ation plans a court challenge and has asked for a temporary injunction to block enforcement. On Sept. 4 Mayor Washington ordered a halt to the use of leaded fuel in municipal vehicles. In Florida, the problem of ground water contamination is said to have reached crisis proportions. Espe cially affected is the Biscayne aquifer of southern Florida, which provides nearly all of Miami-Dade County's 300 million gal/day of water. Al though industrial chemicals are part of the cause, a major problem stems from the heavy use of artificial fertil izers to grow tropical fruits and win ter vegetables in a soil otherwise unsuited to farming. The water table lies within inches of the surface, particularly in southern Dade County where "rock plowing" pulverizes that thin layer to a workable grit, allowing easy contaminant access to the groundwater. Nine of 10 Florida residents, or nearly twice the national average, depend on groundwater for their water supplies.
EDUCATION ES& Τ advisory board member William Glaze has joined the fac ulty of the Environmental Science and Engineering Program at the University of California at Los Angeles. This program, which trains environmental managers, admits students with master's degrees in engineering, science, or public health. They broaden their back grounds with courses outside their specialties and become involved in courses covering real-world prob lems. These courses are in such areas as assessing the impact of offshore oil exploration or the relative risks of coal-fired vs. nuclear power plants. This semester, one course concerns the release of genetically engineered products into the environment.
year solar cycle," Gille observed. A correlation of solar UV output with ozone concentrations and the use of sun activity models suggest that the ozone concentration at the top of the layer, about 48 km above the Earth, may vary by 12% during each cycle.
leases of oil fogs and inert tracer gases will be monitored, and a threedimensional model of winds over the mountain area will be generated.
TECHNOLOGY
A challenge to some aspects of cancer progression theory has arisen at Argonne National Labora tory (ANL). Biochemist Carl Peraino and his colleagues now believe that carcinogenic agents first cause "foci" to be formed among a target site's cells. These become tumors not through a progressive increase in complexity but as the result of "a specific, but unknown cellular trans formation event distinct from events leading to focus formation." The change could occur simultaneously with or following the inducement of foci. The ANL scientists proposed this hypothesis after experiments on rats using 2-acetylaminofluorene and other carcinogens, with phénobarbital as a promoter.
Enzymes may be used to detoxify or deactivate hazardous chemicals, Gordon Williams of Battelle (Richland, Wash.) suggested to a meeting of the American Institute of Chemical Engineers. He noted that enzymes do not require "caustic and sometimes dangerous chemicals" used in chemical treatments, and their use in contaminated soils would prevent the danger caused by physical removal and storage of these soils in contained areas. Moreover, the release of enzymes does not generate the same concern for public safety that is caused by releasing genetically engineered organisms. Williams cautioned that the usefulness of enzyme treatments would depend on the availability of industrial processes for cost-effective enzyme production.
A meteorological study directed at a better understanding of pollutant dispersion in mountainous areas is being coordinated by Lawrence Livermore National Laboratory. With funding of $1 million from the Department of Energy, the study will take place mainly at night, over a three-week period. The study area, about 40 miles northeast of Grand Junction, Colo., is in the heart of massive oil shale reserves. Acoustic sounders and tethered and free-flying balloons carrying complex instrumentation will measure wind velocities, temperatures, and pollutant flows in and around a valley. Re-
Microalgae could be used as a fuel source, according to the Solar Energy Research Institute (SERI, Golden, Colo.). These organisms contain lipid oils composed of fatty acids and triglyceride compounds, which can be converted into alcohol esters by conventional technology. The esters, in turn, can be blended with diesel fuel (up to 30%) without affecting engine performance. Other products obtainable include alcohols, organic acids, and methane. SERI estimates a possible commercial microalgae biomass yield of 66,000 kg/ha-y, compared with 1326 kg/ha·y for sunflowers. Sunflowers
Microalgae-to-fuel sytem
SCIENCE Changes in ultraviolet (UV) rays from the sun can alter stratos pheric ozone concentrations, John Gille and his associates at the Na tional Center for Atmospheric Re search reported in Science (Vol. 255, p. 315). Measurements made by the Nimbus 7 satellite showed a 0.260.6% variation in tropical stratos pheric ozone every 13.5 days during a 5-month period. Although that change is small, "the finding implies a much greater effect over the 11-
Source: SERI
Environ. Sci. Technol., Vol. 18, No. 11, 1984
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