Environmental ▼News Fish transport toxins hundreds of miles ushed hundreds of miles across migration route by tracking the fish ified fatty acids could have other the globe, pollutants often set400 km upstream into a pristine consequences. “We have research tle far from their origin beAlaskan lake. Once they reached that now shows that the fish can’t cause of wind, rain, or fire. Add to their lake, the salmon spawned and utilize these fatty acids because the that salmon. A study published in died. Ewald’s group then analyzed chlorine blocks enzyme digestion,” this issue of ES&T (pp 5548–5554) the levels of chlorinated fatty acids reports Ewald. has found that organohalogens in in Arctic grayling, which live in the Ewald has not done follow-up salmon migrating upstream to lakes. In the lakes where the salmstudies to see whether salmon mispawn in a lake can end up in on spawned, the grayling had 5 grations are causing chlorinated the lake’s resident fish. How compounds to build up in the this transfer occurs is still a lake, but Frank Wania, an enmystery. vironmental analytical chem“These fish spend about ist at the University of Toronto three years out at sea before (Canada), says the finding is their migration,” says Göran already important. “Studying Ewald, a professor of environthe transport process is itself mental science at the Techvery interesting, whether it nical University of Denmark leads to an enrichment of the and the corresponding author pollutants or not,” he says. for the new study. Once they While biotransport is probbegin migrating, the salmon ably not significant to the stop eating and deplete their movement of large amounts of Salmon migrate hundreds of miles from the ocean to fat stores by almost 95%, for pollutants on a global scale, it spawn in their natal rivers and lakes, but they also energy use. Previous studies may have important local eftransport any pollutants that have built up in their bodby Ewald and a report pubfects on pollution levels. And ies during years spent at sea. lished as an ASAP article in biotransport may be more September (es049607w) (and times the levels of chlorinated fatty prevalent in the environment than scheduled to be printed in the acids of graylings from a lake 2 km suspected. Ongoing research in December 1 ES&T special ecotoxiaway where salmon are not found. Norway has found that seabird cology issue) found that fat-soluble Ewald is not certain whether the droppings can contaminate lakes pollutants, such as PCBs and digraylings are acquiring the chloriunderneath a rookery with organobenzo-p-dioxins, become magninated fatty acids by consuming the chlorines, and an earlier paper (Enfied in salmon during this time of salmon roe or from feeding on the viron. Sci. Technol. 1993, 27, 2198– migration. For example, PCB levels dead fish themselves. 2206) reported that eels transport in the fat increase up to 9.7 times, “It has to be a direct transfer of large quantities of the pesticide Midepending on the migration run. fatty acids,” he says. He adds that rex out of the Great Lakes and up In the newest research, Ewald the levels of chlorine in the grayling the Saint Lawrence River, which adand his colleagues followed the were about 1 µg/g of fish, which is joins both Canada and the United salmon one step further along their not a toxic level. However, the modStates. —PAUL D. THACKER PHOTODISC
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Easing traffic and air pollution in London London is a city of superlatives: best theater, worst traffic, and most polluted air in Europe. However, “congestion charging”, which has been in effect for almost two years, may be improving the city’s air while re-
ducing traffic, encouraging purchases of energy-efficient automobiles, and funding public transportation, according to preliminary results presented at the World Clean Air and Environmental Protection
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Congress held in London in August. As of February 1, 2003, drivers who venture within an 8-squaremile area of Central London, bordered by the Inner Ring Road, on weekdays between 7 a.m. and 6:30 p.m. must pay a £5 fee. Signs emblazoned with a red and white C mark the pay-as-you-go streets. © 2004 American Chemical Society
RACHEL PETKEWICH
In London, C is for congestion charge. Drivers must pay a daily fee on weekdays to bring their cars into certain parts of the city.
in fleet composition in London have exceeded expectations, says Sean Beevers, a modeler in the Environmental Research Group at King’s College London. For the past 10 years, Beevers and his colleagues have been taking air measurements and modeling air quality around the city with the London Air Quality Network, a series of monitoring stations. Car and heavy-truck traffic in the area decreased by 30 and 11%, respectively, whereas bus and taxi traffic increased by 20 and 13%, respectively. Average car speeds were improved by 20%. This kind of traffic management gets cars moving in central London, and increased speed really reduces the pollutant emissions per kilometer traveled, the researchers report. As a result, nitrogen oxides and particulate matter less than 2.5 micrometers (measured as an aggregated number over 1.5- or 2-hour time periods) each decreased by 12%, and CO2 levels plummeted by 20%. The researchers believe that the increase in traffic speeds is at least as effective at reducing emissions as fewer cars on the road or improvements in vehicle technology between 2002 and 2003. “Certain people have to drive in London, such as delivery trucks, so let’s create an incentive for them to bring the cleanest vehicle,” says Colin Matthews, head of Transport Energy Programmes at the Energy Saving Trust, a U.K. nonprofit organization. He says people have bought hybrids and other clean cars, heavy trucks, and vans to take advantage of the discount available. Free-flowing traffic also reduced the number of accidents, he adds. Tom Downs, president of the U.S. nonprofit group Eno Transportation, notes that the key to success was to beef up public transport first. “London proved [cities] can’t simply price road access without creating options in advance.” —RACHEL PETKEWICH
News Briefs State of North Korea’s environment The Democratic People’s Republic of Korea faces significant environmental challenges, according to the first assessment of its environment, which was conducted by the United Nations Environment Programme (UNEP) and Korean authorities. When the report was released in late August, UNEP and the Korean government signed a framework agreement to guide joint activities in environmental protection, including projects to improve data collection and monitoring. The report calls for better protection of water resources. Other priorities are air pollution, forest depletion, and biodiversity protection. State of Environment DPR Korea 2003 is at www.rrcap.unep.org/ reports/soe/dprksoe.cfm.
Progress on PM A U.S. EPA report released in September describes the quantitative link between exposure to ambient particulate matter and morbidity and mortality, which is one of the major accomplishments of the Particulate Matter Research Program during the past five years. EPA scientists, university grantees, and other scientists at U.S. research institutions conducted the research summarized in the report, which the agency described as “part of a federally coordinated effort to define particulate matter health effects.” In 1997, EPA revised the National Ambient Air Quality Standards to set a standard for particles less than 2.5 micrometers after these pollutants were linked to cardiovascular problems. In 2004, EPA created additional regulations. Particulate Matter Research Program: Five Years of Progress is available at www.epa.gov/pmresearch.
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“Congestion charging is a way of ensuring that those using valuable and congested road space make a financial contribution,” according to Transport for London, the city’s transport authority. Certain vehicles are exempt from the charge—including taxis and emergency vehicles. Cameras monitor license plates. The owners of nonexempt vehicles who fail to pay the daily fee can be slapped with hefty fines. All the money collected pays for improvements to the bus and underground rail systems. The program has been generally viewed as a success, and in August, London’s mayor, Ken Livingstone, proposed expanding the congestion-charge area into Kensington, Chelsea, and Westminster. If accepted, charges in the new area would go into effect in 2006. London is not the first city to implement congestion charges. Singapore officials established their system in 1975 and updated it to electronic road pricing in 1998. Other cities have instituted similar charging systems on smaller scales. Traffic reductions and changes
