nent of programs designed to reduce blood lead levels. (Schultz, B.; Pawel D.; Murphy, A. "A Retrospective Examination of In-Home Educational Visits To Reduce Lead Levels," Environ. Res. 1999, 80 (4), 364-368)
MEASUREMENTS Oceanic particle characterization. Applying flow cytometric sorting and direct temperature-resolved mass spectrometry to oceanic particulate organic matter samples can bridge the gap between information available from bulk measurements, such as elemental analyses, and information derived from detailed, but laboriously compiled, class-specific analyses. (Minor, E. C; Eglinton, T. I.; Boon, J. J.; Olson, R. "Protocol for the Characterization of Oceanic Particles via Flow Cytometric Sorting and Direct TemperatureResolved Mass Spectrometry," Anal. Chem. 1999, 71 (10), 2003-2013)
MODELING Ambient sulfur concentrations. The adaptation of a regional Lagrangian approach for making longterm simulations of S0 2 and sulfate ambient concentrations at the resolution needed for health effects risk assessment in Asian megacities and their surroundings is explored. (Calori, G.; Carmichael, G. R. "An Urban Trajectory Model for Sulfur in Asian Megacities: Model Concepts and Preliminary Application," Atmos. Environ. 1999, 33 (19), 3109-3117)
PESTICIDES Exposure assessment. Four different mixing-loading and application practices in potato fields were measured individually to assess their relative contribution to the total exposure of pesticide users. (Vercruysse, E; Drieghe, S.; Steurbaut, W.; Dejonckheere, W. "Exposure Assessment of Professional Pesticide Users During Treatment of Potato Fields," Pestic. Sci. 1999, 55 (4), 467-473)
Polybrominated diphenyl ethers synthesized Polybrominated diphenyl ethers (PBDEs) are produced industrially and are used widely as flame retardant additives—the estimated global consumption of PBDEs in 1992 was 40,000 metric tons. Recent data suggest that this substance class may be more harmful than previously believed—for example, 2,2',4,4',5-pentabromo diphenyl ether has been reported to induce learning disabilities in mice. Increased knowledge of the physical chemical parameters of PBDEs can aid in their identification and quantification in environmental samples and support assessments of their toxicity. In support of this objective, G. Marsh and colleagues synthesized and characterized 32 PBDEs, and report melting points as well as UV, 1H NMR, and mass spectra. {Environ. Sci. Technol., this issue, pp. 3033-3037)
SOILS
PAHs. The genotoxicity of two polycyclic aromatic hydrocarbons was experimentally shown to decline after aging in soil for 7 to 15 days, with little or no loss of the compounds. (Alexander, R. R.; Alexander, M. "Genotoxicity of Two Polycyclic Aromatic Hydrocarbons Declines as They Age in Soil," Environ. Toxicol. Chem. 1999,18 (6), 1140-1143)
TOXICOLOGY Neural network-based modeling. A model based on probabilistic neural networks without using the octanol-water partition coefficient is applied to the estimation of toxicological effects of chemicals on the fathead minnow. (Kaiser, K. L. E.; Niculescu, S. P. "Using Probabilistic Neural Networks To Model the Toxicity of Chemicals to the Fathead Minnow {Pimephales promelas): A Study Based on 865 Compounds," Chemosphere 1999, 38 (14), 3237-3245)
WASTEWATER
PCDD/F levels. Soil samples collected near an old municipal solid waste incinerator in Spain were analyzed to determine the temporal variation in polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran levels. (Domingo, J. L; Schuhmacher, M.; Granero, S.; Iiobet, J. M.; De Kok, H. A. M. "PCDD/F Levels in the Vicinity of an Old Municipal Solid Waste Incinerator: Temporal Variation in Soils," Arch. Environ. Contam. Toxicol. 1999, 36 (4), 377-383)
TOXICITY Aquatic biomarker. The p53 gene was sequenced from five fish species with a view to the possible use of mutations in the highly conserved domains of p53 to identify genotoxins in the aquatic environment. (Bhaskaran, A.; May, D.; RandWeaver, M.; Tyler, C. R. "Fish p53 as a Possible Biomarker for Genotoxins in the Aquatic Environment," Environ. Mol. Mutagen. 1999,33 (3), 177-184)
Industrial effluents. Technologies and tests that enable water utilities to monitor sewage treatment and water treatment works intakes to identify and apply consent limits on pollution sources or to automatically switch to enhanced processes or diversion mechanisms are discussed. (Fearnside, D; Caffoor, I. "The Detection of Pollution: Some Novel Approaches,"£>iwron. Toxicol. Water Qual. 1998,13 (4), 347-357)
WETLANDS Early pollution indicators. A review of rapid assessment techniques for determining wetland degradation describes the ideal attributes of early warning indicators and evaluates the potential of existing assessment methods. (Van Dam, R. A.; Camilleri, C; Finlayson, C. M. "The Potential of Rapid Assessment Techniques as Early Warning Indicators of Wetland Degradation: A Review," Environ. Toxicol. Water Qual. 1998,13 (4), 297-312)
SEPTEMBER 1, 1999 / ENVIRONMENTAL SCIENCE & TECHNOLOGY / NEWS • 3 8 1 A