News
Found in the Translation
This month's NIEHS News (p. A150) describes the translational research being conducted under the Superfund Basic Research Program, which awards grants to university-based researchers looking for answers to human health questions in some of the nation's most toxic sites.
A Mine Is a Terrible Thing to Waste
Abandoned and orphaned mines may be forgotten by the companies that created them, but the environmental and human health problems they continue to pose are called to mind daily in countries worldwide. The Focus (p. A154) looks at what we know of how big the problems are and what's being done to limit the impact of these sites.
The Amazing Shrinking Superfund
Despite some spectacular environmental successes, Superfund has continually been plagued by naysayers and knotty negotiations. Now it faces its biggest challenge yet: a widening gap between how much funding it needs to operate and how much it's getting. The Spheres of Influence (p. A162) examines the dilemma of Superfund's shortfall and some possible solutions.
Research
Azole Fungicides Affect Steroidogenesis
Azole compounds are used as antifungals in agriculture and in pharmaceuticals for humans. Zarn et al. (p. 255) review sterol 14-demethylase and aromatase as targets of azole compounds and conclude that many azole compounds developed as inhibitors of fungal sterol 14-demethylase also inhibit mammalian sterol 14-demethylase and aromatase. Data on potencies of azole fungicides to human enzymes are needed for human health risk assessment.
Identifying Nuclear Waste Disposal Stakeholder Information Needs
The U.S. Department of Energy (DOE) is responsible for nuclear waste cleanup in the United States, and public stakeholders should be involved. The Consortium for Risk Evaluation with Stakeholder Participation organized focus groups, conducted exit surveys at DOE workshops, and developed visual information tools. Results indicate that public stakeholders are willing to participate but they need more effective technical information for meaningful participation (Drew et al., p. 263).
Responses of Baltic Clams to Contaminated Harbor Sediments
Sediments in Sydney Harbour, Nova Scotia, are contaminated with polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and heavy metals. Histopathologic and histochemical evaluations of the Baltic clam, Macoma balthica, exposed to 11 Sydney Harbour sediments show digestive gland tubular dilation or atrophy; tubular cell, germ cell, and ovarian cell necrosis; and increased acid phosphatase activity (Tay et al., p. 273).
EMF Do Not Induce HSP27 Responses in Human Keratinocytes
The linkage of 50-60 Hertz electromagnetic fields (EMF) with human cancer remains controversial, and in vitro human cell studies are inconclusive. Shi et al. (p. 281) investigated EMF-induced stress responses in human keratinocytes using the 27-kDa heat shock protein (HSP27) as a marker. The authors did not detect any stress responses in human keratinocytes exposed to power-line frequency EMF.
Threshold of TCE Affecting Fetal Rat Hearts
Trichloroethylene (TCE) is a common water supply contaminant, and rat studies demonstrate increases in cardiac malformations at high doses. Johnson et al. (p. 289) exposed rats to TCE (2.5 ppb, 250 ppb, 1.5 ppm, and 1,100 ppm) in drinking water throughout pregnancy and examined the fetuses. Exposure > 250 ppb resulted in a dose-dependent increase in cardiac abnormalities.
Determination of Arsenic Species in Urine
Milstein et al. (p. 293) used ion exchange chromatography coupled with inductively coupled plasma mass spectrometric detection to determine six arsenic species in human urine: arsenate (AsV), arsenite (AsIII), arsenocholine (AsC), arsenobetaine (AsB), monomethyl arsonic acid (MMA), and dimethyl arsinic acid (DMA). Baseline separation was achieved for all six species, and performance was evaluated for linearity, precision, accuracy, detection limits, and precision.
Chlorpyrifos and Developmental Neurotoxicity
Developmental neurotoxicity of chlorpyrifos is thought to involve both neurons and glia to produce prolonged vulnerability. To characterize the cell types and brain regions involved, Garcia et al. (p. 297) administered chlorpyrifos to developing rats and examined neuroprotein markers for oligodendrocytes, neuronal cell bodies, and developing axons. Results indicate a shift in the populations of neural cells targeted by chlorpyrifos dependent upon the period of exposure.
Fenitrothion Toxicity in Humans
Fenitrothion is a widely used organophosphate insecticide. Meaklim et al. (p. 305) administered daily doses of 0.18 and 0.36 mg/kg/day fenitrothion for 4 days in 12 human volunteers. Blood and urine samples were collected for analysis of metabolites, plasma and red blood cell cholinesterase activities, biochemistry, and hematology. The authors found no significant change in measured blood parameters at either dosage level.
