The documentary, Downstream by California-based filmmaker Leslie Iwerks, shines the spotlight on Dr John O'Connor, who two years ago highlighted findings of a rise in the number of patients with a rare cancer of the bile duct, as well as other cancers, in Fort Chipewyan.

Dr O'Connor, who is from Assumpta Park in Limerick city, emigrated to Canada in the 1980s and maintains a general practice in Nova Scotia, but also flies to visit patients thousands of miles away in Fort Chipewyan, a community in Alberta.

Described as the "flying doctor" in Fort Chipewyan, the community is downstream from an oil-sands development and forestry mills, which many in the area believe have contributed to contamination of water and wildlife.

After raising concerns about the number of cancer patients in the area, Dr O'Connor called for a thorough health review of the community.

However, in what was perceived as an attempt to muzzle him, Health Canada doctors lodged five complaints against Dr O'Connor with his professional body – charges which could have resulted in the loss of his licence.

But in March 2007, the Alberta Medical Association passed a unanimous motion supporting Dr O'Connor.

Now however, American media reports have stated that the incident has made Dr O'Connor "a celebrity of sorts".

Downstream was among eight films shortlisted for an Oscar for best short documentary by the Academy of Motion Picture Arts and Sciences last week. Three to five of the shortlisted documentaries will earn nominations for the 81st Academy Awards next year.