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Number of U.S. businesses and organizations supported

by recycling: 56,000

Number of people employed:1.1 million

Annual payroll:$37 billion

Annual government revenue throughtaxes on recycling industries:

Federal: $6.9 billion

State: $3.4 billion

Local: $2.6 billion

New York City’s daily recycling haulof metal, glass and plastic:

1,100 tons

Amount city will save by abandoningsuch recycling for 18 months:

$56 million

S O U R C E S : “ U . S . R e c y c l i n g E c o n o m i cI n f o r m a t i o n S t u d y , ” N a t i o n a l R e c y c l i n g

C o u n c i l , J u l y 2 0 0 1 ( c o m m i s s i o n e d b y t h eU . S . E n v i r o n m e n t a l P r o t e c t i o n A g e n c y ) ;N e w Y o r k C i t y D e p a r t m e n t o f S a n i t a t i o n

DATA POINTS:WASTE FOR MONEY

E C O L O G Y

Kermit Had It Easy Researchers may have pinpointed two fac-tors contributing to the worldwide decline infrog populations. Pieter T. J. Johnson of theUniversity of Wisconsin–Madison, An-drew R. Blaustein of Oregon State Uni-versity and their colleagues ob-served that the frequency andseverity of deformities commonto frogs in some parts of theAmerican West depended solelyon the prevalence of the para-sitic flatworm Ribeiroia onda-trae. Ribeiroia is carried byaquatic snails, whose numbers,the researchers say, may be climb-ing because of increased nutrientsfrom fertilizer runoff, among otherfactors. If that weren’t enough, when bi-ologists at the University of California atBerkeley bathed male tadpoles in the popu-lar herbicide atrazine, the croakers tended togrow female sex organs inside their testes andhad smaller vocal organs. The reason may be

that atrazine converts testosterone into estro-gen, although the scientists note that atra-zine’s effect on reproduction itself still isn’t

clear. The parasite study is published in theMay Ecological Monographs, and the atra-zine research appears in the April 16 Pro-ceedings of the National Academy of Sciences.

—JR Minkel

P H O T O N I C S

White Light, Less HeatThe average incandescent lightbulb sheds farmore heat than light—90 percent of its energy islost as heat. Even high-efficiency fluorescentbulbs essentially burn away roughly half theirpower. The future may prove brighter—and cool-er—thanks to microscopic filaments being de-signed by researchers at Sandia National Labora-tories. These filaments are photonic crystals, inter-woven layered substances that control light waves

the way semiconductorscontrol electrons. The sci-entists have made 1.5-mi-cron-wide tungsten pho-tonic crystals that absorbinfrared energy, which inturn might be transmutedefficiently into visible orultraviolet light. The re-search can be found in theMay 2 Nature.

—Charles Choi

G E N E T I C S

Mutation KeepsGoing and GoingIt’s no surprise that mice exposed to ra-diation can pass on genetic mutations.But researchers were puzzled two yearsago to see that the offspring of irradiat-ed male mice had higher-than-normalmutation rates in genes they receivedfrom their unexposed mothers. Con-firming and extending their earlier re-sult, Yuri E. Dubrova and his colleaguesat the University of Leicester in Englandnow report that this effect extends downto all the grandchildren of three strainsof male mice exposed to mutation-caus-ing neutrons or x-rays. They infer thatthe radiation introduces a signal inde-pendent of any particular gene that caus-es the whole genome to accumulate er-rors, but beyond that, Dubrova says,he’s stumped. The study appears in theMay 14 Proceedings of the NationalAcademy of Sciences. —JR Minkel

FLATWORMS seem to be causing frog deformities.

PHOTONIC filament

COPYRIGHT 2002 SCIENTIFIC AMERICAN, INC.