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We performed two studies to investigate environmental factors in relation to neurological development in infants. The first, a field study, examined the elementary school performance of 929 children who were born from mothers exposed to the atomic bombing of Hiroshima, Japan, August 6, 1945. The most severe mental retardation was observed in the group exposed between 8 and 15 weeks following fertilization, and the second most severely damaged group was exposed between 16 and 25 weeks. The second, a clinical investigation, examined infants in the perinatal center who survived intrauterine growth retardation (IUGR). Those who survived with abnormal neurological development had a mean growth arrest corresponding to a uterine height of 27 weeks of gestation. This was at an earlier stage than those who survived with normal neurological development and had a mean growth arrest corresponding to 29-30 weeks of gestation. A smaller head circumference at birth was closely correlated with abnormal neurological sequelae. These results indicate that the brain development of the fetuses may have been affected by neurotoxic events similar to ionizing radiation. We emphasize the importance of avoiding neurotoxic stress to pregnant women when the fetus is in the critical period of neuronal development, before 27 weeks of gestational age.

Background: Above-ground and underground nuclear weapon detonation at the Nevada Test Site (1951-1992) has resulted in radioiodine exposure for nearby populations. Although the long-term effect of environmental radioiodine exposure on thyroid disease has been well studied, little is known regarding the effect of childhood radioiodine exposure on subsequent fertility. Objectives: We investigated early childhood thyroid radiation exposure from nuclear testing fallout (supplied predominantly by radioactive isotopes of iodine) and self-reported lifetime incidence of male or female infertility or sterility. Methods: Participants were members of the 1965 Intermountain Fallout Cohort, schoolchildren at the time of exposure who were reexamined during two subsequent study phases to collect dietary and reproductive histories. Thyroid radiation exposure was calculated via an updated dosimetry model. We used multivariable logistic regression with robust sandwich estimators to estimate odds ratios for infertility, adjusted for potential confounders and (in separate models) for a medically confirmed history of thyroid disease. Results: Of 1,389 participants with dosimetry and known fertility history, 274 were classified as infertile, including 30 classified as sterile. Childhood thyroid radiation dose was possibly associated with infertility [adjusted odds ratio (AOR) = 1.17; 95% CI: 0.82, 1.67 and AOR = 1.35; 95% CI: 0.96, 1.90 for the middle and upper tertiles vs. the first tertile of exposure, respectively]. The odds ratios were attenuated (AOR = 1.08; 95% CI: 0.75, 1.55 and AOR = 1.29; 95% CI: 0.91, 1.83 for the middle and upper tertiles, respectively) after adjusting for thyroid disease. There was no association of childhood radiation dose and sterility. Conclusion: Our findings suggest that childhood radioiodine exposure from nuclear testing may be related to subsequent adult infertility. Further research is required to confirm this. [ABSTRACT FROM AUTHOR]

Background: Although high doses of ionizing radiation have long been linked to circulatory disease, evidence for an association at lower exposures remains controversial. However, recent analyses suggest excess relative risks at occupational exposure levels. Objectives: We performed a systematic review and meta-analysis to summarize information on circulatory disease risks associated with moderate- and low-level whole-body ionizing radiation exposures. Methods: We conducted PubMed/ISI Thomson searches of peer-reviewed papers published since 1990 using the terms "radiation" AND "heart" AND "disease," OR "radiation" AND "stroke," OR "radiation" AND "circulatory" AND "disease." Radiation exposures had to be whole-body, with a cumulative mean dose of < 0.5 Sv, or at a low dose rate (< 10 mSv/day). We estimated population risks of circulatory disease from low-level radiation exposure using excess relative risk estimates from this meta-analysis and current mortality rates for nine major developed countries. Results: Estimated excess population risks for all circulatory diseases combined ranged from 2.5%/Sv [95% confidence interval (CI): 0.8, 4.2] for France to 8.5%/Sv (95% CI: 4.0, 13.0) for Russia. Conclusions: Our review supports an association between circulatory disease mortality and low and moderate doses of ionizing radiation. Our analysis was limited by heterogeneity among studies (particularly for noncardiac end points), the possibility of uncontrolled confounding in some occupational groups by lifestyle factors, and higher dose groups (> 0.5 Sv) generally driving the observed trends. If confirmed, our findings suggest that overall radiation-related mortality is about twice that currently estimated based on estimates for cancer end points alone (which range from 4.2% to 5.6%/Sv for these populations). [ABSTRACT FROM AUTHOR]

