Unclean Colonoscopy Instruments: 3 in 20 Examined In Study Have "Dirt" From Colons

Unclean Colonoscopy Instruments:  3 in 20 Have "Dirt" from Colons  by Georffrey Mohan.  The Lost Angeles Times.  June 7, 2013.

(1)  The study was conducted by _______________________.

(2)  The study comes after improper cleaning practices at hospital resulted in patients having to undergo
___________ tests.

(3)  In May an Atlanta outpatient surgery center warned nearly 456 clients that they may have been exposed to ____________________.

(4)  About ______________ million American undergo colonoscopies each year.