Magnetic Personalities Gather
The NIEHS recently presented the second in a series of symposia designed to debate and discuss the state of the science in the controversial area of extremely low frequency electric and magnetic fields. The
NIEHS News
article on p. A176 provides an overview of the issues covered at the symposium.
Building a Better Mouse Model
Recent research findings on three different transgenic mouse models--gleaned from studies conducted in the United States and Japan--were reviewed and discussed at a February meeting at the NIEHS. These findings, discussed in the
NIEHS News
article on p. A176, may lead to improved testing for drug and chemical carcinogenicity.
Spreading the Word on Toxic Exposures
The International Programme on Chemical Safety, described in the
Spheres of Influence
article (p. A178), was created in response to the growing need for public information on toxic chemical exposures. Scientists and health professionals from around the world are working to help the program reach its goal of enabling United Nations member states to develop their own scientifically sound chemical safety measures.
A New Weapon Against Chemical Warfare
Scientists in Pittsburgh, Pennsylvania, have developed a new product that may protect against the adverse health effects of some chemical nerve agents and pesticides. The
Innovations
article (p. A182) looks at the technology behind enzyme-laden sponges that can be used to effectively wipe harmful chemicals from skin and clothing.
Cadmium in Human Kidneys
Cadmium concentrations in 171 kidney cortex biopsies from Sweden indicated reductions between the 1970s and the 1990s (Friis et al., p. 175), possibly because of changes in dietary habits and/or reductions in contamination from industries.
Liver Tumors in Whitefish from Canada
Liver lesions were examined by
Mikaelian et al.
(p. 179) in lake whitefish from the St. Lawrence River. The prevalence of liver neoplasia was 4.9%, all in fish
7 years old, and is the first report on a series of liver tumors in a wild salmonid species.
DDE and Sexual Differentiation in Marine Turtles
The potential effects of the pesticide metabolite DDE on sexual differentiation of green sea turtles in Australia was investigated by
Podreka et al.
(p. 185). Data indicated that exposure of turtle eggs in the wild to DDE concentrations less than 543 ng/g would not affect hatching success, survival rate, or normal differentiation of reproductive organs.
Lung Cancer and Proximity to Industry
The effects of long-term exposure to industrial air pollution on cancer mortality were investigated by
Pless-Mulloli et al.
(p. 189). There was an association between elevated lung cancer mortality and proximity to industry in women under 75 years of age that could not be attributed to smoking, occupation, socioeconomic factors, or artefact, suggesting that industrial air pollution was a contributing factor to the observations.
Chromosome Damage from Triazine Mixtures
Taets et al.
(p. 197) investigated the clastogenic potential of herbicides to Chinese hamster ovary cells to determine the potential effects of low levels of pesticides in drinking water supplies. Cells were exposed to three different herbicides and all combinations for 48 hours at maximum contamination levels allowed, and at the highest levels found for these contaminants in Illinois water samples. Atrazine and simazine caused different types of genetic toxicity, but no synergy was observed.
Modulation of Estradiol Metabolism in MCF-7 Cells
The effects of several pesticides, mammary carcinogens, and antiestrogens on the metabolism of estradiol in MCF-7 cells indicated variable responses that were dependent upon the class of compound administered
(McDougal and Safe, p. 203). A radiometric assay was used to evaluate responses to DMBA, benzo(a)pyrene, kepone, atrazine, DDE, DDT, hexachlorocyclohexane, indole-3-carbinol, tamoxifen, hydroxytamoxifen, retinoic acids, dioxin, and the antiestrogen ICI 182,780.
p53
Mutations in Human Cancer
Mutation databases for the
p53
tumor suppressor gene were examined by
Lutz et al.
(p. 207) because mutations of this gene occur in about 50% of human cancers. The base pair-specific, quantitative, organ-to-organ comparison of the complete
p53
mutation spectra enabled formulation of new hypotheses for insights into carcinogenesis.
Blood Lead and
-ALAD Genotypes
Individual susceptibility to lead poisoning was examined by
Alexander et al.
(p. 213) by measuring blood lead, zinc protoporphyrin, urinary coproporphyrin, and ALAD genotype in employees from a lead-zinc smelter. The ALAD genetic polymorphism appeared to modify the association between blood lead and zinc protoporphyrin and, to a lesser extent, with urinary coproporphyrin.
Environmental Equity at Oregon Hazardous Sites
Neumann et al.
(p. 217) ranked chemicals on the EPA's Toxic Release Inventory, an inventory of chemicals released into the environment or transferred to sewage treatment plants or other sites for disposal and recycling. Based on oral toxicity or total mass, the principle chemicals identified were glycol ethers, nickel, trichloroethylene, chloroform, manganese, methanol, ammonia, acetone, and toluene. Using hazard screening, demographic analysis, and a geographic information system, they determined that the facilities for handling the toxic chemicals were disproportionately located in racial and ethnic neighborhoods.
Last Update: March 25, 1998