BACKGROUND: The number of newborn boys was higher than that of girls in the Czech Republic each month from 1950 to 2005. The only exception was November 1986, when the number of newborn boys was significantly reduced. This has been explained by a selective negative impact of the Chernobyl accident in April 1986 on male fetuses during the third month of their prenatal development. OBJECTIVES: The first and most radioactive cloud passed over the Czech Republic during 30 April-1 May 1986. Concurrent rainfall multiplied the radioactivity by up to > 10,000-fold in specific regions. We verified a hypothesis that the decrease in the male birth fraction in November 1986 correlated with the level of radiation in eight Czech regions after the Chernobyl disaster. RESULTS: We found a relationship between the level of radiation and the decrease in the number of newborn boys. The number of newborn boys was decreased in the six eastern regions where the radiation was strongly increased due to rain that accompanied the radioactive cloud. In contrast, the number of newborn boys was not reduced in the two western regions where the radioactivity was markedly lower. CONCLUSIONS: A negative impact of radiation on the prenatal population was manifested as a selective loss of newborn boys in November 1986. This loss correlated with level of radioactivity. The 131I probably played the most important role because of its up-take during primary saturation of fetal thyroid by iodine, which accompanies the onset of the gland function in 3-month-old fetuses. [ABSTRACT FROM AUTHOR]

BACKGROUND: There is growing evidence for the role of oxidative damage in chronic diseases. Although ozone (O3) is an oxidant pollutant to which many people are exposed, few studies have examined whether O3 induces oxidative stress in humans. OBJECTIVES: This study was designed to assess the effect of short- and long-term O3 exposures on biomarkers of oxidative stress in healthy individuals. METHODS: Biomarkers of lipid peroxidation, 8-isoprostane (8-iso-PGF), and antioxidant capacity ferric reducing ability of plasma (FRAP) were analyzed in two groups of healthy college students with broad ranges of ambient O3 exposure during their lifetimes and previous summer recess either in Los Angeles (LA, n = 59) or the San Francisco Bay Area (SF, n = 61). RESULTS: Estimated 2-week, 1-month, and lifetime O3 exposures were significantly correlated with elevated 8-iso-PGF. Elevated summertime exposures resulted in the LA group having higher levels of 8-iso-PGF than the SF group (p = 0.02). Within each location, males and females had similar 8-iso-PGF. No regional difference in FRAP was observed, with significantly higher FRAP in males in both groups (SF: p = 0.002; LA: p = 0.004). An exposure chamber substudy (n = 15) also showed a significant increase in 8-iso-PGF as well as an inhibition of FRAP immediately after a 4-hr exposure to 200 ppb O3, with near normalization by 18 hr in both biomarkers. CONCLUSIONS: Long-term exposure to O3 is associated with elevated 8-iso-PGF, which suggests that 8-iso-PGF is a good biomarker of oxidative damage related to air pollution. [ABSTRACT FROM AUTHOR]

Although overall incidence is rare, leukemia is the most common type of childhood cancer. It accounts for 30% of all cancers diagnosed in children younger than 15 years. Within this population, acute lymphocytic leukemia (ALL) occurs approximately five times more frequently than acute myelogenous leukemia (AML) and accounts for approximately 78% of all childhood leukemia diagnoses. Epidemiologic studies of acute leukemias in children have examined possible risk factors, including genetic, infectious, and environmental, in an attempt to determine etiology. Only one environmental risk factor (ionizing radiation) has been significantly linked to ALL or AML. Most environmental risk factors have been found to be weakly and inconsistently associated with either form of acute childhood leukemia. Our review focuses on the demographics of childhood leukemia and the risk factors that have been associated with the development of childhood ALL or AML. The environmental risk factors discussed include ionizing radiation, non-ionizing radiation, hydrocarbons, pesticides, alcohol use, cigarette smoking, and illicit drug use. Knowledge of these particular risk factors can be used to support measures to reduce potentially harmful exposures and decrease the risk of disease. We also review genetic and infectious risk factors and other variables, including maternal reproductive history and birth characteristics. [ABSTRACT FROM AUTHOR]

