Griffin, who worked in finance, had been on the island to raise US$100,000 ($118,000) for amyotrophic lateral sclerosis research.
A friend who was diagnosed with the neurodegenerative disease inspired Griffin to help create the charitable challenge.
The Ice Bucket Challenge has become a global phenomenon with everyone from pop star Justin Bieber to former US president George W. Bush and Microsoft founder Bill Gates drenching themselves in icy water.
And its popularity has spread around the globe, particularly to Britain, Australia, New Zealand, Canada and Germany.
Facebook said that between June 1 and August 17 more than 28 million people mentioned the challenge on the social network, and 2.4 million videos were posted.
The ALS Association said it had collected US$41.5 million in donations from July 29 to August 21 against US$2.1 million in the same period last year.
About 30,000 Americans have ALS, which attacks the nervous system and eventually leaves victims paralysed.