In 1845 a well-equipped two-ship expedition led by Sir John Franklin sailed to the Canadian Arctic to chart the final unknown parts of the Northwest Passage. Confidence was high, as there was less than 500 km of unexplored Arctic mainland coast left. When the expedition failed to return, a number of relief expeditions and search parties explored the Canadian Arctic, resulting in final charting of a possible passage. Traces of the expedition have been found, including records that indicate that the ships became ice-locked in 1846 near King William Island, about half way through the passage, and were unable to extricate themselves. Franklin himself died in 1847 and the last of the party in 1848, after abandoning the ships and attempting to escape overland by sledge. While starvation and scurvy contributed to the deaths of the crew, another factor was significant. The expedition took 8000 tins of food which were soldered with lead. The lead contaminated the food, poisoning the crew. They would have become weak and disoriented--later stages of lead poisoning include insanity and death. In 1981, Dr. Owen Beattie, an anthropologist from the University of Alberta found signs of the expedition. This led to further investigations, and the examination of tissue and bone from the mummified bodies of three seamen, exhumed from the permafrost of Beechey Island. Laboratory tests revealed high concentrations of lead in all three bodies.