Bisphenol A Metabolism in Pregnant Mice
The metabolic fate of a low-dose bisphenol A was investigated in pregnant CD1 mice using a tritium-labeled molecule (Zalko et al., p. 309). The metabolic routes were far more complex than previously thought. Although the estrogenicity of untested metabolites cannot be ruled out, the data suggest the parental compound is responsible for estrogenic effects observed in fetuses exposed during gestation.
GIS Characterization of Herbicide Usage in Vietnam
Limited epidemiologic and environmental research has been conducted on distribution and health effects of herbicide contamination in Vietnam between 1961 and 1971. A geographic information system (GIS) has been developed to generate a quantitative exposure score that accounts for quantity of herbicide sprayed, distance, and environmental decay (Stellman et al., p. 321). The GIS provides for estimation of herbicide exposure in large epidemiologic studies. (Also see Science Selections, p. A167)
Estrogenic Activity of Styrene Oligomers after Metabolic Activation
Styrene oligomers are incorporated into polystyrene food containers. Kitamura et al. (p. 329) examined the estrogenic activity of several styrene oligomers after metabolic activation by rat liver microsomes using a yeast estrogen screening assay and an estrogen-responsive human breast cancer cell line (MCF-7). A 4-hydroxylated metabolite of trans-1,2-diphenylcyclobutane exhibited significant estrogenic activity.
Environmental Medicine
ALAD Polymorphism and Low-Level Lead Exposure in Aging Men
Wu et al. (p. 335) investigated whether a -aminolevulinic acid dehydratase (ALAD) exon 4 polymorphism modifies association of blood or bone lead with uricemia and renal function in middle-aged and elderly men. The relationships of serum uric acid, serum creatinine, and estimated creatinine clearance to lead level were stratified by genotype. The ALAD genotype may modify the effect of lead on the renal excretion of uric acid and overall renal function.
Long-Term Follow-Up of the Three Mile Island Area, 1979-1998
Talbott et al. (p. 341) report on the 1979-1998 cohort (n = 32,125) mortality study in the Three Mile Island (TMI) accident area. They used standardized mortality ratios and relative risk regression to compare the cohort and the local population. Although several elevations persist and certain response relationships cannot be definitively excluded, there is no consistent evidence that the accident had a significant impact on the mortality of TMI residents. (Also see Science Selections, p. A166)
Determinants of Organochlorine Serum Concentrations in Swedish Women
Glynn et al. (p. 349) studied associations between lifestyle/medical factors and lipid-adjusted serum concentrations of seven PCB congeners and five chlorinated pesticides/metabolites among 205 Swedish women (age 54-75 years). Serum concentrations were significantly associated with age, body mass index, body weight change, diabetes mellitus, consumption of fatty fish, and place of residence. The findings suggest that lifestyle/medical factors may confound results in epidemiologic studies when they are related to both serum concentrations and disease.
Children's Health
PCB Exposure and Neuropsychological Function in Children
Advances in polychlorinated biphenyl (PCB) analytical methods have resulted in widespread congener-specific analyses, revealing that environmental PCB residues do not closely resemble commercial PCB mixtures (Schantz et al., p. 357). The different congener classes have different patterns of toxicity. Evidence for neurodevelopment effects is growing, but the nervous system potency of many congeners present in human tissues is unknown.
Organic Produce and Pesticide Exposure in Children
Curl et al. (p. 377) assessed organophosphorus (OP) pesticide exposure from diet among Seattle preschool children classified as consuming either organic or conventional diets based on analysis of diary data. The dose estimates suggest that consumption of organic fruits, vegetables, and juice can reduce children's exposure levels from above to below the U.S. Environmental Protection Agency's current guidelines. (Also see Science Selections, p. A166)
Association of Lung Function with Declining Ambient Air Pollution
Air quality in East Germany has been improving since reunification. Frye et al. (p. 383) conducted three consecutive cross-sectional surveys of 11- to 14-year-old schoolchildren from three communities in East Germany for 1992-1993, 1995-1996, and 1998-1999. Results indicate that a reduction of air pollution in a relatively short period may significantly improve children's lung function.
Correction
The February Science Selections article "Size in the City: New York Pollution May Lower Birth Weight" [EHP 111:A110 (2003)] incorrectly states that the Polish population was exposed to 46% higher concentrations of PAHs than the present New York City cohort. In fact, the Polish population was exposed to at least 10- to 20-fold higher concentrations of PAHs than the present New York City cohort. EHP regrets the error.
Last Updated: February 29, 2002