime of these children. This lost productivity is the major cost of methyl mercury toxicity, and it amounts to $8.7 billion annually (range, $2.2-43.8 billion; all costs are in 2000 US$). Of this total, $1.3 billion (range, $0.1-6.5 billion) each year is attributable to mercury emissions from American power plants. This significant toll threatens the economic health and security of the United States and should be considered in the debate on mercury pollution controls

A growing body of research supports the role of outdoor air pollutants in acutely aggravating chronic diseases in children, and suggests that the pollutants may have a role in the development of these diseases. This article reviews the biologic basis of children's unique vulnerability to highly prevalent outdoor air pollutants, with a special focus on ozone, respirable particulate matter (PM 2.5 [<2.5 microm in diameter] and PM 10 [<10 microm in diameter]), lead, sulfur dioxide, carbon monoxide, and nitrogen oxides. We also summarize understanding regarding health effects and molecular mechanisms of action. Practitioners can significantly reduce morbidity in children and other vulnerable populations by advising families to minimize pollutant exposures to children with asthma, or at a broader level by educating policymakers about the need to act to reduce pollutant emissions. Management of children with asthma must expand beyond preventing exposures to agents that directly cause allergic reactions (and therefore can be diagnosed by means of skin tests) and must focus more attention on agents that cause a broad spectrum of nonspecific, generalized inflammation, such as air pollution