effects, from crossed bills and oddplumage patterns to an inabilityto construct proper nests.

The federal government listsPCBs as probable carcinogens,but that may not be their mainharm. “Many of the symptoms inhumans exposed to PCBs are re-lated to the nervous system andbehavior,” writes David O. Car-penter, coordinator of the Akwe-sasne research team and a dean atthe State University of New Yorkat Albany. Some congeners killbrain cells in lab tests; they espe-cially seem to affect dopamine, akey brain chemical.

Bush’s lab had begun accumu-lating evidence that suggests PCBscould be more harmful than pre-viously realized. For instance, itfound how easily some forms ofPCBs become airborne. Since atleast 1937, PCBs have been known tovolatilize, but no one had tested wheth-er breathing in PCBs harms humans.Moreover, no one knows how far air-borne PCBs can travel. Researchers inCanada found that the breast milk ofInuit women in northern Quebec washeavily contaminated with PCBs. Ex-posure was traced to precipitation thatreleased PCB fallout: the compoundsreturned up the food chain through fishand seals, which serve as the Inuits’ pri-mary food. Bush speculates that thePCBs may have come from New York’sHudson River. Because the river is an es-tuary, each turn of the tide exposes mud-flats, from which PCBs may rapidly vol-atilize and move off in the air currents.

Bush’s pronouncements of the dan-gers from the airborne spread of PCBsfly in the face of inaction by state healthofficials and claims made by the corpo-rations that dumped PCBs, such as Gen-eral Electric. The firms have consistent-ly maintained that the chemicals lie in-ert at river bottoms and at dump sitesand thus are basically harmless in theenvironment. If further research sup-ports Bush’s contentions, then GE andother companies may become liable forbillions of dollars in cleanup costs.

That research, though, may not hap-pen soon. Last September Bush receiveda memo from his superior, stating thathe was being transferred to a new as-signment, one unconnected with PCBs.According to some of Bush’s colleagues,the move forces the cancellation of somegrants, which require a level of investi-gator expertise (without Bush, the team

lacks the necessary aptitude). That hasalso created a ripple effect: SheldonFeldman of the Benedictine Hospital inKingston, N.Y., who studies the relationbetween PCBs and breast cancer, said hehad no place to send samples.

The memo did not explain the move,but health department spokespersonslater hinted that Bush’s lab work wasdeficient. The department appointed afive-member committee to investigate,and in December it released what itcalled a consensus report. The four-pageaccount was critical of some proceduresin Bush’s lab, noting in summary that“proficiency has been hampered by alack of proper quality control/quality as-surance procedures and a lack of prop-er data review procedures.”

Bush says the report effectively exon-erates his work, claiming that his over-all conclusions are not challenged. Com-mittee members never actually visitedhis lab, he said, but spent a day goingover paperwork. They found three er-rors in more than 6,500 data pointsculled from 63 blood and serum sam-ples. “They are trying to get me becauseI am a whistle-blower,” Bush insists.“But I consider the whole thing as a tri-umph, because the whole line that PCBsare innocuous has been blown sky-high.”

After the release of the report, S.U.N.Y.at Albany offered to set up a laboratoryfor Bush, enabling him to conduct PCBresearch on the Albany campus. Bushhopes to resume his studies soon, butnothing is set. Meanwhile we remainuncertain how much harm we inhale.

—Jim Gordon in Saugerties, N.Y.

News and Analysis22 Scientific American February 1998

Black Hole BlastsOnly MERLIN—the Multi Element RadioLinked Interferometer Network—couldhave captured the event: In late October

the instrument, whichis run by the Universityof Manchester, record-ed a series of explo-sions coming fromGRS1915, a black holesome 40,000 light-years away on the oth-er side of the MilkyWay. Matter spiralinginto GRS1915, which isseveral times moremassive than our sun,violently shot out two

streams of ultrahot gas. These jetsmoved in opposite directions at veloci-ties greater than 90 percent of thespeed of light.

Biotic BargainDavid Pimentel and eight graduate stu-dents at Cornell University’s College ofAgriculture and Life Sciences recentlyfigured the tab for services we get freefrom the planet’s plants, animals andmicroorganisms. The total came to$319 billion for the U.S. and $2.9 trillionfor the world. Some of the charges:

Extending LifeNew clues about the genetics of agingare emerging. First, Cynthia Kenyon ofthe University of California at San Fran-cisco reported in Science that the activi-ty of a single gene can double the lifespan of the nematode C. elegans. Thegene, daf-16, is related to so-called fork-head genes, which encode tined pro-teins that can attach to and controlstretches of DNA. Second, Marc Tatar ofBrown University, working with col-leagues from the University of Minneso-ta, published results in Nature showingthat flies bred to contain extra copies ofheat-shock protein 70 produce a lot of itwhen they are exposed to warmth, andthis abundance substantially increasestheir life span.

