Little hands touch everything, from faucets to fistfuls of playground sand in a day. What's the germiest spot?
Cleaning Surface Top
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These numbers represent colony-forming units (CFUs) per square inch. A CFU is a measurement of microbial organisms. The surfaces tested in our study contained everyday bacteria―most of which are not harmful to healthy people―and no traces of serious germs, like E. coli.

Store shopping cart: 2

Restaurant-restroom door handle: 4

Children’s library book: 7

Stuffed toy in a doctor’s office: 8

School-desk surface: 12

School computer mouse: 23

Store floor: 33

Public-park swing: 59

Restaurant tray: 204

School musical instrument: 262

Video-game controller in an arcade: 551

Public-park sandbox: 7,440

Classroom faucet handle: 32,000

Cafeteria water-fountain spigot: 62,000

Research was performed by NSF International Swab Testing, with thanks to Greta Houlahan and Robin Bechanko.