Common household chemicals affect algae collected near the Olathe wastewater treatment plant on Cedar Creek River in Kansas. Inset shows a typical diatom from the river at 400x magnification.
News Briefs Wind keeps spinning up 2002 was another record year for wind power, with 6.8 gigawatts (GW) of new installations, according to the American Wind Energy Association (AWEA) and European Wind Energy Association (EWEA). Wind now supplies 0.4% of the world’s electricity demand. Most of the new turbines were erected in European Union nations, where the amount of wind-generated power jumped 33%. Germany has by far the greatest installed base of wind power, with Spain a distant second, and the United States close behind. India expanded its generating capacity by 13 GW last year and now ranks fifth in the world in installed turbines. For more information go to www.awea.org or www.ewea.org.
Economic slump aids emissions decline U.S. greenhouse gas emissions in 2001 dropped by 1.2% compared with 2000 emissions, according to the U.S. Energy Information Administration (EIA). The decrease marks the largest percentage annual decline in total greenhouse gas emissions from 1990 to 2001, according to EIA, which is part of the Energy Department. The decline is attributed to a combination of factors, including a reduction in overall economic growth from 3.8% in 2000 to 0.3% in 2001. U.S. emissions are nonetheless 11.9% higher than 1990 levels, but emissions have increased more slowly than primary energy consumption and gross domestic product. The report, Emissions of Greenhouse Gases in the United States 2001, can be found at ftp://ftp.eia.doe. gov/pub/oiaf/1605/cdrom/pdf/ ggrpt/057301.pdf.
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nutrients, the addition of toxic pollutants can lead to the extinction of sensitive species while concomitantly increasing the biomass of resistant species, says Smith. He draws that analogy of a lawn treated with an herbicide. In the extreme case, only a monoculture of grass would be left, but the lawn’s total biomass would be essentially unchanged. The result is less genetic diversity in the ecosystem. In rivers, addition of such pollutants could also mean the loss of a preferred or nutritionally better foods for organisms living on the algae, with a ripple effect all the way up the food chain. “[Rivers] could be left with a species-depauperate desert for consumers, containing few nutritionally adequate food items,” warns Smith. In this study, primarily conducted by Brittan Wilson in Smith’s group, algae growing in the Cedar Creek River were collected from both upstream and downstream sites of the Olathe WWTP in Kansas. Back in the laboratory, the algal cultures were spiked with one of the three target compounds, and their plant’s growth was compared with untreated algal suspensions. Wilson found that neither ciprofloxacin nor triclosan at the average concentrations found in U.S. streams by the USGS study (0.12 microgram-perBRITTAN WILSON; INSET: VALSMITH/W. DENTLER, UNIVERSITY OF KANSAS
ing streams. In a widely quoted study published last year, both triclosan and ciprofloxacin were found by U.S. Geological Survey (USGS) researchers in U.S. streams (Environ. Sci. Technol. 2002, 36, 1202–1211). “Many medicinal and pharmaceutical compounds are developed to exert an accurate effect on a specific organism during a well-defined period of time,” explains Alfredo Alder, with the Swiss Institute for Environmental Science and Technology. “But what happens in the environment, when these chemicals—albeit at a much lower concentration—act continuously on nontarget organisms?” Studies at the Universities of Guelph and Toronto have shown that high levels of a mixture of pharmaceuticals, including ciprofloxacin, affected organisms ranging from phytoplankton to sunfish (Environ. Sci. Technol. 2002, 36, 286A–287A). This new study investigated compounds separately and at concentrations closer to those found in the environment. “I use the terms ‘species turnover’ and ‘compensation’ to explain these findings,” says Val Smith, with the University of Kansas’s Department of Ecology and Evolutionary Biology and coauthor of the study. As species compete for light and
