are table tennis balls prohibited during the security check for luggage (International Flight)

hi, there
I have a question regarding whether table tennis balls are allowed in the luggage for international flight.
I am flying from Shanghai to Toronto with Air Canada, I checked with Air Canada and was told that table tennis balls were permitted in the checked luggage.
I was told by a friend however, that the table tennis balls are prohibited through your security system?
Is it true? Please verify? I am not taking them as carry-ons nor bring them to the plane with me, but put them inside the checked luggages?
Is it allowed.
please let me know, thanks.