IN BRIEF

AIRBORNE PCBs FROM SOIL could pose a hazard, Brian Bush argues.

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Sunrise is two hours away, and it’sas dark as it should be with themoon obscured by clouds. Lisa

Borgia tromps knee-deep through ahalf-acre pond about 20 miles west ofWest Palm Beach, the beam from aheadlight perched atop her mosquitohood slicing the gloom. She admits thatshe prefers Star Trek’s ridge-headedKlingon Mr. Worf to Brad Pitt, whichmay help explain why Borgia, on an in-ternship with the South Florida WaterManagement District (SFWMD), re-mains unperturbed by the alligatorwhose head breaks the surface six feetaway. Granted, the reptile is only abouttwo feet long; the big gators eschew thepond, and a more likely source of trou-ble is the venomous snakes. Even takingWorf into account, the obvious ques-tion—What’s a nice girl like you doingin a place like this?—takes a backseat toa more immediate query: Why is shecarrying those plastic lawn flamingos?

Borgia, fellow flamingo-bearer DavidK. Kieckbusch and their boss, avianecologist Dale E. Gawlik, a senior envi-ronmental scientist with the SFWMD,have finally found a constructive usefor the pink lawn ornaments. A coat offlat white paint transforms the subur-ban blight into tools for studying howbirds use visual cues from their feath-ered friends to choose feeding sites.

The SFWMD’s 15 ponds are perfect-ly situated for controlled field researchon wild subjects—egrets, herons, ibis andwood storks naturally fly in from theadjacent Loxahatchee National WildlifeRefuge. “We focused on things like wa-ter depth and prey density,” Gawlik saysof earlier, flamingo-free experimentsaimed at teasing out the relation be-tween wading birds and water supply.The researchers altered environmentalfactors in the ponds easily—gravity flowfrom a higher reservoir or into a lowerone changes the water level of any pondin minutes. But some of the social cuesthat determine feeding choices amongwading birds remained unknown.

Perhaps decoys could reveal how birdsrely on their feathered friends for din-ing recommendations, the researchersthought. When Borgia found out thathunters’ heron decoys run a prohibitive$30 each, she consulted with Kieck-busch, who had pink flamingos at home,and discovered that the plastic lawn or-naments could be had for $5.40 a pair.Painted, they make passable egrets.

Previous trials using the fake flamin-gos showed that birds bypass emptyponds in favor of those with decoys.This mid-November day’s experimentwill fine-tune the data. Borgia andKieckbusch set the lawn decorations ineither scattered or clustered arrays inponds of various depths. “The spacingof the flock is an additional cue relatedto social behavior,” Gawlik says.

As we move through the water—afast, bowlegged waddle helps to mini-mize sinking into the soft bottom—themosquitoes attack mercilessly. As wellas a nuisance, they’re probably more

News and Analysis Scientific American February 1998 23

Come and Get ItIn December the Food and Drug Admin-istration at last approved the use of radi-ation for eliminating harmful microor-ganisms such as E. coli from red meat.For years, companies have irradiatedchicken, fruits andvegetables, butthere has beenlittle consumerdemand forthem. They aremost often pur-chased for astro-nauts and hospital pa-tients—for whom food poisoning couldbe especially deadly. But several recentoutbreaks have made irradiated meatsmore popular. Treated meat packages,which will bear the label shown here,most likely will appear in markets nextsummer and should cost only a fewcents more than nonirradiated meats.

Snowball FightPhysicists at the fall meeting of theAmerican Geophysical Union had it outagain over the theory that small icecomets continually pelt our planet’s up-per atmosphere. Louis A. Frank andJohn B. Sigwarth of the University ofIowa presented new evidence in sup-port of the idea, which they first pro-posed 11 years ago. They showed thatdark spots on photographs taken byNASA’s Polar spacecraft change in sizedepending on their distance from thecameras—which is just what you wouldexpect if the spots marked real comets.But James Spann of the NASA MarshallSpace Flight Center argues that the darkspots are simply noise from the camerasand that they also appear when the in-struments are on the ground. Only timeand more data will tell.

Asbestos EaterSounds too good to be true: Scientistsat Brookhaven National Laboratory,working with W. R. Grace & Company,have developed a chemical solutionthat can destroy asbestos in installedfireproofing without ruining the materi-al’s ability to resist fire. When this foamwas sprayed onto fireproofing made byGrace, it dissolved asbestos fibers intoharmless minerals. Because it eliminatesthe need to remove the older material,the process should reduce costs forbuilding owners. Patents are pending,and the product, which should work onall kinds of fireproofing, is expected tobe commercially available by early 1998.

