For every tonne of swimwear and goggles handed over for recycling, Speedo will donate £1,000 to the charity.
Other stars who have kicked off the campaign with their swimming outfits include
Chloe Madeley, Tom Lister, Liz Lock, Lucy Verasamy and Emma Crosby. Athletes Rebecca Adlington, Conrad Williams, Kerri Anne Payne and Liam Tancock have done the same.
Former Spice Girl Mel C said: "This is a great cause, I am glad that my old swimming costume will be recycled but also raise loads of money for Cancer Research.
"It would be great to see everybody joining in and donating last season's swimwear to help this fantastic cause (It's also a great excuse to buy a new cossie!)."
Members of the public donating boy's/men's swimwear at the British Gas Big Dip urban swim festival at Clapham Common, London until July 17 will receive a £5 voucher for new swimwear.
Those donating women's/girl's swimwear will receive a £10 voucher. Those donating old goggles will be able to buy selected goggles for £5 while availability lasts.
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