BACKGROUND: The Chernobyl accident in 1986 caused widespread radioactive contamination and enormous concern. Twenty years later, the World Health Organization and the International Atomic Energy Authority issued a generally reassuring statement about the consequences. Accurate assessment of the consequences is important to the current debate on nuclear power. OBJECTIVES: Our objectives in this study were to evaluate the health impact of the Chernobyl accident, assess the international response to the accident, and consider how to improve responses to future accidents. DISCUSSION: So far, radiation to the thyroid from radioisotopes of iodine has caused several thousand cases of thyroid cancer but very few deaths; exposed children were most susceptible. The focus on thyroid cancer has diverted attention from possible nonthyroid effects, such as mini-satellite instability, which is potentially important. The international response to the accident was inadequate and uncoordinated, and has been unjustifiably reassuring. Accurate assessment of Chernobyl's future health effects is not currently possible in the light of dose uncertainties, current debates over radiation actions, and the lessons from the late consequences of atomic bomb exposure. CONCLUSIONS: Because of the uncertainties over the dose from and the consequences of the Chernobyl accident, it is essential that investigations of its effects should be broadened and supported for the long term. Because of the problems with the international response to Chernobyl, the United Nations should initiate an independent review of the actions and assignments of the agencies concerned, with recommendations for dealing with future international-scale accidents. These should involve independent scientists and ensure cooperation rather than rivalry. [ABSTRACT FROM AUTHOR]

Arsenic in drinking water is an established cause of lung cancer, and preliminary evidence suggests that ingested arsenic may also cause nonmalignant lung disease. Antofagasta is the second largest city in Chile and had a distinct period of very high arsenic exposure that began in 1958 and lasted until 1971, when an arsenic removal plant was installed. This unique exposure scenario provides a rare opportunity to investigate the long-term mortality impact of early-life arsenic exposure. In this study, we compared mortality rates in Antofagasta in the period 1989–2000 with those of the rest of Chile, focusing on subjects who were born during or just before the peak exposure period and who were 30–49 years of age at the time of death. For the birth cohort born just before the high-exposure period (1950–1957) and exposed in early childhood, the standardized mortality ratio (SMR) for lung cancer was 7.0 [95% confidence interval (CI), 5.4–8.9; p < 0.001] and the SMR for bronchiectasis was 12.4 (95% CI, 3.3–31.7; p < 0.001). For those born during the high-exposure period (1958–1970) with probable exposure in utero and early childhood, the corresponding SMRs were 6.1 (95% CI, 3.5–9.9; p < 0.001) for lung cancer and 46.2 (95% CI, 21.1–87.7; p < 0.001) for bronchiectasis. These findings suggest that exposure to arsenic in drinking water during early childhood or in utero has pronounced pulmonary effects, greatly increasing subsequent mortality in young adults from both malignant and nonmalignant lung disease. [ABSTRACT FROM AUTHOR]

Focuses on various perspectives concerning environmental health. Carcinogenicity of ethylene bisdithiocarbamate fungicides; Concerns about using cancer risks derived from the Life Span Study cohort of Japanese atomic bomb survivor data in radiation worker compensation plans.

Rates of developmental and respiratory diseases are disproportionately high in underserved, minority populations such as those in New York City's Washington Heights, Harlem, and the South Bronx. Blacks and Latinos in these neighborhoods represent high risk groups for asthma, adverse birth outcomes, impaired development, and some types of cancer. The Columbia Center for Children's Environmental Health in Washington Heights uses molecular epidemiologic methods to study the health effects of urban indoor and outdoor air pollutants on children, prenatally and postnatally, in a cohort of over 500 African-American and Dominican (originally from the Dominican Republic) mothers and newborns. Extensive data are collected to determine exposures to paniculate matter < 2.5 µm in aerodynamic diameter (PM[sub2.5]), polycyclic aromatic hydrocarbons (PAHs), diesel exhaust paniculate (DEP), nitrogen oxide, nonpersistent pesticides, home allergens (dust mite, mouse, cockroach), environmental tobacco smoke (ETS), and lead and other metals. Biomarkers, air sampling, and clinical assessments are used to study the effects of these exposures on children's increased risk for allergic sensitization, asthma and other respiratory disorders, impairment of neurocognitive and behavioral development, and potential cancer risk. The center conducts its research and community education in collaboration with 10 community-based health and environmental advocacy organizations. This unique academic-community partnership helps to guide the center's research so that it is most relevant to the context of the low-income, minority neighborhoods in which the cohort resides, and information is delivered back to these communities in meaningful ways. In turn, communities become better equipped to relay environmental health concerns to policy makers. In this paper we describe the center's research and its academic-community partnership and present some preliminary findings. Key words: asthma, cancer... [ABSTRACT FROM AUTHOR]

Provides developments on environmental health research. Evaluation of the carcinogenicity of trichloroethylene using meta-analysis type approach; Presentation of the effects of errors in particulate matter exposure assessment in time-series mortality analyses.

