Cancer study checks toenails for arsenic
'A little window back in time'
Last Updated: Wednesday, November 4, 2009 | 4:11 PM AT
CBC News
The amount of arsenic in toenails is being measured by medical researchers trying to find out why Nova Scotia has some of the highest cancer rates in the country.
The arsenic and old toenails study is just one piece in a much bigger scientific puzzle but it's an important one, said epidemiologist Louise Parker, head of population cancer research with the provincial division of the Canadian Cancer Society.
"Yesterday nine men and seven women in Nova Scotia received the shattering news that they had cancer," she said Tuesday. "I want to know why we have so much cancer so we can do something about it."
Parker noted that Nova Scotia is basically a big rock sticking out of the sea and its geology has high levels of arsenic, a toxic mineral that is easily carried into water supplies and is known to be linked to bladder and kidney cancers.
"So, when we then go along and dig our wells and extract that water for our drinking water, we may be exposed to water which has high levels of arsenic," she said.
About 45 per cent of Nova Scotia households get their drinking water from wells.
The toenail clippings are provided by volunteers, Parker said, and there is always room for more. Since toenails grow slowly, by the time the clippings end up in the scientists' sample they are already old, she said.
"So the toenail gives a little window back in time to look at how much arsenic you have been exposed to, and how much you have accumulated in your body over the last nine months or so," Parker said.
If arsenic turns out to be a link in the cancer puzzle, she said, it could also become an important piece of the cure by preventing exposure in the first place.
