Planning Ahead at the NTP
This month's NIEHS News (p. A400) describes five areas of ongoing NTP research that were endorsed at the last meeting of the program's Board of Scientific Counselors as priorities for future study. These areas reflect a growing presence of certain environmental health exposures in the daily lives of the American public.
Spotlight on Chromium
The Focus (p. A402) tells the story of hexavalent chromium (Cr[VI]), an industrial product that has been linked with lung and nasal cancers in humans. Additional health effects associated with various routes of exposure to Cr(VI) are the subject of an ongoing controversy, as scientists continue working to find out how much Cr(VI) is too much.
Pesticide Protection Pitfalls?
This month, the Spheres of Influence (p. A408) describes a March 2000 report by the General Accounting Office that investigates the risks faced by children in agriculture and the enforcement of pesticide protection standards for the estimated 2.5 million farmworkers employed in U.S. agriculture.
The New Age of Flow Cytometry
The Innovations (p. A412) takes a look at the work of Los Alamos scientists who built upon flow cytometry technology to create a device that uses laser beams to identify unknown molecules. The new flow cytometer shows great promise in fields such as genomics and disease transmission, offering the capability to study bacteria at the molecular level.
EMFs and Mammary Cancer in Rodents
In a Commentary, Anderson et al. (p. 797) examine differences in responses of the potential effects of weak magnetic fields on breast cancer in two rodent studies.
Research on Male Reproductive Health
Moline et al. (p. 803) review research on the effects of environmental contaminants on male reproductive health, particularly in the areas of testicular cancer, hypospadias, and cryptorchidism.
Air Toxics in Minnesota
Pratt et al. (p. 815) measured air toxics in Minnesota using monitoring and modeling between 1991 and 1998. Ten pollutants exceeded benchmark values at 
1 of 25 sites. Air pollutants were used to estimate cancer risk and noncancer hazards, providing
evidence that air toxics are a public health concern, especially in the Minneapolis-St. Paul metropolitan area.
Exposure to PCB 153 in Vitro and in Vivo
A rodent study by Hussain et al. (p. 827) showed that long-term potentiation in the brain, believed to be correlated with learning ability, was reduced after exposure to PCB 153. The authors suggest that this mechanism may explain the reduction of IQ in humans exposed to PCBs early in development. (Also see Science Selections, p. A416)
Indoor Cooking and Air Pollution in Kenya
Indoor air pollution from cooking cannot be studied with simple models that neglect the spatial distribution of pollution, intense emission episodes, and activity patterns within the home. Ezzati et al. (p. 833) report that health and intervention impact studies must include these factors when assessing risks for households in Kenya.
Subgroup Sensitivity to Airborne Particles
Zanobetti et al. (p. 841) found that the air pollution-associated increase in hospital admissions for cardiovascular diseases was almost doubled in subjects with concurrent respiratory infections. Individuals with asthma were at twice the risk of PM10-associated pneumonia admission, and those with heart failure were at twice the risk of PM10-induced chronic obstructive pulmonary disease admissions compared to individuals without these conditions.
Diabetes after Arsenic Exposure
Tseng et al. (p. 847) examined the incidence of non-insulin-dependent diabetes mellitus in Taiwanese villages and suggested that ingested inorganic arsenic was diabetogenic in humans.
PAH Exposure from Aircraft Exhaust
Potential exposure of individuals to exhaust pollutants was studied by Childers et al. (p. 853) at an Air National Guard base. A polycyclic aromatic hydrocarbon profile was dominated by naphthalene, alkyl-substituted naphthalenes, and other PAHs expected in the vapor phase, with total concentrations 10-25 times higher than those in ambient air. (Also see Science Selections, p. A417)
Quality of Bottled Water
Pip (p. 863) examined 40 brands of bottled water for total dissolved solids, chloride, sulfate, nitrate-nitrogen, cadmium, lead, copper, and radioactivity. Large variations in quality and some differences in toxic contaminates indicate the need for standardization of labeling and regulatory control.
Dietary Estrogens Interact with Estrogen Receptors
Plant estrogens are believed to play a role in the prevention of breast and prostate cancer. Nikov et al. (p. 867) evaluated the molecular mechanisms that might be operative, and showed that phytoestrogens can cause conformational changes in both human estrogen receptors that result in altered affinities of the complexes from the estrogen response elements of the Xenopus vit A2 gene and from the human pS2 gene. (Also see Science Selections, p. A416)
Cancer Mortality in Wheat Producing States
Schreinemachers (p. 873) examined the relationship between herbicides and cancer during 1980-1989. There were positive trends of increasing cancer mortality with increasing wheat acreage for a variety of cancers. Increased mortality was observed for cancer of the nose and eye in men and women, and brain and leukemia in boys and girls, suggesting an association between cancer mortality and wheat acreage in selected counties of Minnesota, North Dakota, South Dakota, and Montana.
Stillbirth and Public Water Chlorination
Water treatment with chlorine results in interactions with organic matter to produce by-products, including trihalomethanes. In a study in Nova Scotia, King et al. (p. 883) report that total trihalomethanes and specific trihalomethanes were each associated with increased stillbirth risk and with asphyxia-related deaths.
Air Pollution and Semen Quality
The relationship between male reproductive health and air pollution in the Czech Republic was reported by Selevan et al. (p. 887). Although there were no effects of air pollution on sperm counts, there were effects on sperm morphology and motility.
Phthalate Esters and Premature Breast Development
Puerto Rico has the highest incidence of thelarche, the growth of mammary tissue without other pubertal changes in girls younger than 8 years of age. Colón et al. (p. 895) observed high levels of phthalate esters and metabolites in affected girls, suggesting that endocrine disruption may have caused the changes.
Irritant-Induced Asthma and Carpet-Cleaning Chemicals: Exposure Modeling
A 42-year-old woman experienced an asthma attack, seizures, and unconsciousness immediately after having the carpet in her home cleaned and deodorized. Using exposure modeling, Lynch (p. 911) estimated that significant exposures to sodium tripolyphosphate and volatile organic compounds are possible during some carpet-cleaning activities.
Last Updated: September 20, 2000