Presents a statistical analysis of time trends of perinatal mortality in Germany. Possible increase perinatal mortality in 1987 due to effect of the Chernobyl accident; Application of regression techniques to determine the impact of statistical models on results; Comparison of findings with radiobiologic data.

Expounds on the role of epidemiology in the detection of harmful effects of radiation. Inaccuracies of data on acute injuries of atomic bomb survivors taken from life span cohort studies; Preferability of using linear extrapolation of the high dose effects observed in atomic bomb survivors.

Presents a response by Fernanda Cavieres et al to a letter to the editor about her article on the developmental effects of herbicides in mice.

A letter to the editor is presented in response to the article "Methylmercury and the Developing Brain,” by Griffiths and colleagues which appeared in a previous 2007 issue.

A letter to the editor is presented in response to the article "Risk Factors for Acute Leukemia in Children,” by Belson and colleagues which appeared in a previous 2007 issue.

Presents corrections to articles published in 2003 issues of 'Environmental Health Perspectives.' Omission of a negative sign in an equation in an article by Wilhelm and Ritz; Correction to the article titled 'Atrazine-Induced Hermaphroditism at 0.1 ppb in American Leopard Frogs: Laboratory and Field Evidence.'

BACKGROUND: Above-ground and underground nuclear weapon detonation at the Nevada Test Site (1951-1992) has resulted in radioiodine exposure for nearby populations. Although the long-term effect of environmental radioiodine exposure on [...]

OBJECTIVE: We conducted a review of the history and performance of developmental neurotoxicity (DNT) testing in support or the finalization and implementation of Organisation of Economic Co-operation and Development (OECD) [...]

BACKGROUND: There is growing evidence for the role of oxidative damage in chronic diseases. Although ozone ([O.sub.3]) is an oxidant pollutant to which many people are exposed, few studies have examined whether [O.sub.3] induces oxidative stress in humans. OBJECTIVES: This study was designed to assess the effect of short- and long-term [O.sub.3] exposures on biomarkers of oxidative stress in healthy individuals. METHODS: Biomarkers of lipid peroxidation, 8-isoprostane (8-iso-PGF), and antioxidant capacity ferric reducing ability of plasma (FRAP) were analyzed in two groups of healthy college students with broad ranges of ambient [O.sub.3] exposure during their lifetimes and previous summer recess either in Los Angeles (LA, n = 59) or the San Francisco Bay Area (SF, n = 61). RESULTS: Estimated 2-week, 1-month, and lifetime [O.sub.3] exposures were significantly correlated with elevated 8-iso-PGF. Elevated summertime exposures resulted in the LA group having higher levels of 8-iso-PGF than the SF group (p = 0.02). Within each location, males and females had similar 8-iso-PGF. No regional difference in FRAP was observed, with significantly higher FRAP in males in both groups (SF: p = 0.002; LA: p = 0.004). An exposure chamber substudy (n = 15) also showed a significant increase in 8-iso-PGF as well as an inhibition of FRAP immediately after a 4-hr exposure to 200ppb [O.sub.3], with near normalization by 18hr in both biomarkers. CONCLUSIONS: Long-term exposure to [O.sub.3] is associated with elevated 8-iso-PGF, which suggests that 8-iso-PGF is a good biomarker of oxidative damage related to air pollution. KEY WORDS: antioxidant capacity, FRAP, isoprostane, lifetime exposure, lipid peroxidation, plasma, oxidative injury, ozone. Environ Health Perspect 115:1732-1737 (2007). doi:10.1289/ehp.10294 available via http://dx.doi.org/ [Online 11 September 2007], Oxidant generation is part of the normal metabolism of many cell types and is critical for homeostasis. Humans have evolved an antioxidant system to protect against oxidative stress--a state of [...]

Hormesis (defined operationally as low-dose stimulation, high-dose inhibition) is often used to promote the notion that while high-level exposures to toxic chemicals could be detrimental to human health, low-level exposures [...]

During the first century of the development of the mouse as a model organism for biological research, mouse models were inbred with the goal of achieving genetic homogeneity within strains [...]

I read with interest the letter of Wing and Richardson (2002), which raised concerns about using cancer risks derived from the Life Span Study (LSS) cohort of Japanese atomic-bomb survivor [...]

We appreciate the interest of Wing and Richardson in our recent follow-up of mortality in the Three Mile Island (TMI) cohort (1). We concur with the suggestion that our data [...]

Wakeford (2003) and Little (2003) wrote in response to our comments about the use of A-bomb survivor studies as a basis for U.S. nuclear worker compensation decisions (Wing and Richardson [...]