Lab holds largest assortment of toenail clippings – with over 30,000 individuals donating samples

When it comes to toenail clippings, do you put them in the bin, flush them down the toilet, or throw them out the window?

Or, do you send them to a research facility?

While this last option may sound strange, 30,000 Canadians have indeed cut their toenails, scooped up the shards and dropped them into clear bags to put in the post.

In fact, the collection – housed at Dalhousie University in Nova Scotia – is in the book of Guinness World Records as the largest collection of toenail clippings.

But rest assured, the clippings represent a serious a scientific study rather than a creepy personal collection. 

Scientists say toenail clippings give a measure of the potentially toxic elements that we have been exposed to in the past few months, such as arsenic. 

Toenail analysis, combined with a knowledge of where each donor lives, can reveal specific locations where potentially dangerous chemicals are high. 

Professor Trevor Dummer, health geographer at Dalhousie University, told MailOnline: ‘Toenails are in individual plastic bags stored in filing cabinets – no special freezers or storage units required.

Around 30,000 Canadians have indeed cut their toenails, scooped up the shards and dropped them into clear bags to put in the post (file photo)

30,000 Canadians have cut their toenails, scooped up the shards and dropped them into clear bags to put in the post

‘When a toenail is able to be clipped it’s on average about 10 to 14 months old. 

‘Some environmental contaminants and heavy metals – including arsenic – are preferentially deposited in toenails.

‘They have an affinity for keratin so naturally attracted to it through human biology.’ 

The Atlantic Partnership for Tomorrow’s Health (PATH) is part of the Canadian Partnership for Tomorrow Project, the largest study of its kind undertaken in Canada. 

It is investigating the various factors that contribute to the development of cancer and chronic diseases, including the longer-term health impacts of arsenic.

For example, long-term exposure to arsenic from drinking water and food can cause cancers, but is also linked with cardiovascular disease and diabetes. 

Because the toenails are around one year old when clipped, they are a good indicator of past or longer term (‘chronic’) exposures to arsenic and other heavy metals. 

‘Participant toenails are processed individually so we can get a good estimate of metals body burden for each individual and then we can look at associations with health outcomes,’ said Professor Dummer. 

‘We also have geocoding information – i.e., address details – so we can assess someone’s metals body burden in relation to the environment where they live.’ 

If you’re wondering why they don’t just take urine samples instead, most arsenic is excreted through urine within 48 hours. 

‘With urine the arsenic is removed from the body quickly, so urine is by contrast more useful for acute exposures,’ added Professor Dummer. 

In 2013, the project received a mention in the Guinness Book of World Records for the largest collection of toenails – representing 24,999 people. 

Since then the collection has still been growing, but the most recent count was 30,686.

The remarkable project has given thousands an answer something to do with their toenail clippings, which remains a bit of a conundrum for the general public. 

There’s a lack of official advice about what to do with the shards, although flushing them down the toilet appears to be a no-no. 

Because toenails don’t dissolve in water, they can accumulate in septic tanks, leading to blockages, Biros Septic claims. 

Generally, there is a lack of official advice about what to do with toenail clippings (file photo) 

The NHS you should use nail scissors or clippers to cut your toenails every six to 12 weeks, although it doesn’t say what to do with the clippings. 

‘Cut them carefully and make sure you’re in a light room so you can see clearly,’ the NHS says on its website. 

‘If you have diabetes this is particularly important to avoid injuries to your feet. 

‘Cut them straight across and use a metal nail file to smooth and round off sharp edges.

‘File your nails 2 times a week if you find it difficult to cut your nails.’