In the new study published in the Journal of Archaeological Science: Reports on December 6, researchers add credence to earlier conclusions that Franklin’s 129 crew members did not die of lead poisoning from canned food.
The study also suggests the expedition was running low on food supplies long before the ships became stranded in the ice. Their conclusions are based on the examination of nails from a crew member, John Hartnell.
“This is kind of like a Canadian myth,” said study co-author Laurie Chan, according to CTV News. “I get excited at the opportunity to work on it and talk about it.”
Nails reveal the crew’s eating habits
Two years ago, Jennie Christensen, an environmental consultant, thought it would be productive to use the latest laser technology to examine the Franklin Expedition corpses found on Beechey island in 1984.
She and Chan applied to the Museum of History in Ottawa and the Inuit Heritage Trust, who had custody of the bodies. They were eventually given a few nail clippings taken from able seaman John Hartnell. The toenail clipping was found to be contaminated, so the team turned to Hartnell’s thumbnail.
The researchers used lasers and the University of Saskatchewan’s synchrotron to peer inside the toenail. With the synchrotron, a source of brilliant light the scientists were able to gather information about the structural and chemical properties of the Hartnell’s nail at the molecular level.
It should be noted that different news agencies are reporting a toenail was the only nail used, while other news sources say the thumbnail was eventually used to get the results that were published. The actual study just uses the word “nails.”
The researchers used micro-X-ray fluorescence mapping, stable isotopic measurements and laser ablation inductively coupled plasma mass spectrometry to navigate through the piece of nail. After peering through the outer layers, the team got past any contamination and were able to get a clearer view inside the nail.
Our nails grow about three millimeters a month, and the researchers say Hartnell’s nail provided a “pretty good picture of what Hartnell had been eating and the state of his health in the last weeks of his life,” reports CBC.
Hartnell had a long-standing, severe zinc deficiency
The analysis of the nail revealed a severe deficiency of zinc in Hartnell’s body that probably lead to immuno-suppression and ultimately, tuberculosis and death. “That zinc deficiency would explain that he had a very low immune function,” Chan said. “In the tough environment, he probably contracted infections and died from [tuberculosis].”
The new study suggests that Hartnell was so sick and weak in the month before he died that his body released all the lead that had been stored in his tissues, leading earlier scientists to believe he had died from lead poisoning.
Lead poisoning was rather common in the 19th century because cans were soldered with lead, and poorly soldered cans leaked lead into the food sealed in the can. But according to the study, it was found that lead exposure actually decreased over the course of the expedition and Hartnell’s levels were within a healthy, normal range when he died.
One interesting thing mentioned in the study is that Hartnell appeared to have eaten very little meat on the voyage, despite there being large reserves of canned meat in the ship’s hold. “We see a clear decline of meat consumption,” said Chan. “If all the canned food (had lasted) he should not have that problem. It’s probably because some of the canned food was spoiled.”
Apparently, the crew didn’t resort to eating a lot of seafood, either. “We would expect, with the meat declining, he would eat a lot of seafood. But not really. Either he was not successful at getting seafood or they were just not able to do it,” added Chan.
We are cautioned that the findings in this study only apply to able seaman Hartnell, but Chan says they could be applied to the other crew members. Using the same technology would shed additional light on the Franklin Expedition.
