Research Watch: PCBs in a lake - Environmental Science

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Research Watch Air Quality Metals in the atmosphere in Japan. In this study, the data from National Air Surveillance Network for selected crustal elements (Al, Ca, Fe, Mn, Sc, andTi), anthropogenic elements (As, Cu, Cr, Ni, Pb, V, and Zn), and a marine element (Na) in atmospheric particulate matter were evaluated over Japan from 1974 to 1996. (Var, E, et al. "The Concentration, Trend and Seasonal Variation of Metals in the Atmosphere in 16 Japanese Cities Shown by the Results of National Air Surveillance Network (NASN) From 1974 to 1996", Atmos. Environ. 2000, 34 {17), 2755-2770) Particulates in Chinese cities. X-ray diffraction and transmission analysis and polarizing optical microscopy were performed on low-volume particulate samples taken during 1998-1999 in the cities of Dongying, Jinan, and Qingdao in Shandong Province and in certain districts in Shanghai and Beijing. (Davis, B. L.; Jixiang, G. "Airborne Particulate Study in Five Cities of China", Atmos. Environ. 2000, 34 (17), 2703-2711)

Biodiversity Fish faunas similar in United States. Fish faunas across the continental United States have become more similar through time because of widespread introductions of a group of cosmopolitan species intended to enhance food and sport fisheries. (Rahel, F. J. "Homogenization of Fish Faunas Across the United States", Science 2000, 288 (5467), 854-856) Most diverse communities most likely to be invaded. A direct in situ manipulation of local diversity in a Californian riparian system and a

Novel cleanup of explosives Soils contaminated with high explosives such as TNT, RDX, and HMX pose significant risks to human health and the environment. Although incineration is the most effective remediation method, it is expensive, destroys soil fertility, and generates concern about air emissions. Recently, S. B. Hawthorne and co-workers investigated the use of subcritical water (hot water under sufficient pressure to maintain the liquid state) for treating these explosives-contaminated soils. In laboratory and pilot-scale tests, they achieved greater than 99.9% destruction of TNT and RDX and about 98% destruction of HMX. The authors report that the process is relatively low-cost ($125/ton compared to $125-S210/ton for composting, $220-$650/ton for supercritical water oxidation, and about $1600/ton for incineration), does not require use of any catalysts or additives, involves simple equipment, reaction conditions are easily controlled, and soil decontamination can be performed safely. {Environ. Sci. Technoi, this issue, pp 3224-3228)

seed addition experiment yielded results that suggest that species loss at small scales may reduce invasion resistance. (Levine, J. M. "Species Diversity and Biological Invasions: Relating Local Process to Community Pattern", Science 2000, 288 (5467), 852-854)

Biogeochemistry Ocean iron cycles. The authors incorporate a model of seawater iron geochemically into a global ocean circulation and carbon cycle model and tune it to match the observed ocean iron distribution. (Archer, D. E.; Johnson, K. "A Model of the Iron Cycle in the Ocean", Global Biogeochem. Cycles 2000, 14 (1), 269-279) Predicting DOC flux. The authors examined the relation between dissolved organic carbon (DOC) flux and soil C:N ratio using 15 biome types, including tropical rain forest, coniferous forests, peatland, deciduous forests, mixed forests, and grasslands. (Aitkenhead, J. A.; McDowell, W. H. "Soil C:N Ratio As a Predictor of Annual Riverine DOC Flux at Local and Global Scales", Global Biogeochem. Cycles 2000,14 (1), 127138)

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Climate Ozone increases. Significant increases of total ozone were observed both by the total ozone mapping spectrometer and by the Brewer spectrophotometer in Indonesia in 1994 and 1997, during the El Nino periods, when extensive forest fires were reported in Sumatra Island, the southern part of Borneo Island, and south New Guinea. (Kita, K., et al. "Total Ozone Increase Associated With Forest Fires Over the Indonesian Region and Its Relation to the El Nino-Southern Oscillation", Atmos. Environ. 2000, 34 (17), 2681-2690) Satellite measurements. Microwave SST retrievals provide insights in a number of areas, including tropical instability waves, marine boundary layer dynamics, and the prediction of hurricane intensity. (Wentz, F. J., et al. "Satellite Measurements of Sea Surface Temperature Through Clouds", Science 2000,288 (5467), 847-850)

Contaminants PCBs in a lake. Two dated sediment cores, one taken from the north basin and one from the south basin of Lake

Winnipeg (Manitoba, Canada), were analyzed for PCBs and organochlorine insecticides in order to examine the depositional history of these persistent organic pollutants. (Dorothea F. K., et al. "Historical Deposition of PCBs and Organochlorine Pesticides to Lake Winnipeg (Canada)",/. Great Lakes Res., 2000,26 (1) 3-17)

Drinking Water Disinfection byproducts. Natural organic matter containing many of the precursors to form undesirable disinfection byproducts following disinfection of drinking water was characterized in natural waters. (Marhaba, T. E; Pipada, N. S. "Coagulation: Effectiveness in Removing Dissolved Organic Matter Fractions", Environ. Eng. Sci. 2000,17 (2), 107-115) Lead in water. A simulation program was written to mimic the sampling process used to assess lead on a routine basis, the variability in water quality, differences in the housing stock, and customer characteristics. (Cardew, P. T. "Simulation of Lead Compliance Data", Water Res. 2000, 34 (8), 2241-2252.

