Endocrine Review Revealed
The National Toxicology Program's Report of the Endocrine Disrupters Low-Dose Peer Review, released in May 2001, sums up the evaluation of an independent panel of experts on the evidence for low-dose effects and dose-response relationships for endocrine disruptors. The NIEHS News (p. A420) explains the panel's findings.
Drive-By Exposures
Is congested traffic driving you mad? It might also be making you sick: driving in tightly packed traffic can raise pollutant levels inside cars to 2-10 times the levels by the side of the road. The Focus (p. A422) looks at some of the potential exposures drivers face and what can be done to alleviate them.
Candy Apple Technology
Lightweight, durable, easy and inexpensive to manufacture, and using few environmentally
unfriendly chemicals, polypropylene has all the earmarks of an excellent car
molding material, all the earmarks but one: it can't be painted. The Innovations
(p. A430) looks at a new technology known as SICOR, which allows manufacturers
to treat polypropylene to create a paintable, bondable surface, making this
material a more feasible option for greener automobiles.
The Precautionary Principle and Environmental Science
Kriebel et al. (p. 871) examined the implications of the precautionary principle for environmental scientists, who study highly complex, poorly understood systems while facing conflicts in how to balance economic growth with environmental protection. The authors suggest that environmental scientists should be aware of how their work may be used to set policy and of their social responsibility when conducting research.
Risks of Ionizing Radiation
De Brouwer and Lagasse (p. 877) review an important issue--the controversies surrounding the interpretation of studies on health effects following exposures to low levels of ionizing radiation. The authors propose an alternative epidemiologic paradigm for defining causation that would suggest fruitful directions for further studies and allow reconciliation of apparently contradictory conclusions by different investigators.
Application of DNA Microarrays
The application of microarray technology for fundamental research was reviewed by Lobenhofer et al. (p. 881). This process uses microarrays (or DNA chips) to evaluate the gene expression profiles of biological samples. The review focuses not on technology, but on the application of microarrays as a research tool and on the future challenges in this field.
Can Allium Vegetables and Organosulfur Compounds Help Prevent Cancer?
Bianchini and Vainio (p. 893) review the beneficial effects of Allium vegetables (garlic, onions, leeks, and chives) against several diseases. The protective effects against cancer appear to be related to the presence of organosulfur compounds, mainly allyl derivatives, which inhibit carcinogenesis in the forestomach, esophagus, colon, mammary gland, and lung of experimental animals. Organosulfur compounds detoxify carcinogens, inhibit the formation of DNA adducts, and exhibit antiproliferative activity, but clinical trials are required to define effective doses that are not toxic in humans.
Brominated Flame Retardants as Developmental Neurotoxicants
Two polybrominated diphenyl ether (PBDE) congeners (both common in environmental and human samples) and a frequently used brominated flame retardant were studied for developmental neurotoxic effects by Eriksson et al. (p. 903). The authors orally administered the compounds to 10-day-old male mice. Neonatal exposure to PBDE 99 and PBDE 47 caused dose-related permanent aberrations in spontaneous behavior. Neonatal exposure to PBDE 99 also affected learning and memory functions in adult animals. These developmental defects have previously been detected in connection with PCBs. (Also see Science Selections, p. A434)
Chlorpyrifos Neurotoxicity in Vitro
Qiao et al. (p. 909) examined the effects of chlorpyrifos and its major metabolites in two neuronal cell lines. Chlorpyrifos inhibited DNA synthesis in both lines but had a greater effect on gliotypic cells. Chlorpyrifos oxon, the active metabolite that inhibits cholinesterase, also decreased DNA synthesis in PC12 and C6 cells, with a preferential effect on C6 cells. The authors suggest that chlorpyrifos has immediate, direct effects on neural cell replication, preferentially for gliotypic cells.
Asbestos Exposure and Lung Cancer
Magnani et al. (p. 915) evaluated environmental and domestic asbestos exposure in an Italian city with a large asbestos cement factory. Diagnoses of pleural malignant mesothelioma (102 cases) were confirmed by a panel of five pathologists. Living in Casale was associated with a high risk of cancer that decreased with increasing distance of the residence from the factory.
