Toxicity of aerosol-bound PAHs Aerosol-bound polycyclic aromatic hydrocarbons (PAHs) are of concern because they are believed to be associated with cancer development in humans. Although the most studied PAH, benzo[a]pyrene, accounts for a significant fraction of the total mutagenic activity of urban aerosol extracts, investigators believe that other aerosol-bound PAHs may also play an important role. J. Allen and coworkers deter­mined the distribution of other C24HM PAHs as a function of particle size distribu­tion of urban aerosols. Results indicate that the total concentration of C24H14 PAHs is comparable to that of benzo[a]pyrene. The authors concluded that because of the mutagenicities of these compounds, C24H14 PAHs may make a contribution to the genotoxicity of urban aerosols that is comparable to that of benzo[a]pyrene. Observed distributions were found to have implications for human exposure. (Environ. Sci. Techno!., this issue, pp. 1928-1932)

braic/Graphical Tool To Compare Ecosystems With Respect to Their Pollution by Pb/Cd. Ill: Comparative Regional Analysis by Applying a Sim­ilarity Index," Chemosphere 1997, 36(3), 441-450)

Lead in peat bogs. Historical deposi­tion of lead in peat bogs can be re­lated to natural events and anthro­pogenic activity. (Weiss, D.; Shotyk, W; Cheburkin, A. K.; Gloor, M.; Reese, S. "Atmospheric Lead Deposi­tion From 12,400 to ca. 2,000 yrs BP in a Peat Bog Profile, Jura Moun­tains, Switzerland," Water, Air, Soil Pollut. 1997, i 00(3-4), 311-324)

Modeling Dissolved organic matter in the ocean. A biogeochemical general circulation model was developed, which includes dissolved organic matter production and consumption processes. (Yamanaka, Y.; Tajika, E. "Role of Dissolved Organic Matter in the Marine Biogeochemical Cycle: Studies Using an Ocean Biogeo­chemical General Circulation Mod­el," Global Biogeochem. Cycles 1997, 11 (4), 599-612)

Environmental contaminants. A review is presented of factors that are an incentive for applying mass balance modeling concepts toward elucidating sources, fate, and effects of contaminants in the environment. (Mackay, D.; Di Guardo, A.; Hickie, B.; Webster, E. "Environmental Mod­eling: Progress and Prospects," SAR QSAR Environ. Res. 1997, 6(1-2), 1-17)

Pesticides Chlorpyrifos hazard. Research has established that the semivolatile pes­

ticide will accumulate at high levels on and in toys and other sorbent home surfaces after application. (Gurunathan, S.; Robson, M.; Free­man, N.; Buckley, B.; Roy, A.; Meyer, R.; Bukowski, J. "Accumulation of Chlorpyrifos on Residential Surfaces and Toys Accessible to Children," Environ. Health Perspect. 1998, i06(l), 9-16)

Soil organisms and pesticides. A microcosm experiment was used to evaluate effects of patchy soil con­tamination by sodium pentachloro-phenate on decomposer organisms, their community regulation and nu­trient mineralization. (Salminen, J. E.; Sulkava, P. O. "Decomposer Communities in Contaminated Soil: Is Altered Community Regulation a Proper Tool in Ecological Risk As­sessment of Toxicants?" Environ. Pol­lut. 1997, 97(1-2), 45-53)

Risk Manganese-based fuel additive. The potential risks associated with use of the gasoline fuel additive, methylcy-clopentadienyl manganese tricar-bonyl, are summarized. (Davis, J. M.; Jarabek, A. M.; Mage, D. T; Graham, J. A. "The EPA Health Risk Assess­ment of Methylcyclopentadienyl Manganese Tricarbonyl (MMT)," Risk Anal. 1998, i8( l ) , 57-70)

Sediments Baltic Sea sediments. Metal concen­trations and other parameters were studied in suspended sediments that were taken from a basin in the east­ern part of the Baltic Sea, in die cen­tral Gulf of Finland. (Leivuori, M.; Vallius, H. "A Case Study of Seasonal Variation in the Chemical Composi­tion of Accumulating Suspended

Sediments in the Central Gulf of Fin­land," Chemosphere 1997, 36(3), 503-521)

Soils Carbon monoxide sink. Factors af­fecting the rate of CO utilization by soils were investigated in laboratory incubations and in the field using static chambers. (Moxley, J. M.; Smith, K. A. "Factors Affecting Utilization of Atmospheric CO by Soils," Soil Biol. Biochem. 1998, 30(1), 65-79)

Toxicity Sediment toxicity. Guidelines based on the bulk chemistry of sediments should not be used as indicators of sediment toxicity. (O'Connor, T. E; Daskalakis, K. D ; Hyland, J. L.; Paul, J. E; Summers, J. K. "Comparisons of Sediment Toxicity With Predictions Based on Chemical Guidelines," En­viron. Toxicol. Chem. 1998, i7(3), 468-471)

Waste Waste site survey methods. Results show that electromagnetic survey methods provide useful information for investigation of subsurface agri­cultural waste sites. (Eigenberg, R. A.; Korthals, R. L.; Nienaber, J. A. "Geophysical Electromagnetic Sur­vey Methods Applied to Agricultural Waste Sites," /. Environ. Qual. 1998, 27(1), 215-219)

Wastewater Biological phosphorus removal. A kinetic model for characterizing bio­logical phosphorus removal in se­quencing-batch and continuous-flow reactors is described. (Filipe, C.D.M.; Daigger, G. T. "Development of a Re­vised Metabolic Model for the Growth of Phosphorus-Accumulating Organisms," Water Environ. Res. 1998, 70(1), 67-79)

Contributors: Michael Brauer, University of British Columbia, Vancouver, Canada; Brian Eitzer, Connecticut Agricultural Experiment Station, New Haven, Conn.; Stephen Geiger, Remediation Technologies, Inc., King of Prussia, Pa.; Vincent Hand, Miami University, Institute of Environmental Sciences, Oxford, Ohio; Louis Kovach, Ecolife Associates, Wilmington, Del; Geoffrey Nobes, McGill University, Montreal, Canada; and Raewyn Town, Queen's University of Belfast, Northern Ireland.

JULY 1, 1998 / ENVIRONMENTAL SCIENCE & TECHNOLOGY / NEWS • 3 3 3 A