Energy Molecular photovoltaic*. This review, with 49 references, confirms that die certified overall power conversion efficiency of the new solar cell for AM 1.5 solar radiation stands presently at 10.4%. (Hagfeldt, A; Graetzel, M. "Molecular Photovoltaics", Ace. Chem. Res. 2000, 33 (5), 269-277)

Metals Pigment substitutes. The authors demonstrate that solid solutions of the perovskites CaTa02N and LaTaON2 constitute promising candidates for cadmium pigment substitutes: their brilliance, tinting strength, opacity, dispersability, light-fastness, and heat stability rival that of the cadmium pigments, whereas their color can be tuned through the desired range, from yellow through orange to deep red, by simple composition ad-

Ships that pollute Nationwide emissions inventories from shipping have traditionally ignored shipping channels outside of port regions. In response to this issue, J. Corbett and P. Fischbeck examined emissions from waterborne commerce vessels in U.S. continental and inland waterways. N0X emissions from commercial marine engines were found to account for about 4% of all U.S. transportation emissions—more than double that of previous nationwide vessel emissions inventories. In many regions, N0X emissions from waterborne commerce ranked higher than other source categories regulated by state and federal statutes. The authors report that in the upper inland river system, Great Lakes, Northern Pacific Coast, and much of the Gulf Coast, 14-28 tons of N0X per mile each year is common and note that the number of automobiles that would produce an equivalent amount of N0X per mile of highway would range between 30,800 and 76,000 per day. (Environ. Sci. Technol., this issue, pp 3254-3260)

justments. (Jansen, M.; Letschert, H. R "Inorganic Yellow-Red Pigments Without Toxic Metals", Nature 2000, 404 (6781), 980-982) Trace metals. The authors analyzed samples of the oak, maple, willow, lime tree, and birch trees growing in a Wroclaw (Poland) urban area. (Prusisz, B.; Zyrnicki, W. "Study of Selected Major and Trace Metals in Various Trees From Urban Area", Environ. Prot. Eng. 1999, 25 (4), 91-99)

Modeling Combustion phenomena. Different levels of combustion modeling are identified and characterized in this review with several references, including some novel schemes for combustion large eddy simulation. (Candel, S., et al. "Progress in Numerical Combustion", Combust. Sci. Technol. 1999, 149 (1-6), 297-337) Discharge methods. The authors derived equations that allow a direct

comparison of the dynamic and steady-state methods for simple single-discharge situations. (Dilks, D. W.; Pendergast, J. F. "Comparison of Dynamic and Steady-State Models for Determining Water Quality-Based National Pollutant Discharge Elimination System Limits for Toxics", Water Environ. Res. 2000, 72 (2), 225229)

Soil Phosphate ions. Sorption, desorption, electro-ultrafiltration, and isotopic exchange studies show that an adequate modeling of the quantity of phosphate ions must account for both the concentration of phosphate ions in soil solution and time. (Morel, C , et al. "Transfer of Phosphate Ions Between Soil and Solution: Perspectives in Soil Testing", /. Environ. Qual. 2000, 29 (1), 50-59)

Water Aquatic ecosystems. This review, with 31 references, proposes a radical change in the present view on the nature of the self-purification capacity of aquatic ecosystems. (Kondrat'eva, L. M. "Secondary Pollution of Aquatic Ecosystems", Water Resour. 2000, 27 (2), 197-206) Indicator microorganisms. This study was conducted to assess the effects of temperature, salinity, dissolved oxygen, geographic location, season, and solar radiation on the survival of selected indicator microorganisms in estuarine waters. (Burkhardt, W, et al. "Inactivation of Indicator Microorganisms in Estuarine Waters", Water Res. 2000, 34 (8), 2207-2214) Phosphorus in rivers. This review, with 64 references, addresses the need to quantify the residence time of phosphorus within any particular part of a river system so that the specific contribution of individual P sources to biological demand can be determined. (Edwards, A. C , et al. "Assessing the Impact of Terrestrially Derived Phosphorus on Flowing Water Systems", /. Environ. Qual. 2000, 29(1), 117-124)

AUGUST 1, 2000 / ENVIRONMENTAL SCIENCE & TECHNOLOGY / NEWS • 3 5 5 A