Respiratory Toxicity of 1,3-Butadiene
In their investigation of physiologic factors in the respiratory uptake of 1,3-butadiene, Lin et al. (p. 921) found that the blood:air partition coefficient and alveolar ventilation were most significant in determining respiratory uptake. The authors suggest that, in future epidemiologic research, interindividual variation in human physiologic factors that affect the exposure-internal dose relationship should be considered while exploring exposure-disease associations.
Kinetics of TCPMe and TCPMOH in the Japanese
Minh et al. (p. 927) examined adipose tissue, liver, and bile from humans in Japan to determine the contamination status, specific accumulation, and elimination of two newly identified environmental contaminants, tris(4-chlorophenyl)methane (TCPMe) and tris(4-chlorophenyl)methanol (TCPMOH). The authors observed age-dependent accumulation of TCPMe, TCPMOH, and other organochlorines, and suggest that the relationship between excretion rate and octanol-water partition coefficient may be used to predict the biliary excretion potential of some other lipophilic organochlorines.
Formation Airway Irritants
Wilkins et al. (p. 937) used a mouse bioassay to evaluate the airway irritation caused by isoprene, isoprene/ozone, and isoprene/ozone/nitrogen dioxide mixtures and to calculate sensory irritation, bronchial constriction, and pulmonary irritation. The upper airway irritation could not be explained by the concentrations of residual reactants and reaction products that were identified. This suggests that additional irritants were formed and that oxidation reactions of common unsaturated compounds may be relevant for indoor air quality.
Toxicity of Diethylnitrosamine
In an investigation of the effects of diethylnitrosamine (DEN) in rats, Liao et al. (p. 943) determined that toxic changes suggest that DEN treatment may cause pituitary damage, disturb serum hormone levels, and induce long-lasting reduction of sexual dimorphism in certain liver functions.
Gastrointestinal Effects of Copper in Drinking Water
Pizarro et al. (p. 949) conducted studies in Chilean women to determine whether total copper or soluble copper concentration was associated with gastrointestinal signs and symptoms. The authors found no differences in the incidences of abdominal pain, nausea, vomiting, and diarrhea, regardless of the ratio of copper sulfate to copper oxide, implying that similar levels of ionic copper were absorbed.
Health Hazards of High-Production Volume Chemicals
Cunningham and Rosenkranz (p. 953) used structure-activity relationship modeling to estimate the number of toxic chemicals among the high-production volume group. They estimated that the subset of high-production volume chemicals contained a significantly lower proportion of toxicants than expected as compared to a reference set of 10,000 chemicals. (Also see Science Selections, p. A435)
PCBs and Methylmercury Exposure in Pregnant Inuits
Body burdens of contaminants in pregnant Inuit women from three communities were evaluated by Muckle et al. (p. 957). Consumption of fish and seal meat was associated with increased hair mercury concentrations. Despite widespread knowledge of contaminants in traditional foods, many Inuit women eat increased amounts of these foods during pregnancy.
Genotoxicity and Cytotoxicity of Butadiene Soot
The toxicologic and epidemiologic consequences of exposure to environmentally relevant complex soots have not been well investigated. Catallo et al. (p. 965) conducted physico-chemical analysis of butadiene soot and detected hundreds of aromatic hydrocarbons and polycyclic aromatic hydrocarbons. A combination of moderate cytotoxicity and genotoxicity occurred in bronchial epithelial cells that could be considered pro-carcinogenic.
Metal Toxicants Released during Home Renovations
Because power sanding of old houses triggers lead poisoning and releases more than lead, Mielke et al. (p. 973) quantified the lead, zinc, cadmium, manganese, nickel, copper, cobalt, chromium, and vanadium in exterior paint samples collected from a home in New Orleans, Louisiana. The authors found an array of toxic metals in paint and stress that care should be taken during renovation to avoid the release of metal dusts into the environment. (Also see Science Selections, p. A434)
Hypersensitivity Pneumonitis: Residential Exposure
Apostolakos et al. (p. 979) discuss the case of a woman with a severe case of hypersensitivity pneumonitis caused by exposure to mold and thermophilic bacteria in damp areas of her home. Hypersensitivity pneumonitis has been associated with fungi, bacteria, and animal proteins, as well as a few industrial chemicals.
Last Updated: September 24, 2001