More “In Brief” on next page

THE PAINTED BIRD

Lawn flamingos come to the aid of ecology

FIELD NOTES

PLASTIC FLAMINGOS (foreground) bring in ibis.

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News and Analysis24 Scientific American February 1998

Blowing across the lip of a bottleto produce that satisfying humwould not seem to be the basis

for new discoveries. But that is essential-ly what Timothy S. Lucas claims he hasmade. Reporting at the Acoustical Soci-ety of America meeting last December,the founder and president of Macro-

Sonix Corporation in Richmond, Va.,says his torpedo-shaped

“bottles,” when

shaken back and forth hundreds of timesa second, can create standing soundwaves within them that pack energydensities 1,600 times greater than thatpreviously achieved in acoustics. Theprocess, which Lucas calls “resonantmacrosonic synthesis,” can producepressures exceeding 3.5 million pascals(500 pounds per square inch), morethan enough for industrial applicationssuch as compressing and pumping.

The key is the shape of the bottle, orresonator. In the past, resonators wereoften cylindrical, and shock wavesformed inside them if they vibrated tooquickly. A shock wave—a compressionwave that delineates a sharp boundarybetween high and low pressures—dissi-pated energy, preventing the internalpressure from getting too high. As a re-sult, driving the resonator faster—theequivalent of blowing harder across thetop of a bottle—would no longer boostthe volume of the internal sound.

After KyotoIt took 11 marathon days of negotia-tion, but at last on December 11, dele-gates at the Third Conference of theParties to the United Nations Frame-work Convention on Climate Change in

Kyoto reachedan agreementto curb green-house gasemissions inthe near future.Many chargethat the treatydid not go farenough and

that emissions levels will not fall off fastenough to prevent catastrophic globalwarming. Yet it is unclear whether all ofthe more than 150 participating coun-tries will ratify the treaty. The U.S., whichcame away from the table having wonless commitment from developing na-tions than it had wanted, has promisedto cut emissions back to 7 percent be-low 1990 levels. The European Unionpledged 8 percent cuts, and Japansigned on for a 6 percent reduction.

Particle AcceleratorFor the first time, materials and partsmade in the U.S. will be used in a parti-cle accelerator outside the country. In-deed, more than 550 U.S. scientists arecollaborating on two massive detectorsfor the Large Hadron Collider—a parti-cle accelerator, measuring 27 kilome-ters in circumference, now under con-struction at CERN, the European labora-tory for particle physics near Geneva.The Large Hadron Collider will crashprotons into one another at higher en-ergies than ever before.

Checkout TechYou’re next in line, but the guy in frontof you is buying some odd piece of fruit,for which the cashier can’t seem to findthe right scale code. A new gadgetcould save you from supermarket hell:Alan Gelperin of Princeton, N.J., hasbeen awarded a U.S. patent, which heassigned to NCR Corporation in Dayton,Ohio, for a device that senses the aro-mas of familiar produce. An induced air-flow wafts past a fruit or vegetable andenters an aperture in the device, acti-vating sensors that prepare a patternaccording to the smell. The device thencompares the pattern with referencesand rings you up. —Kristin Leutwyler

In Brief, continued from preceding page

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ACOUSTIC “BOTTLE”driven by a motor breaks a sound barrier.

dangerous than the gators and snakes:the area is under an encephalitis watch.“If you face into the wind,” Borgia ad-vises this slap-happy reporter, “the mos-quitoes will gather on your lee. You cankeep them off your face.” Flamingosset, Borgia and Kieckbusch climb to thedecks of separate observation towers,each with a view of half the ponds.

Shortly after first light, real birds jointhe plastic ones. Like an overwhelmedair-traffic controller, Borgia franticallyrecords the arrivals and departures:“Glossy ibis and tricolor heron leaving[pond number] 8. . . . Two little blueherons on 9.. . . Large group of snowiescoming in to 8, estimate 60.. . . Greatblue on 11.. . . Two glossy ibis on 11.. . .One great and one snowy leaving 11.”

The attempt to note the decisions ofhundreds of birds continues for almostan hour, by which point the sheer num-ber of real birds drowns out the decoyeffect. Borgia and Kieckbusch abandontheir roosts and head back into themuck to wrangle the flamingos. Theywill randomize the water levels and ar-

rays and repeat the experiment all week.Then they and Gawlik will analyze thedata, hoping to fill in another small pieceof the large puzzle that is the Evergladesecosystem. Water management decisionscritical for the region’s wildlife and peo-ple depend on such detailed informa-tion. The lowly lawn flamingo finallyhas reason to preen. —Steve Mirsky

BOOM BOX

A resonator boosts sound pressures to new highs

ACOUSTICS

AFTER THE MORNING COUNT Lisa Borgia rounds up the decoys.

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