Playing with sticky balls will not cause leukemia, but if you play with sticky balls for a long time, you may be at risk of developing leukemia. 1. Sticky balls are made of a combination of adhesive and film, and the main raw material is PVC, or polyvinyl chloride. It has a pungent odor and is highly corrosive, so long-term exposure may be harmful to the human body, but there is no direct evidence that it can cause leukemia. 2. However, sticky balls contain formaldehyde and other chemicals, if long-term contact with sticky balls, may increase the risk of leukemia, so try to avoid contact with sticky balls. At the same time, long-term play with sticky balls may also develop eczema, contact dermatitis and other allergic symptoms. Consult your hematologist for more information.