Here is a list of the contestants from the main series and their supposed ethnicties. Most of these are derived from Wikipedia in the list of characters article I saw three years ago even though the site isn't accurate. For those whose ethnicity wasn't "revealed" on the site, I assigned one for them. Some are selected randomly for reasons of multicultralism. Some of the contestants ethnicities have already been confirmed by the show itself.

Alejandro: Spanish

Amy and Samey: Icelandic Canadian

Anne Maria: Brazlian Canadian

B: African Canadian

Beardo: African Canadian

Beth: Swedish Canadian

Blaineley: Irish Canadian

Brick: Russian Canadian

Bridgette: Australian Canadian

Cameron: African Canadian

Cody: Finnish Canadian

Courtney: Venezuelan Canadian

Dave: Filipino Canadian

Dakota: French Canadian

Dawn: English Canadian

DJ: Jamaican Canadian

Duncan: Norwegian Canadian

Ella: Swiss-Italian Canadian

Eva: European (most likely Czech)

Ezekiel: Ukrainian Canadian

Geoff: Dutch Canadian

Gwen: Polish Canadian

Harold: Jewish Canadian (though it is unlikely given his surname)

Heather: Japanese Canadian

Izzy: Scottish Canadian

Jasmine: Indigenous Australian

Jo: Danish Canadian

Justin: Native Hawaiian

Katie: Korean Canadian

LaShawna: African Canadian

Leonard: African Canadian

Lightning: African Canadian

Lindsay: French Canadian

Max: Iranian Canadian (most likely Persian)

Mike: Egyptian Canadian

Noah: Indian Canadian

Owen: German Canasdian

Rodney: Irish Canadian

Sadie: Welsh Canadian

Sam: Jewish Canadian

Scarlett: Scottish Canadian

Scott: Irish Canadian

Shawn: Austrian Canadian

Sierra: First Nations (she had mentioned she is part German so it's likely she is mixed)

Sky: Cree

Staci: Hungarian Canadian

Sugar: Northern Irish Canadian

Topher: Belarusian Canadian

Trent: Belgian Canadian

Tyler: Greek Canadian

Zoey: Italian Canadian