Gordon Brown Escapes Student's Stickiness
Mr Glass - a 24-year-old post-graduate student at Strathclyde University - had smuggled a small amount ... in his underwear at about 1700 BST.
He met the prime minister during the reception at about 1830 BST.
"There may have been something sticky on his hands but it was only for a few seconds that he touched the prime minister," a spokesman said. "There was no stickiness of any significance."
Speaking afterwards, Mr Glass said: "My left hand was covered ...- it really hurt. He had to give it a couple of tugs before it came away. "
Mr Glass was invited to Downing Street to receive an award from the Sheila McKechnie Foundation for his protesting work with Plane Stupid.