This is a reading comprehension exercise for children. It was written by Susan Fineman, a reading specialist in the New Haven, Conn., school district.

Guests of dentist Val Kolpakov are discouraged from brushing their teeth -- that is, with any of the more than 800 tubes of toothpaste in his collection.

Kolpakov started collecting toothpaste 10 months ago. The Saginaw dentist said he has spent about $3,000 to buy toothpaste tubes from Japan, China, India, Ukraine and his native Russia.

The collection takes up half of one of Kolpakov's bedrooms.

"When I have visitors, they sleep there with the fresh scent of toothpaste," said Kolpakov, 36.

Kolpakov said his goal is to have his collection listed in the Guinness Book of World Records as the world's largest.

He said that would mean squeezing past a German named Carsten Gutzeit, who claims on his Web site that he has 898 tubes but doesn't mention being listed in Guinness.

"I'm almost there. I'm pretty sure I have the most in the United States," Kolpakov said. "I'm moving really fast."

Kolpakov's oldest item is a Colgate tube from 1908. He also has a used tube found in Germany during World War II and a 1960s-era Scotch whisky-flavored toothpaste that has "no more than 3 percent alcohol."